Improvements in and connected with Apparatus for Roasting, Heating, or Drying and Mixing Coffee, Chicory, Cocoa, and similar Granular Substances.
Year: 1890

page_text: Date of Application, 21st June, 1890
Complete Specification Left, 21st Apr., 1891-Accepted, 30th May, 1891
PROVISIONAL SPECIFICATION.
Improvements in and connected with Apparatus for Roasting,
Heating, or Drying and Mixing Coffee, Chicory, Cocoa, and
similar Granular Substances.
I, ALFRED PAVITT, of 94, Sandringham Road, Dalston, in the County of
Middlesex, Commercial Traveller, do hereby declare the nature of this invention
to be as follows :—
This invention relates firstly, to a certain improved construction of combined
apparatus whereby the operations of roasting heating or drying and mixing or
agitating granular substances may be performed either simultaneously or separately
without damaging the materials and at the same time preserving their aroma,
and secondly to a special construction of the mechanical agitator for the purpose.
I arrange two vessels preferably cylindrical and with end plates either concentrically
or eccentrically so that an air space intervenes. Both vessels are cut away and
left open for a suitable portion of their circumference, say th, at the upper part
and the space between them is plated up. The open top is or may be provided
with a slide for regulating its area as required.
In the inner vessel or roasting chamber is placed a central rotary spindle carrying
the specially arranged agitating device hereinafter specified.
The spindle bears in the end plates and is furnished externally with a handle or
power pulley. The substances to be treated are placed in the inner vessel and
heat is applied by gas jets coke fire or otherwise to the vessel so that when the
agitator is rotated the two operations of roasting and mixing will be simultaneously
performed, but it is obvious that they may be separately effected. A safety valve
or equivalent device to compensate for the expansion of the air and the materials is
or may be applied.
The special agitator is constructed as follows:
On the rotary spindle are two single wings, one at each end in the same plane,
and sloped in an inward direction for clearing the ends and throwing the substances
towards the centre.
At right angles to these are two single wings also in the same plane at either
side of and equidistant from the centre of the spindle sloped in an inward direction
for picking up the material delivered from the ends by the first pair aforesaid. At
right angles to these is one double wing at the centre point sloping in both
directions towards the ends for lifting and distributing the material from the centre
back to the ends. At right angles to this is a scraper extending the full length of
the vessel.
The air chamber prevents the contact of flames with the roasting chamber and
its contents and the fumes thereupon can pass away freely, at the open top. Each
revolution of the agitator causes the material to be thrown from the ends to the
centre, and then raised from the centre and distributed back to the ends, the scraper
raising the residue from the bottom and throwing it on to the top and likewise
clearing the sides.
Thus a certain quantity is always in contact with the bottom of the roasting
chamber and allow to roast for a short time only, preventing any material from
remaining in the same place and thus the operations are rapidly and efficiently
performed.
To discharge the materials after treatment both the vessels are or may be
arranged so as to be simply turned over.
T
1000

page_text: COMPLETE SPECIFICATION.
Improvements in and connected with Apparatus for Roasting,
Heating, or Drying and Mixing Coffee, Chicory, Cocoa, and
similar Granular Substances.
I, ALFRED PAVITT, of 94 Sandringham Road, Dalston, in the County of
Middlesex, Commercial Traveller, 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 firstly to a certain improved construction of combined
apparatus whereby the operations of roasting heating or drying and mixing or
agitating granular substances may be performed either simultaneously or separately
without damaging the materials and at the same time preserving their aroma,
and secondly to a special construction of the mechanical agitator for the
purpose.
I will further describe my invention in reference to the accompanying drawing
in which
Figure 1 is a half sectional elevation and half side elevation;
Figure 2 is a half sectional and half end elevation.
Similar letters indicate similar parts in both figures.
18
☐ arrange two vessels preferably cylindrical A and B one within the other and
either concentrically or excentrically as illustrated, so that an air space S intervenes
extending around the inner vessel. They may be made of copper, iron, steel or
suitable metal and each has its separate end plates and respectively by which
they are connected together, and those of the inner vessel or roasting chamber A
may be of cast iron as illustrated. Both vessels are cut away and left open for a
suitable portion of their circumference, say for about 4th, marked O at the upper
part and the space between them is plated up at a¹ a¹ so as to confine the said air
space S between them. The open part is or may be provided with a slide or
hinged covers for partly or entirely closing its area as required.
;
The two vessels are mounted upon one central rotary spindle C which passes
through bosses c. e. formed on the inner end plates and is extended and mounted
in bearings in the main frames K. This spindle may carry any kind of mechanical
agitator and in small machines it is furnished externally with a hand operating
handle in the figures which illustrate a large machine, the spindle C is shown
adapted to be driven by power through interposed speed gearing, W being a toothed
wheel mounted on C driven by wheel w on shaft carried in brackets on
frame K, and provided at its other end with fast and loose driving pullies P. In
use the combined vessels A and B are normally stationary in the position shown
and heat is externally applied to the outer vessel A by swivelling gas jets arranged
as shown for example at G G or a preferably removable coke fire or other source
of heat may be employed, by which the air in S will be heated and effect the
roasting heating or drying in the inner vessel B. The sides of the frame K may
be plated up as shown at 3, or the plating can be carried up to any desired height
to confine the heat and fumes which can escape by a pipe arranged at the end
or at the open ends or in any other convenient manner. V is a safety valve to
compensate for undue pressure. The two vessels A and B can be inverted when
required to empty same as illustrated for example by means of an internally toothed
wheel mounted on spindle C and actuated by pinion a mounted on bracket k² fixed
to frame K Figure 2. operated by an ordinary winch handle. With this construction
any suitable mechanical agitator may be used and operated by spindle C but, I have
designed a special agitator which is constructed as follows:-The rotary spindle C is
preferably made square (except in its bearings) and upon it are fixed by screws
and sleeves two single wings D D one at each end in the same plane and sloped in
an inward direction; the function of which is to clear the ends and throw the

page_text: materials towards the centre. At right angles to these are fixed two single
wings E E also in the same plane at either side of and equidistant from the centre of
spindle C and sloped in an inward direction, the function of which is to pick up
the materials delivered by the first pair D D and pass them on towards the
centre.
At right angles to these (i.c. in same plane as first pair) at the centre point is one
double wing sloping in both directions towards the ends the function of which is
to lift and distribute the materials from the centre back to the ends.
At right
angles to this is a scraper H carried on arms h, h, running the full length of the
vessel B and extending radially very nearly to its interior walls.
:
In operation the materials to be treated are placed in the inner vessel or roasting
chamber B and heat externally applied to A; the air chamber S prevents the
contact of the external flames with B, the fumes passing away freely at each
revolution of the agitator the materials are thrown from the ends to the centre by
the pair of wings D D assisted by the pair E E, and back from the centre by the
double wing F, the scraper H raising the residue from the bottom and likewise
cleaning the sides at each rotation.
Thus the two operations of roasting, heating, or drying and mixing or agitating
will be simultaneously performed but it is obvious that they may be separately
effected if desired: A certain quantity of material is always in contact with the
bottom of the roasting chamber B but allowed to roast for a short time only, the
agitator preventing any material from remaining in the same place long enough to be
overheated or damaged, and thus the operations are rapidly and efficiently performed
and the roasting is effected equally over the whole surface of the materials treated
and there being no fumes in contact the flavour and qualities of delicate berries
such as coffee are unimpaired.
When the roasting is completed the gas jets G are turned outwards or the source
of heat otherwise withdrawn and a receiver temporarily placed beneath the
vessels A and B which may then be turned over by the winch handle and gear X, c,
described or otherwise so as to throw out the materials, and then the apparatus being
replaced in position and re-charged the work proceeds.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what |
claim is
1. The hereinbefore described construction of the combined apparatus for the
purpose or purposes specified, consisting in the combination of the normally
stationary outer vessel A and inner vessel B with intervening closed air space S
said vessels being mounted on spindle C carrying a mechanical agitator and heat
being applied to the external vessel A, all substantially as described and illustrated
in the accompanying drawings.
2. The use in an apparatus such as is set forth of a mechanical agitator con-
structed as described, wherein wings D D, E E, and F and the scraper H are
arranged upon the rotary spindle C whereby the materials in the inner vessel or
roasting chamber B and its walls are operated upon during the process as and
for the purposes set forth.
4. The combination and arrangement of parts forming together the apparatus as
a whole substantially as and for the purposes hereinabove described and illustrated
in the accompanying drawings.
J. C. CHAPMAN,
70, Chancery Lane, London, W.C., Agent for Applicant.