Improvements in or connected with Piston Valves and Ports or Passages for Steam or other Expansive Fluid Engines.
Year: 1897

page_text: Date of Application, 3rd Nov., 1897
Complete Specification Left, 28th July, 1898-Accepted, 17th Sept., 1898
Improvements in or connected with Piston Valves and Ports or
Passages for Steam or other Expansive Fluid Engines.
We, WILLIAM HORNSBY, DAVID ROBERTS, and CHARLES JAMES, Junior, all of
Spittlegate Ironworks, Grantham, in the County of Lincoln, Engineers, do hereby
declare the nature of this invention to be as follows:-
This invention relates to an improved method of arranging the piston valves
and passages or ports of steam or other expansive fluid engines in which as at
present constructed the cranks of the high and low pressure cylinders are placed
at an angle of 180° and wherein the steam or other expansive fluid is first admitted
to the high pressure cylinder and then passed over from the high to the low
pressure cylinder and from the low pressure cylinder to either a condenser or the
atmosphere by one valve worked by a suitable gear.
According to our invention we employ a hollow cylindrical valve with closed
ends, which has three ports or passages leading from its outer circumference to
its interior and arranged so that one of the ports or passages is at each end and
one in the centre of the valve, two grooves being formed round the outside of the
valve between each of the end and centre ports:
The valve chest has in the centre of its length two steam ports one of which
leads to one end of the high pressure cylinder and the other to the opposite end.
On each side of these high pressure steam ports are annular spaces into which
the steam or other expansive fluid from the boiler or reservoir enters, and on each'
side of these annular steam spaces and at the end of the valve chest are the ports
which lead straight into the low pressure cylinder.
The steam or other expansive fluid enters the annular spaces in the valve chest
and passes round the annular spaces outside the valve. The valve being moved
in either dindction allows the steam or expansive fluid to pass from one of the
annular spaces into the port leading to one end of the high pressure cylinder,
the centre port in the valve being then opposite the port leading to the other
end of the high pressure cylinder, which cylinder then exhausts into the centre
of the valve. The interior of this said valve forms an intermediate receiver, and
from this receiver the steam passes through one of the end ports of the valve
through the port into one end of the low pressure cylinder. The port at the other
end of the low pressure cylinder is now uncovered by one of the closed ends of
the valve and allows the cylinder to exhaust into the condenser or atmosphere.
By this invention we obtain the following advantages, a steam jacketted inter-
mediate receiver, reduced clearance spaces in the low pressure cylinder, equal
size clearance spaces in high pressure cylinder, reduced area of surface exposed to
the cooling action of the exhaust steam or condenser and reduced area of radiating
surfaces to the atmosphere with consequent increase of economy in the working
of the engine.

page_text: Improvements in or connected with Piston Valves and Ports or
Passages for Steam or other Expansive Fluid Engines.
We, WILLIAM HORNSBY, DAVID ROBERTS, and CHARLES JAMES, Junior, all of
Spittlegate Ironworks, Grantham, in the County of Lincoln, Engineers, do hereby
declare the nature of this invention and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement: :-
This invention relates to an improved method of arranging the piston valves
and passages or ports of steam or other expansive fluid engines in which, as at
present constructed, the cranks of the high and low pressure cylinders are placed
at an angle of 180° and wherein the steam or other expansive fluid is first admitted
to the high pressure cylinder and then passed over from the high to the low
pressure cylinder and from the low pressure cylinder to either a condenser or the
atmosphere by one valve worked by a suitable gear.
According to our invention we employ a hollow cylindrical valve with closed
ends, which has three ports or passages leading from its outer circumference to
its interior and arranged so that one of the ports or passages is at each end and
one in the centre of the valve, two grooves being formed round the outside of the
valve between each of the end and centre ports.
The valve chest has in the centre of its length two steam ports one of which
leads to one end of the high pressure cylinder and the other to the opposite end.
On each side of these high pressure steam ports are annular spaces into which
the steam or other expansive fluid from the boiler or reservoir enters, and on each
side of these annular steam spaces and at the end of the valve chest are the ports
which lead straight into the low pressure cylinder.
The steam or other expansive fluid enters the annular spaces in the valve chest
and passes round the annular spaces outside the valve. The valve being moved
in either direction allows the steam or expansive fluid to pass from one of the
annular spaces into the port leading to one end of the high pressure cylinder,
the centre port in the valve being then opposite the port leading to the other
end of the high pressure cylinder, which cylinder then exhausts into the centre
of the valve. The interior of this said valve forms an intermediate receiver, and
from this receiver the steam passes through one of the end ports of the valve
through the port into one end of the low pressure cylinder. The port at the other
end of the low pressure cylinder is now uncovered by one of the closed ends of
the valve and allows the cylinder to exhaust into the condenser or atmosphere.
To enable the invention to be fully understood we will describe it by reference
to the accompanying drawings, in which:
Figure 1 represents a longitudinal vertical section through the high and low
pressure cylinders of an engine of the kind described and fitted with our hollow
cylindrical valve and valve chest:
Figure 2 represents in vertical section the valve chamber with the valve removed,
also the steam and exhaust passages.
a is the high pressure cylinder, b the low pressure cylinder, c the high pressure
piston, the low pressure piston, e the hollow cylindrical valve with closed ends f
so as to form a receiver with three ports or passages leading from its outer cir-
cumference to its interior, g being the centre port or passage and h and h¹ the
two end ports or passages. j and are the two annular spaces formed round the
outside of the valve. k is the valve chest, and the two ports, one of which com-
municates with one end and the other with the opposite end of the high pressure

page_text: cylinder a. m and m¹ are the ports through which the live steam from the boilers
enters the two annular spaces j and j¹ formed around the hollow cylindrical valve e
and n and n¹ are the two ports or passages communicating respectively with the
two ends of the low pressure cylinder b. o is the live steam inlet from the boiler
to the passages p, p¹ around the valve chest k. q, q' are the exhaust passages
from the low pressure cylinder b, both leading into the exhaust pipes which
conveys the exhaust steam to the condenser or atmosphere.
In Figure 1 the high pressure piston c and the low pressure piston d are shewn
at one end of their strokes and the valve e in the position corresponding to the
position of the pistons.
Steam from the boiler enters the inlet o, passes into the passages p, p¹ which
are in connection with one another, thence through the passage m into the annular
space around the valve e from which it is admitted to the underside of the high
pressure piston c through the port / causing the said piston to ascend; at the same
time the steam, which is on the top side of this high pressure piston c, having
done its work, is exhausted through the port and the centre passage g into
the interior of the hollow cylindrical valve e which forms a receiver. From this
receiver it is admitted through the port h in the valve, and the port n to the top
of the low pressure piston d causing it to descend, the steam on the underside
of the said low pressure piston d having done its work being at the same time
exhausted either into the atmosphere or into a condenser through the port n¹
and over the end f of the hollow cylindrical valve e into the passage q and thence
into the exhaust pipe s.
A similar cycle of operations is gone through when the pistons travel in the
opposite direction.
By this invention we obtain the following advantages, a steam jacketted inter-
mediate receiver, reduced clearance spaces in the low pressure cylinder, equal size
clearance spaces in high pressure cylinder, reduced area of surface exposed to the
cooling action of the exhaust steam or condenser and reduced area of radiating
surfaces to the atmosphere with consequent increase of economy in the working
of the engine.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is:-
1. In a compound steam or other engine of the kind described the arrange-
ment of a hollow cylindrical piston valve having closed ends, a centre port, end
ports and annular spaces around the valve between the centre and end ports and
of a valve chest having two centre ports communicating with the high pressure
cylinder and end ports communicating with the low pressure cylinder and steam
inlet ports, substantially as, and for the purposes, hereinbefore described.
2. A piston valve for use with compound engines of the kind described con-
sisting of a hollow cylinder closed at both ends so as to form a receiver and having
a-centre port and end ports and annular spaces around the cylinder between the
centre and end ports, substantially as herein before described.
3. The improved valve gear hereinbefore described and illustrated in the accom-
panying drawing.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicants.