Improvements in Apparatus for Drying Tea Leaves, Coffee, Grain, or other Produce.
Year: 1889

page_text: Date of Application, 28th Oct., 1889
Complete Specification Left. 1st Feb., 1890-Accepted, 1st Mar., 1890
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Drying Tea Leaves, Coffee, Grain, or
other Produce.
I WILLIAM JACKSON of Thorn Grove Mannsfield Aberdeen North Britain
Gentleman do hereby declare the nature of this Invention to be as follows:-
My Invention relates to apparatus for use in drying tea leaves coffee or other
produce.
Hitherto tea leaves and other products have been dried or withered in chambers
provided with endless metallic webs or bands placed in a horizontal superposed
position and carried over rollers or sprocket wheels at each end. The first or upper
web by its movement carried the material spread on it forward till the said material
dropped over the end down on to the second web on which the said material was
returned and so on till it reached the bottom band which discharged the dried
material.
My present invention has for its object to provide an arrangement of perforated
trays or troughs connected with pitch chains or their equivalents which will convey
the said trays or troughs in a circuitous path from the bottom to the top of the
drying chamber whilst a current of heated air is caused to pass in a downward
direction through them. I may create the current of air by providing the said
chamber with an inlet for hot air at the top, an exhaust fan or fans drawing the
heated air through an aperture at the bottom. Into this chamber I introduce two
endless pitch chains or the like of equal length one for each side of the chamber the
said pitch chains (or the like) entering at the front end and lower part of the chamber
and passing along near the bottom then turn upwards over sprocket wheels at the
back end of the chamber and return parallel at the bottom part of the chains and
again pass upwards over wheels and then return to the back end of the chamber
and so on as many times as desired till they emerge at the front end near the top
where they continue their path to outside the drying chamber where they pass over
driving sprocket wheels and turning downwards they again enter the lower part of
the drying chamber.
At intervals along the pitch chains I suspend trays or troughs. This may be
effected by providing the chains with ears to receive them and which may also
receive stay rods which pass from one side of the machine to the other that is from
the ears on the chain at one side to those at the other.
On the ears of the chains (which may be used without the rods) I suspend or
pivot in pendulous fashion trays or troughs preferably of a shallow flat bottomed disc
shape in close succession to each other so as to constitute in effect a web extending
from side to side of the chamber. The bottoms of these trays or troughs may be
perforated or for some purposes they may be solid.
Each of these trays or troughs is capable of pendulous movement independently
of the others.
As the chains pass up along and over the sprocket wheels in the drying chamber
After the trays or
the trays or troughs retain their normal hanging position.
troughs emerge from the drying chamber they are caused to tip up to discharge
their contents which may be effected by providing them with brackets from each
of which projects a tang or cam in an angular upward direction. These tangs or
cams as the trays or troughs emerge from the drying chamber come into contact with
a stop causing the trays or troughs to successively tilt over and so discharge their
contents.
I prefer not to give a continuous travelling motion to the chains but to give them
an intermittent travelling motion which may be so worked that as the aforesaid stop

page_text: tilts each tray or trough to its inaximum the travelling movement will stop and the
tray or trough be therefore retained in discharging position during which time I may
by any suitable mechanism give it a knock or shake or I may arrange a brush to
rotate or come against the bottom of the tray or trough when it is being tilted and so
facilitate the removal of the contents.
The stop before referred to may be fixed directly to the side of the machine or it
may be on a lever pivoted to the machine enabling the stop to accommodate itself to
any irregularity in the tangs or cams of the trays, the movement of the lever con-
taining the stop being positive that is its amount of play is limited so that it neither
can descend or ascend beyond given points.
I prefer to tilt the trays or troughs in the manner hereinbefore described but I
may employ other means such for instance as a rack and pinion or a cain actuated
by a separate mechanism or I may arrange the stop to operate from underneath the
trays or troughs.
The trays or troughs having been tilted and emptied return to their normal
position and are carried on by the chains to the driving sprocket wheels the said
trays receiving a fresh charge whilst they are passing round the said wheels or at
other convenient place. The charge may be either spread in the trays or troughs
by hand or by a mechanical feeder. The charged trays or troughs then pass down-
wards and reenter the bottom of the drying chamber so that the operation is
continuous. Although I have described the series of trays or troughs as passing in
at the bottom of the chamber and emerging at top and the hot air as entering at
top and passing off at bottom the arrangement may be reversed if desired.
Dated this 28th day of October 1880
J. H. JOHNSON.& Co.,
47, Lincoln's Inn Fields, London, Agents.
COMPLETE SPECIFICATION.
Improvements in Apparatus for Drying Tea Leaves, Coffee, Grain,
or other Produce.
I, WILLIAM JACKSON of Thorn Grove Mannsfield, Aberdeen, North Britain,
Gentleman 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 apparatus for use in drying tea leaves coffee or other
produce.
Hitherto tea leaves and other products have been dried or withered in chambers
provided with endless metallic webs or bands placed in a horizontal superposed
position and carried over rollers or sprocket wheels at each end. The first or upper
web by its movement carried the material spread on it forward till the said
material dropped over the end down on to the second web, on which the said material
was returned, and so on till it reached the bottom band which discharged the dried
material.
I will describe my Invention with reference to the accompanying drawing Figure 1
being a plan and Figure 2 a side elevation of an apparatus constructed according to
iny invention.
My said invention has for its object to provide an arrangement of perforated trays
or troughs a a connected with pitch chains b b (or their equivalents) which will convey
the said trays or troughs a a in a circuitous path from the bottom to the top of the
drying chamber A whilst a current of heated air is caused to pass in a downward
direction through them. Or the air may pass upwards and the passage of the trays
or troughs may be from top to bottom of the chamber. I may create the current of
air by providing the said chamber with an inlet for hot air at the top (or upper
part as for example at o into which the hot air is drawn from the heater C) an
exhaust fan or fans as at D drawing the heated air through an aperture e at the

page_text: bottom of the drying chamber. I may use the ordinary centrifugal fan or fans in
lieu of those illustrated, and draw the air from any other convenient aperture below
the lowest web. Into this chamber I introduce two endless pitch chains (or the
like) 6 of equal length one for each side of the chamber the said pitch chains (or
the like) passing over the sprocket wheels g g and entering at the front end and lower
part of the chamber and passing along near the bottom then turn upwards over
sprocket wheels h h at the back end of the chamber and return parallel to the bottom
part of the chains and again pass upwards over wheels ii and then return to the back
end of the chamber and so on as many times as desired till they emerge at the front
end near the top, where they continue their path to outside the drying chamber
where they pass over driving sprocket wheels at jj and turning downwards they again
enter the lower part of the drying chamber.
At intervals along the pitch chains I suspend trays or troughs aa. This may be
effected by providing the chains with ears to receive the trays or troughs which ears
may also receive stay rods which pass from one side of the machine to the other
that is from the ears on the chain at one side to those on the chain at the other side.
On the ears of the chains (which may be used without the rods) I suspend or
pivot in pendulous fashion the said trays or troughs a a, which are preferably of
a shallow flat bottomed dish shape, in close succession to each other so as to
constitute in effect a web extending from side to side of the chamber. The
bottoms of these trays or troughs may be perforated or for some purposes they
may be solid.
Each of these trays or troughs is capable of pendulous movement independently
of the others.
As the chains pass up along and over the sprocket wheels in the drying chamber
the trays or troughs retain their normal hanging position. After the trays or
troughs emerge from the drying chamber they are caused to tip up to discharge
their contents into a shoot as at x which may be effected by providing them with
brackets from each of which projects a tang or cam k k in an angular upward
direction as shewn in Figure 3. These tangs or cams as the trays or troughs emerge
from the drying chamber come into contact with a stop 2 causing the trays or
troughs to successively tilt over and so discharge their contents.
I prefer not to give a continuous travelling motion to the chains but to give them
an intermittent travelling motion which may be so worked that as the aforesaid
stop tilts each tray or trough to its maximum the travelling movement will stop
and the tray or trough be therefore retained in discharging position during which
time I inay by any suitable mechanism give it a knock or shake or I may arrange
a brush to rotate or come against the bottom of the tray or trough when it is being
tilted and so facilitate the removal of the contents.
This intermittent movement can be effected by driving from the crank disc
the rod which reciprocates the bell crank lever m loose on the axis of the
driving sprocket wheels so that as the said bell crank lever reciprocates the pawl n
is disengaged (by the link p) from its engagement with a toothed wheel on the
shaft of the driving sprocket wheels and moved back during the emptying of each
tray and then is raised to engage, on the return stroke, with the said toothed
wheel to give the intermittent inotion referred to.
The stop may be fixed directly to the side of the machine or it may be on a lever
(as shown in the Drawing) pivotted to the machine enabling the stop to accomodate
itself to any irregularity in the tangs or cams of the trays the movement of the lever
carrying the stop being positive that is its amount of play is limited so that it neither
can descend or ascend beyond given points.
I prefer to tilt the trays or troughs in the manners hereinbefore described but
I may employ other means such for instance as a rack and pinion or a cam actuated
by a separate mechanism or I may arrange the stop to operate from underneath
the trays or troughs.
The tray or troughs having been tilted and emptied return to their normal position

page_text: and are carried on by the chains to the driving sprocket wheels the said trays receiv-
ing a fresh charge whilst they are passing round the said wheels or at other
convenient place for instance by the regulated supply wheel at P. The charge
may be either spread in the trays or troughs by hand or by a mechanical feeder.
The charged trays or troughs then pass downwards and reenter the bottom of the
drying chamber so that the operation is continuous. Although I have described the
series of trays or troughs as passing in at the bottom of the chamber and emerging
at top and the hot air as entering at top and passing off at botton the arrangement
may be reversed if desired. In order to take up slack in the chains the driving
sprocket wheels may be mounted in bearings on levers y held in position by
centered tye rods z passing through eyes on the levers and adjusted and secured by
nuts.
Having now particularly described and ascertained the nature of my said
Invention and in what inanner the same is to be performed I declare that
what I claim is :-
1. In apparatus for drying tea leaves, coffee grain or other produce the com-
bination with a drying chamber of an endless carrier having trays or troughs suspended
therefrom and passing through the said chamber through which hot air is passed
substantially as hereinbefore described.
2. In apparatus for drying tea leaves coffee grain or other produce the combination
with a drying chamber with an air inlet at top or upper part and an air outlet
at bottom or lower part of an endless carrier having trays or troughs suspended
therefrom and passing in at the bottom of the chamber and out at the top of the
chamber substantially as herein before described.
3. In combination with the devices claimed by the preceding claiming clauses
means substantially as described for tilting the trays or troughs for discharging them
of their dried contents.
4. In apparatus for drying tea leaves coffee grain or other produce a conveyer
therefor passing through the drying chamber in one direction and means for causing
acurrentot air to pass through the said chamber in the opposite direction substantially
as herein before described.
5. The general arrangement and combination of parts constituting an apparatus for
drying tea leaves coffee grain or other produce substantially as hereinbefore described
and illustrated in the accompanying Drawings.
T: 1 dow of Tenuary 1800