IMPROVEMENTS IN APPARATUS FOR DRYING TEA LEAF AND OTHER SUBSTANCES
Year: 1879

page_text: LETTERS PATENT to John Norman, of Glasgow, in the County of Lanark,
North Britain, Engineer, for the Invention of "IMPROVEMENTS IN APPARATUS
FOR DRYING TEA LEAF AND OTHER SUBSTANCES."
Scaled the 09-1 Decembar 1870 and dated the 30th June 1879
PROVISIONAL SPECIFICATION left by the said John Norman at the Office of
the Commissioners of Patents on the 30th June 1879.
JOHN NORMAN, of Glasgow, in the County of Lanark, North Britain, Engineer.
"IMPROVEMENTS IN APPARATUS FOR DRYING TEA LEAF AND OTHER SUBSTANCES."
This Invention has for its object to improve the construction and action of
apparatus for drying tea leaf and other substances, and so as to render such
apparatus economical and efficient in use.
In carrying out the Invention there is employed a cylindrical or otherwise shaped
casing of iron, or wood, or other suitable material, which is placed in a position
slightly inclined from the horizontal. The under part of this casing is made semi-
cylindrical and fixed together in sections by castiron frames, these frames being
fitted to an iron plate running the whole length of the machine. The extent of
inclination of the casing may be adjusted by a screw. In or nearly in the axis of
the casing there is placed a tubular shaft, which may be driven at a suitable speed
in any convenient way, and having at suitable distances apart castiron centres or
collars which have curved metal or wooden arms fitted to them. The concave slides
of these curved arms face forwards relatively to the direction of rotation, and metal
sheets or wooden boards are fixed longitudinally upon their outer ends, and so as to
leave a narrow opening between the inner edges of the metal or other sheets and
the tubular shaft. Each arm may have two or more longitudinal lifters fixed to.
curved arms running the whole length of the machine. The tea leaf or other
substances to be dried are filled into a hopper placed at the top of the higher end
of the casing, and by a screw or other suitable means fed into the casing, being
received on the series of concave trays formed by the curved arms of the tubular
shaft, which as they revolve cause the repeated turning over of the tea leaf or other
substances, and from the inclined position of the apparatus the tendency of the tea
leaf is to fall gradually downwards towards the lower end of the apparatus, from

page_text: whence it is discharged into any suitable receptacle. A current of heated air, gas,
or superheated steam is forced by a fan or otherwise into the tubular shaft, from
which it issues from outlets formed conveniently at intervals along its length, these
outlets being so placed as to bring the heated air, gas, or superheated steam into contact
with the tea leaf or other substances to be dried. A gutter is arranged along the
interior of the casing so as to carry off any moisture due to condensation of the
vapor given off during the drying action. The heated air, gas, or superheated steam
may be heated in any convenient manner. The lower or bottom part of the
apparatus is framed of wood or metal, and fitted with doors so as to form a chamber
for the heated air, gas, or superheated steam. Earthenware may be employed for
lining the interior of the casing.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John Norman in the Great Seal Patent Office on the 29th
December 1879.
JOHN NORMAN, of Glasgow, in the County of Lanark, North Britain, Engineer.
"IMPROVEMENTS IN APPARATUS FOR DRYING TEA LEAF AND OTHER SUBSTANCES.'
"
My said Invention has for its object to improve the construction and action of
apparatus for drying tea leaf and other substances, so as to render such apparatus
economical and effective in use.
In carrying out my Invention there is employed a cylindrical or otherwise-shaped
casing of iron or wood or other suitable material, which is placed in a position
slightly inclined from the horizontal. The under part of this casing is made semi-
cylindrical, and is by preference fixed together in sections with castiron supporting
frames. In the axis of the casing, or nearly so, there is placed a tubular shaft which
may be driven at a suitable speed in any convenient way, and having at suitable
distances apart castiron centres or collars which have curved metal or wooden arms
fixed to them. The concave sides of these curved arms face forwards relatively to
the direction of rotation, and long concave trays made of metal sheets or wooden
boards are fixed longitudinally upon them, so as to leave narrow openings between
their inner edges and the tubular shaft. The tea leaf or other substances to be
dried are filled in at the higher end of the casing, being received on the series of con-
cave trays, which as they rotate cause repeated turning over of the tea leaf or other
substances, and from the inclined position of the apparatus the tendency of the tea
leaf is to fall gradually downwards towards the lower end of the apparatus, whence it
is discharged into any suitable receptacle. Currents of heated air, or gas, or super-
heated steam, forced by a fan through heating apparatus, are passed into the casing
so as to act on the tea leaf or other substances to be dried.
And in order that my said Invention and the manner of performing the same
may be properly understood, I hereunto append two Sheets of explanatory Drawings,
to be hereinafter referred to, and representing my improved apparatus for drying

page_text: tea leaf and other substances. In these Drawings the same reference numerals are
used to mark the same or like parts wherever they are repeated.
Figure 1 on Sheet 1 of the accompanying Drawings is a side elevation of my
improved apparatus for drying tea leaf and other substances; Figure 2 on Sheet 2
being a longitudinal vertical section, and Figure 3 a transverse vertical section;
Figure 4 is a horizontal section of air heating apparatus shown in side elevation and
vertical section in Figures 1 and 2.
My improved apparatus comprises a casing 1, 2, formed with its under part 2
semicylindrical, and with a cover or roof 1 having inclined sides and a flat top 3, in
which funnels 4 are provided at suitable distances apart for the escape of the vapors
and gases. The casing 1, 2, is placed in a position slightly inclined from the hori-
zontal. The under part 2 is fixed together in sections with vertical castiron frames
. 5 connected by horizontal frames 6 extending the whole length of the machine. The
frames 5 and casings 1, 2, are supported upon lower castiron frames 7, which are
of graduated sizes, so as to give the desired inclination to the casing. In the axis
of the casing 1, 2, or nearly so, there is placed a tubular shaft 8 carried in bearings
at the ends of the casing 1, 2, and having at one end a bevil wheel 24 in gear
with a bevil pinion on a transverse shaft 27 driven in any convenient way. The
shaft 8 has fixed on it, at suitable distances apart, a number of castiron centres 9,
these centres having fitted to them eight or other convenient number of curved
metal arms 10. The concave sides of these curved arms 10 face forwards relatively
to the direction of rotation, which is indicated by an arrow, and long concave trays
formed by metal sheets 11 are fixed longitudinally upon them so as to leave
narrow openings 12 between the inner edges of the trays 11 and the shaft 8. The
tea leaf or other substances to be dried are filled in at the higher end of the casing,
being delivered into the apparatus by an endless apron 13, carried by two transverse
rollers 14, 15, held in bearings slightly above the shaft 8. The outer roller 15 has
upon its end a pulley for a driving belt from a pulley on the shaft 27. The tea
leaf falls from the endless apron 13 into a cylindrical shell 16 at the end of the
concave trays 11, and is directed by a number of inclined plates 17 upon the ends
of the curved trays 11. The cylindrical casing 16 and plates 17 are best seen in
Figures 5 and 6 on Sheet 2 of the accompanying Drawings, these Figures being
sectional side and front elevations. The concave trays 11 as they rotate cause the
repeated turning over of the tea leaf carried by them, and the tea leaf in thus
turning over approaches the centre and falls through the openings 12 in succession,
the trays 11, which are lowest, preventing the tea leaf from falling upon the under
casing 2, and carrying it upwards again repeatedly. The inclined position of the
apparatus causes the tea leaf to gradually full towards the lower end, whence it is
discharged through an outlet 18, closed by a door 19 into any suitable receptacle.
An automatic arrangement is employed for opening and closing the door 19, and is
shown in front elevation in Figure 7 on Sheet 2 of the accompanying Drawings,
Figures 8 and 9 being vertical and horizontal sections. This door 19, which when
closed, is in an oblique position, is centered near its middle on a spindle, having at
one end a horizontal lever 20. A pin on the middle of the lever 20 projecta into a
slot in one arm 21 of a bell-crank lever 22. A pin 23 on the bevil wheel 24 strikes
the vertical lever 21, and raises the lever 20, thus opening the door 19 each time
that it is brought round by the rotation of the wheel. During its passage through
the apparatus, the tea leaf is subjected to the drying action of currents of heated
air forced into the casing 1, 2, by a fan 25. This fan 25 is driven by a belt from a
pulley on the first motion shaft 26, which shaft 26, also by a belt and pulleys,
drives the shaft 27. The fan 25 forces a current of air into heating apparatus,
which comprises a vertical cylindrical fire box or furnace 28, having above it a
cylindrical combustion chamber 29, crossed by a number of horizontal tubes 30, and
provided with an uptake 31 at its top. The fire box 28 and combustion chamber
29 are enclosed by a cylindrical casing or shell 32, and the air is delivered by the
fan into the lower part 83 of the space between the fire box 28, chamber 29, and
the shell 32. The heated air next passes upwards and through the tubes 30 into a

page_text: space 34 separated by partitions 35, 36, 37, 38, whence it is conveyed by a pipe 39
into a horizontal pipe 40, carried by the frames 5, and extending the length of the
casing 1, 2, of the drying apparatus. From the pipe 40 the heated air is admitted
into the casing 1, 2, of the drying apparatus through branch pipes 41, fitted with
valves for regulating the admission of the heated air by each. I formerly proposed 5
to admit the heated air through the tubular shaft 8, but the arrangement herein-
before described and shown in the accompanying Drawings is preferable, as it
admits of regulating the admission of the heated air into the different parts of the
drying apparatus.
Having thus particularly described my said Invention, and the manner of 1
performing the same, I have to state that I do not restrict myself to the precise
details herein described and delineated, but that what I believe to be novel and
original, and claim as the Invention secured to me by and in terms of the herein-
before in part recited Letters Patent is,-
1. The arranging or combining together of parts of apparatus for drying tea leaf 1
and other substances, substantially in the improved manner hereinbefore described.
2. The combination of concave trays 11, mounted so as to rotate about a slightly
inclined axis, and so as to deliver the substances over their inner edges from one to
the other in succession, substantially as hereinbefore described.
3. The hereinbefore described arrangements for introducing the heated air and 2
regulating its application to the substances being dried.
In witness whereof, I, the said John Norman, have hereunto set my hand
and seal, this Twenty-sixth day of December, in the year of our Lord One
thousand eight hundred and seventy-nine.
Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
JOHN NORMAN. (L.S.)