IMPROVEMENTS
Year: 1878

page_text: PROVISIONAL SPECIFICATION left by the said Druitt Halpin at the Office
of the Commissioners of Patents on the 3rd September 1878.
DRUITT HALPIN, of Old Charlton, in the County of Kent.
STEAM ENGINES."
"IMPROVEMENTS IN
My Invention has for object improvements in steam engines.
One part of my Invention has reference to compound engines wherein each
cylinder sorves as a compound or high and low pressure cylinder. The piston has
at one end an extension of smaller diameter than the piston itself. At the
corresponding end of the cylinder the cylinder cover has a cavity or case with an
air valve opening outward, in which the extension of the piston works, thus an
approximate vacuum is established, as the extension above mentioned is withdrawn
from the chamber. By this arrangement an annular area of piston is presented
which is less (by the area of the cross section of the extension) than the area of the
opposite face of the piston. The live steam from the boiler is admitted into the
annular space surrounding the extension of the piston, and operates against the
annular piston face, being cut off at any desired part of the stroke. Having done
its work on the annular or high pressure side of the piston, the steam is exhausted
thence into the opposite or low pressure end of the cylinder; the steam may for
this purpose pass through a passage or passages in the piston itself, controlled by a
valve or valves suitably operated; or suitable passages with appropriate valves may
be arranged in the body of or externally of the cylinder.
The steam having done duty in the low pressure end of the cylinder is exhausted
through a suitable exhaust port. Thus it will be understood each stroke in one
direction is effected by steam of the higher pressure acting against the annular face

page_text: of the piston, and in the contrary direction by steam of the lower pressure acting
on the opposite or larger face of the same piston.
The depth of piston may in some cases advantageously equal the stroke.
The arrangement may be modified by providing the cylinder cover with a
displacement piece projecting into a corresponding cavity in the piston. Some-
times I surround the cylinder with a steam jacket or case such as is herein-after
described.
In order to transmit as much heat as possible from the steam in the jacket to the
stean inside the cylinder, I cast longitudinal or circumferential ribs or projections
on the cylinder.
According to another part of my Invention a cylinder or cylinders, cast with
appropriate steam and exhaust ports, is or are arranged within and secured to a
steam case or jacket, the steam surrounding the cylinder or cylinders.
The cylinder cover or covers at one end is or are secured by dogs (or bolts) so as
to be readily removeable. The steam case or jacket at the one end is provided with
a cover, by removing which the cylinder cover or covers at that end is or are exposed;
and by then removing the dogs (or bolts) and cylinder cover or covers the piston or
pistons and cylinder or cylindera can be inspected, &c.
Cylinders combined with jackets as just described may be used for engines of
various constructions.
In applying the arrangement in a portable engine I provide at the lower side of
the jacket a suitable pipe which acts as a foot to support the jacket, and contains
the stop and throttle valves for admitting steam to the jacket. I bolt the end of
this jacket directly to a bifurcated Corliss frame so that the whole of the strains
generated in the engine shall be self-contained and perfectly independent of any
partial and extraneous aid from the boiler.
I construct a stationary self-contained engine as follows:-A bed plate containing
condensor (jet or surface) has flanges at one end; these carry overbung cylinders
having two Corliss arms, between which the fly wheel revolves. The air pump is
vertical, and the whole engine is perfectly self-contained, both as regards strains
and foundations.
By slight modification such an engine may be constructed to operate as a com-
pound engine, the relative sizes of the two cylinders and the valvo arrangement
being varied accordingly.
I arrange automatic expansion gear suitable for engines such as above referred to
as follows:-Through each distribution valve I form passages made with a twist,
the openings at the face adjacent to the cylinder being at right angles to the cylinder
axis, whilst at the back of the valve the apertures are obliquo in a converging
direction. The cut-off valve is of a tapering or doubly inclined form, and is able to
traverse or reciprocate upon the distribution valve in a direction at right angles to
the motion of the latter. A spring or equivalent means arranged at one end tends
to move the cut-off valve in one direction; in the reverse direction it is operated
from the governor spindle by a frustum of a cone which rotates in contact with an
antifriction roller carried by the valve spindle. The cone is able to move endwiso
along the governor spindle, but by a key and groove is compelled to rotate with it.
The governor spindle is parallel or at an angle to the periphery of the cone, and is
connected to the governor so as to be operated by it. The governor spindle is
driven by bevil gear from the main shaft.
It will be evident that my improved arrangements of steam cylinders may be
used without my improved valve arrangement, and that the latter may be used in
ongines differing in other respects from those described.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Druitt Halpin in the Great Seal Patent Office on the 3rd March
1879.
DRUITT HALPIN, of Old Charlton, in the County of Kent. "IMPROVEMENTS IN
STEAM ENGINES."
One part of my Invention has reference to compound engines, wherein each
cylinder serves as a compound or high and low pressure cylinder. The piston has
at one end an extension of smaller diameter than the piston itself. At the corre-
sponding end of the cylinder, the cylinder cover has a cavity or case, with an air
valve opening outwards, in which the extension of the piston works, thus an approxi-
mate vacuum is established, as the extension above mentioned is withdrawn from the
chamber. By this arrangement an annular area of piston is presented, which is
less (by the area of the cross section of the extension) than the area of the opposite
face of the piston. The live steam from the boiler is admitted into the annular
space surrounding the extension of the piston, and operates against the annular
piston face, being cut off at any desired part of the stroke. Having dono its work
on the annular or high-pressure side of the piston, the steam is exhausted thence
into the opposito or low-pressure end of the cylinder. The steam may for this
purpose pass through a passage or passages in the piston itself, controlled by a
valve or valves suitably operated; or suitable passages with appropriate valves
may be arranged in the body of or externally of the cylinder.
The steam having done duty in the low-pressure end of the cylinder is exhausted
through a suitable exhaust port. Thus it will be understood each stroke in one
direction is effected by steam of the higher pressure acting against the annular face
of the piston, and in the contrary direction by steam of the lower pressure acting
on the opposite or larger face of the same piston.
The depth of piston may in some cases advantageously equal the stroke.
The arrangement may be modified by providing the cylinder cover with a dis-
placement piece projecting into a corresponding cavity in the piston. Sometimes
I surround the cylinder with a steam jacket or case, such as is herein-after
described.
In order to transmit as much heat as possible from the steam in the jacket to
the steam inside the cylinder I cast longitudinal or circumferential ribs or pro-
jections on the cylinder.
According to another part of my Invention a cylinder or cylinders cast with
appropriate steam and exhaust ports is or are arranged within and secured to a
stenm case or jacket, the steam surrounding the cylinder or cylinders.
The cylinder cover or covers at one end is or are secured by dogs (or bolts) so as
to be readily removable. The steam case or jacket at the one end is provided with
a cover, by removing which the cylinder cover or covers at that end is or are
exposed, and by then removing the dogs (or bolts) and cylinder cover or covers the
piston or pistons and cylinder or cylinders can be inspected, &c.
Cylinders combined with jackets, as just described, may be used for engines of
various constructions.
In applying the arrangement in a portable engine I provide at the lower side of
the jacket a suitable pipe, which acts as a foot to support the jacket, and contains
the stop and throttle valves for admitting steam to the jacket. I connect the end
of the jacket directly with a bifurcated Corliss frame, so that the whole of the
strains generated in the engine shall be self-contained, and perfectly independent
of any partial and extraneous aid from the boiler.
I construct a stationary self-contained engine as follows:-A bed plate containing
condenser (jet or surface) has a flange at one end, which carries overhung cylinders,
and has two Corliss arms, between which the fly wheel revolves. The air pump is

page_text: vertical, and the whole engine is perfectly self-contained, both as regards strains
and foundations.
By slight modification such an engine may be constructed to operate as a com-
pound engine, the relative sizes of the two cylinders and the valve arrangement
being varied accordingly.
I arrange automatic expansion gear suitable for engines, such as above referred
to, as follows:-Through each distribution valve I form passages made with a
twist, the openings at the face adjacent to the cylinder being at right angles to the
cylinder axis, whilst at the back of the valve the apertures are oblique in a con-
verging direction. The cut-off valve is of a tapering or doubly-inclined form, and
is able to traverse or reciprocate upon the distribution valve in a direction at right
angles to the motion of the latter. A spring or equivalent means arranged at one
end tends to move the cut-off valve in one direction; in the reverse direction it is
operated from the governor spindle by a frustum of a cone, which rotates in
contact with an antifriction roller carried by the valve spindle. The cone is able
to move endwise along the governor spindle, but by a key and groove is compelled
to rotate with it. The governor spindle is parallel to one side of the cone, and is
connected to the governor so as to be operated by it. The governor spindle is
driven by bevil gear from the main shaft.
It will be evident that my improved arrangements of steam cylinders may be
used without my improved valve arrangement, and that the latter may be used in
engines differing in other respects from those described.
Referring to the accompanying Drawings, Fig. 1 shews part of a compound
engine according to my Invention, in which the piston has at one end an extension
of smaller diamenter than the piston itself, and the cover of the same end of the
cylinder has a cavity or case with an air valvo opening outward, in which cavity
or case the extension of the piston works, cach stroke in one direction being effected
by steam of the higher pressure acting against the annular face of the piston, and
in the contrary direction by steam of the lower pressure acting on the opposite or
larger face of the same piston.
A is the cylinder; B, the piston; C, the piston rod. On to the piston B I bolt the
trunk D, the upper part of which works in the cap or bonnet E; F is a non-return
valve, open to the atmosphere for discharging the air contained in the space G
when work is commenced. Steam is first admitted into the annular space H, where
it is partially expanded, and subsequently led round to the other side of the piston
working against the whole area of the piston in space I.
This Drawing shews how I convert an existing non-compound engine into a
compound engine.
A new compound engine may be similarly constructed, but I should then arrange
the valve face differently, as for example, in the manner shewn in Fig. 4.
To continue my description of Fig. 1, K is the original valve face, on to which,
in order to obtain the necessary altered distribution of the steam, I bolt the false
face L. Steam is admitted and exhausted through the valve M, and the expansion
is controlled by the valve N.
Fig. 2 shews a modification in which A is the ordinary cylinder of an existing
engine, which I wish to compound in accordance with my Invention.
On to the piston B I bolt the trunk C, and I envelope the upper part of this
trunk with a bonnet or cap D. E is the stuffing box. The high-pressure steam is
first admitted into the annular space F, where it is partially expanded. It is subse-
quently admitted to the full area below the piston in the space G, where further
expansion takes place.
Fig. 3 shews a side elevation partly in section, and Fig. 4 a plan partly in hori-
zontal section of another arrangement of single cylinder compound engine according
to my Invention.
This engine embraces the following features:-The cylinder cover is provided
with a displacement piece projecting into a corresponding cavity in the piston; the
cylinder is surrounded with a steam jacket or case, steam surrounding the cylinder;

page_text: the cylinder cover at one end is secured by bolts, so as to be readily removeable; tho
steam case or jacket at the same end is provided with a cover, by removing which
the cylinder cover is exposed, and can be readily removed so as to expose the piston.
Ribs or projections are cast on the cylinder to transmit heat from the steam in the
jacket to the steam inside the cylinder. The bed plate, which contains the con-
densor, has a flange at one end, which carries the cylinder overhung, and has two
Corliss arms, between which the fly wheel revolves. The air pump is vertical, and
the whole engine is perfectly self-contained, both as regards strains and foundations.
A is the cylinder; C, tho condenser; E, E, are the Corliss arms; F is a disc crank;
G, the crank shaft; H, the fly wheel; D, the air pump.
The action of the steam is as follows:-It enters the annular spaco I through the
steam port K, and having acted on the prolongation L' of the piston L in driving
it away from the centre of the crank shaft; the steam is then exhausted through the
exhaust port M of the distribution valve, the steam port N and the port O in the
valvo at the low-pressure end of the cylinder, and enters the cylinder at the end P,
where it acts on the large area of the piston. Having done its work on this end it
is exhausted through the port Q in the ordinary manner into the condenser. R is
the displacement trunk fastened to the cylinder, round which the annular pro-
longation L' of the piston L works; U is the self-acting valve opening outwards
and discharging into the air to permit of the escape of air when work begins in the
space L'; this air is discharged through the pipe T; V is the cut-off valve or
expansion slide on the back of the distribution valve or slide M*, cutting off the
steam by means of the vertical motion communicated to it by the spindle X,
depressed by a frustum of a cone Y revolving and sliding on the shaft Z driven by
bevel wheels from the crank shaft. The position of the frustum of the cone Y is
controlled, as shewn, by the small hand wheel e, and the distribution of steam in
this engine is not under the control of the governor.
Figs. 5 and 6 shew a portable engine constructed according to my Invention,
Fig. 5 being a vertical longitudinal section, and Fig. 6 a plan.
This engine embraces the following features:-The cylinder is surrounded with a
steam jacket or case, steam surrounding the cylinder; the cylinder cover at one end
is secured by bolts, so as to be readily removeable; the steam case or jacket at the
same end is provided with a cover, by removing which the cylinder cover is exposed,
and can be readily removed so as to expose the piston. Ribs or projections are cast
on the cylinder to transmit heat from tho steam in the jacket to the steam inside
the cylinder. A suitable pipe at the lower side of the jacket acts as a foot to
support the jacket, and may contain the stop and throttle valves for admitting steam
to the jacket, where the engine is not provided, as shewn, with automatic expansion
gear. The end of the said jacket is connected directly with a bifurcated Corliss
frame, so that the whole of the strains generated in the engine shall be self-contained
and perfectly independent of any partial and extraneous aid from the boiler. A is
the boiler, which may be of any of the well-known constructions; B is the cylinder,
completely enclosed in the steam jacket C by the casing D, this casing being formed
by a prolongation of the main bifurcated Corliss frame E of the engine; F is tho
cylinder cover, and G the cover at the end of the steam jacket for giving admittance
to the cylinder cover.
The distribution of steam is controlled by means of a distribution valve, driven
by the eccentric H keyed on the shaft in the usual manner, and the expansion is
controlled by the governor I regulating the position of the frustum of a cone K, and
so operating a suitable valve arrangement, which may be either of the kind
illustrated in Figs. 8 and 9, or as illustrated in Figs. 10 and 11.
In the arrangement shewn in Figa 8 and 9 the expansion is produced by the use
of one valve only, a double motion being communicated for the purpose to this
valve. A is the valve, and it receives the ordinary reciprocation inotion through
the valve rod Band the buckle E.
When steam is to be admitted to the engine for the maximum period of admission
desired, the motion of the valve is controlled only by the valve rod B, and this

page_text: motion is consequently only in one direction. When, however, an earlier cut-off
is desired, the reciprocating motion is given by means of the frustum of a cone
(Figs. 5 and 6) revolving on the shaft, and whose longitudinal motion on that shaft
is controlled by the governor to the vertical spindle F, which is fixed to the
buckle G.
This latter vertical motion, in combination with the before-described horizontal
reciprocating motion of the valve, produces a travel of the valve in the form of a
more or less flattened ellipse, and the cut-off of the steam is effected by the sloping
outer edges of the valve meeting the edges of the ports.
In order to lessen the vertical motion of the valve, the steam ports are divided
when approaching the valve face, and are by preference of a triangular form.
In Figs. 10 and 11, the valve A has a reciprocating motion communicated to it by
the valve spindle B; this valve spindle is connected to a round hoop buckle C, this
buckle being bored out so as to fit over a corresponding projection on the back of
the valve, which projection of course forms the exhaust cavity. Any desired degree
of expansion may bo produced by this valve by imparting to it a rocking motion.
This rocking motion is produced by the movement of the spindle D, as before
described. This spindle D is connected at its lower end to a slotted link E, in which
works a block F grasping a pin G; this pin is fixed eccentrically in the back of
the slide valve. The combined motion of the valve spindle B and of the vertical
expansion spindle D produces the necessary sliding and slewing motion in the valve
to effect the cut-off at any desired point.
Referring again to Figs. 5 and 6, the engine frame is bolted firinly to the top of
the boiler at L, where the steam stop valvo may also be conveniently placed, and
the feet M, M, at the other end of the Corliss frame, resting on the boiler or bolted
to it, are free to slide on the boiler, to allow for the expansion of the latter when
steam is got up, thus keeping the whole of the strains in the engine self contained,
and allowing the boiler to expand without reference to the engine; N is the crank
shaft; O, the fly wheel; P are the ribs on the sides and ends of the cylinder, and
its cover for transmitting heat from the steam in the jacket to the steam working
in the cylinder.
Figs. 12, 13, 14, and 15 shew a compound engine according to my Invention,
Fig. 12 being a longitudinal section through the centres of the air pump, condenser,
and steam jacket; Fig. 13, a plan partly in section; Fig. 14, a vertical cross
section through the cylinders; and Fig. 15, a vertical cross section through the
condenser.
This engine embraces the following features:-The cylinders cast with appropriate
steam and exhaust ports, and with heat-transmitting ribs or projections are arranged
within a steam caso or jacket, the steam surrounding the cylinders. The cylinder
covers at one end are secured by bolts, so as to be readily removeable; the steam
case or jacket at the one end is provided with a cover, by removing which the
cylinder covers at that end are exposed, and by then removing the bolts and cylinder
covers, the pistons and cylinders can be inspected, &c.
The bed plate containing the condenser has a flange at one end, which carries the
cylinders overhung, and has two Corliss arms, between which the fly wheel revolves,
the air pump is vertical, and the whole engine is perfectly self contained, both as
regards strains and foundations.
.
The distribution valve of the high-pressure cylinder has formed through it
passages made with a twist, the openings at the face adjacent to the cylinder being
at right angles to the cylinder axis, whilst at the back of the valve the apertures
are oblique in a converging direction.
The cut-off valve is of a tapering or doubly-inclined form, and is able to traverse
or reciprocate upon the distribution valve in a direction at right angles to the motion
of the latter. The steam pressure (or it may be a spring) at the inner end of the
cut-off valve spindle, tends to move the cut-off valve in one direction; in the reverse
direction, it is operated from the governor spindle by a frustum of a cone, which
rotates in contact with an antifriction roller carried by the valve spindle. The cone

page_text: is able to move endwise along the governor spindle, but by a key and groove is
compelled to rotate with it.
The governor spindle is parallel to one side of the
cone, and is connected to the governor so as to be operated by it. The governor
spindle is driven by bevil gear from the main shaft.
A is the high-pressure cylinder; B, the low-pressure cylinder; C, the condenser;
D, the air pump; E, E, are the Corliss arms; F, F, the disc cranks; G is the crank
shaft; H, the Hy wheel; I, the separate steam casing surrounding the cylinders,
aud forming a steam jacket; K, the end cover for giving admission to the large and
small cylinder covers L and M respectively; N, the ribs on the sides and ends of
the cylinders as well as on the passages between the cylinders for transmitting beat
from the steam in the jacket to the steam working in the cylinders.
The distribution of the steam is effected as follows:-O is the distribution slide
valve of the high-pressure cylinder driven by the eccentric R fastened on the crank
shaft in the usual manner. P is the expansion valve for regulating the admission
of steam into the high-pressure cylinder during a longer or shorter part of the
piston stroke. It has the vertical motion communicated to it by means of the
vertical spindle R. The upward motion of this spindle is produced by the pressure
of the steam in the jacket, which is only partially balanced by the downward
pressure of the atmosphere on the outside. It is therefore only necessary to com-
inunicate positive downward motion to this spindle in order to impart the necessary
travel to the expansion valve P. This vertical motion is communicated from the
cone T, revolving and sliding on the shaft U, driven through the bevel wheels V
and W by the crank shaft G. The position of the cone T on the shaft U and conse-
quently the travel of the vertical spindle R, are controlled by the governor X, driven
from the same shaft U, which communicates motion to the cone T, and thus through
the antifriction roller S and spindle R to the expansion valve P. The steam being
worked in the ordinary way in the high-pressure cylinder is conveyed through the
passage Y into the steam chest of the low-pressure cylinder, where it is distributed
and exhausted by the low-pressure slide valve Q driven as usual by the eccentric Z
attached to the crank shaft. The air pump D is driven by means of a rocking
shaft (a) and the levers (b) and (c), which receive their motion from the eccen-
tric rod (d) driving the low-pressure slide valve.
Figures 16, 17, and 18, shew a modified arrangement of expansion gear which
may be used in this or other engines, Fig. 16 being a plan partly in section ;
Fig. 17, a longitudinal section; and Fig. 18, a plan in section.
Here the distribution valve A receives a fixed positive motion in the ordinary
way from the valve spindle driven by an eccentric rod, and the cut-off is produced
by the cut-off valve B sliding at an angle on the back of the valve A. The cut-off
valve B is moved by the spindle C. This spindle receives its motion from the
cylinder E placed on the shaft D so as to act similarly to a cone, by which means it
is capable of imparting motion varying from zero to full stroke to the spindle C.
The position of the cylinder E is determined by the governor on the governor
spindle driven by bevel wheels from the crank shaft in the usual way.
Figures 19, 20, 21, and 22 shew a modification of the engine last above described.
Here, the overhanging cylinders are carried on a flange at the end of the bed
plate, and are surrounded by a steam case or jacket, the cylinders being provided as
before with heat ribs for conveying heat from the steam in the case to the steam
working inside the cylinders. The valve for the high-pressure cylinder is of the
form herein-before described with reference to Figs. 10 and 11. This valve receives
a positive alternating movement by means of the valve spindle and eccentric from
the crank shaft, and the reciprocating motion to produce the varying expansion is
produced by means of the spindle which is moved by the cylinder revolving with
the governor shaft, the position of such cylinder being determined directly by the
governor in the way before described. The cylinder Y here acts similarly to the
cone Y in Fig. 3.
A is the high-pressure cylinder; B, the low-pressure cylinder; C, the valve of
the high-pressure cylinder; D, the valve of the low-pressure cylinder; E, the steam

page_text: jacket; F, F, are the heat ribs; G is the bed plate; H, H, are the Corliss arms;
I, I, the disc cranks; K is the fly wheel; L, the crank shaft; M is the condensor.
Having described the nature of my said Invention, and explained the manner of
carrying the same into practical effect, I would have it understood that what I
consider to be novel and original, and therefore claim as secured to me under the
herein-before in part recited Letters Patent is,-
1. Providing the piston of a compound engino of the class herein-before referred
to with an extension, and the cylinder cover with a cavity or case having an air
valve opening outward, the whole arranged so as to establish an approximate
vacuum as the piston extension is withdrawn from the cavity or case, substantially
as described.
2. Providing the cylinder cover of a compound engine of the class herein-before
referred to with a displacement piece furnished with an air valve opening outward,
and arranging an annular extension of the piston to work in the annular spaco
between the cylinder and the displacement piece, substantially as described.
3. The arranging automatic expansion gear to effect and regulate the cut-off, by
the connection to the governor with a valve arranged to move in a direction at an
angle to the distributing movement imparted from the eccentric, substantially as
herein-before described.
4. The constructing and arranging steam engines substantially as herein-before
described with reference respectively to Figs. 3 and 4, to Figs. 5 and 6, to Figs. 12,
13, 14, and 15, and to Figs. 19, 20, 21, and 22 of the accompanying Drawings.
In witness whereof, I, the said Druitt Halpin, have hereunto set my hand
and seal, this Third day of March, in the year of our Lord One thousand
eight hundred and seventy-nine.