IMPROVEMENTS IN STEAM ENGINES AND IN THE BOILERS AND FURNACES TO BE USED THEREWITH
Year: 1870

page_text: PROVISIONAL: SPECIFICATION left by Edward. Wood.at. the Office of
the Commissioners of Patents,, with his Petition, on the 19th
January 1870.
I, EDWARD WOOD, of Bolton, in the County of Lancaster, Engineer,
do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN STEAM ENGINES AND IN THE BOILERS AND FURNACES TO BE USED THEREWITH,"
to be as follows:
4
My improvements in steam engines apply, firstly, to that class of
engine known to engineers as the "Corless engine," and relate to the
valve gear of such engines, and more especially to the method of
regulating the "cut off" by the action of the governor. I employ thrce
eccentrics, one for each steam valve, and the third for the exhaust..
Two of these eccentrics are connected by eccentric rods to two vertical.
working levers (one to each steam valve), the upper end of which carry
catches which act upon the sliding spindle, which is provided with a
"dash pot," and connected to the lever fixed on the spindle of the·
rolling steam valve. The end of the catch is furnished with a finger,
which can be raised or lowered by means of a small roller acted upon
by levers and links connected to the governor rod. As either eccentric

page_text: causes its vertical lever to vibrate the catch at the top pushes forward
the sliding spindle and opens the valve. As the lever continues to move
on the finger of the catch engages the small roller above named, and the
catch is lifted clear of the spindle; a spring then closes the valve.
The rise and fall of the governor rod affects the position of the said
roller, and so varies the cut off. To one of the levers connected to the
governor rod is attached a link connecting it with a lever, which when
the governor. rod falls to its lowest point (from any cause) lifts up the
catch out of gear and so stops the engine.
My improvements in steam engines apply, secondly, to that class of
steam engines known to engineers as compound cylinder engines, and
consists in placing the high-pressure and low-pressure steam cylinders
both in the same axial line, that is, end to end, the piston of the larger
or low-pressure cylinder being provided with two piston rods, which pass
one on each side of the higher pressure cylinder which is in the centre,
the three rods being parallel to each other.
A third improvement in steam engines relates to the gland through
which the valve spindle passes, and consists in the use or employment of
an outside bearing for the spindle beyond the lever, and in forming such
bearing in one piece with the body of the gland by means of an arch or
curved piece uniting the two and passing over the boss of the lever.
My fourth improvement in steam engines relates to what are known
to engineers as "ejector condensors," and consists principally in the
employment of a centrifugal or other pump for the purpose of raising
the feed water for such condensors to a higher level than that where the
water is discharged, so that the fall of the water in the discharge pipe.
acts as a siphon and assists the working of the condensor.
My improvement in steam boilers consists principally in a combination
of horizontal traverse tubes with vertical hanging tubes closed at the
bottom, and having circulation pipes inside, known to engineers as
"Field tubes." The boiler is made with a vertical water space or wall at
cach side supporting the ends of the transverse tubes, which are placed
near together and closed in at the top, sides, and ends with plates, tiles,
or fire-clay. The transverse tubes which are over the fire or furnace
have no "Field tubes" connected to them, but those in the flue behind
the bridge are supplied with a series of hanging or "Field tubes." A
horizontal feed pipe having branches to each transverse tube extends the
whole length of the boiler, and the side water spaces are also connected

page_text: with this feed pipe; a steam pipe also runs along the top, having a
short vertical connection with each transverse tube. The furnace may
be either of the ordinary fixed kind, or of the kind herein-after described,
and the front part of the boiler may be made similar to an ordinary.
Cornish boiler, with two flues to carry the furnace, and the back part of
the construction above described.
My improvements in furnaces relate to that class of furnace known as
the "endless travelling bar" furnace, and are designed principally with
a view to render such furnaces applicable more readily and efficiently to
Cornish steam boilers.
"
The Invention consists chiefly in the use or employment of endless
travelling chains of links merely (instead of the endless travelling fire-
bars heretofore employed), the said chains being placed between and in
connection with fixed longitudinal fire-bars, and being supported and
running (wholly or partially) on intermediate longitudinal bars placed
rather lower than the others, or on rollers or discs, so as to bring the
surface of the chains to about the same level as or only slightly above
the level of the said first-named bars. The form of the chain which I
prefer to use for ordinary purposes is that known as the "flat curb "
chain, but other forms of chain might be used with advantage. The use
of chains of links merely to carry on the fuel whilst the weight is
supported on the fixed bars (instead of chains of travelling fire-bars, as
heretofore employed) admits of the use of a much smaller roller inside
the flue for the chains to pass round, and hence it occupies much less
space in the said flue. In some cases by making the links of the chains
sufficiently strong and placing the chains close together side by side the
fixed bars may be dispensed with, in which case the chains will have to
support the weight of the fuel, as well as to carry it forwards, and if
found necessary they may be supported at intervals by bars, rollers, or
discs. I propose also to make the back roller (or that near the bridge)
into the driving roller for the endless chains, giving motion to it by
gearing, or by means of an endless chain, and to make the said roller
either in short pieces or dises with air spaces between, or in one hollow
roller perforated with air holes. Instead of a roller in front for the
chains to pass over I mount a series of discs loosely and independently
of each other on a fixed central spindle, so that each chain has its own
separate pulley or disc. The hollow water stop or bridge is or may be a
fixture, and the supply and return pipes pass along the side of the fluc

page_text: to the front, where they are connected to the water space of the boiler,
the joint between the said pipes and the sides of the flue to which they
are fixed being made air-tight with fire-clay, the whole being so
arranged that the moving carriage or frame with the rollers and chains
and their appliances can be run in or out without disturbing the pipes or
interfering with the fire-clay packing, and when in its working position
will be sufficiently close to the said pipes to need no brick or fire-clay
joint. Instead of the pipe on one side of the flue taking water to the
water bridge and the pipe on the other side being the return pipe, both
pipes may feed the bridge, the water from which may pass by means of
another pipe through the top of the flue, or otherwise into the boiler; or
the arrangement may be reversed, in which case the pipe from the
bridge would enter the bottom or side of the flue; or the circulating
pipes may be placed behind the bridge.