IMPROVEMENTS IN GOVERNORS FOR COMPOUND ENGINES, PARTS OF WHICH ARE ALSO APPLICABLE TO GOVERNORS FOR OTHER FORMS OF MOTORS
Year: 1875

page_text: LETTERS PATENT to George Theodore Bennett, of Liverpool, in the
County of Lancaster, for the Invention of "IMPROVEMENTS IN
GOVERNORS FOR COMPOUND ENGINES, PARTS OF WHICH ARE ALSO APPLICABLE
TO GOVERNORS FOR OTHER FORMS OF MOTORS."
Sealed the 19th May 1876, and dated the 29th November 1875.
PROVISIONAL SPECIFICATION left by the said George Theodore
Bennett at the Office of the Commissioners of Patents, with his
Petition, on the 29th November 1875.
I, GEORGE THEODORE BENNETT, of Liverpool, in the County of
Lancaster, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN GOVERNORS FOR COMPOUND ENGINES, PARTS OF WHICH ARE ALSO
APPLICABLE TO GOVERNORS FOR OTHER FORMS OF MOTORS," to be as follows:-

page_text: thirdly, from the condenser; and, fourthly, to turn the steam direct
into the vacuum side of the large piston. For this purpose I usually
arrange the tappets of the respective valves in a row, and so arrange
them that a sliding or rocking beam or a chain actuates them in
succession. If the increase of speed be slight the first tappet is alone
turned, either to throttle or entirely cut off the steam; if the increase
continues, the second tappet is turned, and so on. Of course one tappet
can be made to turn both valves if requisite, or two or more of the valve
tappets could be made to work simultaneously. The valve levers are
counterbalanced by a weight or spring so as to fall back into their
normal position when the speed has been regulated by the action of the
governor; or in lieu of this, the actuating lever itself can be counter-
balanced by a spring or otherwise, and thus be made to bring the valve
tappets back their normal position.
2nd. The lever actuating the valves can be put into motion by means
of a piston sliding in a cylinder, into which a constant stream of water
is pumped by a rotary or other pump run from the engine, the discharge
being regulated by hand so as to set the steamer going at any desirable
speed. The handle to the discharge regulator can be arranged to be
worked from the deck, and constructed with a graduated arc to show
approximately the corresponding number of revolutions made by the
engine at a given pressure of steam for each position of the handle.
If the engine speed increases, the supply exceeds the discharge. The
piston and rod, and with them the connected lever and valve tappets
are moved, and the speed of the engine at once checked; the water thus
pumped can be used for condensing purposes.
3rd. It sometimes happens that the before mentioned method is
unsuitable to the particular circumstances of the ship, especially when
it has to be applied to ships already built and equipped. In its place
therefore I use the differential centrifugal principle. I place two discs
on a hollow shaft, which is run by a belt or gearing from the engine
shaft; one of these is fixed to the latter, the other loose. Between
the two discs I place two pulleys let into a recess in the fixed disc free
to revolve on their spindles, which project from the face of the said
fixed disc. These pulleys are grooved and nearly touch each other.
One end of a rope or chain is attached to the rim of the loose disc, and
the other end to the valve actuating the sliding bar or lever to the valve

page_text: tappets direct. This chain passes in the recess and between the two
grooved pulleys, and is guided by another guide pulley through the
hollow shaft to the valve apparatus in line with it. There is a swivel
on the rope or chain so as to avoid entanglement, and in addition to the
spring before mentioned and to be hereafter more particularly described,
I usually place an india buffer, or its mechanical equivalent, to take
off the shock of any sudden jerk of the chain. To counterbalance
the weight of the valve spindles I sometimes attach a pump or friction
strap to one of the disks or the shaft; a pulley attached to the shaft or
one of the discs drives the apparatus. I also arrango stops on the two
discs, which come in contact whenever the one gets a given distance in
advance of the other so as to prevent the divergence becoming too great,
and thus breaking the chain.
4th. The spring I use to counterbalance the weight of the lever or of
the valve apparatus, or of both, is of the form similar to the spring of a
watch, and a chain is wound round the spring case in a volute spiral,
precisely as in a watch or clock, so as to give it always the same
resistance whether nearly wound up or almost drawn out.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said George Theodore Bennett in the Great Seal Patent
Office on the 29th May 1876.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
THEODORE BENNETT, of Liverpool, in the County of Lancaster, send
greeting:
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-ninth day of November, in the
year of our Lord One thousand eight hundred and seventy-five, in the
thirty-eighth year of Her reign, did for Herself, Her heirs and suc-
cessors, give and grant unto me, the said George Theodore Bennett,
Her special licence that I, the said George Theodore Bennett, my exe-
cutors, administrators, and assigns, or such others as I, the said George
Theodore Benncit, my executors, administrators, and assigns, should
at any time agree with, and no others, from time to time and at all

page_text: 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 COMPOUND ENGINES, PARTS
OF WHICH ARE ALSO APPLICABLE TO GOVERNORS FOR OTHER FORMS OF MOTORS,"
upon the condition (amongst others) that I, the said George Theodore
Bennett, my executors 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 I, the said George Theodore Bennett, 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, reference being had to the accom-
panying Drawings, and to the figures and letters of reference marked
First. In arranging the governor so as to first cut off the steam from
the high-pressure cylinder Y, Fig. 9; secondly, from the low-pressure
cylinder X; thirdly, from the condenser; and, fourthly, to turn the
steam direct into the vacuum side of the large piston (cylinder X). For
this purpose I usually arrange the tappets of the respective valves in a
row, and so arrange them that a sliding or rocking beam Z or a chain
actuates them in succession. If the increase of speed be slight the
first tappet W actuating the main throttle valve is alone turned, either
to throttle or entirely cut off the steam; if the increase continues the
second tappet V is turned, and so on. Of course one tappet can be
made to turn both valves if requisite, or two or more of the valve
tappets could be made to work simultaneously. I prefer to arrange the
valves as shown in Fig. 9. In this W is the main valve tappet; V, the
tappet and valve admitting steam into the low-pressure cylinder; U, a
tappet and valve partially cutting off the steam from its exit into the
condenser. I sometimes however make V an equilibrium valve, and
connect the intermediate steam reservoir S by a pipe T with the
exhaust port of the cylinder X, and put a stop valve on this for the

page_text: governor to open instead of throttling the steam at V. The valve
levers are counterbalanced by a weight or spring so as to fall back into
their normal position when the speed has been regulated by the action
of the governor, or in lieu of this the actuating lever itself can be
counterbalanced by a spring, as shown at L, Fig. 8, or otherwise,
and thus be made to bring the valve tappets back to their normal
position.
Second. The lever actuating the valves can be put into motion by means
of a piston sliding in a cylinder, into which a constant stream of water
is pumped by a rotary or other pump run from the engine, the discharge
being regulated by hand so as to set the steamer going at any desirable
speed. The handle to the discharge regulator can be arranged to be
worked from the deck, and constructed with a graduated arc to show
approximately the corresponding number of revolutions made by the
engine at a given pressure of steam for each position of the handle.
If the engine speed increases the supply exceeds the discharge. The
piston and rod, and with them the connected lever and valve tappets
are moved, and the speed of the engine at once checked; the water thus
pumped can be used for condensing purposes.
Third. It sometimes happens that the above-mentioned method is
unsuitable to the particular circumstances of the ship, especially when
it has to be applied to ships already built and equipped. While there-
fore I consider its use will be so restricted, and I so much prefer the
alternate method hereafter described, that further description is needless,
especially as it is not a necessary part of my Invention.
The apparatus I usually adopt is shown in detail in its most improved
form on Sheets 1 and 2, in which Fig. 8 and 9 are an elevation, and
Figures 1 to 7 views of the various parts shown separately.
A is a heavy disc running loose on the hollow shaft B; C is a skeleton
disc with arms D; this disc also runs loose on shaft B; E is the
pulley for connecting the governor with the engine. Let into
recesses in the heavy disc A. I place two pulleys F, G, free to revolve on
their spindles in bearings in disc A. A cord, rope, or chain Ħ is
attached to each arm D of disc C, and the other ends to the fixed
rings I, I, in the ends of a hollow rod B¹ of the hollow shaft B. This
shaft actuates the sliding lever Z, Fig. 9, Sheet 2, and through it the

page_text: valve tappets. The aforesaid chains pass in the recesses of A over the
grooved pulleys F, G, and are guided by guide pulleys J, K, through
slots in the hollow shaft B to the said rings I, I. The shaft B' is
swivelled to the bar Z, so that while free to turn itself the bar Z can be
stationary. L is a coiled spring, so arranged that when the bar Z has
been shot out and has cut off the steam the tension of the said spring
shall aid in bringing the said bar back the instant the governor's forward
effort ceases; M, M, are two adjustable or permanently fixed stops on
disc A; N, N, are two pawls or stops on disc C kept in position by
springs P. These stops are so arranged that if ever the hollow bar or
shaft B has shot out far enough to actuate all the valves requisite the
stops N on C, which usually hold it fast to the pulley E by catching in
the ratchets or stops Q, are pressed in by stops M, and no longer
catching the two discs run round together. The moment however the
speed of the engine, and therefore of pulley E, is lessened the discs
begin to overtake the wheel E and the hinder catch N catches in the
ratches and withholds the disc. The disc C now no longer rotating as
quickly as A brings back the chain and the hollow bar or shaft B', and
consequently the valve tappets to their normal position.
Having now described my Invention and the best mode known to me
of carrying it into effect, I wish it to be understood that I do not claim
the principle of the differential governor formed of two discs, the one
loose and the other fixed, nor yet the various parts above described,
taken separately or used for any other purpose than for governors for
regulating the speed of machinery or motors; but what I believe to be
new and desire to claim under the herein-before in part recited Letters
Patent is,―
BL

page_text: of the engine cannot bring any strain on the governor, but the moment
the engine begins to slacken the governor is again brought into play.
4th. The general arrangement of governor, substantially as described.
In witness whereof, I, the said George Theodore Bennett, have
hereunto set my hand and seal, this Twenty-fifth day of May, in
the year of our Lord Eighteen hundred and seventy-six.
GEORGE THEODORE BENNETT. (L.S.)
Witness,
W. P. THOMPSON,
Patent Agent,
6, Lord Street,
Liverpool.