Improvements in Steam Engines.
Year: 1886

page_text: Date of Application, 11th June, 1886.
Complete Left, 8th Mar., 1887.
Complete Accepted, 7th Apr., 1887.
Improvements in Steam Engines.
We, ROBERT RICHARDSON, Draughtsman, and STEPHEN ALLEY, of the firm of
Alley and McLellan, Engineer, both of Sentinel Works, Polmadie, in the County of
Renfrew, North Britain, do hereby declare the nature of this Invention to be as
follows, that is to say :--
Our said Invention has for its object to simplify and improve the construction of
steam engines having cylinders and reciprocating pistons.
In carrying out our Invention we employ a modification of an ordinary slide valve
for distributing steam to the ends of each cylinder, and in order to dispense with
complicated and troublesome valve gear we obtain a reversal of the motion of the
engine by means of a separate slide valve or a four-way cock controlling the steam
inlet passage, a passage leading to a condenser or the atmosphere and two passages
communicating with the cylinder valve casing. These last named passages have ports
in the sides of the valve casing there being a port face with the two cylinder ports
but without the usual middle port at the bottom of the casing. The slide valve is a
block formed with two internal cavities which have ports at its opposite sides, one for
each of the ports in the sides of the casing; and the valve is made with three ports
on its under side, the middle one communicating with one cavity and the other two
ports with the other cavity. The valve is made not to fit tightly between the two
sides of the valve casing but so as to be capable of a slight transverse movement;
and the valve rod is connected to it in a manner to allow of such transverse movement.
The steam enters the valve casing at one side and exhausts at the other, and from
whichever side the steam enters it pushes the valve over against the other side and
getting access to the outside of the valve keeps it against the cylinder port face and
also against the lateral port face which is for the time the exhaust port face.
We form the joint between the valve rod and the eccentric rod which works it, by
means of a pin fitted to fork eyes formed on the eccentric rod and made large enough

page_text: to allow of a hole for the valve rod being bored through the middle of it. When the
valve rod has been entered into its hole in the joint pin it is secured by a cutter,
without any other fastening being required.
The main connecting rod we also form with a forked end and joint pin but attach
the piston rod to it by a half bearing formed on the piston-rod end and a bearing cap
bolted to the piston-rod end. The piston-rod end is made with lateral projecting parts
which fit transverse grooves in slide plates fitted to work on the guides, and these
slide plates can be moved transversely into position before the bearing cap is bolted
on, but this cap
is made with lateral projections which when the cap is screwed home
enter recesses in the slide plates and lock them in position.
Dated this Tenth day of June 1886.
EDMUND HUNT,
Applicants' Agent.

page_text: COMPLETE SPECIFICATION.
Improvements in Steam Engines.
We, ROBERT RICHARDSON, Draughtsman, and STEPHEN ALLEY, of the firm of
Alley and Mac Lellan, Engineer, both of Sentinel Works, Polmadie, in the County
of Renfrew, North Britain, 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, that is to say:
Our said Invention has for its object to simplify and improve the construction of
steam engines having cylinders and reciprocating pistons.
In carrying out our Invention we employ a modification of an ordinary slide valve
for distributing steam to the ends of each cylinder, and in order to dispense with
complicated and troublesome valve gear we obtain a reversal of the motion of the
engine by means of a separate slide valve or a four-way cock controlling the steam
inlet passage, a passage leading to a condenser or the atmosphere, and two passages
communicating with each cylinder valve casing. These last named passages have ports
in the sides of the valve casing, there being a port face with the two cylinder ports
but without the usual middle port at the bottom of the casing. The slide valve is a
block made with two internal cavities which have ports at its opposite sides, one for
each of the ports in the sides of the casing; and the valve is made not to fit tightly
between the two sides of the casing but so as to be capable of a slight transverse
movement. The steam enters the valve casing at one side and exhausts at the other,
and from whichever side the steam enters it pushes the valve over against the other
side and getting access to the outside of the valve keeps it against the cylinder port
face and also against the lateral port face which is for the time the exhaust port face.
Our Invention also comprises an improved mode, hereinafter described, of con-
necting the valve rod to the eccentric rod which works it.
On an accompanying sheet of explanatory drawings our improvements are shown
as applied to steam-engine details combined with parts to form a steam steering
engine; but they are also applicable to simple motors or to winches or other machine
comprising steam-engine details.
Figure, 1, on the accompanying sheet of drawings is a sectional elevation.
Figure, 2, is a vertical section as at right angles to the middle part of figure, 1.
Figure, 3, is an enlarged horizontal section as taken through one of the cylinder
valve casings, and figure, 4, is a face view corresponding to figure, 3. Figures, 5,
and 6, are a face view and section of the valve; and figures, 7, and 8, are sectional
views as at right angles to each other of the joint connecting the valve rod and
eccentric rod. In these drawings the same reference numerals are used to mark the
same or like parts wherever they are repeated.
The machine comprises two steam cylinders, 9, the pistons of which are connected
The valve
in the usual way to cranks, 10, on the opposite end of a shaft, 11.
casings, 12, are on the sides of the cylinders, 9, facing each other and the two

page_text: covers, 13, are formed in one casting and connected by a part formed with four
passages, 14, 15, 16, 17. The outer passages, 14, 17, communicate with ports, 18, 19,
in the opposite sides of each valve casing, 12; and the two middle passages, which
are in one line communicate with flanged orifices, 20, 21, for the attachment of the
steam and exhaust pipes (not shown) and with ports, 22, 23, in a port face in a small
valve casing, 24, containing the reversing valve, 25, the same port face having also
in it ports communicating with the passages, 14, 17, leading to the cylinder valve
casings, 12. By moving the valve, 25, either of the passages, 14, 17, and corre-
sponding ports, 18, 19, in the cylinder valve casings, 12, can be made the steam inlet
the other one being the exhaust port and passage. Each cylinder port face is made
with only two ports leading to opposite ends of the cylinder; and the slide valve, 26,
is arranged to exhaust into one or other of the side ports, 18, 19. The slide valve, 26,
is made with two cavities formed with ports, 27, 28, at the sides, whilst the face of it
which works on the cylinder port face is made with a middle port, 29, communicating
with one cavity, and with two ports, 30, communicating with the other cavity. The
section in figure, 3, is taken as through one of the cylinder ports and one of the pair
of ports, 30, in the valve. The valve does not fit tightly between the sides of the
casing but is moved into contact with whichever side port, 18, or 19, is the exhaust
port for the time being, by the pressure of the steam entering the opposite side port,
and in consequence of this small movement the steam from whichever side it enters
has always access to the back of the valve so as to keep it against the cylinder port face.
The reversing valve, 25, may be moved in any convenient way, but in figure, 2, is
shown as controlled by parts of a well known kind in use in steering engines and to
which we do not make any claim. A. shaft, 31, turned by a hand wheel (not shown)
is by the action of a screw thread, 32, on it and working in the internally screwed
boss of a pinion, 33, made to move endways and through a lever, 34, to shift the
valve, 25. The pinion is in gear with a spurwheel (not shown) on the barrel or
pulley shaft of the machine, and when the engine moves, the pinion is turned so as to
tend to restore the shaft, 31, to its middle position.
We form the joint between each valve rod, 35, (figures, 7, 8,) and the eccentric
rod, 36, by means of a pin, 37, fitted to fork eyes formed on the eccentric rod, this
pin, 37, being made large enough to allow of a hole for the valve rod, 35, being bored
through the middle of it. When the valve rod, 35, has been entered into its hole in
the joint pin, 37, it is secured by a cutter, 38, without any other fastening being
required.
Having now particularly described and ascertained the nature of our said Invention
and in what manner the same is to be performed we declare that what we claim is:―
1-In reciprocating steam engines arranged to reverse by means of a separate valve
changing the inlet and exhaust passages communicating with each cylinder-valve
casing, the making of such casing and the slide valve with lateral inlet and exhaust
ports and fitting the valve so as to be movable to a slight extent from side to side
substantially as and for the purposes hereinbefore described.
2-The improved mode of connecting the valve rod to the eccentric rod substantially
as hereinbefore described.
Dated this Seventh day of March 1887.
EDMUND HUNT,
Applicants' Agent.