IMPROVEMENTS IN GOVERNORS FOR STEAM ENGINES AND OTHER MOTIVE-POWER ENGINES
Year: 1859

page_text: LETTERS PATENT to Thomas Elwell, of Paris, in the Empire of France
Engineer, for the Invention of "IMPROVEMENTS IN GOVERNORS FOR STEAM
ENGINES AND OTHER MOTIVE-POWER ENGINES."
ealed the 1st July 1859, and dated the 12th January 1859.
PROVISIONAL SPECIFICATION left by the said Thomas Elwell at the
Office of the Commissioners of Patents, with his Petition, on the
12th January 1859.
I, THOMAS ELWELL, of Paris, in the Empire of France, Engineer, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN GOVERNORS FOR
STEAM ENGINES AND OTHER MOTIVE-POWER ENGINES," to be as follows:-
I form the upper portions of my improved governors in substantially the
same manner as ordinary ball governors. The central vertical spindle of the
governor I make hollow throughout the greater part of its length (excepting
the upper end only) and in the hollow portion I fit a rod which is capable of
being moved up and down, or of having a tendency to an up-and-down motion
imparted to it. To the upper end of this rod is keyed a collar which embraces
and moves freely upon the tubular spindle, and which is furnished with two
lugs or eyes to which the connecting bars of the governor pendulums are
jointed. At its other end this internal rod has likewise keyed to it a ring or
washer, by preference of steel, which also embraces and moves freely upon
the tubular spindle. The said spindle is slotted to allow the keys of the ring
or washer and of the collar before mentioned to move up and down. The
tubular spindle has formed or fixed upon it two discs with friction edges or
bearing surfaces turned the lower one upwards and the upper one downwards,
and between each of these discs and the ring or washer it has also placed

page_text: loosely upon it a tube or collar carrying a corresponding friction edge or
bearing surface and a toothed wheel. The toothed wheels of the two tubes or
collars are in gear with a third toothed. wheel attached to or mounted upon a
shaft or spindle by which expansion tackle or other regulating apparatus may
be worked; the last-named toothed wheel is so fitted with leather or other
dises, &c., that when any excessive pressure is brought. upon it, it may turn
round upon its shaft. Suitable lubricating cups, &c., are provided and pro-
vision is also made for the adjustment of the various parts of the apparatus as
may be rendered necessary by wear.
The action is as follows:-When the steam engine or other motive-power
engine moves too slowly and the governor balls tend to fall, the governor bars
depress the internal rod, and this by means of the ring or washer presses the
lower loose tube or collar down, thereby bringing the lower friction surfaces
tightly together, and thus causing the said tube or collar to revolve, and by
means of its toothed wheel set the intermediate toothed wheel in motion.
The expansion tackle or other regulating parts will thus be caused to supply
more steam or to otherwise increase the power of the engine. When the
engine, on the other hand, moves too rapidly, and the governor balls tend to fly
out, the upper friction surfaces are brought into action, and in a similar
manner to that just described the intermediate wheel is moved, but in the
opposite direction, and thus the expansion tackle or other regulating parts are
caused to decrease the power applied to the engine.
.It will be observed that the characteristic feature of my Invention is this,
viz., that I transmit motion to the expansion slips by means of two pairs of
friction surfaces, one pair of which is intended to act when the speed of the
'engine is too great, and the other pair when the engine goes too slow; and
that the arms and rods of the governor are so arranged that the pressure put
on either of these surfaces by the governor is considerably (say 10 times)
*greater than the excess of the centrifugal force over the weight of the balls
on the other hand, or of the weight of the balls over the centrifugal force on
the other, and if the traction of the friction 'surfaces be equal to one-tenth,
say, of the weight put' on them by the governor, the power available for moving
the expansion slips will be equal to the difference between the weight of the
balls and the centrifugal force; this power is applied to the circumference of
the friction tables, and as the shaft that is driven by either of the loose tables
can be caused to make any number of. turns desiredlin shifting the expansion
slips from one extreme to the other, it is evident that I can obtain any 'amount
of power desired. I of course, have to determine at the outset the-length of
-time that can be employed to move the expansion slips from one extréme

page_text: to the other which is détermined by fixing the limits between which the speed
of the engine is to be permitted to vary.
:
The arrangement of parts before described is the best with which I am
at present acquainted for embodying the principal feature of my Invention,
but I do not confine myself to that arrangement, as it is manifest that it may
be varied without departing from my Invention.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Elwell in the Great Seal' Patent Office on the
12th July 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
ELWELL, of Paris, in the Empire of France, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twelfth day of January, in the year of our
Lord One thousand eight hundred and fifty-nine, in the twenty-second year
of Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Thomas Elwell, Her special licence that I, the said Thomas
Elwell; my executors, administrators, and assigns, or such others as I, the
said Thomas Elwell, my executors, administrators, and assigns, should
at any time agree with, and no others, from time to time and at all times
thereafter during the term therein expressed, should and lawfully might
make use, exercise, and vend, within the United Kingdom of Great
Britain and Ireland; the Channel Islands; and Isle of Man, an Invention
for "IMPROVEMENTS IN GOVERNORS FOR STEAM'; ENGINES AND; OTHER MOTIVE-
POWER ENGINES," upon. the condition' (amongst others), that I, the said
Thomas Elwell, my executor's or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, should
particularly describe and ascertain the nature of the said Invention, and in
what manner the same was to be performed, and cause the same to be
filed in the Great Seal Patent Office within six calendar months next and
immediately after the date of the said Letters Patent..
.
NOW KNOW YE, that 1; the said Thomas Elwell, do hereby declare
the nature of my said Invention, and; in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement thereof, reference being. had: to the Drawing hereunto annexed,
that is to say:
:
I form the upper portions of my improved governors in substantially the

page_text: same manner as ordinary ball governors. The central vertical spindle of the
governor I make hollow throughout the greater part of its length (excepting
the upper end only), and in the hollow portion I fit a rod which is capable of
being moved up and down or of having a tendency to an up-and-down motion
imparted to it. To the upper end of this rod is keyed a collar which embraces
and moves freely upon the tubular spindle, and which is furnished with two
lugs or eyes to which the connecting bars of the governor pendulums are
jointed. At its other end this internal rod has likewise keyed to it a ring or
washer, by preference of steel, which also embraces and moves freely upon the
tubular spindle. The said spindle is slotted to allow the keys of the ring or
washer and of the collar before mentioned to move up and down. The tubular
spindle has formed or fixed upon it two discs with friction edges or bearing
surfaces turned the lower one upwards and the upper one downwards; and (
between each of these dises and the ring or washer it has also placed loosely
upon it a tube or collar carrying a corresponding friction edge or bearing
surface and a toothed wheel. The toothed wheels of the two tubes or collars
are in gear with a third toothed wheel attached to or mounted upon a shaft or
Spindle, by which expansion tackle or other regulating apparatus may be
worked. The last named toothed wheel is so fitted with leather or other discs,
&c., that when any excessive pressure is brought upon it, it may turn round
upon
its shaft. Suitable lubricating cups, &c. are provided, and provision' is
also made for the adjustment of the various parts of the apparatus as may
rendered necessary by wear.
be
The action is as follows:-When the steam engine or other motive-power
engine moves too slowly and the governor balls tend to fall, the governor bars
depress the internal rod, and this by means of the ring or washer presses the
lower loose tube or collar down, thereby bringing the lower friction surfaces
tightly together, and thus causing the said tube or collar to revolve, and by
means of its toothed wheel set the intermediate toothed wheel in motion. The
expansion tackle or other regulating parts will thus be caused to supply more
steam or to otherwise increase the power of the engine. When the engine, on
the other hand, moves too rapidly, and the governor balls tend to fly out, the
upper friction surfaces are brought into action, and in a similar manner to that
just described the intermediate wheel is moved, but in the opposite direction,
and thus the expansion tackle or other regulating parts are caused to decrease
the power applied to the engine.
It will be observed that the characteristic feature of my Invention is this, viz.,
that I transmit motion to the expansion slips by means of two pairs of friction
surfaces, one pair of which is intended to act when the speed of the engine is

page_text: too great and the other pair when the engine goes too slow, and that the arms
and rods of the governor are so arranged that the pressure put on either of
these surfaces by the governor is considerably (say ten times) greater than the
excess of the centrifugal force over the weight of the balls on the one hand,.
or of the weight of the balls over the centrifugal force on the other; and if the
traction of the friction surfaces; be equal to one-tenth, say, of the weight
put on them by the governor, the power available for moving the expansion
slips will be equal to the difference between the weight of the balls and the
centrifugal force. This power is applied to the circumference of the friction
tables, and as the shaft that is driven by either of the loose tables can be
caused to make any number of turns desired in shifting the expansion slips
from one extreme to the other, it is evident that I can obtain any amount of
power desired. I of course have to determine at the outset the, length of
time that can be employed to move the expansion slips from one extreme to
the other, which is determined by fixing the limits between which the speed
of the engine is to be permitted to vary:*
.
In the Drawing hereunto annexed I have illustrated a form of governor
constructed according to my Invention. A, A, are the arms of the governor ;
B, B, are two of four links which connect the arms A, A, with the tube C, on
the end of which, and cast in one with it, is the upper driving friction piece.
This piece is caused to revolve with the governor spindle by a key fixed in the
spindle in the usual way, but at the same time it is free to slide vertically on
the key; D is the upper driven friction piece which is at liberty to' revolve
freely on the spindle in either direction; E is the lower driven friction piece
which likewise revolves freely on the spindle in either direction; F is the
lower driving friction piece. This piece is caused to revolve with the spindle
in the same manner as the piece C by means of a fixed key, on which, however,
like the other, it is free to slide vertically. On each of the loose pieces D and
E is a bevilled pinion F¹ working into a wheel G keyed on the horizontal
spindle II, communicating by means of gearing at the end (not shown) with
the expansion slides, to which the governor, when the engine varies in speed,
gives motion (independently, of course, of the motion of the excentric) in such
a manner as to admit more or less steam into the cylinder as may
be required.
The two driving friction pieces C and F are connected by means of a rod I in
the centre of the spindle, which is bored to receive it, a key in each instance
passing through the rod, the friction piece, and the hollow spindle, in all of
which it is accurately fitted, the slot or mortice in the spindle being made
of sufficient length for the key not to touch the end of it. The lower
driven friction piece E is supported by a washer K, fixed to the spindle

page_text: by means of a screw as shewn. The upper driven friction piece D is supported
by means of a washer L'and two nuts M, M; the latter being intended to take
up any play that may arise from the wearing of the surfaces. The nuts N, N;
and washer O; are intended for the same purpose for the bottom friction
piece E. The section is made through the grooves intended to convey the oil
to the rubbing surfaces which require oiling; this is the cause of the different
pieces appearing not to fit on the spindle. Of course they do fit except at the
small portion of the surfaces occupied by these grooves. The pieces D and F
contain water excepting that part of them, which is next the shaft and inside
the oil cup, and it is essential that the oil should not get mixed with the water.
The action of the governor is easily understood. The balls revolve constantly
in the same horizontal plane whatever the speed of the engine may be, but if
the speed be greater than the mean speed the bottom friction surfaces are
pressed together with more or-less intensity, and the shaft H is caused to turn;
at the same time the piece D revolves freely. If the engine slackens her
speed below the mean speed, it is the inverse that takes place, and the shaft H
revolves in the opposite direction. The frame P is in two pieces, otherwise it
would be impossible to put the spindle in its place.
;
The arrangements of parts herein-before described are the best with which I
am acquainted.for'embodying the principal feature of my Invention, but I do
not confine myself to those, arrangements, as it is manifest they may be varied
without departing from my Invention itself.
And having now described the nature of my said Invention, and, in what
manner the same may be performed, I-declare that I claim,―
First, the construction of governors for steam engines and other motive-
power engines essentially as herein-before described and illustrated in the
Drawing hereunto annexed.
Secondly, the method of transmitting motion to the expansion slips of steam
engines and other motive-power engines by means of two pairs of friction
surfaces constructed, arranged, and combined with other suitable operating
parts essentially in the manner herein-before described and illustrated in the
Drawing horeunto annexed.
In witness whereof, I, the said Thomas Elwell, have hereunto set my
hand and seal, this Fifth day of July, One thousand eight hundred
and fifty-nine.
THOMAS ELWELL. (L.S.)