Improvements in Flexible Tubing or Hose for the Pneumatic Conveyance of Grain and other Matters.
Year: 1894

page_text: Date of Application. 21st July, 1894.
Complete. Specification Left, 22nd Apr., 1895-Accepted, 22nd June, 1895
PROVISIONAL SPECIFICATION.
Improvements in Flexible Tubing or Hose for the Pneumatic
Conveyance of Grain and other Matters.
I, FREDERIC ELIOT DUCKHAM, of Millwall Docks, London, Engineer, do
hereby declare the nature of this invention to be as follows:-
My invention relates to the construction of flexible tubing or hose for the
pneumatic conveyance of grain and other granular or pulverulent matters, and
the invention has for its object to provide the hose with a metallic lining whereby
to protect the interior of the hose from the attrition of the grain or other
matters passing through it, and also prevent the collapse of the hose under the
external atmospheric pressure when the conveyance of the grain or other matters
is effected by an exhaust current of air.
It is essential to the function of such an internal armouring or lining for the
hose that the flexibility of the hose shall not be impaired to any great extent,
that the lining or armouring shall protect the whole internal surface of the hose,
and shall neither gape at the joints, when the hose is bent, and so expose the
rubber or other fabric to the attrition of the matters being conveyed, nor be
liable to nip the fabric in the joints and thereby cause undue friction and wear
of the hose at those points.
The improvements of my invention are designed to provide a lining which,
whilst effectually complying with these essential requirements for the protection
of the hose from injury, is easily removable for inspection, and renewal when
required and does not itself present such obstruction as to cause injury to the
grain, being conveyed nor give rise. to such an increased amount of friction as
to materially retard the conveyance of the grain through the hose.
My improved lining or internal armouring is made of thin, steel or other metal,
and according to one arrangement I construct the lining in the form of an armillary-
tube formed of a connected series of short tubes or annuli of thin metal adapted to
fit into each other easily and overlap at the joints to a sufficient extent to permit of
flexure to the required degree without causing the joints to gape.
With this object the rings may be made slightly conical either from one end
to the other or for a short distance from one or both ends, the remainder.being
cylindrical, the conical end of reduced diameter fitting easily into the cylindrical,
or conically flared end of the adjacent ring.
These rings or tubes, are connected together by pairs of lugs or links formed
of thin flat metal connected to the rings, at about the middle of their length,
alternate pairs being at 90 degrees apart in the circumferential direction so to
permit, of flexure at alternate joints in planes at right angles to each other, or
the rings may be connected to each other by say four equidistant tapes pinned to
each ring.
The flexible armillary tube thus formed may be made of such lesser diameter.
than the hose as to admit of its being drawn into the outer tube of rubber and
canvas, after the latter has been made. in the ordinary way, the lining, being
ecured, in position, therein by connection to the end pieces or couplings and if
ecessary to the outer, tube at intermediate points.
A lining so, introduced is readily removable for inspection and renewal when
equired.
Instead, of the, armillary construction above described, the lining may, be made
of a spirally-coiled narrow, strip of sheet metal specially rolled so that the coils

page_text: may overlap and either be connected by flat links or tapes, as above described, or
by the edges of the strip being previously flanged in opposite directions, the strip
being coiled so that the inwardly flanged edge overlaps the outwardly flanged edge
to a sufficient extent to permit of the play necessary for flexure, the flanges
engaging on the limit of flexure being reached, so as to prevent gaping of the
joints.
Instead of the strip being flanged it may be slightly corrugated at about the
middle of its width the corrugations extending longitudinally of the strip and
parallel to its edges, so that when the tube is spirally coiled with its edges over-
lapping as before, the corrugations form a bed for binding wires wound spirally
around the outer tube after the spirally coiled strip has been introduced therein, 80
as to securely connect each convolution of the spiral strip at the middle of its
width to the outer tube thereby continuously holding the lining in position whilst
leaving the overlapping edges complete freedom to play when the tube is flexed.
When the lining is formed of a spirally coiled strip it may be easily introduced
into the outer tube by giving it extra twist so as to temporarily reduce its
diameter, and then allowing it to slightly untwist and expand again after it has
been introduced.
In all cases the direction in which the grain is blown through the tube should be
such that it will not encounter, and be injured by, the inner edges of the rings
or strip.
314 T.... 1004
A. M. & WM. CLARK.
Improvements in Flexible Tubing or Hose for the Pneumatic
Conveyance of Grain and other 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 :-
This invention relates to the construction of the flexible tubing or hose used for
the pneumatic conveyance of grain and other granular or pulverulent matters by a
current of air, and the invention also relates to the construction of the delivery
nozzle attached to such hose for depositing the matters so conveyed in confined
spaces, as described in the Specification of previous Letters Patent granted to me
and dated the 3rd day of January 1894 No. 198. Such hose has usually been
made of rubber coated canvas stiffened by helically coiled steel wire embedded in
the substance of the hose to prevent it collapsing under the external atmospheric
pressure when working with an exhaust current, but such hose has been liable to
be rapidly worn and cut through by the attrition of the grain especially at the
internally projecting corrugations or protuberances caused by the wire embedded
in it or consequent on the flexure of the hose in directing it towards the point
whence the grain, etc., is to be taken or where it is to be delivered, as the case
may be.
The present invention has for its object to provide the hose and nozzle with a
flexible metallic lining whereby to completely protect the interior surface of the
rubber from the attrition of the grain, etc., passing through it and also to prevent
collapse of the hose under external atmospheric pressure when the conveyance of
the grain, etc., is effected by an exhaust current of air. It is essential that such an
internal armouring or lining shall not materially impair the flexibility of the hose
or nozzle and that it shall protect the whole internal surface, even when the hose is
bent, that is to say it shall neither gape at the joints and expose the rubber

page_text: covering, nor be liable to nip the covering in the joints and thereby cause friction
and wear of the hose at these points. Furthermore, the lining, whilst complying
with these requirements, must not present such obstruction as to cause injury to
the grain or retard its passage through the hose.
Reference is to be had to the accompanying drawings, forming part of this
Specification, wherein
Figure 1 represents a length of hose and delivery nozzle for working with a
current of compressed air the covering being partly in section to show the lining
of my invention.
Figure 2 is a cross-section, on a larger scale, and Figure 3 is a corresponding
part longitudinal section, part of the lining being in elevation.
The same letters of reference denote like parts in all the figures.
A is a length of hose provided with an internal armouring or lining made of thin
steel or other metal, in the form of an armillary tube constructed of a connected
series of short tubes or sections a whereof the ends are adapted to fit into each
other easily and overlap at the joints to a sufficient extent to permit of flexure to
the required degree without allowing the joints to gape. With this object the
tubes or sections are made slightly conical, so that the smaller end of the one may
fit in the larger end of the next, and they are connected together by longitudinal
strips of webbing (preferably of the kind known as "weaver's" webbing) not less
than four in number, arranged at equal distances apart and connected to each tube
or section a by rivets c and washers d. By the use of four, or more, such strips,
the tubes or segments are always held in place, so that the continuity of the lining
is ensured and the joints are prevented from gaping at the outer part of the curve
to which the hose is flexed, the effect of the flexure being to cause the tubes or
sections to still farther overlap at the inner part of said curve, as shewn in
Figure 1.
course,
The proportions and degree of conicity which I find suitable for the tube
sections a are 4 inches length, th of an inch thickness, 6 inches outside diameter
at the larger end, and 5 inches diameter at the smaller end, but I do not, of
linit myself to these proportions, which are given by way of example only.
The flexible hose covering e would be made of about the same internal diameter
as the maximum outside diameter of the tube sections a, so that, after the sections
have been connected together, the armillary tube thus formed may be drawn into
the outer tube or covering e which should fit tightly thereon. The tube e may be
made of rubber and canvas, in the ordinary way, but without the spiral wire
usually embedded in such hose. It should be of such thickness as not to be liable
to be forced by the external atmospheric pressure into the joints between the tube
sections a.
In order that the grain may not encounter, and be injured by, the edges of the
inner ends of the tube sections, the direction in which the grain is carried through
the hose should be from the larger to the smaller end of the cone, as indicated by
the arrow.
The internal armouring or lining when thus introduced is held in place
by being secured to the end pieces or couplings of the hose. The connection with
the coupling is made by the end section a' being, say, half as long again as the
others and of proportionately greater diameter at the larger end, so as to adapt it
to receive within it the thimble f¹ of an ordinary coupling upon which the outer
tube of rubber e is bound, in the usual manner. At the other end the section a² is
received within the thimble n¹ of the coupling n connecting the length of hose to
the next length, or to the enlarged extension or delivery nozzle N.
This delivery nozzle N is a tube of greater diameter than the hose, of which it
forms an extension, and its function is fully explained in the Specification of my
previous Patent aforesaid. The construction of the lining or internal armouring
of this nozzle is precisely the same as that of the hose of which it forms a con-
tinuation, the first tube section as being connected by its larger end to the
thimble 2 of the coupling n by which the nozzle is connected to the hose A and
all the tube sections having their smaller ends directed towards the delivery end

page_text: of the nozzle. The covering of this nozzle may be of canvas, no rubber being
required.
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 flexible hose for the conveyance of grain and other granular or pulverulent
matters by a current of air, consisting of an outer covering of rubber coated
canvas, and an internal armour or lining fitting therein, as described, and con-
structed of a series of short conical overlapping tube sections connected together
by longitudinal strips attached to each such tube section so as to prevent gaping of
the joints by flexure, substantially as specified.
2. A flexible delivery nozzle for hose used for the conveyance of grain and
other inatters by a current of compressed air, consisting of an outer covering and
an internal armour or lining fitting therein and consisting of a connected series of
short conical overlapping tube sections, substantially as specified.
3. The herein described improved flexible hose and delivery nozzle each lined
with a connected series of short conical overlapping tube sections, as and for the
purpose specified.
Dated this 22nd day of April 1895.
A. M. & WM. CLARK,
53, Chancery Lane, London, Chartered Patent Agents.