Improvements in Direct Acting Engines.
Year: 1895

page_text: Date of Application, 30th Nov., 1895
Complete Specification Left. 24th Aug. 1896-Accepted. 10th Oct.. 1896
Improvements in Direct Acting Engines.
We, EDMUND HOWL, of The Quarries, near Dudley, Engineer, and WALTER
WATKINS ATTWOOD, of 16, Castle Street, Tipton, Engineer, both in the County
of Stafford, do hereby declare the nature of this invention to be as follows:-
This invention consists of improvements relating to direct acting engines, our
object being to construct and arrange a simple and effective valve and valve
operating appliances for controlling the admission and release of steam or other
working fluid.
In the application of our invention to a single cylinder compound direct acting
steam pump, we provide a double headed piston to work within the steam cylinder,
and arrange for the steam to exhaust from one side of the piston heads to the
other. The cylinder is divided into two equal parts by an inner annular projection,
and within each portion or end of the cylinder we provide two unequal piston
areas on which the steam operates the smaller area consisting of the annular
space between the body of the piston and the cylinder walls, the entire area of
the piston or bore of the cylinder providing the larger piston area. We form
two ports for the admission of steam to the annular spaces, or to the high
pressure area, from the valve chest, and two ports through which the steam flows
from the inner to the outer sides of the piston heads or to the low pressure area.
The exhaust steam from the two larger areas passes through exhaust ports formed
in the valve face to the condenser or to the atmosphere. Suitable cavities are
made in the valve to form the connections between the ports on the reciprocation
of the valve across its face or seating.
The reciprocation of the valve is obtained by means of a valve rod loosely
attached to the valve and having a head formed upon each end of the same
which fits within chambers at the ends of the valve chest. A connecting tube
or passage is formed between the ends of the valve chest chambers and the ends
of the cylinder, the positions of the openings into the cylinder being so fixed
that when the double headed piston reaches the end of its stroke in either
direction the opening is uncovered to the high pressure steam, and an unequal
pressure being thus brought upon the ends of the valve rod, the valve is forced
across its face by the higher pressure and a change in the distribution of steam
is effected. Violent stoppage of the cylinder piston and also of the valve rod
is prevented by a cushioning action at each end of the stroke which we obtain
by the provision of a space between the openings into the cylinder aid in the
valve chest chambers, and the ends of the cylinders and chambers.
The steam moved valve is in this instance operated by the attachment of a
pipe from the steam cylinder to the valve chest, and we insert a cock in this
pipe to regulate the steam and exhaust from the front end of the valve.
We sometimes dispense with an independent valve rod such as hereinbefore
described, and form the circular heads or pistons in one piece or casting with
the valve itself.
The piston rod attached to the double headed piston passes through a stuffing
box at the head of the cylinder in the usual manner, and is attached at its opposite
end directly to the pump plunger of any ordinary and well known type, the
construction and arrangement of the pump end of the engine forming no part of
this invention.

page_text: In the construction of a duplex type compound direct acting steam pump or
pumping engine, in accordance with our invention, we employ a double headed
piston to work within each of the steam cylinders, and divide each cylinder into
two parts by means of an internal annular projection as hereinbefore described.
We also arrange the ports for the admission of steam to the high pressure area
of the piston, and for the expansion of the steam on to the low pressure area,
also for the exhaust from the latter area, in the same manner as with the single
cylinder engine. Instead, however, of employing a steam moved valve for con-
trolling the distribution of steam through the ports we drive the valve of each
cylinder by a positive motion obtained by means of levers and connections with
the piston rods as with an ordinary duplex type pump.
We adapt the duplex type pumping engine for quadruple expansion of the steam,
by conveying the steam from one cylinder to the other, the two cylinders being
then made of unequal diameters to provide four increasing areas or capacities
through which the steam passes before discharge to a condenser or to the
atmosphere.
In order to adapt a duplex type pumping engine so that in the event of
breakdown of one side, the opposite or adjacent side may be worked as a single
cylinder direct acting pump, we fit each cylinder both with a positive and a steam
moved valve apparatus, arranging the same in such a manner as to permit of very
ready connection and disconnection with the valve. The positive motion is
obtained by connection with the piston rods in any ordinary manner, whilst the
apparatus for working the valve by steam is arranged in the manner as berein-
before described.
We do not limit the application of our invention to any particular type of direct
acting engine, but adapt the same in the construction of engines for varying
services, making such modifications as may be necessary to obtain the most efficient
working.
1 L
1
MARKS & CLERK,
18 Southampton Buildings, London, W.C., and
13 Temple Street, Birmingham, Agents for the Applicants.
Improvements in Direct Acting Engines.
We, EDMUND HOWL, of The Quarries, near Dudley, Engineer, and WALTER
WATKINS ATTWOOD, of 16, Castle Street, Tipton, Engineer, both in the County
of Stafford, 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 consists of improvements relating to direct acting engines, our
object being to construct and arrange a simple and effective valve and also valve
operating appliances for controlling the admission and release of steam or other
working fluid.
Referring to the two accompanying sheets of drawings;
Figures 1 and 2 Sheet are respectively longitudinal and transverse sections of
a single cylinder compound direct acting engine, and
Figures 3 and 4 Sheet 2 are respectively part sectional side and end elevations
illustrating a duplex compound engine fitted in accordance with our invention each
side being arranged for operating as a single cylinder compound in the event of
either cylinder breaking down.
In the application of our invention to a single cylinder compound direct acting

page_text: steam pump (see Figures 1 and 2) we provide a double headed trunk piston A A'
to work within the steam cylinder B, and arrange for the steam to exhaust from
one side of each of the piston heads to the other. The cylinder B is divided into
two equal parts by an inner annular projection C, and within each portion or end
of the cylinder we provide two unequal piston areas on which the steam operates
the smaller area consisting of the annular space between the annular projection or
body C of the piston and the cylinder walls, the entire area of the piston or bore
of the cylinder providing the larger piston area. We form two ports D D' for
the admission of steam to the annular spaces, or to the high pressure area from the
valve chest, and two ports E E' through which the steam flows from the inner to
the outer sides of the piston heads A A¹ or to the low pressure area. The exhaust
steam from the two larger areas passes through exhaust ports F F formed in the
valve face to the condenser or to the atmosphere, suitable cavities G G and K K¹
are made in the piston valve H H' to form the connections between the ports on
the reciprocation of the valve across its face or seating.
The cavities G G₁ in the piston valves H H are exhaust cavities, and K K¹ are
cavities with ports for passing the steam from the high pressure to the low pressure
spaces. The valves H H are connected by a bridge piece J so as to operate
together.
The reciprocation of the valves H H¹ may be obtained by means of a valve rod
loosely attached to the valves and having a head formed upon each end of the same
which fits within chambers at the ends of the valve chest. But we prefer to use
for this purpose the ends of the valve itself. Connecting tubes L L are formed
between the ends of the valve chest chambers and the ends of the cylinder, the
positions of the openings into the cylinder being so fixed that when the double
headed piston valve H H reaches the end of its stroke in either direction the
opening is uncovered to the high pressure steam, and an unequal pressure being
thus brought upon the euds of the piston valve, the valve is forced across its face
by the higher pressure and a change in the distribution of steam is effected.
Violent stoppage of the cylinder piston and also of the piston valve is prevented
by a cushioning action at each end of the stroke which we obtain by the provision
of a space between the openings into the cylinder and in the valve chest chambers,
and the ends of the cylinders and chambers.
The steam moved valve is in this instance operated by the attachment of the
pipes L L from the steam cylinder to the valve chest, and we insert cocks in these
pipes to regulate the steam and exhaust from the front end of the valve.
The piston rod M attached to the double beaded piston passes through a stuffing
box at the head of the cylinder in the usual manner, and is attached at its opposite
end directly to the pump plunger of any ordinary and well known type, the
construction and arrangement of the pump end of the engine forming no part of
this invention.
In the construction of a duplex type compound direct acting steam pump or
pumping engine (see Figures 3 and 4) in accordance with our invention, we employ
a double headed trunk piston to work within each of the steam cylinders, and
divide each cylinder into two parts by means of an internal annular projection as
hereinbefore described. We also arrange the ports for the admission of steam to
the high pressure area of the piston, and for the expansion of the steam on to the
low pressure area, also for the exhaust from the latter area, in the same manner as
with the single cylinder engine. Instead, however, of employing a steam moved
valve for controlling the distribution of steam through the ports we drive the
valve of each cylinder by a positive motion obtained by means of levers and
connections with the piston rods as with an ordinary duplex type pump. These
levers are shown at NO and N¹ O' connecting between the valve of one cylinder
and the piston rod of the other.
We adapt the duplex type pumping engine for quadruple expansion of the
steam, by conveying the steam from one cylinder to the other, the two cylinders
being then made of unequal diameters to provide four increasing areas or

page_text: capacities through which the steam passes before discharge to a condenser or to
the atmosphere.
In order to adapt a duplex type pumping engine so that in the event of
breakdown of one side, the opposite or adjacent side may he worked as a single
cylinder direct acting pump, we fit each cylinder both with a positive and a steam
moved valve apparatus, arranging the same in such a manner as to permit of very
ready connection and disconnection with the valve. The positive motion is
obtained by connection with the piston rods in any ordinary manner, whilst the
apparatus for working the valve by steam is arranged in the manner as herein-
before described.
We do not limit the application of our invention to any particular type of direct
acting engine, but adapt the same in the construction of engines for varying
services, making such modifications as may be necessary to obtain the most efficient
working.
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 direct acting engines the combination with a single cylinder having a
double headed trunk piston working therein and a valve face provided with three
pairs of ports, of a piston valve operated by high pressure steam from the cylinder,
substantially as herein described.
2. A single cylinder compound direct acting engine arranged and operating
substantially as hereinbefore described with reference to Figures 1 and 2 of the
drawings.
'
3. The construction and arrangement of a duplex direct acting engine in which
each cylinder is fitted with a double headed trunk piston and provided with a
valve face having three pairs of ports, the distribution of the steam in each
cylinder being controlled by a positively moved piston valve substantially as
herein before described with reference to Figures 3 and 4 of the drawings.
4. A duplex direct acting engine in which each cylinder is fitted with a double
headed trunk piston and provided with a valve face having three pairs of ports,
the distribution of the steam in each cylinder being controlled by a valve which
can be separately operated by steam if required while usually actuated by
positively moved levers substantially as herein described.
Dated this 22nd day of August 1896.
MARKS & CLERK,
18 Southampton Buildings, London, W.C., and
13 Temple Street, Birmingham, Agents for the Applicants.