Improvements in Machinery for Drying Adhesive and other Substances.
Year: 1898

page_text: Date of Application, 12th July,
1000
7600
Complete Specification Left. 12th Apr. 1899-Accepted. 2nd June. 1899
καιν υ
Complete Specification Left. 12th Apr. 1899-Accepted. 2nd June. 1899
Improvements in Machinery for Drying Adhesive and other
Substances.
I, EMIL GUSTAVUS ADOLPHUS HATSCHEK, of 41, Montserrat Road, Putney, in
the County of Surrey, Engineer, do hereby declare the nature of this invention
to be as follows:
The apparatus herein described is designed to effect the drying, either in
the open air or in vacuo, of substances which adhere to heated surfaces, and form
cakes or lumps with a hard crust impervious to heat and to vapour, so that the
process of drying is considerably retarded.
For this purpose it is necessary, on one hand, constantly, to scrape the heated
walls of the vessel containing the material, and on the other, constantly to break
up and to turn over the material, so as to prevent the formation of the impervious
crust above mentioned.
The apparatus for open air drying consists of an open semi cylindrical vessel
or trough provided with a steam jacket, which may be heated by live or exhaust
steam. The device for scraping the wall of the vessel, and for breaking and
turning the material consists of a number of discs fixed obliquely on a shaft,
these discs are bounded by one straight edge and by somewhat more than half
the ellipse formed by the intersection of the inclined plane of the discs with the
cylinder. In rotating the edge of the disc is therefore constantly in contact with
the cylinder, and scrapes or cleans a length of it equal to the horizontal distance
of the two extreme points of the straight edge of the disc. The discs being fixed
on the shaft at a distance from one another equal to that horizontal distance
the whole length of the trough is constantly scraped, and the formation of a
crust on it is obviated. In rotating the discs also cut up and turn over the
material contained in the trough, and owing to their obliquity, they also impart
to it a motion, which will be in a given direction. If, therefore, the material
to be treated, be fed into the left hand end of the trough, it will be conveyed
to the right hand end, and will there be discharged dried to a degree which
may be regulated by the length of the apparatus and the speed of rotation.
A certain quantity of the material adheres to the discs, and is carried round
and exposed to the air (or vacuum), whereby drying is assisted. To remove these
films or crusts of material from the discs a pair of scrapers is provided for each
disc.
These consist of parallel pieces of angle iron, each pair of these being fixed
together at such a distance as just to allow a disc to rotate freely between the
edges of the horizontal webs of the angles. These scrapers rest on the upper edge
of the steam jacket and an angle iron fixed to the outer shell of the jacket prevents
their being lifted up or carried round by the rotating discs. The scrapers are,
however free to move in a horizontal plane and thus to follow the motion of the
oblique discs. Two projecting teeth are fixed to the angle iron, which bear against
the boss of the disc, and thus prevent the scrapers from being carried over to

page_text: one side by the friction between their edges and the surfaces of the disc. To
allow the material adhering to the disc to be carried round and exposed to the
air (or vacuum) as long as possible, a piece of each scraper is cut out allowing
the layer of material to pass round and to be removed only after half a revolution
of the disc.
The discs may be designed only to act as scrapers, agitators and conveyors for
the material in the trough; or, in addition to this, they may be so arranged as to
convey heat to it. In the former case, they are simple solid dises of suitable
metal; in the latter they are of the following construction. The cast iron (or
gun metal where cast iron is inadmissible) disc has two large openings, over
which are fastened by screws or rivets two sheets of metal thus forming two steam
chambers. The boss of the cast iron framing has a chamber cored in it, which
communicates with the steam space by a T shaped passage.
The spindle carrying the discs is hollow and is supplied with live steam through
a stutting box, at one end, the other end being connected through another stuffing
box with a steam trap. Holes are drilled in the shaft, through which the steam
passes into the chamber in the boss of the disc, and thence through the T passage
into the steam chambers. By constructing the discs in this fashion, a very large
and efficient heating surface is added to the steam jacket.
It will be evident that the construction of the hollow discs may be modified
without departing from the character of my invention.
The apparatus for drying in vacuo is similar in all essential points, but is
of course completely closed, and provided with means for feeding in and dis-
charging the material which are well known and not novel.
Dated this 12th day of July 1808
HARRIS & MILLS.
23, Southampton Buildings, London, W.C., Agents.
Improvements in Machinery for Drying Adhesive and other
Substances.
I, EMIL GUSTAVUS ADOLPHUS HATSCHEK, of, 41, Montserrat Road, Putney, in
the County of Surrey, 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 ;--
:
The apparatus herein described is designed to effect the drying, either in
the open air or in vacuo, of substances which adhere to heated surfaces, and form
cakes or lumps with a hard crust impervious to heat and to vapour, so that the
process of drying is considerably retarded; and it is also applicable to granular
materials containing liquids of a glutinous or sticky nature, such as brewers'
and distillers' grains. It is arranged to work continuously, that is to say,
if the damp material is constantly fed into the machine, a corresponding quantity
of dried material is constantly discharged from it; but it may be modified to take
charges at intervals.
The accompanying drawings illustrate the continuous apparatus for drying in
the open air.
In these drawings Fig. 1 is a cross section and Fig. 2 a longitudinal
section of the improved machinery. Fig. 3 is a face view, and Fig. 4 a plan of
one of the discs with its scraper in position. Figures 5 and 6 are cross sections
of the scraper drawn respectively on the lines 5, 5 and 6, 6 of Fig. 4. Fig. 7

page_text: is a cross section through one of the discs shown in the previous figures. Fig. S
is a face view and Fig. 9 a plan of a solid disc. Fig. 10 is a face view and Fig. 11
a plan of a disc for use without scrapers. Fig. 12 is a half elevation of the
front cover of the apparatus as seen from the inside and Fig. 13 is a half elevation
of the back or discharge cover as seen from the outside.
The mechanism used to attain this object has to perform three operations, in
addition to heating the material under treatment, it must break it up and
turn it over, so as to prevent the formation of lumps and to allow the vapour to
cscape; it must constantly scrape or cleanse all heated surfaces in contact with
the material to prevent its forming a non-conducting crust thereon and lastly
it must convey the material through the apparatus at a suitable rate so that it
leaves it dried to the desired degree. This is effected by the following arrange-
ments.
.I
The material to be treated is fed into a semi-cylindrical or cylindrical vessel A
provided with a steam jacket B or other means of heating the same. A spindle C
passing through the axis of the cylinder, carries a series of discs D) fixed obliquely"
thereon, all inclined at the same angle, the upper portion of one disc being, when
the small axis of the ellipse is horizontal, in a vertical line with the lower portion
of the adjacent disc on one side as shown in Fig. 2, so that every portion of the
semi-cylindrical or cylindrical surface is scraped thereby. The edges of these
discs are formed to the ellipse generated by the inter-section of the inclined plane
with the cylindrical surface i.e., they touch or nearly so the cylindrical wall of
the vessel all round. Supposing the vessel to be partly filled with a granular or
plastic material, and the discs to be revolving, they would keep moving the
material backwards and forwards, and turning it over. It is also obvious that if
the discs were complete ellipses, the thrust exercised by one semi-ellipse (dividing
the ellipse along its great axis) would be counterbalanced by the action of the
other semi-ellipse, which brings the material back to its first position, and that
thus no conveying of the material would take place. If however, a segment of the
elliptical disc is cut away (the chord being parallel with the great axis of the
ellipse) the thrusting action of the corresponding segments in the other half is
left unbalanced, and, in addition to the material being turned over and over, a
portion of it advances within reach of the next disc; the amount thus conveyed
being roughly proportionate to the area of the segment. The nature of the
material determines these two factors: viz. the inclination, and the area of the
segment; if the material dries slowly and must be broken and turned over
energetically, the discs are strongly inclined and only a small segment is cut
away; if on the other hand, the material is to be passed through rapidly, the
discs are not inclined so much but a larger segment is cut away.
In rotating, the edge of each disc is constantly in contact with the cylinder
and scrapes or cleans a length of it equal to the vertical projection of the longer
axis of the disc.
It is therefore obvious that the edges of the discs, in rotating constantly touch
and scrape the whole length of the cylindrical vessel or trough and thus prevent
the formation of any skin or crust on it.
If therefore the material to be treated be fed into the left hand end of the
trough, it will be conveyed to the right hand end and will there be discharged
dried to a degree depending on the length of the apparatus, the inclination and
area of the discs and the speed of rotation.
cess.
The discs also carry portions or a film of the material round with
them exposing them to the air, and thus accelerating the drying pro-
As these would gradually form
crust
a
on the discs, scrapers
are provided for cleaning constantly the surfaces of the discs. The general shape
of these scrapers is shown in Figures 3 to 6. They consist of two bars a a joined
The cross
at the ends bb where they are provided with a pair of trunnions c c.
section of these scrapers is different on each side of the centre line, the section
on one side being shown in Fig. 5 and that on the other in Fig. 6. On one side,

page_text: the two bars are inclined outwards and leave just enough room between them at
their upper edges to allow the disc to pass. This is the side of the apparatus, on
which the discs travel downwards, the film or layer of material adhering to them,
after exposure to the air for the period of about half a revolution is scraped off
by the edges of the bars, and owing to their shape and inclination, drops back into
the vessel. To allow the disc to carry the material round, the other half of the
scraper bars is shaped to the section Fig. 6 where they are quite clear of the
faces of the discs, and are only made to touch it just at the circumference. This
is necessary to guide the scrapers (which are free to move in a horizontal plane,
and to rock on the axis of the trunnions) which, as the discs rotate, oscillate through
an angle equal to the inclination of the discs.
The tendency for the scrapers to be thrust to one side by the discs is obviated
by their ends bearing against the trunnion bearings but if desired two projecting
teeth may be fixed to such scrapers which teeth bear against the boss of the disc as
will be well understood.
The discs may be designed simply for the purpose of breaking up, turning and
conveying the material.
Or the
In that case they are plain discs of suitable metal, as shown in Figures 8 and 9.
The "entering" corner is provided with a sharpened spur id, to dislodge any
material which may accumulate in the scraper, where the disc enters it.
"discs may be so constructed as to convey heat to the material in addition to the
heat provided by the jacketed cylinder. Their construction in this latter case
is shown in Figures 3, 4, 7. They consist of discs D of suitable metal, having a
large opening which may if desired be divided by a central web.
Over the opening or openings, plates f f of metal are fastened and a chamber
or chambers is or are thus formed, into which steam is admitted, The discs
are fixed on a hollow spindle C, and have bosses g in which a' chamber h is cored
or recessed, when only a single opening is formed in the disc as shown in the
drawings this chamber communicates on one side, through a port i with the large
steam chamber in the disc and on the other with the central passage k in the
spindle through a hole 7 drilled through the metal of the spindle but when two
openings or chambers are formed in the disc a T shaped port will be required.
Steam is admitted to one end of the spindle through a pipe passing through a
stuffing box as the discs reach their highest positions, the condensed water
collected in them drains back into the hollow spindle, and passes away at the
other end, through an exhaust pipe passing through a stuffing box.
Another form of disc is shown in Figures 10 and 11. This is employed in the
second part of the apparatus in cases where the material such for instance as
brewers' grains ceases to be adhesive after having been partly dried in the first
or entrance part of the apparatus in which latter part discs of the character herein-
before described are used.
As no material under these conditions adheres to the discs it is no longer
necessary to use scrapers but some means must be provided to carry the stuff
round, and expose it to the air. For this purpose two or more involute vanes or
blades m are fixed to the discharge side of the disc, which in revolving pick up
the material and drop it along the heated face of the disc.
Where solid discs are used, they may be kept slightly warmed by being fixed
on a hollow spindle through which steam is passed, heat being communicated to
the discs by convection from the spindle.
The general. disposition of an apparatus for drying continuously in the open
air is illustrated in the accompanying drawings. A semi-cylindrical trough A
of suitable metal provided with a jacket B rests in cast iron saddles F. The two
ends are provided with covers G G¹ bolted to flanges provided on the saddles or
standards, bearings for the centre spindle C are formed in these covers.
cover G at the front or feed end extends right over the whole section of the trough,
the other cover G¹ has an opening H at the bottom provided with a spout, or
lip from which the dried material is discharged. The front cover further carries
The

page_text: a. hopper socket I and a suitable contrivance for supplying the material fed into
the hopper to the drying apparatus at a uniform rate.
Any of the contrivances generally used for similar purposes may be employed,
such as feed rollers, or archimedean screws, the drawing shows a star wheel K
with involute arms for use with granular materials.
Angle irons L L are fixed on the edges of the cylindrical trough A on which rest
the trunnions c c of the scrapers, illustrated in detail in Figs. 3 & 4. A second
pair of angle irons L' L' is fixed above the first, to keep the scrapers down, whilst
at the same time it permits them to oscillate in a horizontal plane and to rock
on the trunnions and thus to follow the motion of the discs, A cover provided with
a stack or stacks for carrying off the vapour, may rest on these angle irons, to
prevent the loss of heat from radiation.
Steam is supplied to the jacket and to the hollow spindle carrying the discs D
by two separate branches M M from a suitable steam main N, the admission
to each being regulated by a valve, two pipes O leading to a common exhaust
pipe P or a steam trap, lead away the waste steam and condensed water. The
apparatus is shown provided with a worm Q and worm wheel Q for rotating
the disc spindle C but other means may be employed.
To simplify the drawing, the discs are shown fixed parallel to one another.
It is however preferable to arrange them in such a fashion that the whole system
becomes balanced, which can be effected by putting one half of the discs at an
angle of 180° from the other half or by setting them screw wise round the spindle.
The apparatus for drying in vacuo is similar in all essential points, but is of
course completely closed and provided with means for feeding in and discharging
the material which are well known and not novel.
If the apparatus is to receive charges at intervals, instead of being supplied con-
tinually, the same arrangement of discs and scrapers is employed as described
above. The axis of the apparatus is however inclined at an angle slightly greater
than the angle of rest of the material. The apparatus having been charged with
material the discs are made to revolve in such a direction, that they push the
material towards the higher end of the containing vessel; as soon as the discs
leave the material, it falls back owing to the inclination of the vessel, into its
former place.
When the drying process is completed, the rotation of the discs is reversed
and thus assist the material to slide down the inclined container at the lower
end of which it is discharged. An arrangement of this description is particularly
suitable for drying in vacuo, where continuous working would necessitate com-
plicated air locks or similar contrivances.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is :-
1. The arrangement of inclined discs, fixed on a spindle and rotating in a
heated vessel of cylindrical or partly cylindrical shape and having an
elliptical outline so as to touch the interior surface of the cylinder
all round, except for a segment of suitable size for turning, break-
ing and conveying the material contained in the cylindrical vessel, and
for constantly scraping and cleansing the surface of that vessel, sub-
stantially as herein set forth.
2. The arrangement of inclined discs, fixed on a hollow steam heated spindle
provided with connections for the admission of steam and for taking away con-
densed water, such discs rotating in a heated vessel of cylindrical or partly
eylindrical shape and having an elliptical outline so as to touch the interior
surface of the cylinder all round except for a segment of suitable size, for heating
turning, breaking and conveying the material contained in the cylindrical vessel
said discs being made hollow and so connected to the steam heated spindle as to

page_text: be kept heated when working by steam from this spindle substantially as herein
set forth.
3. The use of scrapers for scraping and cleaning constantly the surface of the
discs, of such a shape, that they allow the material adhering to the discs to be
carried round and exposed to the air or vacuum for the space of about half a
revolution before removing it, whereby the drying process is materially assisted
said scrapers being so arranged as to follow the changing positions of the surfaces
of the discs substantially as herein set forth.
4. In machinery for drying adhesive and other substances the combination of
a heated cylindrical vessel, a steam heated spindle, elliptical shaped discs on
said spindle and scrapers acting with said discs and so arranged as to follow the
changing positions of the surfaces of the discs substantially as herein set forth.
Dated this 12th day of April 1899.
HARRIS & MILLS,
23, Southampton Buildings, London, W.C., Agents.
HARRIS & MILLS,
23, Southampton Buildings, London, W.C., Agents.