Improvements in Double Acting Atmospheric Steam-engines.
Year: 1890

page_text: Date of Application. 27th Oct., 1890
Complete Specification Left, 27th Jan., 1891-Accepted, 2nd May, 1891
PROVISIONAL SPECIFICATION.
Improvements in Double Acting Atmospheric Steam-engines.
A. communication to me from abroad by IWAN KENTNOWSKI, of Sohrau, in the
Empire of Germany, Officer of the Exchequer.
1, EDMUND EDWARDS, of the firm of Edwards and Co., Patent Agents and
Engineers, of 35, Southampton Buildings, Chancery Lane, in the County of
Middlesex, do hereby declare the nature of this invention to be as follows: --
The present invention consists of an engine having a cylinder in which three
pistons work, the central piston working with high pressure steam cut off at any
part of the stroke whilst the two outer pistons work by atmospheric pressure,
upon the outer sides, their inner sides being connected with a condenser.
The steam cylinder which is open at both ends, is divided into three parts by
means of two transverse diaphragms. In the three parts so formed three pistons
fixed upon a common piston rod are moved back ward and forward. The piston rod
actuates by means of a connecting rod the crank shaft of the engine, which by
means of berilled toothed wheels drives a shaft parallel with the cylinder which
actuates the valves.
Upon this shaft two excentrics are mounted one behind the other by means of
which two upper and two lower cylindrical slide valves are turned for distributing
the steam. The slide valves are fitted into two corresponding cylindrical chambers
parallel with the cylinder which are closed at the ends, and which are arranged
respectively above and below the cylinder. The upper valve chamber is divided
into three parts by means of prolongations of the diaphragms of the main cylinder
whilst the lower valve chamber is only divided into two parts by a central partition.
The upper and lower slide valves which are fixed upon two shafts are actuated by
excentrics which drive racks gearing with pinions mounted upon the respective
valve shafts. At the beginning of the outward stroke the steam entering through
the inlet pipe into the centre of the upper valve chamber, is led through the upper
back valve and a port in the cylinder behind the middle piston and drives the latter
forward whilst the upper forward and the lower back valves shut respective ports
in the middle partition of the cylinder whilst by the lower forward valve the middle
part is connected with the front part of the main cylinder. The engine drives at
the same time the excentrics in the proper direction.
If now one of the excentrics causes by means of the rack and pinion the port of
the upper back valve to close the steam is cut off from behind the central piston.
This is done before the said piston has finished its stroke so that the steam then
works expansively the other excentric allowing the lower forward valve to remain
in its position.
During the first stroke after the starting of the engine no further effect is
exercised by the steam.
Suppose however the outstroke described is the second one then the steam
expanded in front of the piston would pass behind the piston in the front division
of the cylinder, when the middle piston is driven forward. At the same time the
front division of the cylinder is connected behind its piston with a condenser which
condenses the expanded steam, which is reduced to a very low pressure. This
connection is effected by means of the upper valve and a pipe from the upper
chamber to the condenser, and by the valve and another pipe from the lower
chamber to the condenser. When the central piston has reached the end of its
stroke the excentrics have taken a position so that the upper back valve and the
lower forward valve close the ports whilst the upper forward valve admits the
steam in front of the middle piston at the same time that the lower back valve

page_text: admits the expanded and utilized steam in front of the piston in the back division
of the cylinder, suitable pipes connecting simultaneously the back division of the
cylinder with the condensers.
The steam acts now upon the centre backward moving piston whilst at the same
time in the same direction the external atmospheric pressure presses with a certain
force the front piston back into the front division of the cylinder in which a vacuum
has been formed by the condenser.
After the central piston has reached a certain point of its backward stroke, the
steam is cut off, as already described and expansion in the middle division of the
cylinder begins until the piston has arrived at the end of its stroke. The reversal
of the distributing valves is then effected, the middle piston is again driven
forward with full steam pressure whilst now the back piston is propelled by the
atmospheric pressure.
The same series of movements is repeated. The excentrics are each provided
with an excentric sheave consisting of a smaller and of a larger semi-circle and
with a strap with two forked pairs of arms which are directed inward and slide on
the excentric sheave. The excentric for the steam admission and for the cutting
off the steam is morcover provided with a moveable lifter, which is mounted upon
the periphery of the excentric sheave and by means of which the cutting off the
steam for the expansion is effected. The expansion begins earlier or later according
to the position of the lifter on the sheave. The revolving valve shaft operates the
governor by means of bevilled wheels. Upon the vertical shaft of the governor
an inclined cylinder with wedge and groove is mounted which follows the up and
down movement of the governor, whereby the position of a throttle valve in the
steam pipe is varied according to the speed of the engine and by means of a
sliding rod which embraces the inclined cylinder, and is connected with the
throttle valve.
The condenser consists of a quadrangular case into which the exhaust steam
from the cylinder is admitted from above, whilst from below the condensing water
is led.
The latter rises and enters through a perforated central tube and also through
perforations in the side walls, in the form of fine spray into the condenser whilst
the hot water escapes through a separate pipe.
Dated this 57th day of Catalan 1900
EDWARDS & Co.,
35, Southampton Buildings, London, Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Double Acting Atmospheric Steam-engines.
A communication to me from abroad by IWAN KENTNOWSKI, of Sohrau, in the
Empire of Germany.
1, EDMUND EDWARDS, of the firm of Edwards and Co., Patent Agents and
Engineers, of 35, Southampton Buildings, Chancery Lane, in the County of
Middlesex, 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 and accompanying drawings, that is to say :-
The present invention consists of an engine having a cylinder in which three
pistons work, the central piston working with high pressure steam cut off at any
desired part of the stroke whilst the two outer pistons work by atmospheric
pressure, upon their outer sides, their inner sides being connected with a condenser.
In the accompanying drawings, which are in illustration of the invention,
Figure is a vertical longitudinal section,
Figure 2 an end view,

page_text: Figure 4a horizontal section, and
Figure 5 a transverse section, of an engine constructed according to the inven-
tion.
Figures 6, 7, 8, 9, and 10, are detailed views of different parts.
The steam cylinder A which is open at both ends is divided into three parts by
means of two transverse diaphragins B. In the three parts so formed, three
pistons fixed upon a common piston rod C are moved backward and forward. The
piston rod actuates by means of a connecting rod F the crank shaft of the engine,
which by means of the bevilled toothed wheels D drives a shaft E parallel with
the cylinder, which actuates the valves.
Upon this shaft E two excentrics G Gare mounted one behind the other
(Figures 3, 5, 6, 7, 9, and 10) by means of which two upper and two lower
cylindrical slide valves are turned for distributing the steam. The slide valves H H
and I are fitted into two corresponding cylindrical chambers K and L, parallel
with the cylinder, which are closed at their ends, and are arranged respectively
above and below the cylinder A. The upper valve chamber K is divided into.
three parts by means of prolongations of the diaphragms B of the main cylinder A,
whilst the lower valve chamber L is only divided into two parts by a central
partition L. The upper and lower slide valves H H and II, which are fixed
upon two shafts, are actuated by excentrics G G which drive racks SS' gearing
with the pinions R R mounted upon the respective valve shafts I and H.
At the beginning of the outward stroke the pistons and valves are supposed to
be in the positions shewn in Figure 4. The steam, entering through the inlet
pipe M into the centre of the upper valve chamber, is led through the upper back
valve H and the port N¹ in the cylinder behind the middle piston and drives the
latter forward, whilst the upper forward and the lower back valves shut respective
ports in the middle partition of the cylinder whilst by the lower forward valve the
middle part is connected with the front part of the main cylinder. The engine
drives at the same time the excentrics G G in the proper direction indicated by the
arrows in Figure 9.
If now the lifter W of the excentric G bears against the lower lifter W
(Figure 10) it causes by means of the rack and pinion R the port N' of the upper
back valve to close, and the steam is cut off from behind the central piston.
This is done before the said piston has finished its stroke, so that the steam then
works expansively the other excentric G allowing the lower forward valve to.
remain in its position.
During the first stroke after the starting of the engine no further effect is
exercised by the steam.
Supposing however that the outstroke described is the second one, then the steam
expanded in front of the piston would pass behind the piston in the front division
of the cylinder when the middle piston is driven forward. At the same time the
front division of the cylinder is connected behind its piston with a condenser, which
condenses the expanded steam, which is reduced to a very low pressure. This
connection is effected by means of the upper valve P and a pipe Q from the upper
chamber to the condenser, and by the lower forward valve and another pipe Q¹
from the lower chamber to the condenser.
When the central piston has reached the end of its stroke the excentrics have
taken a position, as illustrated in Figure 11, so that the upper back valve and the
lower forward valve close the ports N', P' whilst the upper forward valve admits
the steam in front of the middle piston at the same time that the lower back
valve admits the expanded and utilized steam in front of the piston in the back
division of the cylinder, the pipes QQ connecting simultaneously the back division
of the cylinder with the condensers.
The steam acts now upon the centre backward moving piston, whilst at the same
time in the same direction the external atmospheric pressure presses with a certain
force the front piston back into the front division of the cylinder in which a.
vacuum has been formed by the condenser.

page_text: After the central piston has reached a certain point of its backward stroke, the
steam is cut off as already described and expansion in the middle division of the.
cylinder begins until the piston has arrived at the end of its stroke. The reversal
of the distributing valves is then effected, the middle piston is again driven forward
with full steam pressure whilst now the back piston is propelled by atmospheric
pressure. The same series of movements is repeated. The excentrics G Gare
each provided with an excentric sheave consisting of a smaller and of a larger
semi-circle, and with a strap with two forked pairs of arms W which are directed
inward and slide on the excentric sheave. The excentric for the steam admission
and for the cutting off the steam is moreover provided with a moveable, lifter As
which is mounted upon the periphery of the excentric sheave and by means of
which the cutting off the steam for the expansion is effected. The expansion
begins earlier or later according to the position of the lifter on the sheave.
The revolving valve shaft E operates the governor by means of bevilled wheels.
Upon the vertical shaft of the governor an inclined cylinder T with wedge and
groove is mounted, which follows the up and down movement of the governor,
whereby the position of a throttle valve is varied in the steam pipe, according
to the speed of the engine and by means of a sliding rod N which enibraces the
inclined cylinder and is connected with the throttle valve.
The condenser, Figure 8, consists of a quadrangular case into which the exhaust
steam from the cylinder is admitted from above, whilst from below the condensing
water is led. The latter rises and enters through a perforated central tube X and
also through perforations in the side walls Y, in the form of fine spray into the
condenser whilst the hot water escapes through a separate pipe Z.
Having now particularly described and ascertained the nature of the said inven-
tion and the manner in which the same is to be performed, I declare that what I
claim is
1. A steam engine with a steam cylinder which is divided into three parts by
means of two diaphragms and in which work three pistons, of which pistons the
central one is actuated by steam from the boiler and expanded steam pressure
whilst the two exterior pistons are actuated simultaneously by condensation and
atmospheric pressure, the steam being distributed by the valves H H and II con-
tained in the valve chambers K and L which are arranged above and below the
cylinder, and which are connected with the excentrics GG, which regulate the]
admission and cutting off of the engine steam as well as the opening and closing
of the communications between the three parts of the cylinder and the condenser
respectively in such manner that the central piston in the first part of its stroke
receives direct steam pressure the steam after it has been expanded and utilized
going from the central division of the cylinder over to one of the other parts
where it is afterwards condensed, the outside atmosphere at the same time.
exercising a pressure on one of the outer pistons, substantially as described and
shewn.
2. With the arrangement explained in Claim 1, the construction of the excentric G³,
whose exterior strap works with its projections W upon the periphery of the
inner excentric sheave and which actuates the valve 1 by means of the rod S' and
the pinion, R', whilst the otherwise similarly formed excentric is also provided with
a projecting lifter W³ moveable on the excentric sheave, so as to effect the
reversing of the valve H for the purpose of cutting off the steam from the control
of the cylinder, substantially as described and shewn.
Dated this 27th day of Ionury 1801
EDWARDS & Co.,
35, Southampton Buildings, London, Agents for the Applicant.