Seeds, Fabrics, Hides, and other Material.
Year: 1887

page_text: Date of Application, 10th Dec., 1887
Complete Specification Left, 10th Sept., 1888
Complete Specification Accepted, 23rd Nov., 1888
Seeds, Fabrics, Hides, and other Material.
AMOS HERBERT HOBSON of 5 Westminster Chambers Victoria Street in the City
of Westminster Analytical Chemist and JOHN RADCLIFFE CROFT of Old Trinity
House 5 Water Lane in the City of London Merchant do hereby declare the
nature of this invention to be as follows:
Our Invention has for its object the production by improved system and means of
heated air and the application of the heated air so produced to the desiccation of
substances contained in or intermixed with liquids such as solutions of solid matters,
meat, grain, seeds, fabrics, hides tea &c.
To produce the heated air we employ a furnace or other source of heat which
communicates directly with an inner Hue or channel through which the products of
combustion of the said furnace or other source of heat can pass to a chimney.
Surrounding this inner flue or channel we place or construct another flue or channel
into one portion of which the air to be heated is admitted, afterwards passing out of
the said outer flue or channel into the stove or drier containing the substances to be
desiccated, the direction of motion of the air in the outer flue or channel being the
reverse of that of the air and products of combustion in the inner flue or channel.
The stove or apparatus in which the heated air is to be used for desiccation may be
of any convenient size or form proportionate to the heating power of the furnace or
other source of heat. For the purpose of drying solutions or liquid extracts we
provide the stove or apparatus with shelves to each of which or in some other suitable
way we affix flanges or lips which deflect portions of the current of heated air over
and beneath the said shelves. For the purpose of drying substances in a solid or
semi-solid state which contain or are intermixed with liquid matter we substitute for
the above mentioned shelves other shelves with perforated bottoms.
For the purpose of drying substances which possess a large area of surface such as
fabrics hides, skins &c. we omit the said shelves from the stove or apparatus and
substitute hooks or other supports for the said substances in such a manner that air

page_text: may circulate freely between them. By the above means the contents of the stove or
apparatus before mentioned are heated, the liquid contained therein is more rapidly
vaporized and the vapour so produced is carried away out of the stove or apparatus
by the current of air. In order to still further increase the desiccating power of the
stove or apparatus we so construct it that the chimney or exit for air and vapour from
the stove or apparatus is heated by the waste heat passing up the chimney from the
furnace or other source of heat, by this means aiding the draught through the said
stove or apparatus. To economise the heat from the furnace or other source of heat
we encase the inner flue or channel of the furnace or other source of heat in iron plates
or sheets by which means the heat of the inner flue or channel is more rapidly
communicated to the air in the outer flue or channel.
By the system and means above mentioned any kind of fuel may be burnt in the
furnace or any other convenient source of heat employed to produce the heated air
which will be as pure as that of the surrounding atmosphere and free from danger to
or action upon the substances to be desiccated. The heated air may be raised to a
moderate or to a very high temperature in the flue or channel and will enter the stove
at its maximum temperature. The amount of air to be heated entering the outer flue
or channel of the furnace or other source of heat is regulated by means of valves or
doors which allow of or cut off communication between the atmosphere and the outer
flue or channel. The heat imparted to the air to be heated in the outer flue or
channel may also be regulated by the size or power of the furnace fire or other source
of heat.

page_text: Seeds, Fabrics, Hides, and other Material.
We, AMOS HERBERT HOBSON, of 5, Westminster Chambers Victoria Street, in the
City of Westminster, Analytical Chemist, and JOHN RADCLIFFE CROFT, of Old
Trinity House, 5, Water Lane, in the City of London, Merchant, 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 an improved system of hot air stove for desiccating aqueous
solutions, extracts, meat, skins, hides, fabrics, grain seeds, tea, etc., etc.
The Invention consists essentially in a system of apparatus wherein the air to be
heated is caused to travel in the inverse direction to the products of combustion in
such manner that the air will enter the drying apparatus at its maximum temperature,
and wherein the waste heat of the escaping products of combustion is utilized to
promote the draught through the drying apparatus whereby the maximum of useful
effect is obtained with a minimum consumption of fuel.
Reference is to be had to the accompanying drawings forming part of this specifica-
tion, wherein figure 1 is a longitudinal vertical section, figure 2 a horizontal section,
figure 3 a cross-section, and figure 4 an external elevation, of the apparatus. Figure 5
is a detail. The same letters of reference indicate the same parts in all the figures.
A is the furnace chamber and B a horizontal flue leading therefrom to the chimney C.
Surrounding the flue B is an air-heating flue 1) having an air inlet at the end
farthest from the furnace and communicating at a point immediately over the furnace
chamber with the drying chamber above. The drying chamber E is separated, except
at the end above the furnace, from the flue D by a horizontal partition F and it is
fitted with removable trays G to contain the substances to be desiccated access being
had thereto through an opening in the side wall of the drying chamber closed by a
sliding or other shutter H. The chamber E communicates at the end farthest from
the furnace with an uptake or flue I surrounding the chimney C.
By this arrangement, the air entering the flue D at the inlet d is caused to travel
in the opposite direction to the products of combustion passing through flue B, and
to enter the stove at its maximum temperature. The heated air passes through the
stove or drying chamber over and between the trays or shelves therein, and thence
into the uptake I, the cooling of the air in the stove and the consequent retarding of
the current of air being counteracted by the rarefaction in the uptake due to the
radiant and other heat from the chimney C, which passes through the uptake, as above
mentioned.
It is found advisable, when possible, to slightly incline the trays or shelves in the
stove upwards towards the chimney, so as to facilitate the disengagement of the vapors
arising from the substances being dried, and assist in promoting the draught.
The flue B is constructed of thin fire-brick, cased externally, with iron plates, or it
may be made entirely of iron, and it is supported on bearers b. From the division

page_text: plate F depend baffle plates which serve to deflect the air passing through the
Hue D down on to the top of the flue B. The outer walls of the furnace and drying
chamber are of brickwork in which are fixed angle-iron guides K for the shelves or
trays. These angle-iron guides K are fixed transversely in the drying chamber,
being embedded in the brickwork at one end, and supported at the other end by iron
uprights fixed in the doorway closed by the door H. To the angle-irons nearest
the furnace, are fixed deflectors which may be made adjustable so as to regulate the
quantity of hot air passing between the several ranges of shelves or trays. The latter
may be constructed to hold liquid, or they may be perforated and smaller trays or
other suitable receptacles may be placed upon them. When the stove is to be used
for drying hides, skins, or other materials having a large extent of surface, the shelves
or trays may be removed from the stove, the articles to be dried being suspended from
hooks or other suitable supports attached to the angle irons K.
The sliding door H, by which access is had to the interior of the drying chamber,
is fitted to slide in guides attached to the flank wall of the chamber, and is counter-
weighted by weights attached to chains passing over pulleys, as shewn, and access
may be had to the upper or lower ranges of shelves or trays as may be required, by
sliding the door either downwards or upwards, as the case may be, only those shelves
or trays being uncovered to which access is required so that loss of heat is, as far as
possible, avoided.
The internal chimney C, for the escape of the products of combustion, is constructed
of iron plates which may be suitably stayed at intervals to the brickwork shaft
enclosing the outer flue or uptake I for the air and vapors.
In the example shewn, both the inner and outer chimney are constructed of
approximately triangular form in section, with the object of combining in one shaft
the chimneys from four such stoves as that above described, but the concentric
chimneys may be of circular, or other, section if preferred.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed we declare that what we
claim is ;-
1st. The herein-described system of drying stove constructed and arranged
substantially as above described and shewn in the drawings, and wherein the air to be
heated travels through a horizontal flue surrounding the flue conveying the products
of combustion-tlie air moving in the inverse direction to the products of combustion
and entering the drying chamber at a point adjacent to the furnace-and wherein the
heat from the furnace chimney is utilized to rarefy the air in the uptake flue, and so
promote the draught in the stove, as set forth.
2nd. In the herein described apparatus, the employment in connection with the
superposed tiers of shelves or trays, of adjustable deflectors to regulate the distribution
of the current of heated air to the several tiers of trays, substantially as specified.
Dated this 10th day of September 1888.
A. H. HOBSON.
J. R. CROFT.
By A. M. & Wm. Clark,
53, Chancery Lane, London,
Patent Agents.