IMPROVEMENTS IN MECHANICALLY FEEDING FURNACES WITH FUEL, & IN APPARATUS CONNECTED THEREWITHE
Year: 1874

page_text: PROVISIONAL SPECIFICATION left by Edward Bennis at the Office of
the Commissioners of Patents, with his Petition, on the 2nd
October 1874.
I, EDWARD BENNIS, of Limerick, in the County Limerick, in the
Kingdom of Ireland, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN MECHANICALLY FEEDING FURNACES WITH FUEL, & IN
APPARATUS CONNECTED THEREWITHE," to be as follows:-
In the mechanical stoker as originally worked out by Stanley, and
more recently by Dillwyn Smith, and others, great difficulties have been
encountered in running the fans at a high velocity without great wear
and tear and loss of power, and also in adjusting them to throw the fuel
evenly over the surface of the fire. No apparatus so far introduced for
using large coal in the machine has hitherto answered well; it is to
overcome or obviate these difficulties that my Invention is designed.
In place of the usual crushing apparatus I make the lower part of the
hopper of cast iron or other strong material, open in front and firmly
braced to the boiler behind. The back of this lower part I prefer to
make sloping with its lower edge nearer the boiler than the upper one;

page_text: the lower edge resting on what I call the "shovel box," and corre-
sponding to the fan box in the Stanley machine. The said lower part
slightly chambers out for a few inches above the box, forming a recess
in which I generally place a moveable partition to be hereafter described.
Above this recess I cast or otherwise fix on a series of cutters, ridges,
obtuse blades, horizontal ridges or teeth, pointing downwards to some
extent. The two sides of the lower part of the hopper are parallel or
only very gently inclined and plane surfaced. The front of said lower
part of the hopper I make chambered out at the bottom, and its surface
in all other respects corresponding approximately to that of the back
that is armed with ridges or teeth, but instead of being firmly fixed its
lower extremity slides on the shovel box aforesaid, and its centre is
firmly pivotted by means of two excentrics to the main horizontal shaft
running parallel with the face of the boiler and working in bearings on
aforesaid box. The back of the lower part of the hopper and the
moveable front which together form the crushing apparatus, approach
near each other just above the recessed part of the bottom, but are much
wider apart at the top where the hopper proper commences, and this
distance can be regulated if desirable by making the excentric rods
adjustable. In the recessed part above mentioned is a moveable
partition extending from side to side and adjustable by studs in its ends,
projecting through slotts in the sides of the hopper, or any other
convenient manner, to regulate the quantity of fuel containable in the
recess and consequently the amount of feed.
Below the crushing and regulating apparatus is a rectangular "shovel
box" open to the fire, and which can or need not be hopper shaped
towards the fire. This box is firmly fixed to the furnace front like the
fan box of an ordinary Dillwyn Smith machine, and has the usual
opening below the crushing apparatus to allow the coal to fall through
into it. This "shovel box" is entirely open in front also. In the box I
place what I call the "shovel," consisting of a vertical plate stretching
entirely across the box, flat, curved, or irregularly shaped, as may be
found most desirable. It has a broad horizontal flange on the top on
the side furthest from the furnace, and usually another on the bottom on
the side next the fire. In or near the centre of the vertical portion
of the shovel I place a pin or stud vertically called the "swivelling pin,”
and usually put vertical flanges on the ends of the vertical plate of the
shovel on both sides of the same, and rounded to an arc of a circlo

page_text: ·having the swivelling pin for a centre. Connected to the shovel by the
aforesaid stud and swivelling horizontally on same, I place a link armed
on its upper surface with teeth like an ordinary rack, but pointed and
with its other end fastened in any convenient manner to a spring or
substitute therefor (as hereafter to be explained). On the main shaft
between the two excentrics actuating the crushing apparatus I place a
pinion with pointed teeth on a portion of its circumference to gear into
the rack aforesaid; or instead of this arrangement I may use smooth or
grooved friction surfaces alterable at pleasure. I also arrange suitable
mechanism for regulating the angle at which the shovel stands to the
link.
The wrought-iron hopper placed over the crushing apparatus has a
jointed flap in front, hanging against the moveable jaw of the crushing
apparatus, so as to accommodate itself to the motion of the latter. The
spring can be of any suitable form or can be a horizontal beam having a
cylinder and piston or other air or steam cushion at each end. In some
cases both the jaw of the crushing apparatus and the shovel could bo
worked direct by steam or other pressure on pistons in cylinders.
The manner of working is as follows:-The hopper being filled
with fuel the latter descends into the crushing apparatus, and as the
jaws are brought nearer together by the excentric, a part gets crushed.
When the jaws retract the stuff falls into the recess, filling it to the
partition, but is stopped from falling any further by the upper flange of
the shovel. As the jaws again contract and hold the fuel as it were in a
vice the pinion working on the racked link draws the flange of the shovel
from under the recess, and the fuel falls on to the lower flange of the
shovel and on to the floor of the shovel box. Just before the jaws begin
to retract again, the segmental pinion disengages from the rack, and the
shovel rebounding after being placed in compression by the rack sends
the stuff lying on the lower flange of the shovel and on the shovel box
bottom flying into the fire. The spring can be regulated in any
convenient manner as regards extent of compression. Occasionally
instead of the above description of crusher, especially when the fuel is of
a soft variety, I insert one or more plungers or shears at the base of the
hopper (worked by excentrics as in the last plan or other contrivance),
which crushing into the fuel separates the stuff in the recess from that
above shearing any large pieces of coal between their edges and a blade
or cutter fixed to the back of the hopper. The edges of these shears can

page_text: be of any desirable form, as for instance a series of triangular points.
In this case the ribbed back and moveable jaw are dispensed with, and
the wrought-iron hopper is brought much lower down.
be of any desirable form, as for instance a series of triangular points.
In this case the ribbed back and moveable jaw are dispensed with, and
the wrought-iron hopper is brought much lower down.
My shovel apparatus can also be applied to any of the well known
forms of crushing apparatus used in mechanical stoking.