CERTAIN IMPROVEMENTS IN MACHINERY AND APPARATUS FOR MEASURING AND REGULATING THE WORKING OF ENGINES
Year: 1851

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JEAN MARIE
TAURINES, of Paris, in the Republic of France, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent under the Great Seal of the United Kingdom of Great Britain and
Ireland, bearing date at Westminster, this Sixteenth day of January, in the
fourteenth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Jean Marie Taurines, Her especial license,
sole privilege and authority, that I, the said Jean Marie Taurines, my exors,
admors, and assigns, and such others as I, the said Jean Marie Taurines, my
exors, adñiors, and 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, within the Islands of Jersey,
Guernsey, Alderney, Sark, and Man, and also within Her Majesty's Colonies
and Plantations abroad, my Invention of "CERTAIN IMPROVEMENTS IN MACHINERY
AND APPARATUS FOR MEASURING AND REGULATING THE WORKING OF ENGINES;" in
which said Letters Patent there is contained a proviso obliging me, the said
Jean Marie Taurines, by an instrument in writing under my hand and seal,
particularly to describe and ascertain the nature of my said Invention, and
in what manner the same is to be performed, and to cause the same to be
enrolled in Her 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 annear.

page_text: NOW KNOW YE, that in compliance with the said proviso I, the said
Jean Marie Taurines, do hereby declare that the nature of my said Inven-
tion, and the manner in which the same is to be performed, are described and
ascertained by the Drawing hereunto annexed, and forming part thereof, and
the words following, that is to say :-
DYNAMOMETER OF ROTATION WITH INSTANTANEOUS MODERATOR.-The object
of this apparatus is to measure the horse power transmitted to turning shafts.
It can be applied to screw or paddle boats as well as to stationary engines.
For these last it may serve also as instantaneous governor or regulator. The
shape of this apparatus varies according to the machine to which it is to be
applied; but in every case it has two principal features, namely, the dynamo-
metric springs, and certain mechanism for transmission which I term multiplyer.
The dynamometric springs are arranged as the arc of a circle, and have their
extremities fitted into the arms of the power and resistance, and transmit the
force of one to the other. They may have a fixed width, or this width may
be changed as required. The thickness is unavoidably variable-from one part
to the other. It is at its maximum at the parts where the springs fit into the
arms. It afterwards gradually diminishes for about one third of its length
from each end until it is not more than a few millimetres thick. It increases
again in thickness towards the centre, though weaker than in the other part.
The two halves of the springs are quite similar to each other. There are
always two springs, and more, if needed. The action of the force bends the
springs, and brings their centres near. It is by this bending or flexure that I
measure the intensity of the force or power. The strength and flexibility of
the springs depend on the angle, and the width and thickness of the slot. To
these springs is adapted what is called a multiplier, the purpose of this being,
first to transmit without play, without friction and wear, excepting, however,
for the functions of the regulator, the flexure of the springs on the turning
shaft; secondly, to considerably increase it, so as to have a greater degree of
precision in the results obtained; thirdly, to rectify any swerving from the
proper proportion to be kept between the flexures and the pressure. In my
Specification I will describe three kinds of multipliers. Sheets 1, 2, 3, 4,
represent the different modes of application of this mechanism to screw or
paddle boats, as well as to land machines. Sheet 3 relates to the dynamo-
meter used especially as regulator. Sheet 1 represents an apparatus con-
structed to show the mode of action of the different pieces constituting the
apparatus; it at the same time exemplifies its application to screw vessels.
The dynamometer is placed on the shaft of the screw. Fig. 1 of Sheet 1

page_text: represents a front elevation of the apparatus, Figure 2 is a plan, and Figure 3
a side elevation. A is the driving shaft fitted with a trunnion which rests in
an aperture made in the extremity of the shaft B, to which motion is to be
communicated. C, C, are arms fixed on the bearing of their respective shafts.
These arins are set at right angles in the Drawing; but this angle may be varied
These arms are terminated by square heads a pierced through their centre, as
at b, in Figure 1, to receive the ends of the dynamometric springs, and at c
perpendicularly to the opening b, to admit the retaining bolts of the springs.
D, D, dynamometric springs curved in the form of the arc of a cercle, concen-
tric with the shaft of a radius of ten inches, and of an angle of 80 degrees
(see Drawing, Figure 5). The blue line a¹, a¹, indicates the centre line.
The width increases in proportion of 1 to 2, and proportionally to the length
of the arc from the fixed points to the middle of the spring. The thickness is
equally variable. The parts enclosed in the heads of the arms are half an inch
thick, and are mortised so as to be held by the retaining bolts d at the fixed
points. The thickness is of a quarter of an inch (Figure 5), and diminishes
to the parts intersected by the blue line b', 6', where it is no more than one
twenty-fifth of an inch thick. It increases then very gradually to the centre
of the spring, where it is of about one eighth of an inch. A projection is left
in the middle to the extent of a quarter of an inch so as to facilitate the
joining of the spring with the parts above described. When the spring bends
the radius of the part beyond the blue line, that is to say, from the fixed points,
it diminishes. This decrease varies from one point to the other, so that it is
null at the point of the least thickness. At this part there is no flexure.
Beyond this point the radius of the curve increases in a variable manner to
the centre. E, E, are cross beams having at the middle eyes e, e, to receive
the bolts ff. A groove is made in the interior to allow the middle bend
of the spring to enter. The ends of the cross beams are slotted at h, h, and
I, I, for receiving the multiplying springs, and their retaining bolts m, m; each
cross beam is connected with the dynamometric spring by the bolts f, f, which
pass through the piece 9, g, in the spring. A proper tightening of the nuts
gives to the apparatus the necessary solidity. F, F, are multiplying springs
curved to the form of the arc of a cercle of a radius of seventeen inches, and
of an angle of seventy degrees, constructed after the same principle as the
dynamometric springs. The extremities, instead of continuing the arc of the
circle, are bent according to the direction of the chord of the arc. They have
a mortise, and are joined with the ends of the cross beams in the same manner
as the dynamometric springs are joined with the extremities of the arms.
Their width is one inch and a half at the bearing points, and an inch and a

page_text: quarter at the thinnest part. It afterwards increases to the middle, where it
is an inch and a half thick. The thickness is one eighth of an inch at the
bearing points, and one twenty-fourth of an inch in the part which does not
bend; it is about one sixteenth of an inch in the middle; there is in the
middle a portion of a quarter of an inch, where the thickness is greater, and
is pierced with two holes to carry the indicating springs. In the working of
the apparatus the multiplying springs do not lengthen, but, on the contrary,
shorten. The parts comprised between the bearing points and the part of the
least thickness experience an increase in the radius of the curve, and, on the
contrary, a diminution takes place in the central part. I, I, are indicating
springs, consisting of two steel bars curved in the form of the arc of a circle,
and fastened by screws to the hinges H, H. The hinge b, b, is bolted on to
the middle of the of the multiplying spring. A pin u, u, unites the two
hinges, and must be adjusted in such manner as to allow no slackening. The
middle of these springs carries a disc J, J, divided in two parts united by
screws (the hinge may be replaced by elastic fastenings, which will be described
in reference to the dynamometer Number 2. To this disc may be adapted
several very simple mechanisms to conduct, in a parallel manner to the shaft, the
pencil intended to trace the curve of the flexures, by aid of which is calculated
the amount of work transmitted by the springs to the resisting shaft, the work
done during a greater or less time. To graduate the springs the apparatus is
set upon a frame, which allows the resisting shaft to be fixed firmly on it. On
the driving shaft is fitted a lever of a sufficient length, at the extremity of
which are placed different weights. With a lever arm of one foot four inches,
and a load of about 360 pounds for this small apparatus, the points x, y, of
the arms widen parallel to the direction of the chorde of the springs of one
eighth of an inch, Figure 5. The centres of the dynamometric springs
approach fifty feet, the multiplying springs deviate in their middle one inch
and a half, and the edge of the disc coincides with the blue line z, moving in
the direction of the axis about one inch three quarters. Thus is determined
the relation that exists between the distance gone over by the disc or the
radius, and the weight acting at the end of the lever. It is evident that when
the apparatus is working the motive power is equal to the weight capable of
displacing the disc, as already described. Then, by calculating the medium
of flexure of the indicating springs, by aid of the curve obtained during the
operation, we know the amount of the power, and from it is to be deducted
the quantity of work attained by one turn. It will then be easy to ascertain
the horse power of the machine, if the length of time be also observed. On
the disc, or more simply on the indicating springs, is fixed, by screws, a copper

page_text: cylinder of two parts united by screws.
It is terminated on the other side by
a flange q, with a V groove intended to receive the collar O. This collar is in
two parts, united by bolts with nuts, and embraces the V groove. It bears
two arms P, P, fixed at the ends by bolts. The ends have rollers R, which
run on guides Q, Q, placed outside the apparatus. In this manner the collar
does not receive a rotatory motion; it is only drawn in the direction of the
flexure by the cylinder. N, the two pencil-holders R, R", serving to trace,
one the curve of the flexures, the other line of zero. The first is firmly
attached on to the upper part of the collar at S, the second on a piece outside
the apparatus. When the springs have no band, the centres of the sockets of
the two pencil-holders are ou a same line, perpendicular to the shaft. A small
sole plate s¹ supports the guides and the pencil-holder R". T is a copper
cylinder for paper, made of two parts, having at each end hinged collars H,
and uniting fastenings u, u; the paper is held on the cylinder by small
springs; it is kept, by gentle friction, on a shoulder in two parts slightly
conical, and attached on the shaft by small flat-headed screws. The cylinder
T is furnished with paper detached from the apparatus. It is afterwards
opened, and then placed on the shaft, and after having been closed is pushed
on the shoulder, which, by the tightening, carries it round. Only one pencil
must be used, which is at first placed in the pencil-holder R", for the line of
zero, and to cause the point of the pencil, in case of eccentricity, to present
itself always in the same manner. The pencil has a feather which slides
along the grooves, fitting in the interior of the sockets of the pencil-holder.
This apparatus is only applicable in cases where the machine is directly
attached to the shaft of the helix. The curve of a piston stroke is obtained
as with Watt's Indicator; known means can, however, be employed to pro-
duce several curves. With the system above described we can measure the
greatest power of the screw machines. Thus, for instance, for a steam boat of
650-horse power,
it is sufficient to take springs of two inches wide, of five
eighths of an inch thick at the bearing points, of an angle of forty degrees,
and of two feet six inches radius. In this case two pairs of springs must be
used and placed side by side of one another; the instrument will then bear a
load of more than twenty-two thousand pounds with three feet four inches of
lever arm, and would have but to measure a medium power of about 16,000
pounds. In calculating the width, thickness, and radius, it is always possible to
increase the power of the dynamometer by the diminution of the angle, because
the moment of resistance of the springs is thus weakened. The transverse
flexure decreases, it is true; but whilst for this flexure forty degrees is only
the third of that corresponding to one hundred and twenty degrees, the

page_text: moment of resistance is, for forty degrees, ten times less than for one hundred and
twenty. The multiplier gives always the facility of making the flexure greater
for observations. It is in varying the angle that this can be accomplished.
Thus, for instance, the multiplying springs of the apparatus above described
having seventy-degrees, trebling the transversal flexures of the dynamometric
springs with an angle of forty degrees. The flexure is then made five-fold
without motion or friction. Even four springs may be secured on the same
arm, two in the direction of the width, and two in the direction of the thick-
ness, and thus four pairs may be used. The arrangement of the springs, in
the arc of cercle, is convenient for the arrangement of the pieces, if it is
required to have springs of a thickness greater than that given by a good
temper. The drawing of the thickness of the spring is executed as if the
spring were to be made of one piece. It is divided into two parts in making
an arc of a cercle pass in the middle of the thicknesses. Two springs are
afterwards made similar to those two parts, and after having tempered them
separately, are made to coincide perfectly in uniting them in the middle to
the parts of the least thickness, and at the extremities; after having taken
care to leave in these parts sufficient thickness for the joining of the pieces;
such springs, having elevated angles, would give considerable flexures. It is
thus possible in all cases to construct at will, for a same pressure, dynamo-
metric springs of great or small flexure, the facility of uniting several pairs by
joining springs of a thickness superior to that which is in use for the temper,
and especially the reduction of the angle of the spring; on the other hand,
the power of the multiplyer to increase considerably and in an invariable
manner the transversal flexure of the dynamometric springs. All these means
facilitate the measurement of rotary power, greatly surpassing that of the
greatest marine engines.
DYNAMOMETER NUMBER 2.-Figure 1, elevation; Figure 2, side view;
Figure, 3, plan; Figure 4, dynamometric springs, with two modes of joining;
Figure 5, details. Sheet 2 (scale of one fifth in the Figures 1, 2, 3, and of
one half for the Figure 4) represents the manner of fixing the dynamometer
in stationary engines; it may be fixed on the driving shaft or on the transmiş-
sion shaft, in both cases the power being communicated by gearing or a pulley.
'The process consists in making loose the wheel or pulley, by taking away the
tightening bolts. In the Figure it is in the transmission shaft A that the
instrument is attached, and the motion of the machine is communicated to the
system by a band passing over the pulley B, which for the dynamometer,
Figure 1 in the Sheet, is already constructed, is eight feet nine inches in

page_text: diameter. This pulley rests on the shaft by means of a hollow brass collar,
but this particular arrangement is intended to lessen the friction, and is not
indispensible. The pulley has a rim c of cast iron for the dynamometer, figured
in the Plan, but which may in general form a distinct piece, and which is then
applied against the pulley by bolts, as will be seen in the description of the
instantaneous regulator, Sheet 3. The rim is pierced with square holes, in
which are fitted the two heads D, and to these the extremities of the springs
are fitted, and act as arms of resistance. On the shaft is set the double lever
arm E, divided into two parts, united by bolts; and between the heads D, E,
are interposed the dynamometric springs F, in the same manner as in the dyna-
mometer Number 1. Each of these springs is in two pieces attached in the
centre at G by a tightening bolt. A strop H, fitted on the rim, serves to
regulate the extent of the flexure, and to hinder the springs from being forced
when they arrive at the maximum of tension. The multiplyer of this
dynamometer Number 1 is composed of cross beams I, fixed on the boss of
the centres of the springs, as will hereafter be explained. At the extremities
of these cross beams are jointed rigid rods with forks J, J, J, J, which act the
same as multiplying springs by reason of their inclination. When the centres
of the dynamometric springs which approach to one inch three eighths, the
pieces L, which unite the ends of the rods, are about two inches three quarters
distant. The mode of joining employed, though suiting the same purpose as
the inner and outer hinges, has not the same inconveniences. It consists
of three or four clock-spring blades superposed, strongly clasping the two ends
at the extremities of the rods and of the cross beams. The part that is flexible
is but half an inch long. See this kind of joint in Figure 5. Two other
rods M are joined by the same method to the pieces L and to the disc N. For
a transverse flexure of the dynamometric springs of one inch three eighths of
an inch, the disc moves three inches towards the pulley. Against the disc is
fixed a cylinder O, concentric with the shaft and supported by light rollers, and
bearing at each extremity a projection to which is fitted a collar P, with arms,
joined by cross heads Q, having rollers rolling on guides on the right. These
collars, as the dynamometer Number 1, do not participate in the movement of
rotation of the system, but have the longitudinal motion of the cylinder. The
cross head on the left Q carries the pencil-holder intended to trace the curves
of flexure on the paper cylinder R, set in motion by the gearing S. The
worm T and the wheel v are all disposed in such manner that the drum R
makes a turn for each fifteen revolutions of the shaft. The effect of the rod
multiplyer, with the polygonal contour, depends especially on the angles of the
different sides of this polygon, and of the length of the bridles M attached

page_text: to the cylinder. The angles are made to vary in the following manner :-Each
cross beam I has in its centre four slides a, which can slide easily on the boss
of the centres of the springs when the screws which retain them are loosened.
The length of the rods M is reduced by a mechanism similar to that of the
reducing compass. The facility of altering at will these two elements gives the
facility of properly regulating the multiplyer, to obtain first the proportion of the
flexures to the loads. The angles determined, the bridles M are lengthened or
shortened a little, accordingly as the flexures increases too rapidly or too slowly.
In the Figure the cross beams are one inch distant from their boss, the slides
may then slide to that extent. The length of the bridles M is such that the
distance from the centre of their small fastening springs d of the cylinder, to
the plane surface of the boss of the shaft, is of of three inches three eighths.
The polygonal multiplyer has the advantage of lengthening the graduated scales
when the pressure diminishes, which allows of the use of the same instrument to
measure great and small pressure. The multiplyer forms the polygonal contour
of the red lines e. The bridles, M are shortened, so as to bring the small
tightening springs d on the red line S, horizontal projection. By this disposi-
tion, if one has, for instance, with the scale of great forces, three quarters of an
inch for the load of four hundred pounds, to the circumference of the pulley of
four feet three quarters of an inch of radius, the new scale will give half more,
and thus a flexure equal to one inch.
D, which each
PORTABLE DYNAMOMETER, WITH INSTANTANEOUS REGULATOR.-Sheet 3 repre-
sents the manner of fixing the dynamometer on a wheel or pulley B, previously
made loose. In the Plan it is on the driving shaft A that the apparatus is
fitted up. It might also be placed on a transmission shaft, as has been seen
for the dynamometer Number 2. The rim, divided in two parts c, c, is
applied against the pulley; its extremities are united by bridles
clasp one of the portions of the pulley (see the section x, y). The rim bears
bears, besides, against the other edge, by the help of bolts, and of two segments
E placed behind the pulley (see section x, y). This rim, pierced with two holes,
receives two square heads F, which represent the resisting power. On the
shaft A is adapted the double lever arm G, divided in two parts, united by
bolts. The springs H are slotted, as in the preceding dynamometers, in the
arms of the power shaft and of the resisting stops. They are divided
into two parts, and are joined in the centre by the piece I, as in the dynamo-
meter Number 2. The multiplyer of this apparatus is particularly suited for
acting as an instantaneous regulator, not requiring in the play of its different
parts the same precision as for dynamometric observations, differing in this

page_text: respect from the two previously described multiplyers; it is composed of two
rods L, having at each end forks M. These rods are attached by means of
screws with points N, furnished with counter nuts, first, to the piece J, fastened
by screws on the piece I; secondly, to the disc, which has a cylinder similar to
that of the dynamometer Number 2. As for this last, there is collar with arms,
guides, and rollers, not participating in the movement of rotation of the system,
but yielding to the traverse of the cylinder along the shaft. This movement
takes place in a direction opposite to that of the dynamometers Number 1 and
Number 2. The cylinder does not advance in proportion to the load. The
differences of proportion are made to coincide in the following manner :-On
the side of the shaft A is placed a bent lever P, Q, R, which is made to oscil-
late round the point Q as its centre. The arm P is perpendicular to the shaft ;
the arm R is terminated by a slide inclined about thirty-five degrees on the
shaft, and slightly curved; it receives a roller or button T, placed on the collar
of the cylinder. The movement of the extremity of the arm P, considered as
parallel to the shaft, is thus always proportional to the load, when a proper
inclination and curve is made for the arms R by help of ropes or of rods; the
extremity of the arm P acts by the intermediate curved levers on the valve O,
which regulates the entrance of the motive fluid in the receiver (see Figure 4).
The system is applicable to steam engines and hydraulic wheels. When the
machine works regularly there is an equilibrium between the moving and
the resisting forces; in this case the springs preserve the same flexure, or at
least oscillate equally for the periodical movements. If this equilibrium
bappens to be momentarily disturbed, the springs tighten or loosen more in
correspondance with the loss of equilibrium. If the power be greater than
the resistance, in which case the motion has a tendency to be accelerated, the
springs instantly unbend, and their centres widening, the cylinder will run
from right to left, and the valve which it conducts will diminish the opening,
the power will thus become equal to the resistance, and the speed will remain
the same.
In the contrary case, when the moving power is weaker than the
resisting forces, the motion cannot slacken, because the springs bend, thus
drawing close the centres of the springs, and setting in motion the collar from
left to right, and the valve then widens the opening. When the springs have
the strongest bend, the cylinder is at the extremity of its course on the right;
the valve is then wide open. When the force is null the cylinder is on the left,
at the end of its course; the valve is then entirely closed. Thus the width of
the opening is always in correspondance with the power necessary to be produce
to overcome the resistance of the machine. This regulator prevents the irregu-
larities of speed, whilst the existing ones in use only check them. The

page_text: apparatus may always serve also as dynamometer, by placing a pencil-holder at
the extremity of the arm P, and a paper cylinder V as for the dynamometer
Number 2, which will give indications sufficiently exact for practise.
MARINE DYNAMOMETER.-In Sheet 4 the scale is one fifth for all the Figures,
except Figures 6, 7, and 8, which are on the scale of one half. Figure 1 is an
elevation or front view of the apparatus; Figure 2 is a horizontal section of the
dynamometer, following the line of the centres of the eye of the crank and of
the shaft; Figure 3 is an elevation, and Figure 4 a horizontal projection,
of the upper cross beam; Figure 5 is a horizontal projection of the lower cross
beam; Figure 6 exhibits the concentric springs, with the multiplyer; Figure 7
shews the convex springs, with the multiplyer; Figure 8 is the support, with
the slide of the upper cross beam; Figure 9 is a section of the handle and
horizontal projection of the cylinder, and of the bridles; Figure 10 shews the
multiplying springs, with the bridles of the cylinder; Figure 11 is a vertical
section of the crank and pin, by the middle of the dynamometer springs;
Figure 12 is a vertical section of the same pieces, with another kind of slot.
As to the dynamometer of paddle boats, the arm of the power is represented by
the extremity of the pin A of the intermediate crank, and that of the resistance
by the exterior crank B. To fix the apparatus, the crank pin is first taken off,
and at its extremity is formed a hollow, such as is indicated in the Figures 1 and 2.
There is likewise made in the head of the exterior crank two rectangular
openings a, a, Figures 1 and 2; and a small circular opening b, Figures 2
and 3. And after having put aside the two cranks, in such manner that the
intermediate one be in advance sixty degrees, the button pin is put back in its
place. It is likewise necessary to take away the two steel pieces which are in
the eye of the exterior crank, and replace them by two other pieces; as is seen
in Figures 1 and 8, strictly one can be preserved. A piece d is afterwards
adapted to the part that is sloped out for the working of the steel pieces, so
that the contour may be complete. It is these preliminary dispositions that
that the steam engine is capable of receiving the dynamometric apparatus
above described, and of which the Drawing shows the machine at the larboard
of a paddle boat of three hundred and twenty horse power. To understand the
front view, we must suppose that one is turned on the side of the wheel. Thus,
the cylinder is behind, whilst, for the plans of the preceding dynamometers, it
is in the front.

page_text: which two, c, c, are concentric to the end shaft, and the two others c', c¹, are
eccentric, and turning their convexity towards the shaft. The two first placed
side by side, Figure 2, are perfectly alike; they have an angle of forty-three
degrees, and the following dimensions,-radius, five eighths of an inch; chord,
one foot ten inches; shaft, two inches. The two other springs are equally
like to one another, but different from the concentric springs; they have an
angle of forty degrees and the following dimensions,-radius, two feet six
inches common width, two inches thickness; at the slotting, five inches three
eighths; chord, one foot eight inches and three quarters; shaft, two inches.
The chords of these arcs, as may be seen, are not equal, but their extremities
are situated on the same radii from the centre of the crank. Strictly, chords
of equal lengths might be used, but in the mode of action of the springs, which
is herein-after described, the load would be less equally divided between the
two systems. The ends of the springs on the side of the pin are straightened
parallel to the chord, and slotted in a piece of iron D, in the shape of a stirrup.
Between the upper and lower springs are forced keys e, serving to make the
springs bear on all parts of the slots. These springs and these keys are
pierced with holes in which are passed retaining bolts f. The extremity of
the pin, previously sloped out and slightly convex, as shown in Figure 2, is
clasped by the stirrup braces g, fastened by screws in the interior of the stirrup,
serve to reduce the friction. On the side of the crank the ends of the springs
are dovetailed, h, in the width; their thickness increases likewise gradually
towards the extremities; they are held by two cast-iron discs E, in which are
lodged their extremities, and pierced with a rectangular opening and four
circular holes; a key and wedge i, and the pin j, as well as four bolts, make
the discs coincide. The same pin in pressing the springs makes their extre-
mities fit closely to the sides of the cavities, and prevents all play. The
contour of the discs is slightly convex, as in the pin. The principal flexure is
the drawing near the centres of the upper and lower springs. The shaft, being
exposed to irregularities of position, may turn in an excentric manner in
respect to the intermediate shaft. It results that in the rotary motion of the
system, the distances from the centres of dynamomentric springs to the axis of
the outside shaft are subjected to slight variations. The preceding dispositions
have for their object the guarding from this influence the centres of the
springs. If, during a turn, the exterior crank rises or falls, and that it slightly
inclines with respect to the shaft, the discs and the pins, being rather convex,
are susceptible of each a double occillatory motion with respect to the eye of
the crank and the stirrup, as in the suspension of chords. The play existing
for the stirrup and the discs is merely to render the width of the centres of

page_text: the springs more independent of the irregularities of the motion of the shaft
of the wheels. The mode of action of dynamometric springs is complex.
The springs would act completely on the crank by means of traction, that is
to say, as an extending rod jointed to the arms of the power and of the resis-.
tance, if the friction of the stirrup and of the discs on the pin and eye of the
crank were null; for in this case the pin and the disc might turn freely from
the quantity necessary for the lengthening the springs, but by this friction these
two pieces are hindered in the angular movement, and there is thus a portion
of the force which does not produce a movement. The springs act then in
two ways, first, by way of traction for all the force overcoming the friction;
secondly, and for that which is taken up by the friction, they act as if they
were invariably fixed in the pins and the eye of the crank. The springs are
constructed in such manner that, all things being equal besides, the transversal
flexure is the same in these two modes of action, from which it results, that
the friction cannot alter the accuracy of the results. If but very slight
irregularities only have to be avoided, we might, as indicated in Figures 12
and 12bis, slot the springs in the pin itself, in which a suitable cavity might be
made. In either cases the springs are calculated to resist alteration of
elasticity to a pressure of twenty thousand pounds, with three feet four inches
of lever arm, and give a transverse flexure of about three quarters of an inch.
To prevent the springs from being forced and produce a retrograde motion of
the machine without compressing too much the springs, the pin has in front
a collar with a rod and a block placed in the eye, and also rounded in the part
in contact with the crank; between the edges of the collar are interposed two
plates, of which thickness is regulated so as to have the necessary play for the
lengthening of the springs.
MULTIPLYER. The multiplyer is of the same kind as in the dynamometer
Number 1. It can produce a fourfold or greater transverse flexure of the
dynamometric springs. Its cross beams F, F, are composed of two plates
e, e, e, e', of sheet iron, bound together by transoms. For the upper cross
beam F, the plates 1, 1, are sufficiently distant to guard the arms of the crank.
The transoms of the extremities m, m', are pierced with two rectangular
openings n, n, n', n', in which are slotted the multiplying springs G, G, in the
number of four, see Figure 4, for the top cross beam, and Figure 5 for the
lower one.
The cross beams are firmly attached to the centres of the dyna-
mometric springs in the following manner :-The upper cross beam bears in
its centre a transom which receives the collars of both rods p, p, to which the
ends join by plates q, q', placed above and under the centre of the concentric
springs, Figure 6. The flexure of the convex springs is transmitted to the

page_text: lower cross beam by the intermediate pieces r, and of the links s, s¹. That
on the left s is slightly curved to let free the arm of the crank, and is termi-
nated by an eye of the interior piece, Figure 7, which works in the exterior
piece of a plate t, situated under the convex springs; this last has the exterior
for the other strap, which in this part has the form of a fork. The plate t is
fixed against the springs by bolts with conical heads, and passing through the
springs pierced with holes, and having for this purpose an increase of thickness
in the centre. All these hinges are united by a bolt with a nut; the
tightening hinders play; it is the same for the joining of the different pieces
which bind the lower springs to their cross beam. The whole must form one
firm and unalterable apparatus. By the help of the preceding arrangements,
when the dynamometric springs approach three quarters of an inch towards
the centres, the multiplying springs widen in their centres to about three
inches and a half, so as to maintain the multiplyer in the different positions,
especially in the horizontal position. The transom u of the middle of the lower.
cross beam.is terminated by pivots which slide with little friction in the fixed
grooves against the boss of the crank. For the same purpose there is made
in the transom of the centre of the upper cross beam a square piece, which
can freely move in the groove belonging to the transom V, which connects the
straps (Figure 8).
CYLINDER. CARRIAGE (Figure 9).-The cylinder consists of a brass disc H,
with a V groove, and composed of two parts which join by means of bridles
bolted on each side. Between these bridles are set pieces Y, intended to
form a groove in the V groove of the pulleys Z, attached to the boss of the
crank. The two parts of the cylinder can be bound together from the opposite
side by plates and flat-headed screws; they are not shewn in the Drawing.
The disc rests on four rollers z, all placed on the same side. This disc, as
indicated in Figure 9, is attached to a system of bridles or rods joined by
spring connections, and transmitting completely the flexure of the multiplyer,
all as in the dynamometer Number 2, with this difference, that the rods I, J,
have additional connections a¹, a" which work, when, by reason of the irregular
lifting of the shaft of the wheel, or by any other cause, the multiplyer happens
to become excentric in its rotary movements. For the absence of flexure the
edge of the disc is at three quarters of an inch from the edge of the rests b, b,
it goes from it as the springs bend. The power of the apparatus is increased
by the means indicated at the end of the description of the .dynamometer
Number 1. The apparatus will answer to test any degree of power, and
moreover, it will only be necessary to make on the head of the crank the
openings of a size suitable for the proper working of the apparatus. The

page_text: dynamometer Number 4 can, if required, be in certain cases, and with
some modifications, applied to other cranks than those of steam vessels.
Having now described my Invention, and the manner in which the same
may be carried into effect, I may observe that I do not confine myself to the
precise arrangement described, or to the figures expressing the dimensions of
the several apparatus above described, as they must evidently vary according
to the power of the machines constructed. But I claim,-
First, the arrangement, construction, and system of slotting the dynamo-
metric springs for the purpose of measuring varies degrees of power.
Secondly, the peculiar arrangement of the mechanism of transmission or
multipliers, as hercin-before described.
Thirdly, the adaptation and use of the cylinder carriage for obtaining the
traverse of the flexure on the shaft.
Fourthly, the application and use of the dynamometric mechanism to screw
steamers, paddle boats, and stationary engines.
Fifthly, the peculiar arrangement of an instantaneous regulator, as herein-
before described.
In witness whereof, I, the said Jean Marie Taurines, have hereunto set
my hand and seal, this Sixteenth day of July, in the year of our Lord
One thousand eight hundred and fifty-one.
Enrolled the Sixteenth day of July, in the year of our Lord One thousand
eight hundred and fifty-one.