Year: 1887

page_text: Date of Application, 6th Sept., 1887.
Specification Accepted, 7th Oct., 1887.
Fig. 5, a horizontal section, and
Fig. 6, a longitudinal section of the furnace and air-heating apparatus.
In these drawings the frame of the drier, preferably of brick, is represented by the
letter, A. Secured to this frame are plates, a, which form bearings for the moving
portions of the apparatus.
B, represents tubes attached at each end to the frame, A. These tubes are arranged
in tiers and abreast of each other, the number being governed by the desired capacity
of the drier. Each tube communicates with a passage, b, which connects it at one
end with the adjoining or next upper tube and at the other end with a similar passage
which connects it with the adjoining or next lower tube.
C, represents screw or other conveyors mounted in bearings c, fixed in the frame, A.
These conveyors are so mounted as to play upon the lower surfaces of the tubes, B,
and receive a motion to convey the substances to be dried in the direction indicated
by the arrows. By these conveyors, the substances are carried from the point of
inlet along the tubes to the passages, b, through which they drop upon the conveyor
in the next lower or adjoining tube. Thus, the substances are carried through a great
extent of tube.

page_text: Hot air is admitted at an inlet opening; D, and thence passes through the tubes, B,
and passages, b, in a direction opposite to that in which the substances to be dried
move.
As the hot air is introduced above the discharge opening E, a circular plate, e, is
placed within tube, B, a short distance above the discharge opening to act as a
stuffing-box, so that the entrance of any cold air is prevented.
The hot air, after passing through the tubes and through the substances which are
acted upon by the conveyors, is discharged at an opening, E', and thence passes either
to the chimney or to the open air through a pipe, E2. The hot air thus discharged
and laden with combustible gases eliminated from the substance dried, may be
conducted to the fire-pot of the furnace used, to heat the air and be utilized to increase
the heat.
As the hot air is discharged at a point immediately adjoining the feed-opening, a
circular plate, K', is placed within the tube, B, to cover the conveyor a short distance
from its entrance into the feed hopper, K, and act as a stuffing-box to prevent the
entrance of cold air.
In order that the substance to be treated, shall be acted upon on all sides by hot air,
the passages, F, are provided below and around the tubes or conduit, B, whereby hot
air passing through them heats the exterior of the tubes. The passages for hot air
below and around the different tiers of tubes communicate through the vertical
passages, f.
In fig. 5, of the drawings the upper tier of tubes is shown in preferred form. Here
the tubes taper toward the point at which the substance to be treated is introduced,
the purpose being to economize space by having inlet or feed-hopper box, K, through
which the tubes are supplied, comparatively small, thus rendering the feed easy of
control.
The preferred form of furnace to be used is shown in Fig. 6, where, H, represents
the casing of the furnace and, h, the grate bars.
Cold air is admitted at the opening, P, and, passing through heating-pipes, I, and
through a conducting pipe, i, is admitted in a heated condition at the opening, D,
into the lower tier of the tubes, B, thence passing through the series of tubes, B, to
the outlet, E³.
Hot air, smoke and the products of combustion from the fire-pot, pass through an
opening at, h¹, into the chamber, h³, where they strike the outer surfaces of the
heating pipes, I, and thence escape through the lower smoke passage, 78, to the
chimney in any suitable course. The amount of heat upon the outer surfaces of
the heating pipes is governed by a vertically movable bridge wall, h³, preferably of
fire-brick, and so arranged as to be raised and lowered by a pinion, 74, mounted in
the casing of the furnace in contact with the bridge wall."
Hot air, smoke and other products of combustion also pass through an opening, h³,
from the fire-pot and thence through a conduit to a point F', (fig. 5) where they enter
the upper tier of passage, F, and are thus utilized to heat the outer surfaces of the
conduits, B. The passage, h³, can be closed by a vertically sliding gate bridge-
wall, h, operated by a pinion, h', mounted in the casing of the furnace and meshing
with the gate bridge-wall in such manner that turning the pinion will move the gate
up or down to regulate the size of the passage 5, and thus prevent the scorching of
the substance to be dried.
The shafts of the conveyors are connected by belts or chains, c¹, to a power shaft, G,
from which all of the conveyors receive a motion in such direction as to move the
substances to be dried.
Having now particularly described and ascertained the nature of our said invention
and in what manner the same is to be performed we declare that what we claim is―
1. The combination with a drier, consisting essentially of a series of tubes or
conduits arranged in tiers and communicating in such manner as to form a serpentine
passage for the substance to be dried, conveyors for moving the substance to be
treated through the tubes, a hot air conduit admitting air into the tubes in such a

page_text: manner as to commingle with the substance to be dried and passages arranged
contiguous to the tubes, whereby the exterior of the tubes may be heated, of a furnace
having an air-heating attachment and a flue for the escape of products of combustion,
the air heating attachment communicating with and discharging hot air into the
material to be dried at the lowest tier, and the air passing upward commingling with
the substance in the successive tiers, to the outlet, and in a direction opposed to that
of the direction of the substance to be dried, and the flue carrying off the hot products
of combustion communicating with the passages, arranged contiguous to the tubes at
the upper most tier, whereby the tubes and the material will be more uniformly heated,
substantially as described.
2. In the combination with a hot air tube, the passage, B, containing a conveyor,
by which the material to be dried is fed, such passage having a discharge opening for
material to be dried, at its lower end, provided with a plate, a short distance above to
act as a stuffing-box, so that the entrance of cold air will be prevented, substantially
as described.
3. In the combination with the upper passage, B, containing a conveyor and
provided with a feed opening for material to be dried, and an opening adjacent
thereto for the discharge of hot air, a circular plate, K', within the tube, B, to cover
the conveyor a short distance from its entrance into the feed-hopper, and act as a
stuffing box to prevent the entrance of cold air, substantially as described.
4. In a drier, having tubes arranged in tiers with any desired number of tubes
abreast of each other, the upper tier of tubes made tapering toward the point at
which the material is fed, in combination with a hopper located at the tapering end,
whereby all the tubes abreast may be fed from a single hopper, substantially as
described.
5. The combination with a drying apparatus, of the furnace provided with movable
bridge-walls whereby the amount of heat brought in contact with the substance to
be dried is regulated.
6. In combination with a drying apparatus, the heating apparatus consisting of a
fire-pot provided on each side with moveable walls, the heating tubes, I, and conduits
for conducting the heated air and products of combustion to the drying apparatus,
substantially as described.
2