Improvements in Steam Engines and in Means for Driving High Speed Shafts therefrom.
Year: 1895

page_text: Date of Application, 23rd Feb., 1895-Accepted, 13th Apr., 1895
COMPLETE SPECIFICATION.
Improvements in Steam Engines and in Means for Driving High
Speed Shafts therefrom.
I, SAMUEL CLELAND DAVIDSON of Sirocco Engineering Works, Belfast,
Ireland, Merchant, 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 :—
This invention has reference to steara engines and to means for driving therefrom
high speed shafts such as those for rotary fans or dynamos and it relates more
particularly to the construction of the piston rod or cross head guide, and the
general arrangement therewith of the other parts of the engine and of the bed
plate or standard in a single or double cylinder engine; and also to the combination
of the so constructed engine with a shaft or spindle, such as that of a fan or a
dynamo, mounted on the said bed plate or standard, so as to be driven at a high
speed, while the engine itself runs at a relatively slow speed, whereby the wear of
the moving parts of the engine is reduced to a minimum, and its durability
equivalently ensured.
According to this invention the piston rod guide is so constructed that while it
can be easily moulded and cast in one piece, bored and fitted as an end cover and
supporting bracket for the engine cylinder, and bolted or otherwise secured as a
strongly rigid side bracket attachment to the bed plate or to the standard or
supporting frame of a fan, dynamo, winch or other apparatus, it has in addition to
the opening usually made in cylindrical guides, for getting at the cross head or
slide block of the piston rod, and while amply retaining its strength as a connecting
bracket between the cylinder and the bed plate or standard, two special openings
provided in it, one on its upper and the other on its under side through which the
bolts in the piston rod gland can be conveniently screwed up and tightened as
required, even when the engine is running. As regards the employment of engines
thus constructed for driving a high-speed shaft, such as that for a fan or a dynamo
the bed plate of the engine is according to this invention so designed that it also
acts as a standard for carrying the bearings of the said high speed shaft above the
main body of the engine, and parallel to the crank shaft, which is fitted with a
driving pulley of sufficiently larger relative diameter to a corresponding driven
pulley on the high speed shaft, so that a belt or band from the one pulley to the
other will drive the shaft at any required high speed, while the moving parts of
the engine itself are running at a relatively slow speed, thereby minimising their
wear and ensuring a satisfactory durability of the engine as a whole, while at same
time the high speed rotation of the fan or dynamo shaft is accomplished with great
smoothness, and freedom from the rapid vibratory motion to which such high speed
shafts are ordinarily subject, when driven by the direct attachment to a crank
thereon of either a single, or double cylinder high speed engine.
The accompanying drawings more fully illustrate the
invention:-
nature of this
Figure 1 is a side elevation; Figure 2 a plan and Figure 3 an end elevation of
a single cylinder engine constructed according to this invention with the piston
guide mounted as a side bracket attachment to the bed plate, and forming a
connecting bracket between the bed plate and the cylinder.
Figure 4 is a side elevation; Figure 5 a plan and Figure 6 an end elevation of a
double cylinder engine, in which the piston guide is mounted and applied in the
same way as in Figures 1, 2 and 3,

page_text: Figure 7 is a side elevation; Figure 8 an end elevation and Figure 9 a plan of
the improved single cylinder engine shown in Figures 1, 2 and 3 with the bed
plate designed to carry the bearings of a fan shaft with fan mounted thereon, the
fan shaft being driven from a pulley on the crank shaft of the engine, which is also
mounted on the bed plate;
Figure 10 is a side elevation; Figure 11 an end elevation and Figure 12 a plan
of the improved double cylinder engine shown in Figures 4, 5 and 6 with the bed
plate designed to carry a dynamo and the bearings of the dynamo shaft which
shaft is driven from a pulley on the crank shaft of the engine which is also
mounted on the bed plate.
The same letters of reference indicate the same parts in all the figures.
A is the bed plate of the engine; B B are the engine cylinders; CC the piston
rods; DD the cross heads; E E are cross head or piston rod guides and side
brackets bolted to bed plate A and carrying the cylinders B; E' E' are the special
openings herein before described in the guides E for access to the bolts of the piston
rod glands; E2 E2 are the ordinary openings in the guides E for access to the
cross heads; F F are the piston rod glands; G G the connecting rod; HH the
crank discs; II the excentrics; K is the crank shaft; L L the crank shaft
bearings; M the governor; N the driving pulley; O Figures 7, 8 and 9 is the
fan; P is the fan shaft or spindle; Q is the pulley on the fan shaft P driven from
the pulley N on the crank shaft K of the engine; R R are the bearings of fan
shaft P, bolted and carried on the bed plate A of the engine; S Figures 10, 11
and 12 is the dynamo carried on the bed plate A of the engine; T is the dynamo
shaft U is the pulley on the shaft T driven from the pulley N'on the crank
shaft K of the engine; V V are the bearings of dynamo shaft.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. In a steam engine, the constructive design and arrangement whereby the
piston rod or cross head guide acts as a strongly rigid side bracket attachment to
the bed plate or standard of the engine, and as an end cover to and supporting
bracket for the cylinder, and has, in addition to the opening usually formed in
cylindrical guides, for getting at the piston cross head or slide block, and while
amply retaining its strength as a connecting bracket between the cylinder and the
bed plate or standard, two special openings provided in it, one on its upper and
the other on its under side, for enabling the bolts of the piston rod glands to be
conveniently screwed up or tightened as required, even when the engine is running,
all substantially as and for the purposes hereinbefore described and represented in
the accompanying drawings.
2. The combination with an engine having the constructive design and
arrangement referred to in Claim 1, of a high speed shaft or spindle, such as that
for a fan or a dynamo, mounted in bearings on an elevated portion of the bed plate
of the engine, or upon a standard thereon, and parallel to the crank shaft of the
engine, the said crank shaft being fitted with a driving pulley of sufficiently larger
relative diameter to a corresponding driven pulley on the high speed shaft or
spindle, so that by means of a belt or band from the one pulley to the other, any
required speed of drive may be communicated to the high speed shaft, while the
engine itself runs at a comparatively slow speed, all substantially as hereinbefore
described and represented in the accompanying drawings.
Dated this 23rd day of February 1895.
J. C. MEWBURN & ELLIS,
55 and 56, Chancery Lane, London, Chartered Patent Agents,