Improvements in Furnaces for Heating and Melting Metals.
Year: 1892

page_text: Date of Application, 12th Apr., 1892
Complete Specification Left, 11th Feb., 1893-Accepted, 18th Mar., 1893
PROVISIONAL SPECIFICATION.
Improvements in Furnaces for Heating and Melting Metals.
We, AMBROSE EDMUND BUTLER, BERNARD FAWCETT BUTLER and HUGH
MYDDLETON BUTLER of Kirkstall Forge, near Leeds, County of York, Iron
Masters, trading as the Kirkstall Forge Co., do hereby declare the nature of this
invention to be as follows:-
The objects of this invention are to effect economy in the working of heating
and melting furnaces such as are used for heating and melting iron and steel; to
enable comparatively small furnaces to be employed in some cases where heretofore
large furnaces have been needful; and to enable heating and melting furnaces to
be quickly heated to the extent requisite for commencing work, thereby dispensing
with the necessity of firing up many hours beforehand as heretofore.
In a construction of furnace according to this invention a close combustion
chamber without bars is provided with stoking mechanism for automatically
feeding fuel from a suitable hopper or hoppers to the combustion chamber in small
quantities at a time and regularly during working operations, so that all parts of
the upper surface of the burning fuel in the combustion chamber will be fed with
fresh fuel and such surface maintained practically level, the fuel being distributed
over the entire surface of the incandescent fuel in the combustion chamber in a
practically uniform and regular manner and without having to open and shut a
door as is usually the case. Provision is made to obviate excessive heating of the
stoking mechanism from the wall of the furnace. The fuel may be supplied to the
Also in connection
hopper or hoppers by an automatic conveyor or conveyors.
with the combustion chamber there is a blast supply. In one arrangement the blast
supply pipe is connected with the combustion chamber by a number of nozzles each
succeeding one being of somewhat smaller diameter than the one next before it, in
order to equalize as far as practicable the blast supply to the different parts of the
combustion chamber. The blast may be heated by radiation from the furnace
bottom and sides and the escaping gases in the flue.
The combustion chamber is constructed in such a manner that it can be readily
cleaned out; one construction for this purpose is with openings at opposite ends or
sides of the chamber, provided with means such as water cased doors (and door
frames) for closing such openings. According to another arrangement the com-
bustion chamber is constructed with a false bottom. Another plan is to construct
the combustion chamber with a removable side or to make the chamber itself
removable from the rest of the furnace.
As will be evident heating and melting furnaces with automatic fuel feeding
apparatus according to this invention may be constructed in various forms according
to requirement.
Dated this 12th day of April 1892.
W. LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicants.

page_text: COMPLETE SPECIFICATION.
Improvements in Furnaces for Heating and Melting Metals.
We, AMBROSE EDMUND BUTLER, BERNARD FAWCETT BUTLER and HUGH
MYDDLETON BUTLER, of Kirkstall Forge, near Leeds, in the County of York,
Iron Masters, trading as the Kirkstall Forge Co., do hereby declare the nature of
this invention and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement :-
The objects of this invention are to effect economy in the working of heating
and melting furnaces such as are used for heating and melting iron and steel; to
enable comparatively small furnaces to be employed in some cases where heretofore
large furnaces have been needful, and to enable heating and melting furnaces to be
quickly heated to the extent requisite for commencing work, thereby dispensing
with the necessity of firing up many hours beforehand as heretofore.
In a construction of furnace according to this invention a close combustion
chamber without bars is provided with stoking mechanism for automatically
feeding fuel from a suitable hopper or hoppers to the combustion chamber in small
quantities at a time and regularly during working operations, so that all parts of
the upper surface of the burning fuel in the combustion chamber will be fed with
fresh fuel and such surface maintained practically level, the fuel being distributed
over the entire surface of the incandescent fuel in the combustion chamber in a
practically uniform and regular manner and without having to open and shut a
door as is usually the case. Provision is made to obviate excessive heating of the
stoking mechanism from the wall of the furnace. The fuel may be supplied to the
hopper or hoppers by an automatic conveyor or conveyors. Also in connection
with the combustion chamber there is a blast supply. The blast supply pipe is or
may be connected with the combustion chamber by a number of nozzles each
succeeding one being of somewhat smaller diameter than the one next before it, in
order to equalize as far as practicable the blast supply to the different parts of the
combustion chamber. The blast may be heated by radiation from the furnace
bottom and sides and the escaping gases in the flue.
As will be evident heating and melting furnaces with automatic fuel feeding
apparatus according to this invention may be constructed in various forms according
to requirement.
In the accompanying drawings :-
Figs. 1 and 2 are respectively a plan and a side elevation of a metal heating
furnace constructed according to this invention.
Fig. 3 is a cross section thereof to a larger scale, the section being taken
through the combustion chamber, and the stoking mechanism being shown in end
elevation.
Figs. 4, 5 and 6 are respectively a front elevation and right and left hand end
elevations, to a still larger scale, of stoking mechanism suitable for feeding fuel
from a hopper to the closed combustion chamber of the furnace.
Fig. 7 is a sectional plan to a smaller scale of part of such mechanism taken on
the line Y. Z. of Fig. 5.
Fig. 8 is a plan of the shovel forming part of such mechanism.
1 is a heating furnace constructed according to this invention with a closed
combustion chamber 2 that is without fire bars, and extends transversely across the
furnace. 3 is a feeding aperture through which fuel is fed from a hopper 4 by
stoking mechanism 5 the construction of which is such as to automatically deliver
the fuel in small quantities at a time and regularly during working operations, BO
that all parts of the upper surface of the burning fuel will be fed with fresh fuel
and thereby be maintained practically level. A suitable construction of stoking
mechanism for the purpose mentioned and which we have found to give satisfactory
results in practice is that known as Bennis' stoker. The construction of this

page_text: stoker is well known but may be briefly described as follows, reference being had
to Figs 4 to 8 inclusive of the accompanying drawings:
:-
6 is a fuel hopper at the bottom of which is a plate or pusher 7 to which a
reciprocating motion is imparted by one arm 8 of a lever pivoted at 9 and the
other arm 8 of which is actuated by an adjustable double sided cam 10 that is
fixed on the main driving shaft 11, the arrangement being such that coal falling in
front of the pusher is caused thereby to fall in front of a shovel 12 by which it is
thrown through the passage 3 into the combustion chamber of the furnace. The
shovel 12 which is preferably made of sheet steel and with angular faces 12 as
shown in Fig. 8, is attached to one arm 13 of a lever mounted on a pin 14 and the
other arm 15 of which is connected to the adjacent ends of springs 16 the other
ends of which are adjustably fixed by nuts 17 to a flange 18 formed on the side of
the hopper 6. On the main driving shaft 11, which is driven in any convenient
manner, is fixed a boss 19 formed with four cams or tappets, 19* 19° 19° and 19ª
that are of different lengths and are adapted, when the shaft 11 is rotated, to act
alternately against a lateral extension 13 of the lever arm 13, the arrangement
being such that each cam or tappet acts to move hack the shovel 12 and arm 13
against the action of the springs 16, and when the lever arm 13 is released by each
cam or tappet in turn leaving the lateral extension 13ª, the springs act to impart a
sudden forward movement to the lever arm whereby the shovel is caused to throw
or eject the fuel in front of it through the passage 3, the distances to which the
fuel is thus thrown varying with the extent to which the springs are extended by
the action of the cams or tappets which for this purpose are made of different
lengths as well understood. By this means the fuel is thrown to different distances
for each of the four strokes corresponding to the four cams or tappets, and owing
to the angular form of the shovel, the fuel is thrown sideways as well as forwards,
and thereby equally distributed over the surface of the incandescent fuel in the
closed combustion chamber 2. By adjusting the two parts of the cam 10 to or
from each other, the stroke of the pusher 7 and the quantity of coal fed forward
thereby at each stroke, can be regulated to suit requirement as well understood.
20 is a plate hinged to the back of the hopper 6 and to which an oscillating
motion is imparted by means of cams 21 fixed on a shaft 22 that is driven from the
shaft 11 by an endless chain 23, the motion of the plate serving to facilitate the
uniform feeding of the fuel to the pusher and obviating clogging. 24 is a plate
hinged to the sides of the hopper at the points 25. This plate is formed with side
flanges 24 between which the fuel fed forward by the pusher 7, is received and
which serve to ensure that this fuel shall drop immediately in front of the shovel 12
ready for injection into the combustion chamber. The said plate also prevents
back draught.
The stoking apparatus is supported at a short distance from the side of the
furnace and opposite the feeding passage 3, by a tubular extension 26 (Fig. 3).
This extension is formed with a passage at 26 that is normally closed by a
cover 26 and through which a rod can be pressed when necessary, to clear the
passage 3 of any fuel that may collect therein, and for stirring up the fuel in the
combustion chamber when required.
27 is a blast supply pipe connected with the lower end of the combustion
chamber by a number of nozzles 28 each succeeding one of which is of somewhat
smaller diameter than the one next before it, in order to equalize, as far as
practicable, the blast supply to the different parts of the combustion chamber and
in this way effect a practicably uniform combustion of the fuel throughout the
width of the combustion chamber.
30 is the
The blast may be heated in any convenient or suitable manner. In the
construction now being described the blast is for this purpose led through a
serpentine pipe 29 embedded in the hearth 1ª of the furnace as shown.
chimney through which the hot gas and products of combustion escape.
Fig. 9 is a plan, partly in horizontal section;

page_text: Fig. 10 is a side elevation, partly in vertical section, and
Fig. 11 is an end view, to a larger scale, showing the application of this invention
to a heating furnace 1 the hot gases and products of combustion from which are led
another way to the chimney 30 through Hues 31 for the purpose of heating a steam
generator 32 in a manner well understood. In this example the air blast is passed
through coiled pipes 29 arranged vertically within a chamber 31" between the
flues 31 and the base of the chimney.0. These coiled pipes which may be provided
with vertically movable scrapers 33 acting in a known manner to keep the
exteriors of the pipes free from soot, are connected with the blast pipes 27 by a
pipe 27 that is led through one of the flues 31 and through one of the side walls of
the furnace 1.
The closed combustion chamber 2 in each case is formed between the end wall
and the bridge wall 2° of the furnace and is constructed in such a manner that it
can be readily cleaned out when necessary. In the construction shown in Figs. 1, 2
and 3, and in Figs. 9, 10 and 11, the ends of the combustion chamber are closed by
thin brick walls 34 that can be readily removed for withdrawing ashes through the
chamber through the openings 2* and afterward be re-built to again close the
combustion chamber.
In the construction shown in Figs. 12, 13 and 14, which are respectively a
transverse section, a side elevation and a horizontal section of the combustion
chamber and of the furnace the clearing holes 2* of the combustion chamber are
closed by hinged water cased doors 35, fitted in water cased door frames 36, suitably
arranged pipes 37, being provided for causing water to flow through both the doors
and frames for the purpose of keeping them cool.
In the construction shown in Figs. 15, 16 and 17, which are respectively trans-
verse, longitudinal and horizontal sections of the combustion chamber end of the
furnace, the combustion chamber 2 is provided with a false or movable bottom
consisting of a horizontal plate 38 mounted to move in suitable guides 39 upon
anti-friction wheels or rollers 40 so as normally to close the bottom of the combustion
chamber 2 and separated from an ash pit 41 into which ashes can fall by gravity
when the plate 38 is sufficiently withdrawn. In the construction shown in Figs. 18,
19 and 20 which are respectively a side elevation, a horizontal section and an end
elevation of the combustion chamber end of the furnace, the end wall 2ª of the
combustion chamber with the metal casing 2° containing the same are hinged
as shown at 42 to a fixed plate 43 so that it can be turned into the open position
shown in side elevation in Fig. 21 when it is desired to clear out the combustion
chamber 2.
In the construction shown in Figs. 22, 23 and 24, which are respectively an end
elevation a side elevation and a horizontal section, the end wall 2" and the sides aud
bottom of the combustion chamber are made separate from the rest of the furnace
and as one structure that is provided with flanged wheels 44 arranged to run on
inclined rails 45 and is connected by a chain 46 with a winch barrel 47, the
arrangement being such that the end, sides and bottom of the combustion chamber
can be readily withdrawn by means of the winch from the rest of the furnace for
clearing purposes and can be afterwards returned, it may be by gravity, into the
closed position for re-use. In the examples shown in Figs. 12 to 24 inclusive, the
stoking mechanism, is for the sake of simplicity, omitted from the drawings.
Where a number of heating and melting furnaces with closed combustion
chambers and stoking mechanism according to this invention are arranged in line
or in other suitable manner fuel may be automatically fed to each of the fuel
hoppers 4 from a longitudinal trough 48, which is provided with screw conveyor,
and is fed from a hopper 49 into which fuel is delivered by a bucket conveyor 50
from a hopper 51 in a manner well understood.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed we declare that we do not
claim broadly a furnace for heating and melting metal constructed with a closed

page_text: chamber into which fuel is automatically fed by a fuel feeding apparatus but that
what we claim is :-
1. A furnace for heating or melting metals constructed with a closed combustion
chamber 2 (without bars) formed between the end and bridge walls of the furnace
and in communication at the lower part with a blast supply by a number of air
distributing nozzles or apertures, and provided with stoking mechanism adapted
to automatically throw or feed fuel from a suitable hopper into the combustion
chamber in small quantities at a time and regularly during working operations
so that all parts of the upper surface of the burning fuel in the combustion
chamber will be fed with fresh fuel substantially as described and shown for the
purposes specified.
2. Metal heating or melting furnaces of the kind referred to in the preceding
claim having the combustion chambers constructed and closed substantially as
herein before described with reference respectively to and shown in Figs. 1, 2
and 3; in Figs. 12, 13 and 14; in Figs. 15, 16 and 17; in Figs. 18 to 21
inclusive; and in Figs. 22, 23 and 24 of the accompanying drawings for the
specified.
Dated La
1
purpose
TOU
A. EDMUND BUTLER.
B. FAWCETT BUTLER.
H. M. BUTLER.
W. Lloyd Wise,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicants.