Improvements in or relating to Compound or Multiple Expansion Engines.
Year: 1899

page_text: Date of Application, 11th Sept., 1899
Complete Specification Left, 11th June, 1900-Accepted, 14th July. 1900
PROVISIONAL SPECIFICATION.
Improvements in or relating to Compound or Multiple Expansion
Engines.
I, CHARLES THOMAS CROWDEN, of Vernon Lodge, Eastnor Grove, Leamington
Spa, in the County of Warwick, Engineer, do hereby declare the nature of this
invention to be as follows:
This invention relates to compound or multiple expansion engines particularly
steam engines, and I will describe it as applied to a compound engine having
two cylinders, the exhaust of the one expanding into the second and larger
cylinder. The invention relates to the valve mechanism for controlling this
arrangement so that the engine may be worked as a compound, or both cylinders
can be worked direct with live steam in the boiler, both exhausting either into
the atmosphere or into a condenser.
The invention comprises a valve of the cylindrical or piston type working in a
corresponding casing, the exhaust passage from the high pressure cylinder enter-
ing the casing by one port and continuing by another one to the low pressure
cylinder. When the valve is in one position there is a clear through-way for
the steam from the high pressure cylinder through both ports to the low pressure
cylinder, but when the position of the valve is altered the through-way is stopped
and the exhaust from the high pressure cylinder passes to the atmosphere or con-
denser by way of the ports, while the other port is opened to live steam. This
may be conveniently carried out in the following manner:-
The casing is bored cylindrically and has three projecting collars or faces with
which the operating portions of the valve engage. The valve consists of two
heads and a smaller connecting central or junction piece around which latter
the steam can freely pass. The position of the valve for working as a compound
engine is when the two heads of the valve engage with the two outside collars
of the valve casing, the reduced central portion of the valve allowing the steam
o freely pass into the casing and out again by the two ports, as above explained.
To alter the engine so that it ceases to be a compound the valve is moved endwise
until one of its heads engages with the central collar of the casing, thus forming
block between the two ports. At the same time the other valve head has been
noved from the outside collar with which
ort leading to the air or condenser, and the exhaust port from the high pressure
was engaged so as to uncover another
ylinder is, with the valve in this position, in direct communication with this
xhaust passage. The movement of the valve has removed the head first described
rom the outside collar of the casing with which it was engaged, and has thus
nclosed a passage for live steam from a port in the casing to the second of the
vo previously mentioned ports so that instead of the exhaust steam from the
igh pressure cylinder passing to the valve chest of the low pressure cylinder,
e live steam now takes that course.
The valve which is provided with means for operating it, (conveniently in the
rm of a spindle passing through a stuffing box in the casing) may be operated
tirely mechanically, or partly mechanically and partly be the in

page_text: or entirely by the steam pressure. In the latter case a bye-pass and cock or other
form of valve would permit of steam pressure being applied to either end of the
valve for the purpose of moving it.
To operate the valve mechanically the spindle can be connected with any suitable
hand-operated lever or with the governor, if preferred, so that if the speed of
the engine is reduced to a certain limit the governor would automatically move
the valve and admit steam direct to the low pressure cylinder.
Where steam was used in addition to the mechanical means this would be
accomplished by a combination of the two arrangements.
The spindle of the valve may be extended in both directions, one terminating
in a jaw to receive the lever etc. and the other working in a closed casing in the
manner well-known to engineers. The casing may be made self-contained and
complete to be bolted on to a suitable part of the cylinder, so that the two ports
of the casing fit over the corresponding ports of the cylinder with which the casing
makes a tight joint.
COMPLETE SPECIFICATION,
Improvements in or relating to Compound or Multiple Expansion
Engines.
I, CHARLES THOMAS CROWDEN, of Vernon Lodge, Eastnor Grove, Leamington
Spa, in the County of Warwick, Engineer, 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 relates to compound or multiple expansion engines particularly
steam engines, and I will describe it as applied to a compound engine having
two cylinders, the exhaust of the one expanding into the second and larger
cylinder. The invention relates to the valve mechanism for controlling this
arrangement so. that the engine may be worked as a compound, or both cylinders
can be worked direct with live steam from the boiler, both exhausting either into
the atmosphere or to a condenser.
The invention comprises a valve of the cylindrical or piston type working in a
corresponding casing, the exhaust passage from the high pressure cylinder enter-
ing the casing by one port and continuing by another one to the low pressure
cylinder. When the valve is in one position there is a clear through-way for
the steam from the high pressure cylinder through both ports to the low pressure
cylinder, but when the position of the valve is altered the through-way is stopped
and the exhaust from the high pressure cylinder passes to the atmosphere or con-
denser by way of one port, while the other port is opened to live steam.
In the accompanying drawings which illustrate two methods of applying this
invention.
Figure 1 is a view through a longitudinal central section of the valve casing,
and of a transverse section through the cylinders showing the required position
of the valve for the engine to be compound.
Figure 2, is a longitudinal central sectional view through the valve casing
showing the valve moved to the position required for the engine to work with
simple expansion..

page_text: Figure 3, is a longitudinal central sectional view through the valve casing
showing the valve as operated by steam pressure; when the valve is in the
position shown by full lines the engine will be compound, and when as shown
by chain lines the engine will work with simple expansion.
Like letters indicate like parts throughout the drawings.
The valve casing A is bored cylindrically and has projecting collars or cylindric
faces A¹ A2 and A³ in which the pistons B1 and B2 of a valve B fit. The cas-
ing A has four ports viz-a port C being an outlet from the valve-chest of the
high pressure cylinder G another port D an inlet to the valve-chest of the low
pressure cylinder H, an inlet for live steam to the valve-casing A is supplied by
a port E, while a port F is an outlet to the air or condenser. The valve B
consists of two heads or pistons B¹ and 132 and a smaller connecting piece B³
around which steam can freely pass, it is also provided with means for operating
it in the form of a spindle B passing through a stuffing box A4 in the casing A,
as in Figures 1 and 2 one end of the spindle B is screwed and passes through
a threaded perforation in a supporting bracket J which constitutes a nut for the
screwed portion of the spindle 134, hand-wheel B is attached to this end; the
other end of the spindle B of the valve B may be extended and made to work
in a closed guide A5. When the valve is to be operated by steam as in Figure 3
the valve B is constructed with an auxilliary piston B6 working in an extended
portion A of the casing A in place of the screwed spindle B and hand-wheel B³.
The operation of the valve B is as follows:-
To work the engine as a compound the valve B must be placed as in Figure 1
so that its two pistons B1 and B2 engage with the two outside collars A¹ and A³
of the casing A. Exhaust steam from the valve-chest of the high pressure
cylinder G will now flow through the port C around the central portion 133 of
the valve B and from thence through the port D to the valve chest of the low
pressure cylinder H. To alter the valve B so that the engine ceases to be a com-
pound, the valve B is moved endwise to the position shown in Figure 2, when one
of its pistons 132 engages with the central collar A2 of the casing A, thus blocking
the way between the two ports C and D and at the same time putting the port E
in direct communication with the port D, this movement also causes the other
piston B¹ of the valve B to be moved clear of the collar A¹ thus opening a passage
from the port C to the port F. Live steam may now pass through the port E
around the spindle 13 of the valve B and into the valve-chest of the low pressure
cylinder H by way of the port D, and also the exhaust from the high pressure
cylinder G will flow through the port C around the central portion B3 of the
valve B and out through the port to the air or condenser.
Therefore the result of this movement of the valve B is that live steam is
supplied to the valve chest of the low pressure cylinder H in place of exhaust
steam from the valve chest of the high pressure cylinder G, and that the exhaust
steam from the valve-chest of the high pressure cylinder G passes direct to the
air or condenser, instead of into the valve-chest of the low pressure cylinder H.
Thus both cylinders are receiving live steam and exhausting direct to the air
or condenser, as in a simple expansion engine.
The valve B may be-operated by steam pressure as in Figure 3 in the following
manner:
To move the valve B from right to left, steam is let in at the port E by a valve
not shown in the drawing; its pressure acting on the outside face of the piston B²
will force the valve B in the direction indicated by the arrow until the piston B²
engages with the inner collar A² of the casing A.
To move the valve B from left to right the supply of steam at E is shut off
and steam pressure under the control of a suitable valve or cock is applied to the
outside face of the piston B6 moving the valve B back to its original position.
The casing A may be made self-contained and complete to be bolted on to a
suitable part of the cylinder so that the two ports C and D fit over the corre-
sponding parts of the cylinder with which the casing A makes a tight joint.

page_text: 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
1. In a compound engine the combination with the steam passages leading
from the high pressure cylinder and to the low pressure cylinder and a piston
valve controlling those passages of a passage such as E (Figure 3) for live steam
which besides supplying the larger cylinder when the engine is not working as
a compound also operates the piston valve.
2. In a compound engine a piston valve and conduits arranged and operating
substantially as and for the purpose described and illustrated in Figures 1 and 2
of the accompanying drawings.
3. In a compound engine a steam operated valve and conduits arranged and
operating substantially as and for the purpose described and illustrated in Figure 3
of the accompanying drawings.
Date this 11th day of Luno 1900
BOULT, WADE & KILBURN,
Agents for the Applicant.