Improvements in the Method of and Means for Elevating and Conveying Grain and other Matters in Bulk by Pneumatic Agency.
Year: 1893

page_text: Date of Application, 22nd Nov., 1893
Complete Specification Left, 22nd Aug., 1894-Accepted, 17th Nov., 1894
PROVISIONAL SPECIFICATION.
Improvements in the Method of and Means for Elevating and
Conveying Grain and other Matters in Bulk by Pneumatic
Agency.
1, FREDERIC ELIOT DUCKHAM of Millwall Docks, Poplar, London, Civil
Engineer, do hereby declare the nature of this invention to be as follows:-
My invention relates to elevating and conveying grain or other granular or
pulverulent matters in bulk by pneumatic agency in the operations of loading or
unloading ships' cargoes or transferring the grain, etc., from one place to another.
The invention has for its object to enable a current of air under pressure to be
effectively applied to act on the grain, etc., for the purpose of raising and conveying
the same by ensuring that the proper relative proportions of the grain or other solid
matters to the carrying current of air shall be maintained under varying conditions
of working, so as to avoid choking of the conveying pipes.
The invention consists essentially in injecting the air current into the midst of
and below a mass of grain or other material to be elevated and conveyed so as to act
on the same at such a depth that the weight and density of the superincumbent
mass will be sufficient to overcome the expansive pressure of the air jet and prevent
the escape of the air through the mass, the conditions being such that the grain, etc.,
will be fed by gravity directly into the path of the air-blast so that it will be acted
on positively by the direct force of the air blast and uot merely by air currents set
up by the inductive action of the blast.
the
For the purpose of carrying this method into effect the invention comprises,
first, the combination, with a nozzle and surrounding adjustable air sleeve, as
described in another application for Letters Patent dated the 22nd day of
February 1893, No. 3944 (which is there described as working with an exhausted
current of air) of means whereby a current of air under pressure is supplied to the
air sleeve under such conditions that it is caused to act on the grain, etc., in which
the nozzle and sleeve are immersed in such way as to carry it up through the nozzle
and out through the conveying pipe to any desired point of delivery, and this
whether the grain be supplied to the containing vessel in which the nozzle is
placed, by hand labor or by other means, and whether such vessel be open to the
air or closed and under the pressure of the conveying current; secondly,
combination, with the outlet nozzle, of an air nozzle, oppositely directed to, and
axially in line with, the exit nozzle, the two nozzles being immersed in the grain, etc.,
and so arranged relatively to one another that the grain will flow by gravity into
the path of the air current in due proportion to the volume of the latter whether
the containing vessel be open or closed and under a corresponding air pressure;
thirdly, the combination, with the above mentioned closed chamber and nozzle with
air sleeve or nozzle immersed as above described in the grain, etc., therein contained,
of the oscillating air-lock delivery box, also described in my aforesaid previous
application, by which the grain after being elevated and conveyed to the delivery
box by an exhaust current is mechanically supplied to the said closed chamber to
be further conveyed by a current of air under pressure.
When employing an open vessel to contain the grain, etc., to be raised and
conveyed, the air supply pipe is connected directly with the surrounding sleeve, or
with the air nozzle, as the case may be, the sleeve, if used, being open at the lower
end only and terminating near the mouth of the outlet nozzle whilst the air nozzle
would be situated in axial alignment with the outlet nozzle both the sleeve and the
air nozzle being adjustable with regard to the outlet nozzle and the depth of
immersion in the grain, etc., being such that the weight and density of the latter

page_text: will prevent the escape of the air, otherwise than through the outlet nozzle through
which it must carry the grain along with it.
When employing a closed chamber the arrangement of the outlet nozzle and air
sleeve or blast nozzle is similar except that the pipe supplying compressed air may
also be connected with the upper part of the chamber so as to put the grain, etc.,
therein under similar, air conditions as the carrying current in which case the air
sleeve may be open, at its upper end and rise above the level of the grain, etc., in
the chamber so as to receive the air current wholly through the upper part of said
chamber, or the sleeve may be closed at its upper end and be connected directly
with the air supply pipe as when an open hopper is used.
T
In combining the closed chamber with outlet nozzle working by air under
pressure with the oscillating air lock delivery apparatus above referred to, the
latter may either be wholly enclosed in said chamber or it may be provided with
valve-like outlets working over corresponding seats on passages leading to the
closed air pressure chamber whereby the compartments of the air lock delivery
apparatus are alternately put into communication with the closed pressure chamber
so as to discharge therein at proper times, provision being also made, by the same
or other valves, for establishing communication between the air pressure chamber
and the upper part of the compartment to be discharged so as to establish
equilibrium of pressure at the moment of discharge, the operation of all these
valves being dependent on the oscillation of the air lock delivery apparatus under
the control of its counter-weighted detent mechanism.
Dated this 22nd day of November 1893.
F. E. DUCKHAM,
By A. M. & Wm. Clark,
53, Chancery Lane, London, Chartered Patent Agents.
COMPLETE SPECIFICATION.
Improvements in the Method of and Means for Elevating and
Conveying Grain and other Matters in Bulk by Pneumatic
Agency.
1, FREDERIC ELIOT DUCKHAM, of Millwall Docks, Poplar 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 the method of, and apparatus for, elevating and con-
veying grain and other granular or pulverulent matters by pneumatic agency in
the operation of loading and unloading ships' cargoes, or otherwise transferring the
grain or other pulverulent matters from one place to another.
The invention has primarily for its object to enable the methods of working by
exhaustion and by compression of the air to be combined or applied, the latter in
continuation of the former. It also has for its object to enable the method of
working by compression to be advantageously employed generally, apart from the
method of working by exhaustion.
The invention, so far as it is combined with the exhaust method of working, will
be described in connection with the oscillating air-lock delivery apparatus which
forms the subject of previous Letters Patent dated the 22nd day of February 1893,
No. 3944.
Pneumatic grain conveying apparatus working by exhaustion necessarily
terminates in an air-lock delivery apparatus of some kind by which the grain is
delivered without permitting the influx of the air. Such apparatus is generally
mounted on a barge or on the quay and is used both for loading and unloading
ships, but as it cannot be conveniently placed at such a height that the grain
discharged from it will flow by gravity through the hatchway of a large ocean-
going ship to be loaded or into a warehouse on shore, or at a distant point, the

page_text: conveyance of the grain, etc., from the point at which it is.delivered by the air-lock
delivery apparatus must be effected by other means. By the present improvement
this is effected by a current of air under pressure.
In order to ensure the maintenance of the proper relative proportion of the air
to the solid matters carried thereby and so avoid choking of the pipes under the
varied conditions of working, the improvement in working by compressed air
consists in injecting the air current into the midst of the mass of grain or other
material contained in a closed chamber under pneumatic pressure corresponding to
the pressure of the blast, the air being injected in such relation to the downwardly
directed mouth of an exit nozzle that the grain will be acted on positively by the
direct force of the air blast (and not merely by air currents set up by the inductive
action of the blast) the conditions being such that the grain will be fed by gravity
directly into the path of the blast and will be carried off in the upward direction
as fast as it is supplied to the point of application of the blast so that the feed
cannot become so excessive as to cause choking of the conveying pipe.
Figures and 2 of the accompanying drawings are sectional elevations of two
modifications of apparatus by which the conveyance of grain, etc., by exhaustion
and by compression are combined.
Figures 3 and 4 illustrate the apparatus for conveying by compressed air, when
not directly combined with apparatus working by exhaustion.
The same letters of reference denote like parts in all the figures..
Referring to Figures 1 and 2, D, D', are the two chambers of an oscillating air-
lock delivery box, such as described in my other Patent above referred to. E is the
lower part of an exhausted hopper in which the grain, etc., is deposited by the
exhaust current and from which the chambers D, D', are alternately filled. For
this purpose the delivery box D, D', rocks on an axis D2, its upper face H having
apertures . ', and working like a slide-valve against the mouth of the hopper E.
The oscillation of the delivery box is controlled by detent mechanisms (one for each
direction of motion) each mechanism consisting of a catch i jointed to a counter-
weighted lever I and engaging, under the control of link, with a stud on the
delivery box. is a support for lever I to prevent the catch engaging with
until the corresponding chamber of the delivery box has been partly filled.
G, G', are bye-pass chambers connnected by pipes g,g', with the upper part of
hopper E and they have ports g, y, which coincide at proper times with the
apertures h, h', so that the air contained in the empty chamber D or D' may be
exhausted before the filling of that chamber commences, all this part of the
apparatus being similar to that described in my previous Patent aforesaid.
In order that the grain, etc., delivered by D and D', may be raised and conveyed
still further by compressed air, the air-lock delivery apparatus may either be
enclosed within a closed air-pressure chamber S, as in Figure 1, or the
chambers D, D', may communicate with a similar chamber S placed below them,
as in Figure 2, compressed air being in either case forced into chamber S through
pipe T.
In Figure 1, the detent mechanism which controls the oscillation of the delivery
box is shewn as also enclosed within the air pressure chamber S, but this is not
necessarily the case, as the detent mechanism might be mounted on top of
chamber S and engage with rods attached to D, D', and sliding through stuffing!
boxes in the top of chamber S, so that the working of the detent mechanism would
not be impeded by the dust arising from the grain.
In Figure 1, D, D', have flap doors d, d', which are held closed by the pressure
of the air in chamber S, and in order that they may fall open at the proper
inoment under the weight of the grain the filling apertures h, h¹, open to the
chamber S when the delivery box oscillates to the right or left (as illustrated in
Figure 1 in respect of the aperture h¹) so as to allow air to enter and balance the
external pressure which kept the door closed.
In Figure 2, the chambers D, D', communicate with chamber S through apertures
in valve faces V, V', working over corresponding valve seats W, W¹, on pipes X, X',

page_text: leading to chamber S, and a pipe Y leads from chamber S to passages Y, Y',
communicating with ports in the seat of valve H with which the apertures h, ',
also communicate at proper times for the purpose of establishing equilibrium of
pressure between chamber S and the chamber D or D', which is to be discharged,
the operation in either case being similar to that described in my previous Patent
aforesaid although performed under different conditions as regards air pressure.
S' is a door at the bottom of chamber S for discharging the grain directly from
said chamber instead of conveying it farther, when desired.
The grain delivered into chamber S from D, D', is conveyed away and discharged
where required, by the following means:-Within the lower part of the chamber S
is fixed a nozzle A, having its mouth directed downwards, the nozzle leading
upwards to a pipe U connected to the top or side of the chamber S. Around this
nozzle is fixed a sleeve B of such diameter as to admit air in sufficient quantity to
carry away the grain, etc., in a continuously flowing stream through the conveying
pipes. The nozzle A and sleeve B are immersed in the grain contained in
chamber S, the open upper end of the sleeve rising above the level of the grain,
in order that the compressed air forced into chamber S through pipe T may pass
down the sleeve and carry the grain into the nozzle A. The nozzle projects below
the sleeve and the one can be adjusted with regard to the other, as in Figure 1, or
the sleeve or the nozzle may be provided with a telescopically sliding lower end, as
at a in Figure 2.
The apparatus above described need not necessarily be combined with pneumatic
apparatus working by exhaustion, as the hopper E might be open and charged
with grain by gravity or by hand labour. Or any other form of air lock might be
employed, as in Figure 3, for instance, where the nozzle A and sleeve B are
enclosed in a chamber S supplied with compressed air, as before, and charged with
grain, etc., from an open hopper E through an air-lock formed by independently-
operated valves Z, Z, and intervening chamber 7. In this figure the compressed
air pipe T leads directly into the sleeve B instead of into the chamber S in which,
however, a pressure corresponding to that of the blast is quickly established by
percolation of the air through the grain.
Instead of the air being injected in the downward direction into the mass of
grain through a sleeve surrounding the exit nozzle, it may be injected through an
upwardly directed nozzle, as at B', in Figure 4, in axial alignment with the exit
nozzle A, the two nozzles being contained in a closed chamber S and so arranged
relatively to one another that the grain, etc., in which the nozzles are immersed will
flow by gravity into the path of the blast, the due proportion of the volume of air
to the grain carried by it being ensured by regulating the distance between the
nozzles, the nozzle A being for this purpose adjustable by means of a bolt and
nuts a'. The char ber S may be charged with grain, etc., from an open hopper E
through any form of air-lock, such as the oscillating box before described, or the
valves Z, Z, and the upwardly directed blast nozzle B' may be substituted for the
sleeve B shewn in Figures 1 and 2.
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. The pneumatic elevation and conveyance of grain and other matters by
compressed air by injecting the air current into the midst of the said matters when
contained in a closed vessel under internal pneumatic pressure corresponding to the
pressure of the blast, the air jet being so injected in such relation to the down-
wardly directed mouth of an upwardly directed exit nozzle also immersed in the
grain &c. that the latter will be fed by gravity directly into the path of the blast
and will be acted on positively and directly by the blast and be carried away
thereby through the exit nozzle, substantially as specified.
2. In apparatus for elevating and conveying grain etc. by compressed air, the
combination with a closed vessel continuously supplied with air under pressure and

page_text: provided with any suitable form of air-lock charging device, of a nozzle connected
to a conveying pipe leading out of the vessel, and of an air sleeve surrounding the
nozzle, the nozzle and sleeve being fixed within the closed chamber and their
mouths being downwardly directed and immersed in the grain etc., charged into the
closed vessel, the lower end of the nozzle projecting below that of the air sleeve so
that the grain can flow beneath the sleeve directly into the path of the air passing
down the sleeve, and the sleeve serving to convey the compressed air to the
point where it is to act on the grain for the purpose of conveying it away, as
specified.
3. In apparatus for elevating and conveying grain etc., by compressed air, the
combination with a closed chamber provided with any suitable form of air-lock
charging device, of an exit nozzle having its mouth directed downwards, and of an
upwardly directed air blast nozzle in substantially axial alignment with the exit
nozzle, the nozzles being located within the closed chamber and immersed in the
mass of grain etc., contained therein, the exit nozzle being connected with a con-
veying pipe and the blast nozzle with a supply of compressed air, and the two
nozzles being separated by an interval such that the grain etc., will flow by gravity
beneath the exit nozzle directly into the path of the air blast, substantially as
specified.
4. The combination of the method of conveying grain and other matters by an
exhaust current of air, with the method of conveying the same matters by a current
of compressed air, the latter being applied to act in continuation of the former,
substantially in the manner and by the means specified.
5. In the pneumatic conveyance of grain and other matters by exhaust and
compressed currents of air acting in continuation the one of the other, the com-
bination with the oscillating two-chambered air-lock delivery box having a valve
like connection with an exhausted charging hopper, of an air pressure chamber
supplied with air under pressure and in which the air-lock delivery box is enclosed,
or into which it is adapted to discharge, as described, a valve adapted to establish
equilibrium of pressure between the pressure chamber and the chambers of the
delivery box at the moment of their discharge, an upwardly extending exit nozzle
fixed within the air pressure chamber and immersed in the matters discharged from
the air-lock delivery box, and an air blast sleeve surrounding the exit nozzle, the
sleeve communicating directly or indirectly with the supply of compressed air and
terminating at such a distance above the downwardly directed mouth of the exit
nozzle that the grain etc., will flow by gravity directly into the path of the air
passing through the sleeve, substantially as specified.
6. In the pneumatic conveyance of grain and other matters by exhaust and
compressed currents of air acting in continuation the one of the other, the com-
bination with the oscillating two-chambered air-lock delivery box having a valve
like connection with an exhausted charging hopper, of an air pressure chamber
supplied with air under pressure and in which the air-lock delivery box is enclosed,
or into which it is adapted to discharge, as described, a valve adapted to establish
equilibrium of pressure between the pressure chamber and the chambers of the
delivery box at the moment of their discharge, an upwardly extending exit nozzle
fixed within the air pressure chamber and immersed in the matters discharged from
the air-lock delivery box, and an upwardly directed air blast nozzle in substantial
alignment with the exit nozzle, the blast nozzle communicating with a supply of
compressed air and being situated at such a distance below the downwardly directed
mouth of the exit nozzle that the grain etc., can flow by gravity directly into the
path of the blast, substantially as specified.
Dand thin oond day of Anat 1901
A. M. & WM. CLARK,
53, Chancery Lane, London, Chartered Patent Agents.