IMPROVEMENTS IN MACHINERY AND APPARATUS FOR CHARGING AND DISCHARGING GAS RETORTS
Year: 1872

page_text: PROVISIONAL SPECIFICATION left by William Mann at the Office
of the Commissioners of Patents, with his Petition, on the 24th
December 1872.
I, WILLIAM MANN, of the Gas Works, Dorset Street, in the City of
London, Gas Engineer, do hereby declare the nature of the said.
Invention for "IMPROVEMENTS IN MACHINERY AND APPARATUS FOR CHARGING
AND DISCHARGING GAS RETORTS," to be as follows :-
The object of this Invention is to afford means whereby the manual
labour now employed in charging and drawing gas retorts may be
greatly reduced. With this view a steam or other suitable power engine
is placed upon a travelling bed or frame, so constructed that it may be
moved along to the right or left in front of the retort benches as
occasion may require. Upon the bed or horizontal frame, a vertical
frame is built; this frame serves to support the rakes, while another
vertical frame of similar construction upholds the scoops. Both the
scoops and rakes are capable of being raised or lowered to adapt them to
the use of retorts of varying height.
Machines are already made answering to this general description, and
the machine I propose to construct is not novel in its entirety, but the

page_text: particular arrangement and details of many of its parts are new and
constitute this Invention.
The engine power before referred to is in this Invention applied not
only for the purposes before stated, but for the production of a vacuum
used to actuate the various parts of the machine to which it may be
applicable.
The whole of the machinery may be erected upon a bed plate or
general frame, but I prefer to mount the charging and discharging
machinery in separate frames with an engine to each, so as to make
them independent of cach other."
The apparatus for charging the scoop with coal previous to its
introduction to the retort, consists of an elevator and accessories of
peculiar construction, of which the following is a description. A
receptacle for coals is attached to the bottom part or bed of the machine;
in this receptacle is placed a wheel or drum, and on or near the top of
the machine a corresponding wheel or drum is situated. Around these
two drums are stretched two endless pitch chains to which are fixed a
number of buckets. The buckets are fastened to each of the chains by
their lower ends, and are kept in their place while dipping the coal and
while ascending, by an ordinary chain or wire rope that goes round them
all, and over a wheel or wheels set over the upper chain drum. As each
bucket arrives at the top it does not follow the inclination of the links
and at once upset the coals, but passes on, being retained in an upright
position by a spring, lever, or slot, until it has attained a certain point
when it is suddenly tilted and the coals contained in it are thereby
projected into a hopper.
The hopper just referred to serves to supply the coal to a horizontal
case of about the same length as the scoop, and into which the coal is
drawn by means of a screw, the case being of such a capacity as to hold
about one charge. When the case is filled its bottom is opened, or a
large slot along its under side is uncovered, when the coal falls down a
shoot into the scoop, the shoot being so arranged as to adapt it to feed
the scoop whether it be at a low or high clevation. Should the coal
supplying screw run so fast as to fill the case before the scoop is ready
for it, an overflow lets the surplus coal into a small screw case or inclined
passage, and returns it to the coal receptacle at the bottom of the
machine, but should it be preferred to stop the screw when the case is

page_text: full I arrange a sliding end to the screw case that will push out when
the case is full of coal, and by suitable levers or their equivalents stop
the scew.
The hopper into which the coals are thrown by the elevator, is so
constructed that when full the weight or force of the coal therein causes
a preponderence or movement of the hopper or some of its parts in such
a manner as to act on levers or other suitable mechanism, so as to throw
out the gear that drives the clevator and thus stop it. When the
weight or force of coal has been removed by reason of the screw filling
its case, the parts that have preponderated or moved, return to their
normal position and throw in the gear which again puts the elevator
in motion.
Another method of preventing the coal from overflowing the hopper
consists in placing within the hopper a deeply fluted roller attached
to a spindle which passes through the sides of the hopper, and projects
considerably on one side. A scrow is formed on the projecting spindle
and upon it is screwed a rigger, over which a band passes which causes
it and the roller to revolve. So long as the coal in the hopper does
not reach such a height as to interfere with the freo revolution of the
fluted roller, the buckets will continue to throw coal into the hopper,
but so soon as the revolution of the roller is stopped the rigger will
begin to run back upon the screw until it compresses a spring, acts
upon a lever, or causes the band to pass on to a loose rigger, and thus
stop the further movement of the elevator.
Elevators have been made for the purpose of conveying coal to the top
of charging machines before, but they have been arranged in an inclined
position, whereas I prefer to make mine vertical. The method of
attaching my buckets to the pitch chains, the means adopted for
retaining them in an upright position, the manner in which they are
tilted, the peculiar construction of screw case, and the arrangement
for making the shoot suitable for filling the scoop at various heights,
are all new.
As before stated, I prefer to mount the charging scoop or scoops in a
frame independent of the drawing machine, and on it place the traversing
5 gear as well as the apparatus for actuating the scoops. This can be done
by pitch or other chains by ordinary gear or by a combination of both.
It may also be effected by pressure of the atmosphere induced by
compression or exhaustion, the clastic force of steam or vacuum formed

page_text: thereby. The construction of the scoop is both novel and peculiar. It
consists of two parts divided along its bottom cach-part being hung to a
horizontal shaft or bar which may be hollow so as to admit of the intro-
duction of water, and forms a part of the scoop and enters the retort with
it whenever the scoop is inserted. On or both sides of the scoop is
stretched over suitable pullics an endless chain or wire rope to the upper.
layer of which the rear end of the scoop is attached by clips that may.
be made self-acting or otherwise. The chain or chains, being put in
motion the scoop which is assumed to have received a charge of coal is
moved forward until it has reached the requisite distance in the retort
when a piece of apparatus, say a spring, a chain drawn tight at the right
moment, the application of a pressure or vacuum throws the scoop open
and thereby distributes the coal right and left in a semicircular or
crescent shaped layer in the retort. On the frame in the rear of the
scoop is placed a vertical pipe or barrel closed at the top and fitted with
a piston and rod, the lower part of the rod having attached to it a chain"
or wire rope which is fixed to the back end of the scoop. When the
power is applied to the endless chain before mentioned, the scoop moves.
forward and at the same time draws with it the chain attached to tho
piston, thereby causing a vacuum in the barrel, the vacuum being
increased as the scoop proceeds and until it has reached its full distance
in the retort. The coal having been discharged the scoop is released
from the chain or chains which carried it forward, whereupon the scoop
is quickly drawn back by the atmospheric pressure acting upon the piston
in the barrel. The forward movement of the scoop thus induces the
power to bring it back again ready to receive the next charge of coal.
The same effect may be produced by making a connection between
the piston and a chamber in which a vacuum is induced by the steam
power before referred to. The clips may again be applied to the forward
chain and the same motions repeated whenever the retorts are to be
charged.
The construction of a single scoop in two parts, and the opening of its
parts by the action of such a spring or other contrivance as is before
described, and the manner and direction in which my scoop is opened,
thereby distributing the coal in the retort in a more suitable manner for
carbonization is novel and forms part of my Invention.
The rake bit or head has an axial motion to be used if found
necessary for cutting into the coke or spent charge, and to assist in

page_text: obtaining a better hold of the coke. The rake bar which is made solid
or hollow, if preferred, to allow of the introduction of water is furnished
with one or more subordinate bits which will bite more or less into the
coke, and enable the rake to do its work more effectively. The rake
head has a folding back and a projecting forward motion for the same
purpose, and when passed into the retort the whole or only part of its
length, and has obtained full hold of the coke, it may be withdrawn by
impulsions or by one steady pull, or a combination of both if found more
suitable, for the material to be discharged, the application of a vacuum
to produce the requisite motions being employed if found desirable.
A rake with a projecting and folding head is no novelty, but the con-
struction of it so as to admit of an axial motion and the subordinate bits
as described are new. The application of a vacuum is also new.
An implement something like a scoop or semi-rotative cutter, or if
preferred a sort of bar shovel is also provided to assist the rako in
removing the charge, and is intended to be applied to or thrust in under
the coke about the same time that the rake is inserted, and to be drawn
out with it. The intended use of these inplements which are new is to
break up the coke at or near the mouth piece where the coal is in a
fused state, and not fully coked. It is to be observed however that is
not requisite that this cutter scoop or shovel should go in the whole
length of the charge, nor is it always necessary to use such an implement
at all.