Improvements in Cynder-and-pi
Year: 1889

page_text: Improvements in Cynder-and-pi
I, OLIVER IMRAY, of No. 28 Southampton Buildings, Chancery Lane, in the County
of Middlesex, Fellow of the Institute of Patent Agents, 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 an improved construction of cylinder-and-piston motor-
engines wherein the distribution of the motor fluid is effected directly, that is to
say without the use of distributing devices such as are ordinarily used.
For this purpose the hollow space of the piston is in continuous communication
with the steam supply pipe. The steam passes from the hollow piston alternately
into the front or rear chambers of the cylinder.
The hollow space of these working pistons serves therefore in substitution of the
slide valve box, and the outer surface of the piston in substitution of the slide valve
faces of ordinary distributing valve motions.
In the several constructions hereinafter described with reference to the accom-
panying drawings, corresponding parts are marked with the same letters of reference.
A is the cylinder and B the piston.
Construction I (Figs. 1 to 4) shews a double acting piston valve motion with
automatically acting inlet valves.
Construction II (Figs. 5 to 8) shews a double acting piston valve motion with
reversing gear.
Construction III (Figs. 9 to 12) shews a double acting piston valve motion with
automatically acting inlet valves.
Construction IV (Figs. 13 to 15) shows a double acting piston valve motion with
automatically acting inlet and outlet piston slides.

page_text: Construction V (Figs. 16 and 17) shews a double acting steam engine with slides
or valves regulated by steam and arranged for any given degree of filling.
Referring to Construction I (Figs. I to 4) with double acting piston valve motion
with automatically acting inlet valves:
Fig. 1 shews a longitudinal section of the cylinder, Fig. 2 a section at C-D
of Fig. 1, Fig. 3 a section at A-B of Fig. 1, and Fig. 4 a section at E F of Fig. 1.
The working of this construction of a piston valve motion as far as it is already
known is as follows:
The steam flows through the supply pipe a and the passage 6 arrangod in the
cylinder wall, into the hollow piston B and passes, as indicated by arrows, behind
the piston, driving the same forward. The steam which, at the right hand, is in front
of the piston escapes through the port d and d arranged in the cylinder wall into
the passage and from thence into the exhaust pipe g. When the piston has
arrived at the right hand end, the steam passes in the same manner to the front
surface of the piston and drives the latter back. The steam which has performed
work behind the piston escapes through the ports to the exhaust pipo g.
The present improvement consists of the arrangement, in the already known valve
motions, of two steam inlet devices, one for the forward and the other for the
backward stroke of the piston B. These inlet devices are regulated by the motor
piston which operates as heretofore.
The steam exhaust ports d d are also arranged in the same manner as
hitherto in uso. The valves i, arranged in the dome of the cylinder and firmly
connected to a small spring piston h, have for their purpose to obtain an exact
degree of filling, whilst the lead and the discharge of the steam are regulated_by
the piston. The working of these new arrangements is as follows:-The piston B is
shewn in its dead point position (at the left hand). The steam arriving from the boiler
passes through the tubulur piece a and the passage b, arranged in the cylinder wall,
into the hollow space of the piston B, which is completely relieved of strain.
When the piston moves to the left hand and the edge 2 of the passage of the piston
passes beyond the edge 1 of the passage m (Fig. 1) steam is admitted to the space
above the valve, but this steam is in the first instance without any effect, as the valve
cannot be raised, the pressure between piston h and valve i being compensated, so that
the.steam inlet appliances are completoly relieved of strain. But the effect is different
when the piston has arrived at the end of its stroke; the steam issuing from the
hollow space of the piston B acts from below on the valve, which is consequently
lifted and only closes after the piston B has moved to the right hand and the edge 2
of the channel of the piston has passed over the edge 1 of the passage m of the
cylinder; the steam begins now to expand and it escapes when the piston B passes
over the exhaust passages d' and d (see Fig. 3). The action is the same when the
piston moves from the right hand to the left.
The exact extent of filling when the piston arrives at the end of its stroke is
therefore to be measured by the distance from the edge 2 of the passage of the piston
to the edge 1 of the cylinder.
The details of the construction of the valve may be varied for effecting the purpose
of this arrangement, viz., to reduce the lead at the admission of steam in single and
double acting piston valve motions; the construction I may be used in single or
double cylinder machines as well as in compound machines.
Construction II (Figs. 5 to 8) Double acting piston valve motion with reversing gear.
Fig. 5 shews a vertical section through the casing of the cock. Fig. 6 is a section
at A-B of Fig. 5, Fig. 7 a top view of Fig. 5 and Fig. 8 a section at C-D
of Fig. 5.
The piston B is constructed in the same manner as above described, and the steam
cylinder A with the inlet and exhaust passages is identical with the previously
described construction. The cylinder and piston are not completely shown in the
drawing as otherwise it would be necessary to repeat what has been said already about
them. It is only necessary to observe that when the piston B moves from the left
end to the right end, the discharge of the steam takes place when the edge 3 of the

page_text: piston passes over the edge 4 of the channel d" and during the pistons stroke from
the right end to the left, when the edge 3' of the piston passes over the edge 4' of the
passage d¹¹
The reversing gear consists essentially of the cast iron cock casing L having tightly
ground in it the plug R which is divided by a central partition w into two chambers;
through the upper chamber K passes the steam which has performed work while fresh
steam flows through the lower chamber J.
The section of Fig. 8 corresponds to that of Fig. 6 the middle axes a x and y y
covering each other. The space J is continuously filled with fresh steam.
In the position of the cock plug R shewn in the drawing fresh steam arriving from
the boiler cannot pass into the cylinder, as the passages 5 and 6 do not communicate
with the passages o" and o; in the position shewn in Fig. 6 the steam which has
performed work escapes through the passages 11 pp and it flows through K into
the discharge pipe g and from this into the open air or into the condenser.
111
When the piston B, being in any position, is to be inmoved from the left hand to the
right, the plug R is turned in such a manner, that the surface 4 covers the passage p";
fresh steam is then admitted through port 5 and the passages o" and o behind the
piston when the piston has begun its motion the plug of the cock is turned back
again into its first position.
When the piston B, being again in any position, is to be moved from the right hand
to the left, the plug R of the cock is turned so far to the right hand that the face 4
covers the passage pand in this case fresh steam flows through opening 6 and
passages and behind the piston; when the piston is in motion the plug of the
cock is turned back again, as previously described, into its first position; the steam
which has performed work then escapes in the same manner as hereinbefore described.
If the engine be in motion or running at full speed, then by the described
operations, i.e. by turning the plug of the cock according as the engine is to run to
the right or left, a reversing will always be effected.
This construction of the cock for reversing may also be replaced by a valve or
slide construction.
Construction III (Figs. 9 to 12) Double acting piston valve motion with auto-
matically acting inlet valves.
Fig. 9 shews a longitudinal section of the machine.
Fig. 10 a horizontal section at A B Fig. 9.
Fig. 11 a vertical section at CD Fig. 9.
Fig. 12 a top view of the valve box.
This construction is identical with the arrangement described and shewn in Figs. 1 to 4
except that in place of valves, piston slides are used which are entirely relieved of strain.
The working of this construction is as follows:
:-
The steam arriving from the boiler passes through a and b into the piston which is
in equilibrio. When the piston moves to the right hand, and the edge 21 of the
piston arrives at the edge 11' of the passage of the cylinder, or when, on the further
motion of the piston B to the right hand, the passage m¹ is opened, fresh steam
flows through the passages m' m' and surrounds the piston slide h', the passages m' m²
are however still covered by the piston slide .
On the continued motion of the piston B to the right hand and shortly before it has
arrived at the end of its stroke, the advance admission of steam takes place as the
edge 21 of the piston passes over the edge 1 of the cylinder.
Steam now flows from the piston B through the passage to the annular surface of
the piston slide and drives the intter so far as to uncover the passage m².
For producing this motion of the piston slide, the outer end thereof and of the slide
casing is made of a slightly less diameter than that of the inner end of the slide and
casing so as to afford an excess of area on the inner annular surface. During the stroke
of the piston to the left hand fresh steam is admitted behind the piston until the
edge 2 of the piston B passes over the edge 11' of the passage m' of the cylinder.
The action is the same when the piston moves from the right hand to the left.
The piston slide 4' is moved back into its first position by the spiral spring. The

page_text: The steam escapes in this construction in the same manner as in the constructions
above described, through the passages d and d¹.
Construction IV (Figs. 13 to 15) Double acting piston valve motion with
automatically acting inlet and outlet piston slides.
Fig. 13 shows a longitudinal section of the engine.
Fig. 14 a horizontal section at A-B Fig. 13.
Fig. 15 a vertical section at CD of Fig. 13.
This construction differs from the preceding one in first place in that, for automati-
cally regulating the inlet and outlet of steam, but one piston slide is necessary, and
secondly, that this construction is particularly suitable for being used as a compound-
engine.
It furthermore offers the advantage, that notwithstanding the automatic distribution
of the motor fluid by the piston slide, a forward and backward motion can take place
here in the same manner as in the constructions above described.
The action of this construction is as follows:-
:-
In this construction the piston B is as before represented at the end of its stroke
at the left hand.
In this position of the piston B the piston slide h h is driven by the steam arriving
from the hollow space of the piston B to the right hand, (owing to the differential area
as in Fig. 9) thus opening the passage m closing the exhaust passage funcovering
the other exhaust passage and closing the second inlet passage m for the stroke of
the piston B to the left end.
When the piston now begins its stroke to the right hand, steam will be admitted
until the edge 2 of the piston passes over the edge 11 of the passage m. On the front
side of the piston the steam escapes until the edges 5 of the piston passes over the
exhaust passage f, and then begins the compression.
and acts
The discharge of the steam on this side of the piston takes place through the
passages fand and through the exhaust pipe g.
When the piston has arrived at the end of its stroke to the right
hand, the steam flows from the piston through the passage 21
on the annular surface of the piston slide h, driving the latter to
the left hand, whereby the inlet passage m³ is uncovered and steam again admitted
until the edge 21 of the channel of the piston passes over the edge 111 of the passage m²,
when the piston moves to the left hand.
To the piston slide are connected by the rods cand e the small buffer pistons d
and d, which have for their purpose to reduce the shock of the piston when the piston
slide is thrown by the steam acting on it from one side to the other.
Construction V (Figs. 16 and 17) Double acting steam engine with slides or valves
regulated by steam and arranged for any degree of cut off.
Fig. 16 shews a longitudinal section of the steam cylinder.
Fig. 17 a cross section at A-B of Fig. 16.
The construction of this engine is particularly characterised by the regulation of
the inlet and outlet slides (in place of slides, valves may also be employed) which is
effected solely by steam, without using any moving mechanism, and this for any degree
of filling, as it has already been said in the beginning of this specification.
The steam piston is a spring piston, a so-called double piston, having a hollow space
or chamber o and a hollow piston rod p into which flows continuously steam for filling
the space o.
There are arranged 2 inlet and 2 outlet slides, the latter being connected
with each other by a rod so as to form a whole. By this construction is obtained what
is absolutely necessary for a well constructed valve and precision engine, that is to say
to have separate inlet and separate exhaust passages.
The action of this construction is as follows:-
As in all the other constructions, the steam piston in the cylinder A is here also
shown at the end of its stroke or in its dead contre position at the left hand side; the
piston B will therefore move to the right hand, as is marked by the arrow.

page_text: The direct steam arriving from the boiler flows through the pipe aa a into the small
slide chests 6 and 6' arranged at the two ends of the steam cylinder, but at the same
time the steam passes through the pipe into the pipes and in consequence also into
the hollow piston rod p and the space o arranged between the two double
pistons B.
The steam therefore passes through the left passage c into the cylinder; the right
passage c' is shut, the left outlet slide has closed the exhaust passage 9 and the right
outlet slide has opened the same.
Assuming the so-called double-piston B to have begun its stroke to the right
hand; shortly before it has arrived at the end of its stroke the following will take
place.
When the chamber o of the steam piston passes over the small perforation 1
arranged in the right hand end of the cylinder, fresh steam flows from the space o
through the perforation and pipe 1 behind the small piston d driving the latter to
the left hand and thus causing the slide to close the exhaust passage in the right
hand end of the cylinder, and the slide to open the exhaust passage g in the left hand end
of the cylinder. The steam which has acteil on the piston B during its stroke to the
right hand may pass through the passage c² 6 and g into the open air or into the
condenser, according as the perforation I is made or arranged, a more or less high
and constant degree of compression may be obtained.
The stop has for its purpose to limit the stroke of the outlet slides and by
means of the elastic discs fand f¹. When the chamber o of the piston B which is con-
stantly filled with steam, passes over the perforation 2, steam flows through the latter
and through pipe 2 behind the small piston d of the right hand inlet slide driving it
to the left and thus causing the inlet passage c¹ to be opened. According to the
desired degree of cut-off, steam is directed to the piston m' according to the position
of the regulator, by means of a device not shewn in the drawing and the
piston as well as the piston d being rigidly connected with the slide the inlet
passage c will be closed by the slide and the expansion will begin.
The diameters of the pistons m and m' are larger than that of the pistons d and d².
The action will be the same when the piston B moves from the left to the right.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed I declare that what I
claim is :-
1. In motor engines, wherein the distributing valve motion is directly effected by
means of the inotor piston, the arrangement of two steam inlet devices in such a manner
that the steam flows from the hollow piston B through the passage formed in the
cylinder wall to behind the piston's surface, and at the same time also through a
valve connected to the piston h and arranged in a special casing, this valve, which is
regulated by the piston B itself, being opened shortly before the piston B has arrived
at the end of its stroke, substantially as herein set forth and shewn in Figs. 1 to 4
of the accompanying drawings.
2. In motor engines wherein the distributing valve motion is effected directly by
the motor piston, the arrangement of a reversing device consisting of the cock casing L
and the plug R ground therein, the upper chamber K of which, communicating with
the exhaust pipe 9 may be put in communication with the outlet passages d³ ³pp¹ p³ p³
of the steam cylinder and the lower chamber J communicating with the steam boiler, may
be connected to the inlet passages o o¹ o o³ of the cylinder in such a manner that,
by turning the cock plug R the fresh steam may be directed to the one or the other
side of the piston, substantially as herein described and shewn in Figs. 5 to 8 of the
accompanying drawings.
3. The modification of the construction referred to in claim 1 consisting in the
substitution for the valves i of piston slides h h relieved of strain and arranged in
special chests and combined, with the passages i, m im¹ substantially as herein set
forth and shewn in Figs. 9 to 12 of the accompanying drawings.
4. The modification of the construction referred to in claim 3, consisting of the

page_text: connection of the two piston slides to a doube slide h h in combination with the
passages i, m, i, m² in such a manner that shortly before the piston B has arrived at
the end of its stroke, the steam enters the passage m or m' driving the piston slide h h to
the one or the other side, so that the steam flows behind the piston not only through
the recesses arranged in the cylinder wall but also through the passages m, m², i
substantially as herein set forth and shown in Figs. 18 to 15 of the accompanying
drawings.
5. A distributing valve mechanism for motor engines wherein the inlet and outlet
valve (slides) are regulated solely by steam pressure without any special mechanism.
such valve mechanism being characterised by tho arrangement of the piston B having
a hollow space o which is in continuous communication through the hollow piston rod p
with the steam supply pipe, in combination with the inlet slides i and actuated by
the pistons d¹ and m or d and m² and with the outlet slides and 3 connected to each
other and actuated by the pistons and d³, the pistons d, d' d' d³ being put in motion by
the steam arriving from the hollow space o through the perforations 1, 2, 11, 22,
substantially as herein described and shewn in the figures 16 and 17 of the accompanying
drawings.