In- PROVEMENTS IN STEAM ENGINES, STEAM BOILER AND OTHER FURNACES, AND IN APPARATUS FOR HEATING FEED WATER
Year: 1868

page_text: PROVISIONAL SPECIFICATION left by William M'Naught at the
Office of the Commissioners of Patents, with his Petition, on the
10th September 1868.
I, WILLIAM M NAUGHT, of Rochdale, in the County of Lancaster,
Engineer, do hereby declare the nature of the said Invention for "In-
PROVEMENTS IN STEAM ENGINES, STEAM BOILER AND OTHER FURNACES, AND IN
APPARATUS FOR HEATING FEED WATER," to be as follows:-
Firstly. My Invention consists in an improved combination and
arrangement of fire-bars and mechanism for feeding fuel thereon, the
object of which is to economise fuel and consume the smoke. The bars
are placed lengthways of the furnace, and their inner ends are made to
slide or move on a cranked or rocking shaft, and their outer ends are
arranged to move upon a cranked shaft, which leaves the ash-pit clear.
Motion is given to the rocking or cranked shaft so as to slide or move
all the bars slowly forward towards the fire-bridge, carrying the fuel
along with them, and then a back movement is suddenly given to the
crank shaft to draw.all the bars back, leaving the fuel. The slow

page_text: .
forward movement imparted to the bars may be given by a cam, and
the back movement by a weight or weighted lever, or a spring, or the
mechanism may be actuated by a steam piston. Combined with the
arrangement of fire-bars above described is a hopper placed above the
outer ends of the fire-bars, and in the lower part of the "hopper" two
rollers are arranged, having spiked teeth for crushing the fuel and
feeding it on to the bars below.. These rollers are geered together and
may be actuated intermittently by a pawl and ratchet wheel. The
fire-bars may also be connected to each other laterally, so that a slight
rocking motion may be imparted to them to discharge the ashes. With
the above arrangement and combination of mechanism the " green
coal or fuel fed in front is slowly carried along, and that nearest the
bridge having become incandescent will consume the smoke and gases
passing over from the green fuel in front.
"
Secondly. My improvements relate to a hollow fire-bridge, and they
consist in making the bridge of such form that the gases will have to
pass under or through it; it is of iron or fire-clay in one or more
pieces, and has perforated holes or slits for the air to escape from it
downwards, and thus ashes cannot stop up the perforations, and by this
form and arrangement of bridge the bottoms or flues of boilers are
protected from cooling effect of the air passing from the bridge.
The admission of air to the bridge is regulated by a valve or door
actuated by hand or well-known self-acting mechanism or by connection
with the engine.
Thirdly. My improvements relate to apparatus for heating feed water
by pipes arranged in the flues from the furnace, and consist in giving
the up-and-down-motion to the scrapers acting to remove the soot from
the heating pipes by means of a "mangle-toothed wheel" and pinion,
instead of the mechanism hitherto used. The movement from the
mangle wheel is conveyed to the scrapers by bevel wheels and the usual
chain pulleys and chains. This part of my improvements also consists
in forming the scrapers of flat plates, their lower ends resting upon an
arm carried by the chains, the upper ends having pieces cut out to fit
the pipes when resting against them at an acute angle thereto. By this
arrangement the soot slides down the scrapers and is prevented from
accumulating upon them.
.

page_text: strains acting upon engines working the steam expansively, by which
means the expansive working of the steam may be carried to a greater
extent with increased economy, as engines having my improvements
applied will bear with safety a much greater pressure of steam at the
beginning of each stroke than engines as hitherto constructed. My
improvements consist in applying to steam engines a compensating
wheel or weights on arms made to oscillate by the engine, and arranged so
that the excess of the pressure of the steam at the beginning of the stroke
will be absorbed in overcoming the inertia of the mass of the compen-
sating wheel or weights which will give back the momentum thus
obtained during the second half of the stroke. Therefore the strains
upon the parts of the engine will be equalised, and the driving force
acting upon the crank and the consequent velocity will be nearly
uniform. The compensating wheel or arms with weights upon them
is mounted upon a shaft, so that the wheel or arms can oscillate, and
an arm upon this shaft is connected by a link or links with the piston
rod of the engine or the piston end of the beam in beam engines. The
shaft upon which the said compensating wheel is mounted may also be
used to work the air
pump or other pumps.
Fifthly. My improvements relate to the valve of steam engines, and
to means for cutting off the steam to the cylinders for expansive working.
by self-acting mechanism. The slide valve is made as long as it can
be worked in a valve chest nearly the length of the cylinder, so as to
shorten the ports as much as possible, and is made hollow, and the
exhaust steam passes into the said valve and out at a long slot into a,
similar slot on the interior face of the valve chest, which slot leads to
the exhaust branch. The steam is admitted to the cylinder through
ports at the end of such valve in the usual manner. Two superimposed
slides are worked upon the valves, which are similar to such as are in
general use, but are capable of being shifted further from or nearer to
each other, so as to vary the point at which the steam is cut off; this
is effected by connecting the said slides to the eccentric or cam which
works them by means of two spindles, one of which is hollow to allow
the other to pass through it; these spindles are attached to the slides,
and at the other end of each is a right-hand thread upon one and a left-
hand thread upon the other. Screwed upon the end of each spindle is
a long bush with opposite threads, and by turning the said bush round

page_text: in one direction or the other the ends of the said spindles will approach
or recede from each other and with them the slides. The outer spindle
passes through the stuffing box of the valve chest. The bush is made
steam-tight upon it by means of an elastic nut of india-rubber or other
suitable composition, provision being made for closing the same by
means of a stuffing box on the top of the bush when necessary and
upon the inner spindle; the said long bush is journalled in a cross bar
properly guided by slides; this cross bar is connected to the eccentric
rod and reciprocates with its motion. Upon the said bush is either a
worm wheel or a bevel wheel suitably geered to a shaft journalled to
the said cross bar, one of which wheels has a square hole or sliding key
to allow it to slide backwards and forwards on a shaft which is con-
nected by reversing wheels to the governor in the usual manner, so
that as this shaft turns in one direction or the other by the action of the
governor the said bush does the same and the slides consequently
approach or recede from each other as required.
Sixthly. My improvements relate to pistons and air pump buckets,
and are made upon those described in Specifications of one Patent
granted to myself, number 753, A.D. 1867, and of another Patent
granted to myself and another person, number 98, A.D. 1859, as
described in the Specifications of those Patents, the flexibility of the
rings for pistons and buckets is produced by certain portions being cut
out of the interior flange of the ring with intervening portions rigid.
My present improvements consist in making the interior of the said
flange to a certain curvature without any rigid portions, and in the
application of spiral or turned springs to the same.
Another improvement applicable to the pistons above referred unto
consists in a provision for restoring the true position of the axis of the
piston rod when worn downwards, which happens in horizontal and
inclined cylinders, by means of packings inserted on the under side
betwixt the piston body and the rings which raise the body into its true
position; this may also be effected by means of screws.
Sevently. My improvements relate to means for lubricating pistons,
valves, and other parts, and consists in driving the melted tallow or
lubricating matter from its closed receptacle to the parts to be lubricated
by forcing in water at the lower part of the receptacle by a pump worked
by the engine or occasionally by hand, and consequently forcing out

page_text: the lubricating matter through an orifice at the upper part of the
receptacle, the water thus injected being drawn off, when the tallow
is all driven out of the receptacle, and by this means the difficulties
which are met with when pumping tallow or other lubricating matter
are overcome.