A CONTINUOUS SPEED RECORDER
Year: 1878

page_text: LETTERS PATENT to Auguste Alfred Lebreton, Engineer, of No. 1, Rue
Laffitte, Paris, France, for the Invention of "A CONTINUOUS SPEED RECORDER."
PROVISIONAL SPECIFICATION left by the said Auguste Alfred Lebreton at
the Office of the Commissioners of Patents on the 12th October 1878.
AUGUSTE ALFRED LEBRETON, Engineer, of No. 1, Rue Lafitte, Paris, France.
"A CONTINUOUS SPEED RECORDER."
The object of this Invention is to render permanently visible the variations of
the speed of a motive-power engine, by indicating the number of revolutions it
makes per minute or in any other fraction of time. The principle of this applica-
tion is based on the constant and automatic replacing in equilibrium of a tempering
speed with any given speed of a motive-power engine.
In order to explain this Invention I will describe it conjointly with the four
Figures of the accompanying Drawing, in which Figure 1 is a lateral elevation of
my mechanism; Figure 2, a back elevation of the same with the back plate removed;
Figure 3, a second lateral elevation of the same seen on the side opposite to the one
shown in Figure 1; and Figure 4, a front elevation of the same with the indicating
hand and front dial plate removed. In these Figures the mechanical agent which
effects this constant replacing in equilibrium is a pendulum of variable length, the
weight or bob 1 of which is made to rise or to fall on the rod 2 in such a manner that a
given length of the pendulum is made to correspond with a given speed of
the motor.
Motion is imparted to the pendulum 1, 2, automatically in the following manner :-
The motive engine imparts rotary motion to the shaft 3 which turns in the plates
4, 5. within which plates it carries a spur wheel 6, gearing in a similar wheel 7, to
which is attached a pinion 8; these two gears 7, 8, turn freely in a plate 9, one
end of which is pivotted on the shaft 3, whilst the other is traversed by a slot hole
in which is set a pin 10, with a nut 11 to tighten the same against the plate 4;
Price 1071

page_text: the object of this arrangement is to be able to change according to the requirements
the speed imparted to the mechanism by the motor through the shaft 3, for which
purpose I make use of change wheels 7, with different sized pinions that are
brought into gear with the large wheel 12; to this wheel is attached the bevel gear
13, which in its turn gears on either side with the satellite bevil gears 14 and 15,
these two latter in their turn gear in a bevil wheel 16, which is attached to a spur
wheel 17 similar to the one 12. The coupled gears 12, 13, and 16, 17, run loose on
the shaft 18, whilst the axis of the bevil gears 14 and 15 are adapted to the ring 19,
which is attached to the shaft 18 by means of screws 20.
The spur wheel 17 gears in a pinion 21, to which is attached a wheel 22, gearing
in a pinion 23; on the spindle of this latter pinion is fixed an arm 24, having a
projecting pin 25, which acts as an escapement wheel for a Graham anchor 26, the
axis of which is supported in the plate 24, and in a bearing 27, and has suspended
to it the pendulum rod 1, with its bob 2, which latter is provided with four friction
rollers 28 that embrace the sides of the rod. The bob or weight 2 is suspended by
a silk thread 29, the lower extremity of which is attached to an eye 30, from thence
rising over the pulley 31 ; its other extremity is attached to the end of the arm 32
of a double lever (see Figure 4), hung loosely on the axis 18; the other arm 33 of
this lever is provided at its extremity with a spring pawl 34, which enters the teeth
of a ratchet wheel 35, fixed to the plate 5, and centered on the shaft 18. This
pawl or ratchet 34 is fitted on a tube, the other extremity of which is provided with
a tail piece 36.
A lever 37 is fixed on the spindle 18, under the lever 32, 33, with the object of
raising this latter by its contact with a strong pin 38, struck in the arm 33, and of
depressing the same, the contact on the tail piece 36 of the ratchet 34 of a pin 39,
fixed on the inner face of the said lever 37, thus disengaging the ratchet 34 from
the teeth of the wheel 35, and allowing the pendulum bob 2 to descend, its weight
by means of the thread 29 causing the lever 32, 33, to oscilate on its axis; this
arrangement of parts is completed by a spiral spring 40, which is attached by one of
its extremities to a small arm 41, fitted on a square formed on the outer extremity
of the spindle 18, and by its other extremity to a hook 42 fixed in the plate 4.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Auguste Alfred Lebreton in the Great Seal Patent Office on the
9th April 1879.
Auguste ALFRED LEBRETON, Engineer, of No. 1, Rue Laffitte, Paris, France.
"A CONTINUOUS SPEED RECORDER."
The object of this Invention is to render permanently visible the variations of
the speed of a motive-power engine. The first part of the Invention consists in a
mechanism for indicating the number of revolutions made by the machine per
minute or in any other fraction of time, whilst by the second part the system of
indication of speed is completed by not only marking the whole amount of revolu-
tions effected during a certain time of working of the motor, but by also permanently
showing the highest and lowest speed attained by the motor during this time.
The 13 Figures of the accompanying Drawings form a part of this Specification.
Figures 1, 2, 2a, 2b, 2, 3, 4, and 5 referring to the first part, whilst Figures 6, 7, 8,
and 8 illustrate the second part of the Invention: a Figure 9 is a view of the
entire mechanism, suitably arranged and ready for use.
First part, indicator for showing the number of revolutions per minute, Figures
1, 2, 2a, 2b, 2, 3, 4, 5.
Figure 1 is a front elevation of the mechanism with the dial removed; Figure 2
is a back elevation of the same with the parts carried on the principal shaft shown
in section; Figure 3 is a cross section in the line of the anchor shaft; Figure 4 is
a plan with the upper part of the mechanism removed and partly shown in dotted
lines; Figure 5 is a diagram representing the mode of operation; Figures 2ª and
2b show in section details of some parts carried on the principal shaft, and Figure
2c is a plan of these parts.
The framing is cast in one single piece with the bed plate. It consists of a front
plate F. with two wings A, A, projecting backwards therefrom and connected
with each other by a cross piece T. In these wings and in the cross piece
respectively are fixed the four bearings of the two shafts, viz. :-
1. The main shaft L, receiving its motion directly by means of a belt and pulley
(as shown in Figure 9), or by any other suitable means from the machine, the speed
of which it is desired to indicate, and carrying exterior to the wing A a large gear
wheel M. 2. The principal shaft P, having exterior to the wing A a pinion p, of
variable diameter according to the different velocities for which the indicator is
constructed. This pinion p gears into the wheel M, the latter is consequently dis-
placed according to the diameter of the former.
The principal shaft P carries interior to the framing three series of elements.
1. A case b, containing a spiral spring similar to a watch mainspring, that is
to say, hooked at its interior end to the principal shaft P (which consequently per-
forms the functions of a winding shaft), and at its exterior end attached to the
interior wall of the casing b.
2. A system of differential screw composed of a nut e on the principal shaft,
which latter is correspondingly threaded. The ears or projections of this nut are
capable of smoothly sliding in the two longitudinal slots of an open cylinder c,
which I will call a lantern, and one end of which is slipped over the casing b and
firmly connected therewith by means of small screws. The ears of the nut e project
beyond the surface of the lantern and support a pulley f, fixed upon them by small
screws. The other end of the lantern is formed with a clutch wheel r, which
engages with a similar ciutch wheel, placed opposite. The hub t of this latter is
made to penetrate into and fit smoothly in the lantern C, thus forming a support
for the same. This wheel carries on its other side four projecting arms a, a.
3. The escapement wheel consisting of a flat oblong piece O, held between the

page_text: arms a, a, of the wheel 1, so that it has to follow the movement of these arms by
reason of the lateral contact, whilst the latter are free to change their position
longitudinally. A spiral springs is interposed between the wheels and 0 to
keep two wheels and engaged, and at the same time to admit of their disconnec-
tion by being compressed, when the advancing of the nut e pushes the wheel >
backward by its hub coming in contact with the centre of the nut. The ends of
the piece O are turned over at right angles in opposite directions, and in each of
these laterally projecting ends is set a pin c. These two pins are consequently in
diametrical opposition and are placed at equal distances from the vertical plane
laid through the centre of the piece O. This escapement wheel is mounted on a
sleeve on the other end of which is fixed a double finger D, serving to prevent the
jumping back of the pins c from the anchor V at cach semi-revolution of the entire
system of elements carried on the principal shaft P. For this purpose the double
finger strikes against the end of the spring pawl d, fixed on the interior face of the
wing A, and which permits the motion in the proper direction, whilst it prevents the
revolution of the parts in the opposite direction.
These three series of elements are loose on the principal shaft P.
The pins c, c,
of the escapement wheel O act alternately on the inclined planes of the side auchor
V, firmly mounted on a transverse rock shaft which is supported in the cross piece
T and a bridge arranged on the exterior face of the front plate F which is cut out
to let the shaft pass through it. On the latter, near the front plate, is mounted
the pendulum guide G, on which the pendulum weight is capable of sliding up and
down. In order to admit of this vertical displacement, the latter is provided with
two symmetrically placed rollers g, g, in the grooves of which the edges of the
guide rod G are engaged. The weight t is suspended on a steel band S, which
passes through a confining piece h, fixed on the bridge E, above which point it is
inserted in a collar i, turning on the pin d, projecting forward from the end of the
double lever J. The latter forms part of the general system which serves to vary
the length of the regulating pendulum according to the different variations of the
speed of the motor.
This system is arranged in the following manner :-
Between the flanges of the pulley f is engaged a roller j, turning at the end of a
stout pin projecting downward from the extension of a segment K. This segment
oscillates on a pin set in the upper face of a flat bridge U, fixed by means of screws
on the edge of the front plate F, and engages with a pinion u, turning between a
small bridge v, supported on the flat bridge U, and a second small bridge vl, fixed
to the front plate F. With this pinion the endless screw u' is compelled to turn,
acting on a small wheel u", which forms part of the central part of the balance
lever X, and oscillates with the latter on the stout pin x set in the front plate F.
This balance lever carries at one of its ends a pin ẞ, on which turns the above-
mentioned double lever J, which as above stated carries on one of its extremities
the pin d, forming the point of suspension for the regulating pendulum. From the
other extremity of this double lever extends backwards a long pin j, capable of
sliding in a horizontal slot formed in a lateral extension of the front plate F. The
three lengths B, Bj, and Bd being equal, and the point j being compelled to move
in a horizontal straight line, it is evident that the point j must move in a geomet-
rically straight line when a partial revolution of the balance lever X takes place,
which is effected by its being operated upon by the wheels K, u, u', u', which in
their turn are controlled by the pulley f
In conclusion of this description I will mention that to the free end of the balance
lever X is connected a rod y, the other end of which is connected to the crank arm z
mounted to the sleeve z¹, which carries the index hand N on the exterior face of
the index plate W. The sleeze ¹ turns on a stud ¹¹ set in an extension of the front
plate F.
Two counterweights X and X' are arranged to balance the weight of the pen-
dulum bob l, so as to reduce the resistance to the mere friction on the axis.

page_text: OPERATION.
Supposing the escapement wheel to apply against the rest of the anchor and the
regulating pendulum to have passed beyond its vertical line.
The main shaft turning continuously will by means of the gear wheel M
and pinion p impart a rotory motion to the principal shaft P, and the latter
forming, as above stated, the winding shaft for the spring in the casing b will
wind up the said spring, provided that the general system, the different parts
of which casing b, lantern C, clutch wheels r, r, and escapement wheel ○ are
connected between each other, be kept stationary in consequence of one of
the pins c, c, pressing against one of the rests of the anchor; the spring will
consequently be wound up to a degree corresponding to the duration of the
vibration of the pendulum, and the nut e will during this period horizontally
advance toward the escapement wheel O. When in consequence of its oscillation
the pendulum again advances towards its vertical line the pin, which previously
pressed against the rest of the anchor, will find itself opposite the V shaped open
place in the latter. At this monent the escapement will take place, and the general
system not being restrained any longer will turn, the spring will be wound off and
thereby cause all the parts connected with each other to turn, thus screwing the
nute on the shaft P, whereby the former will be drawn back toward the casing b.
By passing over one of the inclined faces of the anchor V the pin which was pre-
viously arrested will give a new impulsion to the pendulum, as is the case in all
escapements known, and the other pin in its turn will come to rest on the other
side of the anchor; during the new vibration of the pendulum the same effect will
naturally be produced again, and consequently the nut e will receive a to-and-fro
motion along its shaft, advancing toward the escapement wheel during the time
when one of the pius c rests against the anchor, and returning toward the casing b
at each escapement. If therefore the length of the regulating pendulum corresponds
with the speed of the motor, that is to say, if the spring during the periods when
one of the pins c rests against the anchor becomes wound up to the same amount as
it can wind itself off during the periods when the escapement takes place, which
is dependent upon the perfect accordance of the duration of the pendulum vibration
and the duration of the winding of the spring, then the to-and-fro movement
of the nut e will constantly take place in the same limits; the roller ; on the
extension of the segment will therefore remain stationary between the flanges of
the pulley f, which effect is obtained by the width of the pulley between its flanges
being larger than the diameter of the roller j; but if the speed of the motor increases
the accordance between the durations of winding up and the pendulum vibrations
will cease, because the length of the regulating pendulum has not been changed;
the consequence will be that the spring during the period when one of the pins c
rests on the anchor is wound up to a greater amount than it is wound off during
the escapement, the nut e will advance further than it can recede, the right
(Figure 2) flange of the pulley f coming in contact with the roller ; will push along
the latter, and consequently impart motion to the segment K and the wheels
u, u, u, whereby the balance lever X is turned in the direction to elevate the
pendulum weight 1, whereby the pendulum is shortened and the rapidity of its
vibrations regulated. At a given moment the duration of the vibrations will there-
fore automatically be brought to correspond exactly with duration of winding up by
the motive power at this moment, the equilibrium being re-established between the
winding and unwinding of the spring, the nut e will not advance any further, and
consequently the pendulum weight will cease to rise.
When on the contrary the speed commences to slacken the same effects will be
produced in the opposite order, that is to say, the spring not being wound up during
the periods when the pins c press against the anchor to an amount corresponding
to the unwinding during the periods of the escapement, the nut e will retreat
towards the casing b, and the left (Figure 2) flange of the pulley f will push the

page_text: system which regulates the length of the pendulum in the direction corresponding
to the descent of the pendulum weight 1, that is, in the direction for elongating the
pendulum, thereby rendering the vibrations of the latter of longer duration; con-
sequently the equilibrium between the winding up and unwinding of the spring will
at a given moment be again automatically re-established, the nut e will cease to
retreat, and the pendulum weight to descend.
It follows from this explication that to any speed of the motor naturally corre-
sponds a certain length of the pendulum, and as to every length of the pendulum
corresponds a certain position of the balance lever X, the connecting rod y, and the
arm, the indicator hand N fixed to the sleeve of the latter must necessarily in a
permanent manner indicate on the dial W the exact speed of the motor.
The cinematic disposition of the three levers X, y, z, renders it possible by
conveniently chosing their respective lengths to obtain an increasing progression in
the angular ways traversed by the arm for equal ways traversed in the same time
by the lever X; in this manner an increasing progression can be easily found for
the partial revolution of the arm z, exactly inverse to the decreasing progression of
the lengths of the pendulum, it is known that the duration of the vibrations is
proportionate to the square root of the lengths, which for each gives a velocity
becoming greater and greater as the pendulum is shortened, the differences between
the respective lengths become less and less, thus in consequence of the above-
mentioned cinematic arrangement a compensating effect is produced, which permits
to obtain on the dial equal divisions for the different velocities.
If the speed of the motor exceeds a certain limit the centre of the nut e will
strike against the hub t of the clutch wheel ¹, and in this manner disengage the
latter from the opposite wheel which forms part of the lantern c by compressing
the spiral spring 8. The lantern not being restrained now any longer the spring in
the casing 6 will unwind itself freely, causing the lantern to turn and consequently
the nut e to move backward, whereupon the spiral spring s will again effect the
engaging of the clutches and . By this disposition the excess of the winding
up of the spring resulting from a too high speed is taken up without any
inconveniences arising therefrom for the general junctions of the apparatus.
Second part. Differential counting machine.
As an adjunction to the above-described apparatus, completing the system of
indication of speed of any motor, I have hereto annexed an apparatus represented
in Figures 6, 7, 8, 8, which by marking the number of revolutions made in a given
time permits to reckon the average speed the motor has obtained during this time,
and which besides marks the revolutions made above and below the regular speed
during such given time.
This result is obtained through the variations between the speed of the motor
and a chronometric speed by means of a differential train of conical gear wheels,
one of these wheels being driven by a wheel forming part of a train of gearing
which itself receives motion from the main shaft of the apparatus; the opposite
wheel of the differential train (connected with the first by a third conical wheel,
which operates as satellite wheel) being driven by one of the wheels of the chrono-
metric train. This chronometric train consists of a mainspring analogous to that
described with reference to the indicator, which is constantly being wound up by a
wheel of the train that imparts motion to the entire apparatus. The movement of
this chronometric train is regulated by an escapement formed by a wheel, in the
face of which is set a number of pins, and which receives its motion from the spring
through a series of gear wheels.
It follows from these arrangements that the two conical wheels which receive
their motion respectively from the main shaft and from the chronometric train,
being loose on the shaft of the differential train, and the satellite wheel being fixed
thereto, this shaft will revolve in one direction or the other correspondingly to half
the difference of the velocities. By suitably arranging on this shaft a double 5
system of pawls, it is therefore possible to operate two trains of gearing, representing

page_text: the number of revolutions and the number of revolutions below the regular
speed, and by adding to these indications that of the minutes of running, all the
elements necessary are given to find the maximum and minimum, and the average
speed as well as the number of revolutions effected.
The Figures 6 to 8a, represent this part of the Invention. Figure 6 is an eleva-
tion taken from rear side, some parts being represented in section; Figure 7
is a side elevation; Figure 8 is a view corresponding to Figure 6, with the rear
plate removed; Figure 8ª, shows a detail in section.
The apparatus consists of two casings, viz.: —
1. The large or principal casing formed by two rectangular plates P and P¹,
connected in the ordinary manner by posts screwed in between them, and fixed to
the bed plate by stout bolts screwed into the middle and through the lower posts.
2. The small casing formed by two small plates p and p³, connected with each
other by three bars b, b', b²; the two latter in their turn are screwed to the exterior
face of the large plate P.
The large casing supports in its interior and on its faces the following parts:-
Three conical gear wheels 1, 2, 3, of equal size, forming a differential train.
The face wheel +, forming part of the upper bevel wheel 1, it is driven by the
train receiving its motion from the main shaft, and at the regular speed makes ono
revolution in five minutes.
The cylindrical wheel 5, forming part of the inner level wheel 3, and appertaining
to the chronometric train of wheels; it makes one revolution in five minutes.
The train of wheels and pinions 6, 7, 8, 9, 10, receiving motion from the wheel 5
and operating the escapement.
The escapement wheel 11 carrying tips as represented with its anchor 12 and
pendulum 13.
The 10 minutes wheel 14, and its pinion 15.
The 100 minutes wheel 16, and its pinion 17. The shaft of this wheel projects
beyond the dial plate C, and carries the indicating hand which turns on the dial of
the units.
The 1000 minutes wheel 18 and its pinion 19.
The 10,000 minutes wheel 20, the shaft of which also projects beyond the dial
plate and carries the hand over the dial of the hundreds.
A double system of wheels 22, 25, and ratchet wheels 21, 23, 24, 26, arranged on
the shaft of the differential train 1, 2, 3, in the interior of the casing. The two
pushing ratchet wheels 23 and 26 are fixed upon the shaft and their pawls are set
respectively on the wheels 22 and 25, forming with the latter two systems turning
loosely on the shaft. The pawls of the retaining ratchet wheels 21 and 24 are
arranged on the adjacent plates respectively. The teeth of the ratchet wheels 21,
24, and 23, 26, being cut in opposite directions it is evident that the wheels 22 and
25 can turn each only in one direction, opposite to each other, and that either of
the two will be held stationary when the other turns. The numbers of teeth are
so calculated that when the motor revolves at the normal speed the bevel wheels
1, 2, turn with equal velocity, in which case the shaft of the differential train will
remain stationary, but as soon as a difference in the velocities is produced, the
shaft will commence to turn, causing the corresponding wheel of maximum or
minimum speed to follow and leaving the other stationary.
The wheel 27 of the units of revolutions in excess, and its pinion 28. The shaft
of this wheel extends outward, and carries the hand indicating the units.
The wheel 29 of thousands of revolutions in excess, and its pinions 30.
The wheel 31 of 10,000 revolutions in excess. Its shaft extends also outward, and
carries the hand indicating the hundreds.
The wheel 32 of units of revolutions missing, and its pinion 33. Its shaft extends
outward, and carries the hand indicating the units.
The wheel 34 of thousands of revolutions missing, and its pinion 35.

page_text: The wheel 36 of 10,000 of revolutions missing, with its projecting shaft carrying
the hand which indicates the hundreds.
All the hands are held on their respective shafts merely by friction to admit of
their being set back to zero whenever desired.
The parts contained in the small casing are the following:-
The shaft 37 receiving its motion from the main shaft of the continuous indicator,
and carrying between the plates a pinion 38.
An intermediate wheel 39 gearing into 38, and carrying itself a pinion 40.
The wheel of 41 gearing into the pinion 40. Its shaft carries exterior to the
casing a pinion 42 gearing into the face wheel 4.
The wheel 43 formed in one piece with the wheel 41.
The wheel 44 gearing into the wheel 43, and serving to wind up the spring.
This wheel is loose on its shaft 45, and is constantly pushed against a shoulder on
the latter by a spiral spring 46. It carries a pin 47 projecting laterally from its
interior faco. This finger pushes one of the four pins c, c, set in the winding
shaft 45.
The spring casing 48, lantern 49, and nut 50, composing a differential system
analogous to the one described with reference to the indicator. The nut 50 carries
exterior to the lantern 49 two symmetrically placed arms 51, 52, each of which sup-
ports a roller 53, 54, turning on studs. These two rollers are constantly in contact
with the winding wheel 44.
The cover 55 of the casing 48 is formed with a sleeve 56, on the end of which is
fixed a bevel wheel 57 gearing into a similar one 58, the shaft of which latter carries
a pinion 59 gearing into the wheel 5.
The bridge 60 of the shaft 45.
The effects of these different arrangements is as follows:-The division of the
wheels being so calculated that at the smallest rate of speed the spring in the
casing 48 is wound up to exactly the amount necessary for the operating of
the escapement, an excess of winding up will be produced as soon as the speed
increases, whereby the nut 50 will be caused to advance, as has been explained with
reference to the indicator; the winding wheel 44 will therefore be pushed pro-
gressively by the rollers 53, 54, and the finger 47 will finally become disengaged
from the pin with which it has been in contact. At the moment when this dis-
engaging takes place, the shaft 45 will then under the influence of the spring, which
then is no longer restrained, rapidly turn back, the nut 50 will naturally retreat,
and the wheel 44 pushed by its spiral spring 46 will again engage its finger 47 with
the following pin, and so on. This automatic unwinding will consequently prevent
the spring from obtaining a larger tension than is desirable, because it will cause
said spring to reduce its tension in the same ratio in which it is produced.
It may be added here that this system solves the problem of a chronometric train
operated regularly by a motor having an irregular movement, and that this fact
renders the system applicable for a great number of other purposes.
I claim as my Invention with reference to Figures 1-5 inclusive,―
First. A continuous speed indicator which operates by bringing automatically and
constantly the speed of a chronometric train in accordance with the speed of a motor
by means of a pendulum of variable length.
Second. The method of varying the length of the pendulum by means of a
differential system of any suitable character.
Third. The differential screw system P, b, C, e, f, O, V, and the mechanism
j, K, u, u¹, u³, X, J, for raising and lowering the pendulum weight.
Fourth. The cinematic dispositions admitting of an equal division of the dial,
consisting in the relative lengths and positions of the levers X, Y, Z, and with
reference to Figures 6-8 inclusive.
Fifth. The general disposition of the differential counting machine, and more
particularly the mechanism for unwinding the spring composed of the shaft 45, with

page_text: its pins c, nut 50, arms 51, 52, rollers 53, 54, wheel 44, with its finger 47, and casing
48 with its spring.
Sixth. The system of the wheels 22, 25, with the ratchet wheels 23, 26, fixed
thereto, and the ratchet wheels 21, 24, fixed to the shaft and their respective pawls,
substantially as shown and described, and for the purposes set forth.
In witness whereof, I, the said Auguste Alfred Lebreton, have hereunto set
my hand and seal, this Sixth day of April, in the year of our Lord One
thousand eight hundred and seventy-nine.
Witness,
D. H. BRANDON,
1, Rue Laffitte,
Paris.
A. LEBRETON. (L.S.)