IMPROVEMENTS IN STEAM ENGINES, AND IMPROVEMENTS IN REGULATING THE POWER AND VELOCITY OF MACHINES FOR COMMUNICATING POWER
Year: 1845

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLES
WILLIAM SIEMENS, of Finsbury Square, in the County of Middlesex, Engineer,
send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her.
Royal Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Twenty-fourth day of December, in the ninth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Charles William Siemens, my exors, adiñors, and assigns, Her especial.
licence, full power, sole privilege and authority, that I, the said Charles
William Siemens, 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 expressed, should and lawfully might make, use, exercise, and.vend,
within England, Wales, and the Town of Berwick-upon-Tweed, my Invention
of "IMPROVEMENTS IN STEAM ENGINES, AND IMPROVEMENTS IN REGULATING THE
POWER AND VELOCITY OF MACHINES FOR COMMUNICATING POWER;" in which said.
Letters Patent is contained a proviso that I, the said Charles William Siemens,
shall cause a particular description of the nature of my said Invention, and in
what manner the same is to be performed, to be inrolled 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, as in and by the
same, reference being thereunto had, will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Charles William Saunders, do hereby declare that the nature of my said

page_text: Invention, and the manner in which the same is to be performed, are fully
described and ascertained in and by the following statement thereof, reference
being had to the Drawings hereunto annexed, and to the figures and letters
marked thereon, that is to say :-
The first part of my improvements in regulating the power and velocity of
machines for communicating power consists in some further improvements in
the Chronometric Governor, a Patent for which was granted to Mr. Joseph
Woods, of Barge Yard Chambers, Bucklersbury, bearing date at Westminster,
the Eighteenth day of April, One thousand eight hundred and forty-four.
Sheet I, Figures 1, 2, and 3, represent my improved chronometric governor,
which I generally apply to steam engines. The differential velocity between
the engine and a revolving pendulum P is obtained by means of three bevil
wheels A, B, and C. The wheel A is firmly connected with the arm or crank F
of the pendulum, by means of the upright shaft (k), and revolves always in concert
with the pendulum. The under wheel (B) is fixed to the pulley D, which is
driven by the engine with its uncertain velocity, and in contrary direction to
the motion of (A). Both these wheels move in gear with the third bevil
wheel (C), which runs perfectly free on its axes, and is also permitted to travel
round the perpendicular socket (d). It is obvious that whenever A and B
revolve in contrary directions, but with equal velocity, C will also revolve on
its axis, but will not change its angular position, while any difference in
velocity between A and B will cause C to follow the direction of the faster
wheel, which will at once alter the supply of steam, the double arm (m) being
attached to the throttle valve T by means of the lever and connecting rod (7).
The pillar N, with its two stops (n, n,) together with the connecting rod i, are
only conveniences to confine the range of the arm (m) according to the range
of the throttle valve T. To maintain the motion of the pendulum a constant
power is required resembling that of a falling weight in an ordinary clock.
This power is given out by the weight W, which tends to pull the wheel C
permanently to one side, and this strain being born equally by the wheels A
and B, causes A, and with it the pendulum P, to revolve, while B, which
revolves in the contrary direction to A, is constantly engaged to lift (W) back
again in its former position.
A further improvement in the chronometric governor consists in a mode of
retaining the arc of vibration of the pendulum within certain limits during the
moments at which a change of load of the engine takes place. In practice,
I have found the power requisite to maintain the action of the pendulum much
less than that required to effect the movement of the valve, and I now adopt
the principle of driving the pendulum with an excess of power, which shall be

page_text: neutralized by a friction apparatus when not wanted, and shall be allowed to
act freely when the governor requires its assistance to move the valve. This I
effect as follows:-R is a ring of cast iron or other proper material, against which
a surface of steel (9) revolving with the pendulum is pressed by its short lever,
5 a spring (s) being placed between the point of the rod and the steel rubber to
let the pressure come on gradually. It is evident that whenever there is an
excess of driving weight, which causes divergence in the arc of vibration, the
surfaces of the steel rubber and of the fixed ring will be pressed in contact
together with a force exactly sufficient to produce the required amount of
friction necessary to counterbalance the excess, and so soon as the pendulum
falls back towards a smaller are of rotation, it will release the friction
apparatus, and permit an increased supply of power to overcome the resistance
of the valve. A second spiral spring (t) is laid in the groove of the arm F,
behind the point of the pendulum, for the purpose never to allow the latter to
drop quite in its perpendicular position, and also to facilitate its starting with
the engine. Another mode of obtaining the differential velocity between the
pendulum and the engine or other machine for communicating power is
represented by Figures 4 and 5, Sheet I.; it consists of a pinion (A), which is
fixed to the upright shaft of the pendulum of an inverted wheel (B), which is
driven by the engine in the contrary direction to the pinion (A) and of a
small pinion (C), which revolves freely on its axis, and is allowed to travel
round the common centre, it being supported from there by the double arms
M, M, from which arms the connection is made to the valve of the engine, &c.
This governor is in all other parts similar to that already described. To move
the gates of water wheels, or the expansion gear or valves of large engines, a
governor of superior power is required. The arrangemenent which I adopt in
such cases is shewn on Sheet II., Figures 1, 2, and 3. It consists of three bevil
wheels, A, B, and C, which are arranged in the same manner as in the governor
first herein describerl, Sheet I., the only difference being that all parts are made
much stronger, and that the wheel B is driven by gear, the motion of the engine
or water wheel being first communicated to the shaft and bevil wheels F. The
most essential difference between this governor and that represented on Sheet I.
consists in its having two pendulums and a friction apparatus of a very powerfull
construction. The two pendulums P and P¹ are suspended from the perpen-
licular spindle K, which spindle may be considered as a continuation of the
haft (4), and therefore transfers the chronom revolutions of the pendulum to
he upper bevil wheel A. The friction apparatus consists of a heavy cast iron
ing L, which is suspended and prevented from turning round by three bolts
a, a, a,) reaching through corresponding holes in the upper bracket (E).

page_text: These bolts admit of the ring L being lifted, but not to drop beyond a certain
limit, when its weight get supported by the heads of the three bolts coming in
contact with the upper surface of the bracket E. Two single cones M and N
are keyed to the upright spindle K, and therefore revolve always with the
proper velocity of the pendulums. The lower cone N is connected with the
two pendulums by means of two short connecting rods (r) and (71), the length
of which can be accurately adjusted by means of right and left handed screws,
and being allowed to slide on its keys it will rise and fall with the balls of the
pendulums. From this it will be understood that whenever the pendulums
revolve in a low are of rotation, the massive ring L will be supported on the
heads of the three bolts; and inasmuch as the two cones are now relieved
from the ring L, all the driving weight is at liberty to overcome the resistances
of the pendulum. The cone N will soon be raised high enough to lift the
massive ring L from its supports, and a considerable amount of friction is
produced between the two conical surfaces. The driving weight, however, is
made large enough to overcome all this resistance; but if, from the shutting
of the valves or gates the driving weight is still more encreased, then the
stationary ring L will be brought in contact with the second cone M, and an
extra amount of friction will be produced, which may be encreased to almost
an unlimited extent. Thus the governor will have power enough to move the
largest gate at the very instant when it is required to do so, for it must be
remembered that the momentum of the pendulum balls themselves are very
powerful agents to commence the action before the friction apparatus can
come into play.
Having now described the nature of this part of my Invention, and the best
mode I am acquainted with in performing the same, I wish to have it under-
stood that I do not claim some of the mechanical arrangements, nor do I
confine myself to the details given. But what I claim is, firstly, the two modes
of obtaining the differential velocity between the revolving pendulum or
pendulums and the machine for communicating power as herein described and
shewn in Plate I.; secondly, the use of a friction apparatus to confine the ar
of revolution of a pendulum or pendulums in a chronometric governor, by
absorbing all surplus amount of driving power, and also to obtain a reserved
power, which will be called into action to overcome the resistances of the
governor, if required.
Another part of my improvements in steam engines, and in regulating th
power and velocity of machines for communicating power, consists in a metho
of distributing or defusing the very unequal resistance of elastic fluids whe
actuated by an air pump more equally over the whole up-and-down stroke
0

page_text: the piston or pistons by condensing and expelling the fluid gradually. Tais
Invention is applicable to all machinery used for exhausting and compressing
elastic fluids, but I shall first describe the nature of my improved apparatus,
which will be a substitute for the air or vacuum pump of condensing steam
engines.
Figure 1, Sheet III., represents my improved air pump.
It consists of the
ordinary air pump cylinder (A) with its piston (P'), and of a second cylinder
(B) of the same length, but only about one third the area of (A). Both
cylinders communicate together through the valve (V), which allows the air
and water to pass from (A) into (B), but not back again. A piston (p)
in cylinder (B) moves in concert with (P), being fixed to the same pump
rod (R), which is moved by the engine; cylinder (B) is provided with a discharge
valve (V) on its lower extremity, and the pipe (C) effects an uninterrupted
communication between the top of this cylinder and the condenser. The play
of this pump is as follows:The air and water which is collected on the top of
the piston (P) is discharged gradually through the valve (V) into the narrow
cylinder (B) during the whole upstroke of the pistons. At the end of the
stroke all air and water has been displaced into the small cylinder, from
whence it is expelled during the downward stroke into the atmosphere. It will
be observed, that during the upstroke of the pistons a part of the resistance
on the large piston will be counteracted by the pressure below the piston
(p), instead of which there will be some resistance during the downward stroke
in discharging the air and water from the smaller cylinder.
Figure 2 represents a double-acting pump on the same principle, which
may be used with equal advantage for exhausting and compressing air. The
large cylinder (A¹) is provided with two inlet valves (a) and (b), and two
outlet valves leading to the small cylinder (B), which are marked (c) and (d);
cylinder B¹ is provided with two outlet valves (e) and (f). The play of this
pump is quite similar to that already described; the air enters either side of
the piston P¹, and is gradually condensed from thence into that part of cylinder
B with which it stands in communication, and from whence it is discharged
into the open air or any suitable reservoir. The long passage (C¹) may be
furnished with two valves (d) and (d'). (d) being intended to prevent the
body of air which is contained within the passage from expanding back again
into the large cylinder at the change of the stroke, and the valve d' is to
prevent its being filled with air of the full density from cylinder B' during the
upstroke of the pistons. It is not absolutely necessary to place the two
cylinders one above the other, but they may also be put side by side and
be worked by two separate piston rods; but I prefer the former arrangement.

page_text: If it is the exclusive duty of an engine to exhaust air, I propose to dispense
with the crank and a separate steam cylinder altogether, and adopt the arrange-
ment as represented by Figures 3, 4, and 5, Sheet III., which is particularly
adapted for exhausting the air from the traction tube of atmospheric railways.
It consists of two cylinders, A and B, of equal length but very different
diameters, A having in this instance three times the area of B. The tube Cis
a continuation of the traction tube of the railway, which terminates in the
upper end of cylinder A. The bottom of cylinder A also communicates
occasionally with the traction tube C, through the inlet valve D. The pistons
P and p are fixed to the common piston rod R, which rod is made very strong
and is loaded also with a heavy mass E, E, and the top of the piston (p), and
by the adjusting weights (W). The air is discharged from B into the atmo-
sphere through the conical valve V, which is lifted partly by its adhesion to the
piston rod, and is prevented from lifting too much by stops (n, n.) The lower
extremity of cylinder B communicates at one period with the steam boiler, and
at another with the condenser through the passage G. These changes are effected
by a slide valve H, which is moved backward and forward by three tappets,
T, T, T", which move up and down with the pistons, and touch the three
levers S, S¹, S", alternately, from which levers the motion is conveyed to the
slide. The action of the engine is as follows:-High-pressure steam is
admitted through the passages K and G, and starts the weighted pistons which
were in the state of rest at the bottom of their respective cylinders. Before
one sixth part of the upstroke is completed the tappet T¹ comes in contact
with the lever S¹, which shuts the passage G by means of the lap of the slide
valve II. The impulse once received by the weighted pistons, together with
the expanding steam, carries them to the top of their respective cylinders, the
air contained in cylinder B escaping all the while through V into the atmo-
sphere, and A being filled with air from the tube through the valve D.
Whenever the tappet T" reaches the lever S" the slide valve will form a
passage for the expanded steam to the condenser M, the peculiar nature of
which I will hereafter describe. The pressure of the air on the piston (p)
into the vacuum on the other side, together with the weight of the pistons, &c.,
effect the downward stroke, and condenses the air gradually into the small
cylinder B. or partly discharges it through the valve V, from the time when
it gets equal to atmospheric pressure. Shortly before the down stroke is
completed, the tappet T, coming in contact with the lever S, admits again
high-pressure steam into the cylinder B, which causes a new stroke to
conimenice. The condenser consists of cylinder M, terminating in a narrow
cylinder or cold-water pump O. The piston (a) and plunger (6) form one

page_text: piece, the one serving as a guide for the other; a disc valve c, which is held
by the rod (d). at some period effects a communication between the two sides
of the piston through the apertures e, e, but at others it is closed down upon
these apertures. A spring (s), pressing a little projection into either of the
two recesses (i) and (i), steadies the disk valve in its proper position. The
lower extremity of cylinder M is provided with a discharge valve (f), which
leads into a large air-tight reservoir Z, which communicates with the atmo-
spheric pipe through the throttle valve (9). This reservoir must be capacious
enough to take up all the condensing water of the engine during one journey,
or about 10 minutes working, unless two such reservoirs are provided, which
may be filled and emptied alternately. This apparatus works as follows:-
The expanded steam from the steam cylinder entering above the piston a
presses it down, the disc valve being closed, and a partial vacuum being formed
below the piston, and discharges the water and air which remained in the
lower part of cylinder M since the previous stroke with great facility into the
large vessel Z, there being also formed a partial vacuum. Whenever the
piston is carried to the end of its cylinder the rod (d) touches a pin (0), which,
pressing upon the lever (h), opens the injection cock (k), and the condensation
immediately commences. The disc valve (c) is lifted at the same time, and
the pressure of the atmosphere on the water from the well forces the plunger
up till the disc valve (c) comes in contact with the top of the cylinder M, and
closes it, the air and water having had time enough to pass through the
apertures (e, e,) below the piston. The injection cock (k) is closed in the
meantime by a change in the slide valve causing the lever (7) to be moved
back by a small projection on the slide rod (m). This condensing apparatus
is not necessarily a part of the engine, but the expanded steam may be
condensed by the ordinary means, or may be used otherwise.
I will now proceed to describe a certain apparatus or governor which
regulates the supply of steam to the cylinder B, that the pistons shall be lifted
always to exactly the right point. To effect this I make provisions that the
tappet T" can be raised and lowered by turning the male or female screw
(1 and 2), the tappet itself being fixed to the female screw, which is allowed
to slide in its bearing 3. Two arms, with segments (4 and 5), are geared
into the ratchet wheels 6 and 7, as is shown more distinctly in Figure 6.
These wheels will turn the male and female screw only in one direction, but
will slide round their axes, if their segments turn them, the contrary way.
At the ends of the arms 4 and 5 are small friction rollers, which travel in
longitudinal guides 8 and 9. During every upstroke of the pistons the
female screw is turned to a certain amount by the arm 4 following the slanting

page_text: direction of the guide 8. The male screw is turned also in the same direction
by the arm 5 following the guide 9 into its curve, and if the friction roller
is brought up exactly to the point 10, then the male and female screw will
both be turned through the same angle, but whenever the arm 5 does not
reach or goes beyond this point, it will cause the tappet T¹ rather to descend
or to rise as the case may be, the consequence of which will be that it cuts
off the steam at a later or earlier period during the next upstroke of the
engine. A similar contrivance may be adapted to regulate the downward
stroke by shifting the position of tappet T, which will cause the high-pressure
steam from the boiler to enter just at the right. moment to check the fall
of the weighted pistons before they reach the bottom of their cylinders.
To shew more clearly the action of my improved pump, and how much it
is calculated to distribute the load more equally than
pump, I have drawn three diagrams, Figures 7, 8, and 9.
the very sudden resistance of an ordinary air pump when
hausted is of one fourth the density of the atmosphere. Figures 8 and 9 are
diagrams of the large and small cylinder of my improved air pump, also
exhausting air of one fourth the density of the atmosphere. That part of
Figure 8 which is marked with black section lines show the absolute resistance
in the large cylinder, and the red sectioned part in Figures 8 and 9 represents
the pressure on the small piston, which must be subtracted from the resistance
in the large cylinder to arrive at the actual power expended to compress the
air into one third of its bulk, provided there is no pressure on the opposite
side of the small piston, which, of course, must be considered separately.
an ordinary air
Figure 7 shews
the air to be ex-
Having now described the nature of this part of my Invention, and the
best mode I am acquainted with in performing the same, I wish to have it
understood that I do not confine myself to the exact details given, or to exact
proportions between the two cylinders which must vary according to cir-
cumstances. But what I claim is,-
"
.
First, the use of a double cylinder air pump for the purpose of compressing
or exhausting elastic fluids gradually, and thereby diffusing their resistance
more equally over the up and down stroke of the pistons.
Secondly, my improved systemn of applying steam power directly to ex-
hausting or compressing air, availing myself of the expansive properties of
high-pressure steam for giving movement to loaded (weighted) pistons, which
pistons in falling down compress or partly expel the elastic bodies.
Thirdly, the apparatus M for obtaining a vacuum by exhausting the con-
densing water and air into an air-tight reservoir wherefrom the air has been
partly removed.

page_text: Fourthly, the use of a governor to regulate the length of stroke of engines
without a crank.
In witness whereof, I, the said Charles William Siemens, have hereunto
set my hand and seal, this Twenty-fourth day of June, in the year of
our Lord One thousand eight hundred and forty-six.
CHARLES WILLIAM (L.S.) SIEMENS.
AND BE IT REMEMBERED, that on the Twenty-fourth day of June,
in the year of our Lord 1846, the aforesaid Charles William Siemens came
before our said Lady the Queen in Her Chancery, and acknowledged the
Specification 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-fourth day of June, in the year of our Lord One
thousand eight hundred and forty-six.