IMPROVEMENTS IN LOCOMOTIVE STEAM ENGINES
Year: 1884

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COMPLETE SPECIFICATION.
23.
I, EDMUND HUNT, of 87 St. Vincent Street, Glasgow, in the County of Lanark,
North Britain, Patent Agent, do heroby declare the nature of the said invention.
for IMPROVEMENTS IN LOCOMOTIVE STEAM ENGINES (A communication from
Walter John Hammond, Engineer of the Companhia Paulista, Jundiahy, San
Paulo, Brazil) and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement that is to say :-
The said Invention has for its object to combine certain parts of locomotive
steam engines in an improved manner and so that whilst what are known as
inside cylinders are used these can be made of a comparatively large size, and a
very powerful locomotive can be constructed suitable for heavy loads and for steep
gradients.
In carrying out the Invention the two cylinders aro placed close together, and
instead of the valve casings occupying space between the cylinders as in ordinary
arrangements with inside cylinders, these casings are placed on the outer sides of
the cylinders. The longitudinal vertical side plates of the frame of the locomotive
are made of extra depth at the forward end where the cylinders are placed; and
the valve casings project through openings made in these plates the valve rods
being outside of the plates. The valve motions are of a kind deriving their
movements from the combined swinging and longitudinal movements of the
connecting rods, but are modified from. ordinary arrangements of such valve
motions to adapt them to the improved ärrangement of cylinders and framing
used in carrying out the present Invention.
And in order that the said Invention and the manner of performing the same
may be properly understood there is hereunto appended a sheet of explanatory
drawings to bo hereinafter referred to and representing a part of a locomotive
steam engine as constructed with the improvements. Figure, 1, is a side elevation,
figure, 2, is a longitudinal vertical section; and figure, 3, is a sectional plan. In
these drawings the same reference numerals are used to mark the same or like
parts wherever they are repeated.
The locomotive of which part is shown in the drawings is one having eight
coupled wheels and is designed foọr drawing heavy loads on steep gradients. The

page_text: two cylinders, 4, placed between the deep side frame plates, 5, have their piston
rods, 6, connected by rods, 7, to cranks, 8, on the axle, 9, of the third pair of
coupled wheels, the cylinders and other parts being sufficiently raised to work
over the axles, 10, 11, of the first and second pairs of coupled wheels, whilst the
piston-rod slide blocks work between guide bars, 12, which are fixed to a
transverse frame piece, 13.
Each cylinder, 4, is made with its valve casing, 14, on its outer side, and the
valve casing projects through an opening made for it in the side frame plate, 5,
which arrangement whilst it allows of larger cylinders being got in within a frame
of given width, has also the advantage that the valves are very conveniently
accessible. The valve-casing cover, 15, is on the outside, and the valve rod, 16,
working through the usual stuffing box, 17, is also on the outside. The valve
motion for each cylinder comprises a forked lever, 18, jointed by a pin, 19, to the
connecting rod, 7, and having its other end jointed to a radius rod, 20, which. is
jointed to the transverse frame piece, 13. The lever, 18, is connected by a pair
of links, 21, to a pair of blocks, 22, fitted to slide in arc-shaped guide grooves in
a pair of blocks, 23, fixed in a rocking frame, 24, which carries similar blocks for
the valve motions of both cylinders. This rocking frame, 24, extends transversely
between the-side frame plates, 5) and is carried in bearings, 25, fixed to those
plates whilst on one end of it there is fixed a lover, 26, connected by a rod, 27,
to the valve-motion or reversing hand lever at the footplate. At a point to the
inner side of the blocks, 22, (instead of the outer side as in ordinary arrangements
of the valve motion) the links, 21, have jointed to them a rod, 28, the other end
of which is jointed to a lover, 29, on a transverse rocking shaft, 30. There are
separate rocking shafts, 30, for the two cylinders and each extends from the middle
to a point outside of the side frame plates, 5; and has a lever, 31, fixed on its outer
end and connected by a rod, 32, to the respectivo valve rod, 16. The two rocking
shafts, 30, are carried in bearings, 33, 34, the outer ones fixed on the side frame
plates, 5, and the inner ones fixed on the transverse frame piece, 13.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed, I declare that what
I claim is
The combination in a locomotive steam engine, of inside cylinders having their
valve casings projecting through the side frame plates, with valve motions of the
kind deriving their movements from the swinging and longitudinal movements
of the connecting rods, and with rocking shafts for transferring the valve-motion
movements to the outside of the frame, substantially as hereinbefore described.
Dated this eighth day of November 1884.