IMPROVEMENTS IN APPARATUS FOR INDICATING, REGISTERING, AND REGU- LATING THE SPEED OF ENGINES AND ROTATING SHAFTS, FOR MEASURING THE FLOW OF WATER OR GAS, AND FOR OTHER PURPOSES
Year: 1877

page_text: LETTERS PATENT to John Clayton Mewburn, of 169, Fleet Street, in the City
of London, Patent Agent and Consulting Engineer, for the Invention of
"IMPROVEMENTS IN APPARATUS FOR INDICATING, REGISTERING, AND REGU-
LATING THE SPEED OF ENGINES AND ROTATING SHAFTS, FOR MEASURING THE
FLOW OF WATER OR GAS, AND FOR OTHER PURPOSES." A communication from
abroad by Marie Jules Raoul Jacquemier, of Neuilly, France.
aled the 11th December 1877, and dated the 5th July 1877.
PROVISIONAL SPECIFICATION left by the said John Clayton Mewburn at
the Office of the Commissioners of Patents on the 5th July 1877.
JOHN CLAYTON MEWBURN, of 169, Fleet Street, in the City of London, Patent
Agent and Consulting Engineer. "IMPROVEMENTS IN APPARATUS FOR INDICATING,
REGISTERING, AND REGULATING THE SPEED OF ENGINES AND ROTATING SHAFTS, FOR
MEASURING THE FLOW OF WATER OR GAS, AND FOR OTHER PURPOSES." [A com-
munication from abroad by Marie Jules Raonl Jacquemier, of Neuilly, France.]
The present Invention has for its object to indicate in a permanent imanner, and
without the employment of machines of centrifugal force, the speed of an engine,
shaft, or of any moving body. Let M (Figure 1) be the plate carrying all the
mechanism; A, B, C, D, the wheels of an ordinary clockwork (A being the barrel,
and D the escapement), K is the click or paul which receives a to-and-fro move-
ment from the engine by the lever H, and causes the ratchet wheel X to advance in
the direction of the arrow mone tooth for every revolution, or half revolution, or
otherwise; T is the stop click which prevents the ratchet wheel X from going back;
Y is a second ratchet wheel which carries the indicating hand or index, and
which is capable of being pushed in the direction of the arrow m by the action
upon an abutment b fixed to it of a finger a attached to the counting wheel X.
The wheel C, which belongs to the clockwork, and makes a revolution in 30
seconds, carries an excentric Z, which, for 6 seconds, holds the lever S raised, and
consequently keeps the click K clear of the ratchet wheel X, and, without acting
upon it. The action of the counter being thus suspended, after having lasted 30

page_text: seconds, a pin s on the wheel C lifts the lever I, and consequently disengages the
stop click V from the hand-carrying wheel Y, so that if the speed has diminished,
and the finger b is in advance of the abutment d, the wheel Y, released from its
click V, and moreover solicited by a spiral spring, moves back, the finger b rests
upon the abutment a, and the pointer indicates the new speed. If, on the
contrary, the speed has increased, the hand-carrying wheel Y, pushed by the finger
a would naturally indicate the fresh speed, and would not have to move back. As
soon as this has been done, the wheel C, continuing to turn, the pin 8 lets the lever
I fall, and when the stop click V is re-engaged, as it is impossible for the pointer to
go back, the pin s raises another lever J, which disengages the click T and allows
the counting wheel X, under the action of a spiral, to return to zero, which is
determined by the stopping of the finger a against an abutment h fixed on the
plate.
At length, when all these movements are finished, that is to say, exactly 6 seconds
after the excentric Z has raised the lever S and rendered the counter inactive, it
allows the lever S to fall again; the counter recommences to move during 30 seconds,
the preceding movements are again gone through, and the pointer marks the new
speed, being moved only by the variation of speed, although the counter may be
returned to zero.
Instead of making the click K act upon a ratchet wheel of large diameter, such
as X, Figure 1, it could be made to act on a very small ratchet wheel, which would
carry a pinion engaging in a toothed wheel, which would then supply the place of
the large wheel X of Figure 1, and would carry the finger N working the pointer
carrying wheel Y.
It may be here remarked that the duration of 36 seconds for a revolution of the
excentric Z is quite optional, and that any duration can be adopted by graduating
the dial. The clockwork movement could be wound up periodically by hand, or could
be wound up in a continuous manner by the engine itself by the intermediation of
a uniform winder; or instead of the volute springs N it would be possible to
employ either a spiral spring acting on a wire wound round a small arbor attached
to the ratchet wheel, or a spring acting upon a rack engaging with a pinion fixed to
the ratchet wheel, the excentric Z, which raises the levers S, should cause the click
K to disengage by a sharp and instantaneous movement, so that if the shocks
which naturally result from the escapement are not sufficient, one of the arrange-
ments known as cataracts, surprises, star wheels, and the like, or the the following
method (Figure 3) could be employed.
The two excentrics, E and F, are fastened together and keyed upon the arbor of
the clockwork, which turns in the desired time; the lever B, C, D, separates the
click A from its ratchet wheel Y at the exact moment that the pin B falls from the
point H of the excentric E, and the engagement of the catch A in the ratchet wheel
Y will be effected equally at the precise moment that the pin N of the two
armed lever, M, R, N, falling from the point S of the excentric F, the arm R, M,
under the action of the spring Z, which is more powerful than the spring X, pushes
back the lever B, C. All that is necessary, therefore, is to regulate the distance of
the two points B and S of the two excentrics to have the desired .period; the lever
R, N, after having fallen from the point S will be afterwards gradually raised by
the ascending portion K, J, of the excentric.F.
In Figure 3 there are supposed to be two periods for a revolution of the arbor V;
there may, however, be any number, but it is then necessary to have an equal
number of pins analogous to S in Figure 1.
The principle of this speed indicator being the direct measure by the wheel X,
Figure 1, of the distance traversed by the engine or moving body in a certain time,
the movement of the engine can be communicated to the ratchet wheel X by any
engaging apparatus of circular motion. Thus, if we do away with H and K in
Figure 1, and suppose that the lever R can cause in one direction the engagement,
and in the other the disengagement of the ratchet wheel X with the engine, the
wheel X will turn at each period an angle proportional to the distance traversed by

page_text: the engine in that period, and this angle will-represent, as before, the speed of the
engine.
.
Figure 4 represents a modification; A, B, is a shaft which receives the motion of
the engine by the wheel or pulley C; the lever D, E, of the epicycloidal train
H, E, K, is keyed upon this shaft, and turns with it, say, for example, from left to
right; the wheels K and H of this train carry each a ratchet wheel M and N, with
stop clicks P and R, and the teeth of these ratchet wheels are such that the click R
prevents the ratchet wheel N turning in the direction of the shaft A, B, and that
the click P prevents the ratchet wheel M turning in the other direction; so that
the ratchet wheel M (which plays exactly the same part as the counting ratchet
wheel X of Figure 1) is capable in moving in the direction of the shaft A, B, of
making another ratchet wheel V, which carries the pointer, advance by means of a
finger. The two wheels M and N are solicited in the reverse movement by springs
as in the preceding arrangements.
The wheel C, and consequently the lever D; E, of the epicycloidal train, turning
with the speed of the engine, and from left to right if the click R is engaged in the
ratchet wheel N, and consequently preventing this wheel being drawn by D, E, the
click P acting only in the other direction upon the ratchet wheel M; this latter
will be drawn with a speed double that of the shaft A, B, and in the same direction:
At the end of 30 seconds the click R will be disengaged from the ratchet wheel N,
which will then be drawn, whilst the wheel M, which is solicited by its spring in
a reverse direction, will stop, being moreover unable to go back, as it is stopped by
its click P: This wheel will thus have traversed during the space of 30 seconds a
distance proportional to that of the engine, and consequently its rotation represents
the speed. It will therefore be sufficient, as in the preceding arrangements for the
movement of the clock work, shortly after the stoppage of the wheel M, to cause the
click S to disengage and re-engage, so that the wheel V carrying the pointer
may join if necessary the counting wheel M; then the click P being afterwards
disengaged from the wheel M by an excentric analogous to E (Figure 3) the wheel
M (Figure 4), solicited by its spring, returns to zero, which is then possible, as the
wheel K of the epicycloidal train, having no resistance to overcome, can increase
the speed in consequence.
When once the ratchet wheel M has returned to zero, the click R will again be
abandoned by its excentric, and will consequently re-engage in the wheel N; the
counting wheel N will again begin to turn in the direction of the shaft A, B, and
with a double speed, and all the preceding actions are repeated. In short, the two
clicks S and P play identically the same part as the. clicks V and T of Figure 1,
and they are lifted in the same manner and at the same instants by pins analogous
to the pins of that Figure. With regard to the click R, Figure 4, when it engages
with the wheel N it causes the rotation of the counting wheel M, and when it is
disengaged therefrom it stops the latter; it therefore plays exactly the part of the
lever B, C, D, of Figure 3, and it will be worked by the same arrangement of
excentrics E and J and supplementary lever M, N, R.
:-
In some cases it will be advantageous to place the excentric Z and the pins of
Figure 1, not on one of the arbors of the clockwork, but on an arbor of auxiliary
wheelwork, and the arbor of the clockwork will at each period only cause the
detent of the auxiliary wheelwork to escape. Electricity can thus be employed:
The excentric Z and the pin's (Figure 1) having, for example, only to establish con-
And likewise
tacts in order that the electro-magnets may actuate the levers I, J, S.
electricity may serve to communicate to a distance the movement of the engine to
the click K and other parts; or this click may receive its to-and-fro movement by
means of a simple wire, or by a caoutchouc tube, as in bells worked by compressed
air.
=
The employment of continuous circular engaging apparatus allows of using
sufficiently short periods or intervals for the indicated speed to differ little from the
theoretical speed, that is to say, from the derivative (derivée) of the space in
relation to the time, the instrument thus becomes a true differentiating apparatus,

page_text: :
The following is another modification:-Whatever be the mode of actuating the
ratchet wheel X, Figures 1 (circular engaging apparatus or click apparatus),
suppose that the excentric Z, instead of being worked by the clockwork, be con-
nected to the engine, and that the click K be worked, not by the engine, but by the
clockwork, the instrument remaining otherwise the same, the pointer will not
indicate the number of revolutions of the engine in 30 seconds, but the time
necessary for the excentric Z, which is connected to the machine, to make a
revolution.
Applications. The first application of the instrument or apparatus is to indicate
the speed of engines of any description, and for this application it is called an
anemometer. Graduated into miles it will give the speed of a locomotive; applied
to a small screw, moved in the wake of a vessel, it will give the speed in knots of
this vessel. It can be adapted to an ordinary anemometer, so as to give its
speed of rotation, and consequently the velocity of the wind; it will likewise
measure the velocity of a current in a river, and the delivery of a liquid or gas; it
can specially be used as a water or gas meter.
In all its applications the indications of the pointer can be registered; for this
purpose there is fixed on the spindle of the pointer a pulley, on which is wound a
wire attached to a pencil drawn in the reverse direction by a counterweight. The
pencil will trace a curve on paper unwound by clockwork; or the two ratchet
wheels X and Y, of Figure 1, may be replaced by two straight racks, the first
actuated by the click K, the second carrying the pencil or marker.
The anenometer may also be used as a regulator to maintain constant and at a
given speed the working of a steam, hydraulic, or other engine. For this purpose,
the pointer, Figure 2, is connected to the first wheel A, Figure 5, of an epicycloidal
train A, B, C, and the wheel C of this train is worked by hand, and can be fixed on
any division of a dial. The lever B, D, of the train is connected to the steam valve,
or rather to an engaging apparatus, which puts the valve in motion. When the
speed indicated by the pointer corresponds to the position given by the attendant
to the wheel C, the lever B, D, leaves the steam valve immovable; but if the speed
changes, the lever B, D, is displaced, and causes the valve to move in the proper
direction. The movement of wheelwork, driven by weights or springs, can be
regulated by the same means to a uniform speed by making the lever B, D, Figure 5,
to operate on the tail of a break acting on the wheelwork to moderate it more or
less. There is thus obtained a clockwork movement of great power and uniform 3
motion without jerks for parallactic instruments, lighthouses, printing telegraphs,
and other apparatus."
Another application consists in combining with it a rotating dynamometer, so as
to obtain on a dial the permanent indication of the horse power of a motor; for this
purpose the speed pointer will carry an excentric, the radii-vectores of which will 4
express the logarithms of this speed; the pointer of the dynanometer will also
carry an excentric, the radii-vectores of which will express the logarithms of the
force or momentum of rotation. The two excentrics actuate two levers, the move-
ments of which are transmitted to the wheels A and C, Figure 5, of an epicycloidal
train A, B, C. It is known that the movement of the lever B, D, which will be 4
read on a dial, is equal to half the sum of the movemiemts of A and C, therefore
equal to half the sum of the logarithms of the speed and of the mementum of
rotation, and consequently it is equal to the half logarithms of their product, which
expresses the horse power of the motor.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Clayton Mewburn in the Great Seal Patent Office on the
1st January 1878.
JOHN CLAYTON MEWBURN, of 169, Fleet Street, in the City of London, Patent
Agent and Consulting Engineer. "IMPROVEMENTS IN APPARATUS FOR INDICATING,
REGISTERING, AND REGULATING THE SPEED OF ENGINES AND ROTATING SHAFTS, FOR
MEASURING THE FLOW OF WATER OR GAS, AND FOR OTHER PURPOSES." (A com-
munication from abroad by Marie Jules Raoul Jacquemier, of Neuilly, France.)
The object of the apparatus which forms the subject of the present Invention is
to indicate in a permanent manner, and without the employment of centrifugal
apparatus, the speed of an engine, shaft, or other moving body, the indication being
made by a hand or index on a dial following exactly the variations of the speed to.
be measured without returning to zero.
The principle of the Invention consists in causing the body in motion to act on
the mechanisin of the indicator, at given intervals of time, always of the same
duration, and each of which serves as a unit of time in order to estimate the
displacement of the part whose speed has to be measured.
In order to carry out this principle, I transmit the movement whose speed has to
be estimated by a lever and a click to a ratchet wheel, which is submitted to this
action only during the interval of time above specified, and which, the said interval
having elapsed, should return to its point of departure, being drawn back by a
spring. But before this return movement takes place the ratchet wheel has moved
a second ratchet wheel which carries the indicator or hand, and has shifted it to the
división which corresponils to the course or distance traversed during the unit of
time, that is to say, to the speed. The connection between the two ratchet wheels
is such that during the return movement of the first the hand-carrying ratchet wheel
remains in its place and does not leave it until the end of the next following interval
of time, if the speed has been modified. It is by means of a clock movement that
the intervals of time are measured, and the releasing motions produced which allow
of the return of the ratchet wheels.
In some cases, when it is not required to measure the speed in a permanent
manner, for example, instead of rendering the action entirely automatic the releasing
motion of the first ratchet wheel can be produced by hand, and the apparatus is.
therefore much simplified, the second ratchet wheel being unnecessary.
Having explained the nature or principle of the apparatus, I will proceed to
describe its construction and action with the aid of the annexed Drawings.
Figure 1 is a front view of the apparatus, the box which encloses it being removed.
Figure 2 is a side view, and Figure 3 a back view..
A lever A, actuated directly hy the engine shaft or other moving part whose
speed is to be ascertained, oscillates at the point O and moves the counting ratchet
wheel B by means of the click C. The wheel B communicates its movement to the
second or hand-carrying ratchet wheel D (mounted on the arbor O¹) by the aid of
the pinion E, toothed wheel F, and lever G, which is fixed to the wheel F, and acts
on a small pin a on the wheel D. Two stop-clicks, H and I, act respectively on
the two wheels, B and D.
The action of the apparatus is as follows:--- -The apparatus being at rest, the hand
is at zero on the registering dial; when the engine or other moving body is in
communication with the apparatus the oscillations of the lever A cause the wheel B
to turn, and consequently the wheel D, during the interval corresponding to the unit
of time. This interval is exactly measured on the apparatus by a clock movement.
At the instant this interval expires a pin b bears on the lever c, and by this means
the stop-click H is lifted. At the same time a scapement g of the clock movement
separates the click C from the wheel B by means of the levers h, h¹. The wheel B
being then submitted. simply to the action of a recall spring r, through the inter-
mediation of the toothed arc d, returns to its point of departure, which is determined

page_text: by the meeting of the pin e on the wheel F with the pin f, fixed to the disc P, which
supports the mechanism. During this return motion the wheel D remains stationary
and the hand K at rest indicates on the dial the number of turus of the engine or
other moving body during the unit of time. The separation of the click C lasts for
a time perfectly determined, and the same scapement g at the end of some instants
brings it back into contact with the wheel B. The advance motion of this wheel
again takes place during the unit of time. If the speed of the engine or other body
has increased, the wheel B will be turned a greater number of teeth, and in its
movement will cause the wheel D, and therefore the hand, to advance. If, on the
contrary, the speed of the engine or body has diminished during this unit of time
some instants before the release of the wheel B a second pin b, by acting on the
lever c¹, will have released the click I, and the wheel D being submitted to the
action of the recall spring 7', through the intermediation of the toothed arc d¹, will
move backwards until its pin a comes against the lever G fixed to the wheel B. In
the case where the speed had increased the release is produced in the same manner,
but, as when it was affected, the lever G was in contact with the pin a, the return
movement did not take place; on the contrary, the wheel D was drawn into the
forward movement.
At the expiration of this second interval of time the same effects are produced,
and all the parts of the mechanism are in the same conditions as at the expiration
of the first. The subsequent action of the apparatus will be exactly as in the second
unit of time, and the speed of the engine will be measured at very regular intervals
of time and as frequently as may de desired, always fixed by the clock movement.
Sometimes it is well to know the speed of a machine or other body but only
occasionally, and for this purpose the apparatus is arranged as shewn in front view
and in sectional elevation in Figures 4 and 5. The lever A imparts the motion of
the shaft to the ratchet wheel B by the intermediation of the click C, and it is the
wheel B which carries the indicating hand D. The interval of time corresponding
to the unit of time during which the trial or test is made is measured by a clock
movement. The barrel E carries a disc F which has a notch. On this disc bears a
small pin a mounted on a bent lever L. When the pin a falls into the notch of the
disc F, a second pin a mounted on the other arm of the lever raises the click C,
and thus the wheel B and hand D remain stationary. By pressing on the button G
the stop-click H no longer acts on the wheel B, and the spring R returns this wheel
and the hand to zero. The apparatus is then ready for another trial or test.
It will be seen that this simplified arrangement acts on the same principle as that
previously described, except that the release which returns the ratchet wheel to its
point of departure is produced by hand.
.
The principle of the speed indicator being the measure of the course or travel
during a given time, the motion from the engine to the counting ratchet wheel can
be transmitted by any suitable engaging apparatus of circular movement in place of
the lever and click. The connection of the two ratchet wheels can also be effected
by an epicycloidal train.
The employment of continuous circular engaging apparatus would permit of
sufficiently reducing the periods to allow of the speed differing little from the
theoretical speed, that is to say, from the derivative (derivée) of the space in relation
to the time; the instrument would thus become a true differentiating apparatus.
Whatever be the arrangement adopted the apparatus is capable of several
applications. Employed to measure the speed of engines, it may be called an
anemometer. Graduated into miles, it will give the speed of a locomotive; applied
to a small screw moved in the wake of a vessel it will give the speed in knots of this
vessel. It can be adapted to an ordinary anemometer, so as to give its speed of
rotation, and consequently the velocity of the wind; it will likewise measure the
velocity of a current in a river, and the delivery of a liquid or gas; it can specially
be used as a water or gas counter.
In all its applications the indications of the hand can be registered; for this
purpose there is fixed on the arbor of the hand a pulley on which is wound a wire

page_text: or cord attached to a pencil drawn in the reverse direction by a counterweight; the
pencil will trace a curve on paper unwound by clockwork. The anemometer may
also be used as a governor or regulator to maintain constant and at a given speed
the working of a steam, hydraulic, or other engine.
Another application is the combination with the apparatus of a rotating dynamo-
meter, so as to obtain on a dial the permanent indication of the horse power of a
motor. For this purpose the speed pointer will carry an excentric, the radii-vectores
of which will express the logarithms of this speed; the pointer of the dynamometer
will also carry an excentric, the radii-vectores of which will express the logarithms
of the force or momentum of rotation; the two excentrics actuate two levers, the
movements of which are transmitted to the wheels of an epicycloidal train.
And having now described the nature of the said Invention and in what manner
the same is to be performed, I declare that I claim,―
First. Constructing apparatus by means of which a permanent indication of the
speed of an engine or other moving body is given by a hand which is moved on a
dial, in exact accordance with the variations of the speed, without returning to zero,
substantially as herein-before described, and represented in the annexed Drawings.
Second. The employment of a clock movement, for the purposes herein-before
explained, in combination with the special mechanism herein-before described, which
produces the forward and backward movement of the hand to an extent
corresponding to the variation of the course or distance travelled in two successive
intervals of time, substantially as herein-before described.
Third. The several arrangements of apparatus herein-before described, and
represented in the annexed Drawings, for the purposes explained.
Fourth. The application or adaptation of the said apparatus to steam, hydraulic,
or other engines, either as speed indicators, or as governors, or regulators, or as
indicators of horse power to anemometers or apparatus for measuring the velocity
of fluids or liquids in pipes, canals, rivers, or otherwise; to register the speed of
trains, ships, and generally bodies in movement, substantially as herein-before
described with reference to the annexed Drawings.
In witness whereof, I, the said John Clayton Mewburn, have hereunto set
my hand and seal, this Twenty-first day of December, One thousand eight
hundred and seventy-seven.
J. C. MEWBURN. (L.S.)