IMPROVEMENTS IN MECHANICAL STOKERS OR APPARATUS FOR SUPPLYING FUEL TO FURNACES
Year: 1877

page_text: LETTERS PATENT to Henry Clifton Carver, of Llanidloes, in the County of
Montgomery, Engineer, for the Invention of "IMPROVEMENTS IN MECHANICAL
STOKERS OR APPARATUS FOR SUPPLYING FUEL TO FURNACES."
Sealed the 23rd March 1877, and dated the 16th January 1877.
PROVISIONAL SPECIFICATION left by the said Henry Clifton Carver at the
Office of the Commissioners of Patents on the 16th January 1877.
HENRY CLIFTON CARVER, of Llanidloes, in the County of Montgomery, Engineer.
"IMPROVEMENTS IN MECHANICAL STOKERS OR APPARATUS FOR SUPPLYING FUEL TO
FURNACES."
This Invention of improvements in mechanical stokers or apparatus for supplying
fuel to furnaces has reference mainly to (1) means whereby pieces of fuel exceeding
the size desired to be thrown on the fire are broken up or reduced, and whereby
the fuel is fed along a channel to a discharge outlet through which it passes (regu-
lated as herein-after mentioned) on to a distributing apparatus; (2) the use in
conjunction with the reducing and feeding apparatus of an appliance for regu-
lating, and when desired arresting the supply of fuel to the distributing apparatus,
while the reducing and feeding apparatus continues in operation, the arrangement
relatively to the reducing and feeding apparatus being such that any excess of
fuel carried along the channel is returned into the hopper; (3) the combination
with such regulating appliance, of an arrangement whereby when the furnace door
is opened the regulating apparatus is moved into such a position as that the supply
of fuel to the distributing apparatus is arrested, and so continues until the furnace
door is again closed; and (4) an arrangement for driving the distributing apparatus
in such manner as that its motion shall be arrested when and while the furnace door
is opened.
In a mechanical stoker or feeding apparatus embodying my improvements, the
fuel to be consumed having been placed in a suitable hopper or receptacle is acted
upon by travelling endless chains formed or provided with teeth or projections
either in conjunction with one or more fixed plates with or without teeth or pro-
jections, or without such fixed plate or plates according to the relative position of
the chains to one another (or one chain, as described, may be used in conjunction

page_text: with one or more fixed plates with or without teeth or projections). Thus pieces of
fuel exceeding the size desired to be thrown on to the fire are broken up or reduced
by the action of the teeth or projections; the fuel that is not too large including
that which has been broken up, as described, is fed onward to and along a channel
or passage having an outlet, the area of which is regulated by an adjustable slide or
door which may be adjusted to any required position and be operated from the
furnace door, so that when the furnace door is opened the adjustable regulating
slide or door will be forced into such a position that the fuel fed towards it by the
endless chain or chains will be returned to the hopper or receptacle through a
suitable aperture provided for the purpose, and this will continue until the furnace
door is again closed.
The means just described for arresting the supply of fuel to the distributing
apparatus are more especially intended to be used when the distributing apparatus
is placed upon the furnace door, in which case when the furnace door is opened it is
of course displaced from its proper position for scattering the fuel on the fire.
When the furnace door and adjustable regulating slide or door are not in the
positions just referred to, the fuel fed towards the regulating slide or door passes
through the outlet in quantities depending upon the area of the outlet, as regulated
by the said slide or door to the distributing apparatus.
The distributing apparatus intended to be used in conjunction with these im-
provements is of that class which consists of revolving fans or beaters which scatter
the fuel which is fed to them over the fire, and the improved means for driving such
fans or beaters when carried by the furnace door consist for the shaft of each of a
flexible spiral coil of wire, one end of which is connected to one end of the said
shaft, and the other end to one end of an intermediate shaft or spindle which is
rotated by some other shaft or spindle belonging to the apparatus through the
intervention of friction gearing, so that when the furnace door is opened the friction
wheels are moved out of contact and the distributing apparatus is arrested.
It will be evident that mechanical stokers or feeders embodying my improvements
or some of them may be constructed in various forms without departure from the
distinctive features of my Invention, as above set forth.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Henry Clifton Carver in the Great Seal Patent Office on the 16th
July 1877.
"
HENRY CLIFTON CARVER, of Llanidloes, in the County of Montgomery, Engineer.
'IMPROVEMENTS IN MECHANICAL STOKERS OR APPARATUS FOR SUPPLYING FUEL TO
FURNACES."
This Invention of improvements in mechanical stokers or apparatus for supplying
fuel to furnaces has reference mainly to (1) means whereby pieces of fuel exceeding
the size desired to be thrown on the fire are broken up or reduced, and whereby
the fuel is fed along a channel to a discharge outlet through which it passes (regu-
lated as herein-after mentioned) on to a distributing apparatus; (2) the use in con-
junction with the reducing and feeding apparatus, of an appliance for regulating,
and when desired arresting the supply of fuel to the distributing apparatus while
the reducing and feeding apparatus continues in operation, the arrangement relatively
to the reducing and feeding apparatus being such that any excess of fuel carried
along the channel is returned into the hopper; and (3) an arrangement for driving
the distributing apparatus in such manner as that its motion shall be arrested when
and while the furnace door is opened.
Fig. 1 shews in side elevation a mechanical stoker or feeding apparatus embodying
my improvements attached to a single flued boiler, which is shown in longitudinal
section; Fig. 2 is a front elevation partly in section; Fig. 3 is a plan.

page_text: 10 ATE VIC WO UL UHC CHRIS Cila, US ՍՍԱՆ WRLOGIS
rollers, and pressure plates.
Figs. 7 and 8 are views of the beaters and of the cylinder of the distributor which
carries the said beaters; this cylinder is supposed to be opened out so that its
surface lies on the plane of the paper.
Fig. 9 shows an alternative method of driving the distributing apparatus.
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a is the fuel hopper which fits into the breaking box b in which the fuel is
broken up. This box is secured in the present case to the boiler c, as shown. dis
the outlet leading into the delivery spout e through which the fuel is fed to the
distributing apparatus arranged in the fire door f; g is a plate placed opposite the
endless chain h in the breaking box, and is provided with projecting teeth g¹. The
endless chain h is of peculiar construction, and by it the fuel is broken and con-
veyed into and along the channel i which is formed between the chain and the
inclined under part of the breaking box. The fuel is thus either discharged into
the spout e or returned partly or wholly into the breaking box and hopper through
the aperture k. The bars or links h of the endless chain are strung together by the
pins l, and some of them are provided with teeth or projections h₁, as shewn. The
endless chain is supported by the shafts m, n, the shaft m being provided with
rollers o on which the pins are carried, and the shaft n with toothed wheels p
which gear into the pins l. On the shaft n is a worm wheel 9 which gears into a
worm secured upon a shaft s which is supported by a footstep t and guide or
hollow bracket t¹, and carries at its upper end the fast and loose pulleys u, u', and
at its lower end a short gudgeon or pin which passes through the footstep t, and to
which is connected the spiral coil v. The other end of this coil is connected to the
spindle w, on which is fastened the distributor x provided with the beaters ¹, the
arrangement of which is more particularly shewn in Figs. 7 and 8. y is the shaft
carried on the furnace front by the brackets z, z¹, and provided with the levers 1-2,
which are actuated respectively by the opening and closing of the fire door f. 3 is
another lever upon the same shaft as the levers 1 and 2, and is connected to the
belt fork rod 4 which is retained in the position requisite for keeping the belt
which drives the machine upon either the fast or loose pulleys, as required, by
means of the notches 5, bracket 6, and spring 7. 8 is a valve or plate which is
made to slide opposite the opening d by means of the two racks 9, one on either
side of the outside of the spout e. These racks move up and down in guides or
casings 16, and are provided with projections which pass through long slots in the
sides of the spout e, and take into the valve or plate 8. 17 and 18 are spur
wheels keyed upon a cross shaft and gear into the racks. 19 is a handle (the arm
of which is flexible) made fast upon the cross shaft just mentioned, and having a
tooth or projection which gears into teeth provided upon the face of a fixed sector 20
in such a manner that the flexible arm allows of the handle being pulled out of gear
with the sector for the purpose of adjusting the valve or plate 8. The box b is for
convenience made in two parts, the division being in the plane shewn by the centre
line 10-11.
An oil dish fast upon the shaft 8 is provided below the footstep t. 12 is a plate
supporting one end of each of the shafts m, n, and one side of the pressure plate 13,
the other side being supported in a groove on the other side of the box b. The
plate 13 is placed inside the fold of the endless chain, and prevents the chain from
yielding under the pressure caused in breaking and feeding the fuel. The plate 12
is made removeable in order to facilitate access to the chain and other parts. 14 is
a vibrating plate for directing tlie fuel on to the distributor in the manner which is
most suitable according to various changes of circumstances. 15 is the furnace
front on which the fire door is hinged.
The action of the machine is as follows:-Motion having been communicated to
the machine by means of a belt on the fast pulley u¹ fuel is placed in the hopper &
and breaking box b. The chain e moves in the direction shewn by the arrow in
Fig. 1, and carries down the fuel by means of the teeth into the channel i, at the
same time breaking those pieces which are too large to pass into the channel by

page_text: pressing them against the plate g and its teeth g¹. The fuel which is carried. along
the channel is either discharged through the outlet d or is returned partly or
wholly through the aperture k, according to the position of the valve or plate 8.
The fuel which is discharged into the spout e passes down through the top of the
fire door f on to the distributor x, the beaters ¹ of which scatter the fuel over the
fire-grate. When the fire-door f is opened it comes into contact with the lever 1,
and thus vibrates the shaft y and lever 3, which thrusts up the belt fork rod 4, and
thus forces the belt on to the loose pulley and stops the machine which would
otherwise discharge the fuel into the stoke hole. When the door is again closed it
comes into contact with the lever 2, causes the shaft y to return to its former
position, and the belt is returned on to the fast pulley; thus putting the machine
in motion again.
In order to regulate the quantity of fuel discharged on the fire-grate the valve or
plate 8 is moved up or down in the outlet. d (according as less or more fuel is
required) by means of the handle 19.
In Fig. 9 (which as already mentioned shews a modification of the foregoing
arrangement as regards the method of driving the distributor) 21 is a spur wheel
fast upon the shaft s; and 22 is another spur wheel fast upon a short spindle which
is carried in the socket t¹¹ which forms part of the footstep t, and to the lower end
of this short spindle is attached the spiral coil v which drives the distributor.
In the case of double flued boilers I either place an entirely independent machine
as for a single flued boiler opposite each flue, or I connect the two machines by a
single horizontal shaft driving both of the endless chains (thus using one worm and
worm wheel only), and for driving the distributors I connect one spiral coil to a
gudgeon in the end of the worm spindle, as already described, and another to an
intermediate spindle, as described in the foregoing alternative arrangements, and
these two coils are connected to the two distributors respectively, and the vibrating
shaft for operating the belt fork is actuated by each of the two furnace doors when
either is open by means of levers in a manner similar to that already described.
Having described the nature of my said Invention, and explained the manner of
carrying the same into practical effect, I would remark that I do not claim generally
as of my Invention the combination in a mechanical stoker of apparatus for breaking
the fuel with apparatus for distributing the same, and, save and except as herein-
after mentioned, I do not intend to claim any of the mechanical parts of the
apparatus herein-before shewn and described, when taken separately and apart.
from the combination or application thereof, in manner and for the purposes herein
described; but what I consider to be novel and original and therefore claim as
secured to me by the herein-before in part recited Letters Patent is,―
1st. The application and use of the toothed endless chain, as herein-before
described, for the purposes specified.
2ndly. The method of regulating the supply of fuel to the distributor by the use
of the adjustable valve or plate in conjunction with the return inlet through which
excess of fuel carried out of the hopper by the breaking or feeding apparatus is
returned to the hopper, in the manner herein-before described.
3rdly. The constructing mechanical stokers or apparatus for supplying fuel to
furnaces, as herein-before described and illustrated in the accompanying Drawings.
In witness whereof, I, the said Henry Clifton Carver, have hereunto set my
hand and seal, this Thirteenth day of July, in the year of our Lord One
thousand eight hundred and seventy-seven.