IMPROVEMENTS IN STEAM ENGINES
Year: 1852

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex, and
of Glasgow, North Britain, Gentleman, send greeting.
-
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Sixth day of July, in
the sixteenth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said John Henry Johnson, Her especial license,
full power, sole privilege and authority, that I, the said John Henry Johnson,
my- exors, admors, and assigns, and such others as I, the said John Henry
Johnson, my exors, admors, or assigns, should at any time agree with, and no
others, from time to time and at all times during the term of years therein
mentioned, should and lawfully might make, use, exercise, and vend, within
England, Wales, and the Town of Berwick-upon-Tweed, in the Islands of Jersey,
Guernsey; Alderney, Sark, and Man, and in all Her Majesty's Colonies and
Plantations abroad, an Invention of "IMPROVEMENTS IN STEAM ENGINES," being
a.communication from a foreigner resident abroad; in which said Letters
Patent is contained a proviso requiring that I, the said John Henry Johnson, by
an instrument in writing under my hand and seal, shall particularly describe and
ascertain the nature of the said Invention, and in what manner the same is to be
performed, and shall-cause the same to be enrolled in Her said Majesty's High
Court of Chancery within six calendar months next and immediately after the
date of the said in part recited Letters Patent.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
John Henry Johnson, do hereby declare the nature of the Invention, and in
what manner the same is to be performed, to be particularly described and
ascertained in and by this present instrument in writing as follows, reference
being had to the accompanying Drawings, and to the letters and figures
marked thereon, that is to say:-
The said Invention relates to various arrangements of machinery, apparatus,
or means to be employed for the more economical and effective working of
steam as a motive power, by carrying out the principle of the expansive action
of vapour to a very great extent, by the combination of several steam cylinders
to work in concert together, one cylinder of the series being smaller than the
rest, whilst its piston moves at a higher velocity than that of the other pistons,
the waste steam of the quick working cylinder being supplied to the other
cylinders.
And in order that the said Invention may be readily understood, I shall now
proceed to describe the several Figures on the Sheets of Drawings. hereunto
attached.
Figure 1, on Sheet 1 of the Drawings, is a front elevation of a three cylinder
steam engine, arranged according to these improvements. Figure 2 is a
vertical, sectional elevation of the engine, at right angles to Figure 1. Figure 3,
on Sheet 2, is a plan of the same, and Figure 4, on the same Sheet, is a hori-
zontal section through the cylinders, valves, and steam ports, and other details
corresponding. All the three cylinders are placed upright on the same base
line, as well as in a straight line horizontally, the small cylinder A, into which
the steam is first admitted, being placed between the other two larger cylinders,
these latter cylinders being entirely worked by the steam originally supplied to
the small cylinder. The vertical pipe G supplies the steam at the required
high pressure to the valve chest F, whence it is admitted to the small cylinder
A through the slide valve E, for the first actuation of the small piston B.
After the termination of each stroke of the small piston, the,employed steam
passes off into the two cylinders C, C₁, alternately, and actuates their pistons,
which I shall name D, D', and which have the same length of stroke, but
move with only half the velocity of the small piston; therefore, by the time
the piston B has effected a full stroke, the pistons D and D¹ will only have
accomplished a half stroke, and as the steam from the small cylinder, at its
original pressure, will only occupy. half the capacity of each of the large
cylinders, their, pistons will be impelled the remainder of the stroke merely by
the power of expansion. While the large piston D completes its traverse, the
second one D' (which is so arranged as to be nearly at the end of its stroke
..

page_text: when the other is at the middle) commences to receive the steam of the second
stroke of the piston B, and arrives at the middle of its stroke, while the small
piston B, moving at double the speed, arrives at one end of its cylinder. The
valves must therefore be so arranged as to allow of the proper distribution of
steam to both cylinders from the small one. This may be effected, either by
the arrangement which I have shewn in Figures 1 and 2, or by the means
shewn in detail in Figures 5, 6, and 7, on Sheet 2. Figure 5 is a longitudinal
section of the duplex slide valve and ports. Figure 6 is a plan of the valve
face, and Figure 7 is an end view of the slide valve detached. By the first
arrangement, the slide E, Figure 2; is enclosed in the ordinary steam chest F,
in communication with the boiler through the steam pipe G, which may be
fitted with an ordinary throttle valve if requisite, and actuated by the governor.
According as the slide is up or down, the steam will be admitted into the upper
or lower portion of the cylinder through the ports a, a', the slide itself being
worked by an eccentric E' on the main shaft, which eccentric may be set
slightly in advance if requisite, to allow the steam to enter slightly before the
completion of each stroke, and cut off the steam at two-thirds, three-fourths,
or four-fifths, as may be found expedient. Two pipes, I and I', communicate
with the escape port b, and branching off from each side of the small cylinder,
they terminate in the two chests J and J' of the large cylinders. These chests
are each fitted with a slide K and K', actuated by eccentrics on the respective
shafts H and H, and these slides are so arranged that when one (the slide K,
for example) opens the top port of the large cylinder C, the other one K¹ closes
the corresponding port of the cylinder C', the opposite effect being produced
at the succeeding stroke of the small piston B. The large cylinder C' now
receives the steam from the small one, as the communication has been reopened
with the pipe I, and remains so as long as the passage between the pipe I and
cylinder C remains closed. By the mode shewn in Figures 5, 6, and 7, the
slide of the small cylinder is so arranged as always to close one of the two
passages d and d', and open the other, thereby directly closing the passage
between the small cylinder A and one of the large ones, and allowing the
escape steam to enter the other large one. By this means one of the openings
will be certain to be closed on one side, and opened on the other, before the
passage of the steam into the pipes I or 1'. A larger steam chest and valve
face is required in this system than in the other, requiring more power to
actuate the slide, if the pressure of steam were not equally balanced on both
sides of the valve, but the slide may be made to bear on two surfaces, viz', the
face of the cylinder, and the interior of the chest, as shewn in 'the section,
Figure 5. The steam which is thus distributed, first to one large cylinder, and

page_text: then to the other, may enter either one common condenser L (Figure 2), fitted
with one air pump M, or two distinct condensers may be used, each having one
air pump of its own. The power is communicated from three cylinders, by
the rods M, M', and M2; and the respective connecting rods N, N'; and N²,
guided vertically by the cross heads O: These connecting rods are attached to
the cranks P, P', 'and P2, the first being carried by the main shaft H; which
receives the 'movement of the two shafts H and Hby i means of the spur
wheels andQ, both gearing into the smaller wheel R; of one-half their
diameter, or as 1 to 2 By this gearing the fly wheel, as ordinarily used, may
be much diminished both in weight and diameter, owing to the very favorable
action of the combined cranks and gearing. If a condensing engine is re
quired, either two air pumps may be used, or one only, which may be double
or single acting.And either one or two feed pumps may be employed simul-
taneously or alternately, as desired: If one air pump is used, it may be placed
directly under the main shaft H, and actuated by a small crank "m, on the
intermediate shaft 'n receiving motion through the spur wheel O. If two air
pumps are used, they may be worked by cranks P and P on the shafts H
and H', the feed pump being worked by eccentrics on the same shaft. Or one
of these cranks may work the air pumps, and the other the feed pump. Indeed
these cranks may be used whereby the feed pumps, like the air pumps, may
be always worked from the main shaft, as first described. The framework">is
of great simplicity, consisting merely of two cast-iron columns S, bolted to 'the
bed plate T; which supports the three cylinders. The columns may be united
by a cast-iron entablature U, having its two extremities let into the walls of
the engine house. It may be further strengthened by curved brackets U₁
bolted to the columns and entablature, which rests on two cross beams X
placed on each side of the fly wheel Y, and let into the walls which divide the
engine house from the workshop. If requisite, four columns may be used to
support the entablature, and smaller ones K may be secured to them, serving
at the same time as guides for the slides O. The small columns may be
bolted at their lower ends to the upper flanges of the cylinder, and 'united by
an entablature at the top. It is of course not absolutely necessary that all
three cylinders should be. of the same length, as by suitably adjusting the
wheelwork above, the same result may be obtained. "Figures' 8 and 9, on
Sheet 3 of the Drawings, respectively represent an elevation and vertical
section of a three cylinder engine on this principle, the small cylinder being
fitted with an expansion valve. By making the stroke of the piston of the
cylinder A less than that, of the two other cylinders, two advantages are gained,
viz', the reduction of the rapidity of its movement, and the lowering of the

page_text: centre of the main shaft H, as by this arrangement it will be lower instead of
higher than the shafts H H By using a spur wheel of double the diameter,
the small piston may be made to travel at the same rate as the large ones.
But this latter mode of construction will evidently not be so advantageous, as it
approaches nearer to the ordinary arrangement of double cylinder engines!
The two shafts H and H, being the highest, are placed on the entablature Û³,
parallel with the entablature U, and attached to it by the small pillars U. The
upper entablature may be extended and fitted into the walls of the engine
house, and further secured to the columns S by the bracket U'The small
cylinders may be surrounded by a steam jacket, which may receive the steam
direct from the boiler, to be afterwards passed into the large cylinders: The
steam may be distributed, either by the ordinary' slide, as described "above, or
by slides of the two openings, and an expansion valve, either of the construc-
tion shewn in Figure 9, or any other suitable arrangement may be used. In
place of using round columns for guiding the cross heads, pillars, with their
faces planed on purpose to receive the brasses or slides of the cross 'heads O,
may be adopted. The slides are each fitted with a piece of india-rubber,
which, on their descent, dips into a reservoir of oil, and effectually lubricates
the guide as it ascends: These guides are secured to the flanges of the cylinders
by screw rods and bolts, which pass through their entire lengths, and secure
'them to the entablature Z, connected with the columns S. The height of the
engine may be much reduced by sinking the larger cylinders into the bed plate,
as shewn in Figure 10, on Sheet 4 of the Drawings, thereby allowing the
'three shafts, with their bearings, to rest on the same entablature in one 'hori-
zontal line, yet, nevertheless, obviating the necessity of very large spur wheels,
or of having the columns far apart.
As it is evident that various arrangements may be made without deviating
from the main features of this Invention; some additional "arrangements are
delineated on Sheet 4, as applicable to 'marine engines and other "purposes.
Figures 11, 12, and 13, on Sheet 4, 'represent an elevation, plan, and trans-
verse section of a horizontal three cylinder engine; the small cylinder A being
slightly raised above the two others C and C¹. The main shaft H receives its
movement partly from the small cylinder A, the connecting rod of which is
attached to a stud in the wheel R, on the extremity of the main shaft, and
partly from the larger spur wheel Q, which is keyed on to the middle of the
shaft H', and worked from the large cylinders by the two cranks M and M',
fixed at each extremity of the shaft. By this arrangement it is evident that a
very powerful engine may be built in a very small space, all the ports being

page_text: under the command and reach of the engineer. The air end feed pumps may
be worked in any convenient manner, either vertically or otherwise. Figure 14
is a stationary 'oscillating engine. The steam is admitted by one trunnion of
the small cylinder, and escapes by the opposite trunnion, either to the right or
left, into the trunnions of the large cylinders C and C', by the pipes t, t¹; as by
this modification the pistons may be attached directly to the crank pins, the
height of the engine will be greatly reduced as compared with that of an engine
with fixed cylinders. Figures 15 and 16 represent a front and side view of an
engine of three cylinders, particularly adapted to paddle steam boats. The
peculiarity of this arrangement is, that while the small cylinder A is fixed, the two
large ones C and C' are oscillating. The motion of the small piston is in this
case transmitted to the shafts H' and Hs by the pinion R, which serves as a
crank fitted on to the extremity of the shaft H, and into the spur wheel Q, with
which the pinion R gears. The air pump may be placed opposite to the small
cylinder, in order that it may receive its movement from the spur wheel Q, by
another pinion for that purpose, as herein shewn.
Finally, Figure 17 represents an oscillating engine, adapted for screw pro-
pellers, the large cylinders being placed at an angle.
Having now described and particularly ascertained the nature of this Inven-
tion, I may observe in conclusion, that I do not confine or restrict myself to
the precise details or arrangements which I have had occasion to describe or
refer to, as many variations may be made therefrom, without deviating from
the principles or main features of the Invention; but what I consider to be
novel and original, and therefore claim as the Invention secured to me by the
herein-before recited Letters Patent, is,-
First, the general arrangement and construction of steam engines, herein-
before described.
Second, the application and use in steam engines of a small steam cylinder,
combined with two or more larger cylinders, in such manner, that whilst the
first motion shaft of the small cylinder revolves at twice the rate of the shafts
of the larger cylinders, the latter cylinders are at the same time worked by the
escape steam from the first or small cylinder.
Third, the system or mode of constructing steam engines, wherein the escape
steam from one cylinder is alternately or successively discharged into two or
more additional cylinders.
Fourth, the system or mode of constructing steam engines by a differential
or alternate expansive discharge from one cylinder into two or more larger
cylinders, as herein-before described.

page_text: Fifth, the system or mode of constructing steam engines with one fix
cylinder, and two or more oscillating cylinders combined.
In witness whereof, I have hereunto set my hand and seal, the Twent
first day of December, in the year of our Lord One thousand eig
hundred and fifty-two.
AND BE IT REMEMBERED, that on the Twenty-first day of December, in
the year of our Lord 1852, the aforesaid John Henry Johnson came before
our said Lady the Queen in Her Chancery, and acknowledged the Speci-
fication aforesaid, and all and every thing therein contained and specified, in
form above written. And also the Specification aforesaid was stamped according
to the tenor of the Statute made for that purpose.
Enrolled the Twenty-third day of December, in the year of our Lord
One thousand eight hundred and fifty-two.