IMPROVEMENTS IN. DRYING TEA AND IN THE APPARATUS EMPLOYED THEREIN
Year: 1877

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields, in the
County of Middlesex, Gentleman, for the Invention of "IMPROVEMENTS IN.
DRYING TEA AND IN THE APPARATUS EMPLOYED THEREIN." A communica-
tion from abroad by John Charles Allen, of Cachar, India, Tea Planter.
Sealed the 22nd January 1878, and dated the 14th November 1877.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson at the
Office of the Commissioners of Patents on the 14th November 1877.
"
JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman. IMPROVEMENTS IN DRYING TEA AND IN THE APPARATUS EMPLOYED
THEREIN." A communication from abroad by John Charles Allen, of Cachar, India,
Tea Planter.
This Invention relates to the drying of tea leaves after they have been rolled, and
consists of a peculiar construction, arrangement, and combination of apparatus for
performing that operation by the agency of heated air, either employed alone or in
conjunction with charcoal fumes.
In carrying out this Invention it is proposed to employ a drying oven or chamber
(of thin sheet iron or other suitable material), in which there is enclosed a revolving
wheel fast on a shaft extending through the side or sides of the oven or chamber,
and carrying on the exterior a pulley for receiving motion, which wheel is formed
with a suitable number of blades or pallets for the reception of removable trays for
containing the tea to be dried, and also carries hinged doors for covering the said
trays when in position so as to retain the tea therein.
The oven or chamber is provided with openings, one situate by preference near"
the bottom, for the admission of heated air, another situate by preference near the
top, for the exit of damp air, a third (closed by a door hinged at the bottom and
secured by a clasp at the top), for the introduction and removal of the trays, and a
fourth fitted with a drawer for the reception of any tea which may accidentally fall
from the trays, and which may be removed by the withdrawal of the drawer, the
I Price BdI

page_text: said door and drawer in their normal position forming with the oven or chamber an
air-tight closure.
The trays for containing the tea, which consist of skeleton frames covered with
wire netting, are first filled and then introduced by the door before mentioned into
the interior of the oven or chamber, and slid one on to each of the blades or
pallets of the wheel, provided with suitable bars or supports for their reception and
for securing them in position, after which the tray doors, also formed of wire
netting, are closed down upon the trays so as to retain the tea therein, each door
being fitted with cross bars carrying spikes for preventing the accumulation of the
tea in any one place during the revolution of the wheel. Motion is then. imparted
to the pulley so as to cause the wheel to revolve slowly, and heated air being also
simultaneously introduced into the oven or chamber by means of a fan or blower
driven in connection with the wheel; or otherwise, the tea contained in the trays is
dried under the action of the heated air, the circulation of which is promoted, whilst
at the same time the tea is automatically turned over by reason of the slow rotatory
motion of the wheel.
When the operation of drying is completed the apparatus is stopped and the
trays are withdrawn and replaced by others containing a fresh supply of tea to be
dried, after which the apparatus is again set in motion, and so on in succession.
The apparatus may be driven from a neighbouring rolling machine, if desired.
The pipe which conducts the heated air from the fan or blower to the drying oven
or chamber may be coiled round the furnace for heating the air.
"
When charcoal fumes are employed in conjunction with heated air an air pump is
substituted for the fan or blower, and the drying oven or chamber is placed between
the furnace and the air pump; the heated air entering the pipes immediately over a
charcoal fire, so that the fumes are drawn through the oven or chamber together
with the heated air. In this case the oven or chamber is made to close up air-
tight.
By means of this Invention the whole of the tea contained in the apparatus is
uniformly and rapidly dried with the expenditure of a minimum of labor and
motive power, and without the liability of waste, and of the burning or smoking of
the tea, which frequently takes place in the operation of drying by the ordinary
means, whilst at the same time these results are obtained by the use of apparatus
which is cheap in first cost, compact, of great simplicity, economical in construction,
and not liable to put out of order. As moreover heated air may be used alone in.
the said apparatus the attendant disadvantages of use of charcoal, viz., extra
expense and labour, excessive heat in the tea houses, and noxious fumes are thereby
obviated.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Henry Johnson in the Great Seal Patent Office on the 16th
April 1878.
"
JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman. IMPROVEMENTS IN DRYING TEA AND IN THE APPARATUS EMPLOYED
THEREIN." A communication from abroad by John Charles Allen, of Cachar, India,
Tea Planter.
The said Invention relates to the drying of tea leaves after they have been rolled
or curled, and it consists in the employment of a revolving wheel constructed and
fitted in the manner herein-after described for containing the tea, and enclosed in
an oven or chamber, the drying being effected by the agency of heated air, either
used alone or in conjunction with charcoal fumes.
'
And in order that the said Invention may be fully understood I shall now
proceed more particularly to describe the same, and for that purpose shall refer
to the several Figures on the annexed Sheet of Drawings, the same letters of
reference indicating corresponding parts in all the Figures.
Figure 1 of the accompanying Drawings represents a sectional elevation of a
drying apparatus, complete, constructed according to the said Invention.
Figure 2 represents a plan drawn to a larger scale of a segment of the wheel, and
Figure 3 is a corresponding sectional elevation of the same, with one of the hinged
doors herein-after referred to applied thereto, the said door being shewn open.
Figures 4 and 5 represent respectively a plan and longitudinal section of one of
the trays herein-after referred to.
Figure 6 represents a plan of the under side of the hinged door.
And Figure 7 represents an edge view of the boss, and a segment of the wheel,
with the tray in its place and the hinged door closed.
The Figures 4, 5, 6, and 7 are drawn to the same scale as Figures 2 and 3.
A is the drying oven or chamber (of thin sheet iron or other suitable material),
in which there is enclosed the revolving wheel B, fast on a shaft C, extending
through the side or sides of the oven or chamber, and carrying on the exterior or
pulley D for receiving motion. The wheel B is formed with a suitable number of
blades or pallets B', each consisting of arms a connected by cross bars b, b, (see
Figures 2 and 3) for the reception of removable trays E (Figures 4 and 5) for con-
taining the tea to be dried, and also carries hinged doors F (one of which is shewn
detached in Figure 6), for covering the said trays when in position so as to retain
the tea therein.
The trays E consist of skeleton frames covered with wire netting, and the tray
doors F are also formed of wire netting, and are moreover provided with spikes b¹
(see Figures 3, 6, and 7), for preventing the accumulation of the tea in any one place
during the motion of the wheel.
The oven or chamber is provided with an opening c, situate by preference near
the bottom, as shewn, for the admission of heated air, with another opening d,
situate by preference near the top, as shewn, for the exit of damp air, with a third
opening e (closed by a door e', hinged at the bottom, and secured by a clasp at the
top), for the introduction and removal of the trays E, and with a fourth opening f
fitted with a drawer f for the reception of any tea which may accidentally fall from
the trays, and which may be removed by the withdrawal of the drawer, the said
door e and drawer f' in their normal position forming with the oven or chamber A
an air-tight closure.
The apparatus operates in the following manner:-
:- The trays E for containing
the tea are first filled, and then introduced by the door e¹ into the interior of
the oven or chamber A, and slid one on to each of the blades of pallets B¹ of
the wheel B, after which the tray doors F are closed down upon the trays so
as to retain the tea therein, and the door e' is securely closed. Motion is then

page_text: imparted to the pulley D so as to cause the wheel B to revolve slowly, and
heated air is also simultaneously introduced into the oven or chamber A through
a pipe g by means of a fan or blower G either driven by a belt in con-
nection with the wheel, as shewn, or otherwise. The tea contained in the trays
is thus dried under the action of the heated air, the circulation of which is
promoted, whilst at the same time the tea is automatically turned over by
reason of the slow rotatory motion of the wheel.
When the operation of drying is completed the apparatus is stopped, and the
trays are withdrawn and replaced by others containing a fresh supply of tea to be
dried, after which the apparatus is again set in motion, and so on in succession.
The apparatus may be driven from a neighbouring rolling machine if desired.
The air supplied from the fan or blower G to the drying oven or chamber A is
heated by a furnace H, the conducting pipo g being coiled round the said furnace, or
the air may be heated in any other convenient manner.
When charcoal fumes are employed in conjunction with heated air an air pump
is substituted for the fan or blower, and the drying oven, or chamber is placed
between the furnace and the air pump, the heated air entering the pipes immediately
over a charcoal fire, so that the fumes are drawn through the oven or chamber
together with the heated air. In this case the oven or chamber is made to close up
air-tight.
By means of the said Invention the whole of the tea contained in the apparatus
is uniformly and rapidly dried with the expenditure of a minimum of labor and
motive power, and without the liability of waste and of the burning or smoking of
the tea, which frequently takes place in the operation of drying by the ordinary
means, whilst at the same time these results are obtained by the use of apparatus
which is cheap in first cost, compact, of great simplicity, economical in construction,
and not liable to be put out of order. When, moreover, heated air is used alone in
the said apparatus, as before mentioned, the attendant disadvantages of the use of
charcoal, videlicet, extra expence and labour, excessive heat in the tea houses, and
noxious fumes are thereby obviated.
Having now described and particularly ascertained the nature of the said
Invention and the manner in which the same is or may be used or carried into
effect, I would observe in conclusion that what I consider to be novel and original,
and therefore claim as the Invention secured to me by the herein-before in part
recited Letters Patent is, the application and use to and in the drying of tea of a
revolving wheel enclosed in an oven or chamber, and constructed and fitted sub-
stantially as herein set forth, the drying being effected by the agency of heated air,
either used alone or in conjunction with other drying agents, substantially as
herein-before described.
In witness whereof, I, the said John Henry Johnson, have to this my
Specification set my hand and seal, the Sixteenth day of April, One thousand
eight hundred and seventy-eight.
J. HENRY JOHNSON. (L.S.)