IMPROVEMENTS IN TEA DRYING MACHINES
Year: 1887

page_text: Date of Application, 22nd June, 1887
Complete Left, 20th Jan., 1888
Complete Accepted, 16th Mar., 1888
ALFRED HORATIO BELL SHARPE Draughtsman Tattershall Villas Lea Road
Gainsborough Lincolnshire I do hereby declare the nature of my invention for
IMPROVEMENTS IN TEA DRYING MACHINES to be as follows:-
The Improvements herein refered to consist of an arrangement of perforated trays
or flaps at different levels (which constitute the different drying surfaces) revolving
on a vertical shaft, whilst a current of heated air is drawn rapidly through the
perforations by an exhaust fan affixed to the top of Machine; and in allowing the leaf
to pass from one drying surface to another without having to be taken out of the
Drying Machine.
The leaves are conveyed into the top tray, which consists of a number of perforated
flaps, through the hopper; and after being carried through one revolution are let fall
onto the next drying surface, from whence they are again let fall on to the next, and
so on until they pass out at the bottom.
The Machine may be driven by hand or from a line shafting by belt and pulley.
The accompanying drawings aided by the following description will fully explain
the method adopted for accomplishing this object.
(Fig. 1) is a longitudinal section embodying my improvements, for which the air
required is heated by passing through a number of small tubes contained in a vertical
steam dome; which steam dome is fixed inside the bottom of the machine, and feed
from a Vertical Steam Boiler placed alongside.
(Fig. 2) is a sectional plan of Tea Drying Machine showing an arrangement of
perforated Trays, which consist of a number of hinged flaps.
(Fig. 3) is a longitudinal section embodying my improvements, for which the air
required is heated by passing through a number of vertical cast iron tubes, the stove
being so arranged that no smoke, fumes, or gases, from the combustion chamber can
come in contact with the drying leaf.
(Fig. 4) is an enlarged section of the machine, showing perforated hinged flap let
down on passing a certain point in its revolution, and depositing the leaf on to the
next drying surface.
it
(Fig. 5) is a plan, Driving may be effected by putting a strap over the pulleys, or
may be turned by handles as illustrated on the drawing.
Inno 99nd 1887

page_text: improvements in Tea Drying Machines.
I, ALFRED HORATIO BELL SHARPE, late of Tattershall Villas, Lea Road, Gains-
borough, but now of Lincoln, in the County of Lincoln, Engineer, do hereby declare
the nature of the said 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 certain improvements in or applicable to machines or
apparatus for drying leaves of the tea plant, the same being also applicable for drying
other analogous substances, the special objects of the Invention being to simplify and
cheapen the construction of the apparatus, to improve the method of operation in
drying the leaves in such a manner as that it may be more expeditiously and
advantageously effected than as hitherto, to economise and use to the best advantage
the drying agent ; and to lessen the manual labour necessary in carrying out the said
operation.
The Invention consists essentially in constructing the apparatus with one or more
series (each of any required number) of superposed perforated trays which are rotated
by suitable means within a closed chamber or chambers, and upon the upper one of
which trays, the tea leaves are automatically fed by adjustable feeding devices, and
from which and successively from the consecutive lower trays, after being duly
operated upon in each tray, the tea is automatically transferred to the tray next below
and so on until the series thereof have been traversed by the tea and the dried leaves
escape from the machine into a suitable receptacle; and in effecting the drying
operation in apparatus thus constructed or adapted by the agency of heated air drawn
by an exhaust fan rapidly through the drying chamber and the perforations of the
trays upon which the tea is supported in the reverse direction of the travel of the tea,
so that the latter will be at first warmed and gradually heated and dried before it
escapes from the machine.
By such improved means the present necessity of opening the drying chamber to
withdraw drying trays or to remove the tea leaves from one tray to another (and
which is detrimental in permitting of the escape and waste of the heating agent) is
avoided, and all manual manipulation of the leaves is avoided between the time the
same are put into the feeding hopper of the apparatus to be dried and the time they
emerge from the apparatus in such condition as required.
The air to be used in drying the tea leaves may be heated to the required
temperature by any suitable means so constructed applied and used as that the air in
being heated will not be vitiated by any other products of such heating apparatus.
The accompanying drawings represent several modifications of apparatus con-
structed in accordance with the said Invention, the same or equivalent parts being
indicated by the same reference numeral.
Fig. 1. is a sectional elevation; Fig. 2. an elevation; Fig. 3. a sectional plan view,
and Fig. 4, an enlarged plan view of a modification in which the apparatus is con-
structed with one series of four trays, 1, and in which the means of heating the air by

page_text: which the tea leaves are dried consists of a connected steam boiler, 2, and of a closed
steam dome, 3, arranged within a cylindrical drying chamber, 4, and under the series
of trays, 1. The steam is led by the pipe, 5, to within the steam dome, 3, which is
traversed by a series of vertical open ended pipes or tubes, 6, through which the air
passes upwardly into the chamber, 4, being heated in its passage by the steam in the
dome, 3, surrounding the tubes, 6. 7, represents a connection under the control of a
tap, 8, for letting off the water of condensation from the dome, 3.
In this modification the trays, 1, are attached to and revolve with a tubular boss, 9,
fast on the upright shaft, 10, which has its bearings in an adjustable foot-step, 11, and
in the top of the chamber as at, 12, the outer rims of the trays resting upon and being
supported by flat rings, 13, carried by inwardly projecting brackets, 58, attached to
the sides of the casing or chamber, 4, see Fig. 6, hereinafter referred to.
The construction of the trays, 1, is more clearly shown in Figs. 5, and, 6; which
are respectively an enlarged sectional plan view of the drying chamber, 4, and a still
further enlarged sectional elevation of part thereof. The bottom of each tray consists
of a series of radiating segmental flaps, 14, which may be made of perforated sheet-
metal or of woven wire, and are hinged at, 15, to the said boss, 9, and to a circum-
scribing ring, 16, which is bolted to the outer rim of the tray and is supported by
radiating stay rods, 17, connected to the boss, 9, and which are provided with rollers
or wheels, 18, which run along the ring, 13, and permit of the tray being rotated
within the chamber with the minimum of friction. The flaps, 14, aro also normally
supported by the ring, 13, and by an opposite ring, 19, which is independent of but
encircles the boss, 9, and is also supported by the brackets, 58, but at any desired
part of the circuit opposite parts of the rings, 13, and, 19, are cut away, as at, 20,
which causes the flaps as they consecutively arrive at such part in each revolution, to
fall about their hinges, 15, and precipitate the tea leaves supported thereon on to the
tray next beneath, after which the flap is restored to its normal position by the
continued rotation of the tray causing it to catch against the edges of the rings, 13, 19;
21, represents closed doorways made in the casing of the chamber, 4, and through
some of which the nuts and parts of the tray can be got at for adjustment or for any
other purpose if required, and through others of which the flaps, 14, can be got at
for renewal or replacement if required."
In the modification represented in Figs. 1, and, 2; the shaft, 10, is represented as
rotated by means of a worm wheel, 22, keyed thereon, and a worm, 23, on a shaft, 24,
which is supported by brackets, 25, and may be actuated by hand wheels, 26, or
otherwise, as hereinafter referred to.
27, represents the fan by the rotation of which the heated drying air is drawn
through the trays and drying chamber and from the latter through chambers, 28, into
opposite eyes, 29, of the fan, from the periphery of which it escapes. The fan may
be driven by a belt, 30, from a pulley, 31, on the shaft, 24, or its shaft, 32, may be
fitted with fast and loose pulleys, 33, 34, and driven by a belt, 35, from any convenient
line shafting, and in such case the shaft, 24, may be driven from the shaft, 32, by the
strap, 30.
36. represents the feeding hopper which is provided with a feeding flap, 37, which
can be set at any position required so as to permit of the feed of tea leaves being
adjusted according to the speed of rotation of the trays or otherwise as required, the
flap being connected by a rod, 38, to a pinned disc, 39, on the fan shaft, 32, and
receiving a kicking feeding motion therefrom.--40, represents the discharge outlet
duct where the dried tea leaves escape into any suitable receptacle, 41.
Fig. 7, represents a modification in which the air admitted to the chamber, 4, for
drying the tea leaves is heated by a multitubular hot air furnace in which the
air-heating tubes are vertically disposed.
In Figs. 8, to, 13, the tea drying chamber is represented as constructed immediately
above a multitubular air beating stove in which the air heating tubes are horizontally
disposed. The arrangement of the drying trays illustrated in the sectional elevation,
Fig. 8, (of which, Fig. 9, is an end elevation), is substantially the same as that herein-
before described with reference to Fig. 1. Fig. 10, represents, in elevation, a

page_text: duplicate construction of the apparatus represented in Fig. 9, there being two series
of drying trays rotating on separate shafts, 10, within a common drying chamber.
Fig. 11, represents, in elevation, a triplicate construction of such apparatus, there
being three series of drying trays rotating on three separate shafts, 10, within a
common drying chamber; and Fig. 12, represents, in elevation, a quadruplicate
construction of such apparatus, there being four series of drying trays rotating on
four separate shafts, 10, within a common drying chamber. In each of the modi-
fications illustrated in Figs. 8, to, 13, the hot air from the furnace is led into the
chamber, 4, by a duct or ducts, 46, opening into the casing immediately beneath the
series or columns of drying trays.
47. in Figs. 10, to 12, represents a doorway by means of which access can be
obtained to the interior of the chamber, 4. In such modifications, the casing of the
chamber, 4, may be made to conform in sectional plan to the contour of the adjacent
series of trays to cause all of the heated air to pass through the trays, or the same
object may be obtained when the casing of the chamber is formed with flat sides by
adapting or providing the brackets, 58, with sheet metal for filling up any space
between the said rings, 13, and the casing, 4, at the level of each series of trays.
In the modification represented in Fig. 13, the shaft, 10, is stationary, and extended
sleeves of the boss, 9, upon connection with which the said trays depend for their
rotation, respectively rest upon the footstep, 11, and are continued up through the top
bearing, 12.
As hereinbefore referred to, the rotating parts of the apparatus may be actuated by
other means than those hereinbefore described, with reference to Figs. 1, 2, and, 4.
A suitable arrangement by which the same may be driven by gearing is illustrated in
plan view in Fig. 14, (as also in Figs. 8, to, 13,) in which the shaft, or each shaft, 10,
(or in Fig. 13, the top sleeve extension of the boss, 9,) projects through the top
bearing, 12, and has keyed thereon a crown bevel wheel, 22, in gear with a pinion, 23,
on a shaft or common shaft, 24, supported in bearings, 25, and which shaft is actuated
from the fan shaft, 32, (driven from line shafting as aforesaid) by the connections
shown, consisting of the strap passing around the pulleys, 48, 49, the latter being on
a shaft, 50, which is supported by bearings, 51, and is provided with a toothed
pinion, 52, which engages with a spur wheel, 53, on a shaft, 54, supported in
brackets, 55, and on the opposite end of which is a toothed pinion, 57, which engages
with a spur wheel, 31, on the said shaft, 24. The speed of rotation of the trays
relatively to that of the fan can be regulated as required by shifting the belt, 30, on
the pulleys, 48, 49. The adjustable flap, 37, of the feeding hopper is regulated as
hereinbefore described, by a rod, 38, connected to a pinned disc, 39, on the shaft, 50.
And Fig. 15. represents a modification in which concentric series of drying trays
may be used, the flaps, 14, thereof being respectively supported by the rings, 13,
and, 19, and by an intermediate ring, 59, also supported by the said stay-rods, 17,
the trays otherwise being constructed and arranged substantially as hereinbefore
described.
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 improved construction and arrangement of machines for drying the leaves
and other analogous substances substantially as hereinbefore described with reference
to the several Figures of the accompanying drawings.
2. The construction of such drying apparatus with one or more series of superposed
trays rotating within a closed casing or drying chamber and formed with hinged
segmental perforated bottom flaps adapted to fall about their hinged connections at
a certain part at each revolution for the purpose stated, in combination with means
for supplying and regulating the supply of tea leaves to the trays, and for rotating
the said series of trays, and with means for supplying heated air to the said chamber
and for drawing such air upwardly through the drying chamber and through the said
perforations of the drying trays substantially as hereinbefore described.

page_text: 3. The construction of rotating trays for use in such drying apparatus in the
manner hereinbefore stated with radiating segmental perforated hinged flap bottoms
operating substantially in the manner hereinbefore described with especial reference
to Figs. 5, 6, and, 15, of the accompanying drawings.
4. The application to apparatus for drying tea leaves or analogous substances, of
one or more series of superposed trays constructed and operating substantially in the
improved manner herein before described.
1000
DAY, DAVIES & HUNT,
321, High Holborn, London, W.C.,
Agents for the Applicant.