New or Improved Variable Speed Mechanism for Transmitting Power.
Year: 1899

page_text: Date of Application, 5th Sept., 1899-Accepted, 4th Nov., 1899
COMPLETE SPECIFICATION.
New or Improved Variable Speed Mechanism for Transmitting
Power.
I, HENRY BIRKBECK, Chartered Patent Agent, of the Firm of Tongue &
Birkbeck, of Southampton Buildings, Chancery Lane, London, do hereby
declare the nature of this invention (a communication to me from abroad by
The Dieterich Gear Company, a Corporation located and doing business at
52, Broadway, in the City of New York, Borough of Manhattan and State of
New York, U.S.A., Manufacturers) and in what manner the same is to be per-
formed to be particularly described and ascertained in and by the following
statement:-
This invention relates to improvements in power transmitters, and particu-
larly to a power-transmitting mechanism which is intended to receive power
at a substantially uniform speed and force and deliver the same at a speed and
force which may vary with variations in the resistance to be overcome.
The object of the invention is to provide a device by means of which a
source of uniform power may be advantageously used in driving mechanism
whose resistance may vary owing to variations in the load upon it, the speed of
the driven mechanism being reduced upon an increase of its resistance or load
and increased upon a reduction of such resistance or load.
it rotates
With this general object in view an apparatus embodying this invention com-
prises a revoluble mechanism interposed between the driving and driven
mechanisms and
which
axis about
so arranged that the
may be shifted with relation to the axes of rotation of the driving
and driven mechanisms, and two sets of devices one between the
driving mechanism and the intermediate mechanism and the other between
the latter and the driven mechanism by means of which the power from
the driving mechanism is transmitted to the intermediate mechanism and from
the latter to the driven mechanism, said transmitting devices being of such a
nature that they resolve the rotary motion delivered to them by the revoluble
driving mechanism into two resultants, one of which is rotary, while the other
is rectilineal, whereby the set of transmitting devices between the driving
mechanism and the intermediate mechanism will cause the rotation of said
intermediate mechanism and at the same time tend to shift the axis of said
intermediate mechanism, while the other set of transmitting devices between
the intermediate mechanism and the driven mechanism will cause the rotation
of the latter and will also tend to shift the axis of the intermediate mechanism
but in a direction opposite to that in which the first set of transmitting devices
tends to move said axis. Consequently, as long as the opposing rectilineal re-
sultants which are produced by the two sets of transmitting devices, are equal,
no shifting of the axis of the intermediate mechanism will occur, but when
one of the rectilineal resultants is greater than the other, the said axis of the
intermediate mechanism will be shifted with relation to the axes of the driving
and driven mechanism until equilibrium is established between the two opposing
resultants, this equilibrium being brought about by changes in the conditions

page_text: or positions of the two sets of transmitting devices, whereby one set of trans-
mitting devices becomes less effective in producing the rectilineal resultant and
the other set becomes more effective, the changes in the conditions or positions
of the transmitting devices being due to the shifting of the axis of the inter-
mediate mechanism.
What may be called toggle-transmitting devices are of particular advantage
for the transmitting mechanisms and by this term I desire to include any
mechanism or device arranged to transmit motion from the driving mechanism
to the intermediate mechanism and from the latter to the driven mechanism,
and which involve the fundamental principle of the well-known toggle-levers.
The invention consists furthermore in the details of construction and combi-
nation of parts which will first be described in connection with the accom-
panying drawings and then particularly pointed out in the claims.
Referring to the accompanying drawings:-
Fig. 1 is an elevation of the improved power transmitter, embodying one
part of the invention;
Fig. 2 is an end view, partly in section of the same;
Fig. 3 is also an end view, showing a modified arrangement;
Figs. 4 and 5, 6 and 7 are respectively side elevations and sections of an
apparatus embodying all the features of the invention;
Fig. 8 is a transverse sectional view of a bicycle driving gear provided with
the invention;
Fig. 9 is a detail sectional view, partly in elevation of the same;
Fig. 10 is a vertical transverse section, showing the transmitting mechanism
applied to the countershaft of a lathe or other machine.
Similar letters of reference indicate corresponding parts.
Referring to Figs. 1 and 2 of the drawings, o is a shaft revolved from any
suitable source of power, not shown. This shaft is provided with a disc d,
fixed to it in any suitable manner, the disc and shaft together being embraced
within the term driving or power-supplying mechanism.
a revoluble driven
Opposite to the said driving mechanism is located
mechanism, in this case comprising a driven shaft k and a disc d' fixed thereon
and suitably mounted to permit of rotation, the axis of rotation of said driven
mechanism preferably being in a line with the axis of rotation of the driving
mechanism.
Between the driving mechanism and the driven mechanism above described
is located a revoluble intermediate mechanism, comprising, in the present
instance, a pair of rings R4 R5 fixed to opposite ends of a shaft o', the axis of
rotation of the said intermediate mechanisin being movable or adjustable with
relation to the axes of the driving and driven mechanisms, which result may
be obtained by arranging and constructing the intermediate mechanism so that
its axis of rotation may be shifted with relation to the axes of the driving
and driven mechanisms, as for example, by mounting the shaft o¹ in a movable
arms F,
bearing, said bearing 1 being made movable by mounting it on
which are longitudinally movable in supports G.
In order to transmit motion from the driving mechanism to the intermediate
mechanism and from the latter to the driven mechanism, there are employed
suitable transmitting mechanisms, one mechanism between the driving
mechanism and the intermediate mechanism and the other between the latter
and the driven mechanism.
Each transmitting mechanism comprises two transmitting devices connected
to the intermediate mechanism in a manner to permit the adjustment or shifting
of the axis of the intermediate mechanism with relation to the axis of the
driving mechanism.
The transmitting devices shown in Figs. 1 and 2 consist of angularly-movable
arms, as shown at L1, L2 each mounted for rotation about an axis concentric
with the axis of rotation of the driving mechanism, as for example, by pro-

page_text: viding each arm with a hub or boss which is placed loosely on the shaft o.
The outer ends of the said arms L1, L2 are each provided with a slot, into each
of which slots enter pins I¹, 12, fixed on the ring R of the intermediate
mechanism.
Each transmitting device, furthermore, may be locked or connected to the
driving mechanism by means of a suitable locking device, such as the frictional
locking device shown in Figs. 1 and 2 which consists of a cam, as shown at cl, c³,
pivotally connected to the respective arm as indicated at t¹, t2.
These cams
are so arranged that when locked they bear against the periphery of the disc d,
and when unlocked they slide over or along said periphery.
The transmitting devices between the intermediate mechanism and the driven
mechanism, and the locking devices which lock the said transmitting devices
to the driven mechanism, are similar to those just described, the only difference
being that they are arranged in a reverse order.
The operation of the apparatus thus far described is as follows:-
When the shaft o is rotated by suitable means, its disc d is also rotated. If,
now, it be assumed that the axis of the intermediate mechanism, or in other
words, the axis of the shaft o', is concentric with the axis of the shaft o, the
rotation of the disc d, (which is supposed to be in the direction of the arrow,
Fig. 1) will cause the cams c¹, ², to lock the arms L1, L2, respectively to the
disc d, thus forcing said arms to rotate about the axis of the shaft o', thereby
also causing the ring, R, to be rotated about its axis, owing to the fact that
the outer ends of the arms L1, L2, are connected to the said ring R+. As the
rings R and R³ are fixed to the shaft o¹, the rotation of the ring R will cause
the rotation of the ring R5. The rotation of the latter will cause the
arms L3, L4, to be revolved about the axis of the driven shaft k, and owing to
the friction between the cams 3, 4, on the periphery of the disc d, the said
cams will be locked to said disc and hence the latter will be compelled to rotate
with the arms L3, L and the intermediate mechanism. It will be plain there-
fore that when the axis of the intermediate mechanism is concentric with the
axes of the driving and driven mechanisms, the driving mechanism will drive
the driven mechanism at the same speed as its own.
If now the axis of rotation of the intermediate mechanism be shifted so
that instead of being concentric with the axes of the driving and driven
mechanisms, it is eccentric therewith, a different operation will occur.
In order to simplify the description of this operation it becomes necessary
to designate and define two imaginary planes of reference.
These are as
follows:
The plane passing through the axis of the intermediate mechanism and
through the axis of the driving mechanism will be called the vertical plane,
the line in which it would cut Fig. 1 being indicated at y-y.
The plane coincident with the axis of the driving mechanism and at right
angles to the vertical plane will be called the horizontal plane, its intersection
with the plane of Fig. 2 being indicated in Fig. 1 by the liner.
Furthermore, in referring to these planes, it will be understood that that
side of the horizontal plane on which the axis of the intermediate mechanism
is located is above said horizontal plane, while the opposite side is below said
plane, said terms being in accordance with the showing in Fig. 1. It is to be
understood, however, that said terms are relative only and are to be considered
in that sense for if the axis of the driving mechanism is shifted to a vertical
position, the terms above" and below would not apply if used in their
usual sense.
66
66
With this explanation, the operation of the mechanism shown in Figs. 1
and 2 will be described.
Referring to Fig. 2, which shows the axis of the intermediate mechanism
eccentric to that of the driving mechanism, it will be found that the rotation
of the disc, d, in the direction of the arrow, Fig. 1, will cause the cam c¹ while

page_text: above the horizontal plane, to lock its arm L' to the said disc, and said arm
would cause the periphery of the ring R4 to rotate with the disc d at a peripheral
speed as much greater than the peripheral speed of the disc d as the distance
of the pin I from the axis of the shaft ol is greater than the distance of the
periphery of the disc d from the said axis of o¹.
As, however, all parts of the periphery of the ring, R, must revolve at the
same peripheral speed, the pin 1 below the horizontal plane will be revolved
about the axis of the shaft o at the same peripheral speed as the pin I, and
owing to its connection with the arm L2, will cause the latter, also to revolve
about the axis of the shaft o. But, owing to the eccentricity of the axis of
the intermediate mechanism the distance of the pin 12 (when below the hori-
zontal plane) from the axis of the arms L1, L2, is less than the distance of
the pin I, (when above the horizontal plane) from said axis. Therefore, as is
obvious, the cam on the arm L², will move as much faster than the cain e¹,
as the distance of the pin I from the axis of o is greater than the distance of
the pin I from the same axis. But since the cam c¹ is locked to the disc d
and therefore, travelling at the same peripheral speed as the periphery of said
disc, and since the cam is travelling at a greater peripheral speed than that
of the cam c', therefore the cam travels at a greater peripheral speed than
the periphery of the disc d. Hence, the friction between the cam and the
disc d will tend to keep said cam unlocked, the cam merely slipping along
the periphery of the disc d.
As the arm L' moves around its axis, from a position above the horizontal
plane (in which position it is shown in Fig. 1) to a position below the said
plane, its effective lever-arm, that is to say, the distance between its connec-
tion with the ring R and the axis of o becomes gradually less, while as the
arm L³ moves from the position below the horizontal plane (in which position
it appears in Fig. 1) to a position above said plane, its effective lever-arm
becomes greater. When the said arms L1, L2, lie with their respective points
of connection to the ring R in the horizontal plane, the effective leverages of
the arms L L2 are equal, and the cams c¹ 2 will travel at the same peripheral
speed, and, hence at this moment both cams will be locked to the disc d. But
as the effective leverage of the arm L¹ constantly grows less even after it
passes below the horizontal plane, its cam will commence to travel faster
than the periphery of the disc d and therefore will be unlocked, that is to say
will slip or slide over said periphery of the disc. And, furthermore, since the
effective leverage of the arm L will continue to increase after said arm has
passed above the horizontal plane its cam will no longer travel faster than
the periphery of the disc d and hence the latter will maintain the said cam in
its locked position, the said arm L2 thereby becoming the means for driving
the ring R while the arm L' then turns about the axis of the shaft o, without
doing any useful work until it has again passed above the horizontal plane.
In this way the arms L L alternately are locked to the driving mechanism,
and unlocked therefrom, thereby alternately acting to drive the ring R. In
other words, when a transmitting device is above the horizontal plane, it will
be locked to the disc d and will drive the intermediate mechanism, whereas
when it is below the horizontal plane, it will be unlocked from the disc d and
will be dragged around by the rotation of the intermediate mechanism until
it is again brought to its position for operation.
It is to be understood, however, that when more than two transmitting levers
are employed in each set of transmitting mechanisms, as for example, three
transmitting devices located at equal distances apart, as shown in Figs. 4 and 6,
and as will be referred to hereinafter, only that transmitting lever which is
nearest the vertical plane and above the horizontal plane will be locked to the
driving mechanism while all of the remaining transmitting levers will be
carried around by the revolution of the intermediate mechanism and will be
unlocked from the driving mechanism.

page_text: When only two transmitting levers are employed in each set of transmitting
mechanisms, as shown in Figs. 1 and 2, the intermediate mechanism is rotated
at a variable speed, varying from a minimum to a maximum, and then to a
minimum again, the first minimum-speed occurring when the transmitting
lever lies with its point of connection to the intermediate mechanism in the
horizontal plane and is moving in a direction to carry it above said plane. At
this time the angular velocity of the intermediate mechanism is just equal to
that of the driving mechanism.
As the said transmitting lever rises above the horizontal plane its angular
velocity remains the same, while the angular velocity of the intermediate
mechanism gradually increases, until the point of connection between the said
transmitting lever and the intermediate mechanism lies in the vertical plane
and above the horizontal plane. At this time the angular velocity of the inter-
mediate mechanism is a maximum, and of course in excess of that of the
driving mechanism.
Since the minimum angular velocity of the intermediate mechanism is equal
to the angular velocity of the driving mechanism, which is constant, and
since the minimum speed of the said intermediate mechanism only occurs at
two instants, and. since also between these two instants the said speed is greater
than the minimum, therefore the average angular velocity of the intermediate
mechanism is greater than that of the driving mechanism.
When, now, more than two transmitting levers are employed in a set, the
period during which one of the transmitting devices is operating the interme-
diate mechanism is reduced, this period depending upon the number of such
transmitting levers in a set. In other words, only that transmitting lever
which is nearest the vertical plane and above the horizontal plane will drive
the intermediate mechanism, and consequently, when one transmitting device
above the horizontal plane has passed the vertical plane, the next following
transmitting lever above the horizontal plane will be approaching said plane,
and when the one which is approaching becomes closer to the said vertical
plane than is the transmitting lever which is receding, the closer one is locked
to the driving mechanism and the other is thereby released or unlocked there-
from. In this manner the average angular velocity of the intermediate
mechanism is kept much closer to the maximum with a number of transmit-
ting levers than if only two were used, and the fluctuations in angular velocity
of said intermediate mechanism becomes less in proportion to the increase in
number of transmitting devices in a set.
Referring now to the method of transmitting motion from the intermediate
mechanism to the driven mechanism and considering only those transmitting
devices which are between the intermediate mechanism and the driven mechan-
ism, it will be found that the rotation of the said intermediate mechanism will
cause the transmitting lever which is below the horizontal plane and nearest
the vertical plane to become locked to the driven mechanism, thus causing the
driven mechanism to be turned by the intermediate mechanism.
The other transmitting lever which is at that time above the horizontal
plane will be carried around idly by the rotation of the intermediate mechan-
ism, owing to the fact that its cam or locking device is being moved with a
peripheral speed less than that of the periphery of the disc of the driven
mechanism. In other words, the angular velocity of the transmitting lever
which is below the horizontal plane and nearest the vertical plane will be
greater than the angular velocity of any other transmitting lever in the same
set, and the angular velocity of the driven mechanism is equal to that of the
said transmitting lever to which it is locked. Hence its angular velocity must
be greater than that of any other transmitting device than the one to which it
is locked and consequently it will tend to keep unlocked the cams of all other
transmitting devices than the one to. which it is locked.
It will be noted, moreover, that the angular velocity of each transmitting

page_text: lever below the horizontal plane is greater than that of the intermediate
mechanism, whereby it results that the number of rotations per unit of time
of the driven mechanism is greater than that of the intermediate mechanism.
Thus, as there is an increase in the number of rotations per unit of time
between the driving mechanism and the intermediate mechanism and also
between the latter and the driven mechanism, the driven mechanism will run
at a greater angular velocity than will the driving mechanism.
It is to be observed that when the axes of the intermediate mechanism and
of the driving and driven mechanisms are concentric, the driven mechanism
is moved at the same angular velocity as the driving mechanism.
Furthermore, when the axis of the intermediate mechanism is not concentric
with the axes of the driving and driven mechanisms, there is an increase in
speed of the driven mechanism over that of the driving mechanism, and it
will be obvious that this increase of speed varies with the amount of eccentri-
city of the axis of the intermediate mechanism. Hence, by shifting the
journal-bearing Fig. 2 of the intermediate mechanism, in the construction
shown in Figs. 1 and 2, the speed of the driven mechanism with relation to
that of the driving mechanism may be varied.
In order to provide a simple automatic means for producing the desired
adjustment of the axis of rotation of the intermediate mechanism with rela-
tion to the axis of the driving or driven mechanism, a suitable motion-resolv-
ing mechanism is employed as a transmitting mechanism, so that a part of the
rotary motion of the driving mechanism is converted into a rectilineal result-
ant tending to shift the axis of the intermediate mechanism in one direction.
Two sets of such motion-resolving transmitting devices are employed, one
set between the driving mechanism and the intermediate mechanism and the
other between the intermediate mechanism and the driven mechanism, these
sets being arranged to produce rectilineal resultants which tend to act in oppo-
site directions.
It is clear that with the driving mechanism running at a constant speed
and force, any change in the load of or resistance to be overcome by the driven
mechanism must be compensated for by a variation in the speed of said driven
mechanism. For example, if the load on the driven mechanism is increased,
the speed of said driven mechanism must be correspondingly reduced, as other-
wise a change of the power of the driving mechanism would be necessary.
Furthermore, when the speed of the driven mechanism is to be reduced, the
axis of rotation of the intermediate mechanism must be shifted toward the
axes of the driving and driven mechanisms. Hence it follows that with an
increase of the load on the driven mechanism, the eccentricity of the interme-
diate mechanism should be reduced while when the load on the driven
mechanism is reduced the eccentricity of the intermediate mechanism should
be increased.
The motion-resolving transmitting devices employed for the production of
oppositely-acting rectilineal resultants are therefore so arranged that an increase
in the load on or of the resistance of the driven mechanism will cause an
increase in that rectilineal resultant which tends to cause a shifting of the axis
of the intermediate mechanism in the direction of reducing the eccentricity
of said axis, and that a reduction in said load or resistance will cause a reduc-
tion in said rectilineal resultant.
As a consequence, in the first instance, the increase in the rectilineal result-
ant tending to requce the eccentricity of the axis of the intermediate mechanism
will enable it to overcome the other oppositely-acting rectilineal resultant and
thereby shift the intermediate mechanism so that its axis will be less eccentric
than before.
In the second instance, riz.: when the rectilineal resultant tending to reduce
the eccentricity of the axis of the intermediate mechanism is reduced, then
the oppositely-acting resultant is enabled to overcome the one which has been

page_text: reduced and to shift the intermediate mechanism so that its axis becomes more
eccentric.
It will be apparent, moreover, that the increase or decrease in the resultant
which tends to reduce the eccentricity of the axis of the intermediate mechan-
ism must not be permanent, even though the increased load on the driven
mechanism remains permanent, since if it were, every increase in load whether
great or small on the driven mechanism would move the axis of the interme-
diate mechanism to its position of concentricity, or if actual concentricity be
prevented, to its position of least eccentricity, thereby always producing the
same speed-ratio between the driving and driven mechanisms, which would not
be proper.
Hence, it is requisite that the motion resolving transmitting devices be so
arranged that upon a shifting of the axis of the intermediate mechanism a
change in the ability of the transmitting devices to produce rectilineal resultants
will take place, the movement of the axis of the intermediate mechanism to a
position of less eccentricity causing that set of transmitting devices whose
rectilineal resultant has produced such movement, to assume a condition in
which it cannot produce so great a rectilineal resultant as it did before the said
movement, whereas the other set of transmitting devices assume a condition
wherein they can produce a greater rectilineal resultant than they did before.
By this arrangement, the two oppositely-acting rectilineal resultants are
brought into equilibrium with each other, so that by a variation in the load
the driven mechanism, the axis of the intermediate mechanism will be
shifted to a position where the speed ratio between the driving and driven
mechanisms will be proportioned to the total load on the driven mechanism.
on
In order to obtain all these results, it has been found that a transmitting
mechanism consisting of two sets of oppositely-arranged toggle-transmitting
devices are of a special advantage. The specific arrangement and construc-
tion of one form of the invention embodying such toggle-transmitting devices
will now be described.
Referring to Fig. 4, R³ is a ring which forms part of the intermediate
mechanism, similar to the ring R in the apparatus shown in Figs. 1 and 2.
At o is shown the driving shaft on which are fixed the discs ³, the two forming
a driving mechanism similar to that in Figs. 1 and 2.
Each transmitting device consists of toggle-arms m³, pivotted to the ring R³
at 1, and loosely mounted on the driving-shaft 2, these arms being provided
with locking devices in the form of cams c5.
The apparatus just described has all of the functions of that shown in Figs. 1
and 2 and the following in addition:
When a transmitting device is above the horizontal plane and nearest the
vertical plane, it is locked to the driving mechanism by its cam mechanism,
and owing to its action as a toggle-arm will tend to force the ring R³ to a
position where its axis will be more eccentric. The other toggle-arms not
being locked to the driving mechanism will not resist this tendency to move
the ring, and in case the said movement takes place will be bent back further
upon their central pivots.
As will be obvious to those skilled in the art, the toggle-device which is
locked to the driving mechanism, if it be prevented from moving the ring R³
in a rectilineal direction, will exert a pressure in such direction and at the
same time by the rotation of the driving mechanism will cause a rotation of
the ring R
As the direction on which the operating toggle-devices tend to move the
ring R is a radial one, such direction is constantly changing with the rotation
of the said transmitting device. But, owing to the fact that the axis of the
intermediate mechanism is mounted for movement only in a fixed rectilineal
direction, the radial movement which the operating transmitting device tends

page_text: to cause is converted into a tendency to move the axis of the intermediate
mechanism in said fixed rectilineal direction.
The rectilineal resultant produced by the operating toggle-transmitting
device depends upon the condition of the same, that is to say, upon the size of
the acute angle included between the longitudinal axes of the two parts of the
Loggle-device and is inversely proportional to such angle, the resultant becom-
ing greater as the angle decreases and smaller as the angle increases. As a
consequence, the movement of the axes of the intermediate mechanism toward
a position of greater eccentricity will cause the toggle-transmitting devices 'to
continuously assume conditions where the rectilineal resultant which it can
produce with a constant power on the driving mechanism grows constantly less.
On the other hand, the ability of the said toggle-transmitting device to pro-
duce a rectilineal resultant grows constantly greater as the eccentricity of the
intermediate mechanism becomes smaller.
Referring now to the set of toggle-transmitting devices between the inter-
mediate mechanism and the driven mechanism, it is to be observed that the
points of connection of the said toggle-transmitting devices with the inter-
mediate mechanism are respectively diametrically opposite to the points of con-
nection of the corresponding toggle-transmitting devices between the driving
mechanism and the intermediate mechanism, as will be seen in Fig. 4. More-
over, the acute angles formed between the longitudinal axes of the two parts
of these transmitting devices are of opposite sign to those of the first set of
transmitting devices, or in other words, the central pivots of the first set of
transmitting devices all lie to one side of the radii through their points of connec-
tion with the intermediate mechanism while the central pivots of the second
set of transmitting devices all lie on the opposite sides of their corresponding
radii.
It is to be noted that in the construction, as in that illustrated in Figs. 1
and 2, the driven mechanism is rotated by means of that transmitting device
which, for the time is below the horizontal plane and nearest the vertical plane,
the other transmitting devices of the same set being merely pulled around
idly on their axes of rotation by the intermediate mechanism and coming into
action only after they have respectively passed below the horizontal plane and
one after the other come into a position which brings them nearest the vertical
plane.
When a transmitting device m² of the second set is locked by its cam c6 or
other locking device to the driven mechanism, it produces a rectilineal result-
ant which is opposite in direction to that produced by the operating transmitting
device of the first set. Therefore, as the resultant produced by the operating
transmitting device of the first set (and which I will call the first resultant)
tends to move the axis of the intermediate mechanism into a position of greater
eccentricity and the resultant of the operating transmitting device of the second
set (which I will call the second resultant) tends to move the said axis of the
intermediate mechanism into position of less eccentricity, so it results either
that no movement of the said axis occurs, or that it occurs in the direction of
that resultant which is greater. But as the shifting of the axis of the inter-
mediate mechanism causes a change in the ability of the operating toggle-
transmitting devices of the first and second set respectively to produce their
respective rectilineal resultants, owing to a change in the angles made by the
two parts of the toggle-devices, and since, as will be observed from the draw-
ings, an increase in the first resultant is accomplished by a decrease in the
second resultant and vice versa, the automatic shifting of the axis of the inter-
mediate mechanism due to a preponderance of one rectilineal resultant over
the other will bring about an equilibrium of the said resultants, and thereby
stop the shifting of the said axis of the intermediate mechanism, until such
time as the said equilibrium of the rectilineal resultants is again destroyed.

page_text: This destruction of the equilibrium of the two rectilineal resultants is
brought about by a change in the load upon the driven mechanism. For
example if the load is suddenly increased, its initial tendency would be to slow
down the driving mechanism, thus tending to drag on the operating toggle-
transmitting device of the second set, and, owing to the momentum of the inter-
mediate mechanism, the said operating toggle-transmitting device endeavours
to suddenly increase its acute angle, that is to say, it tends to straighten out.
At the same time, said transmitting device tends to hold back the intermediate
mechanism and thus produces a tendency in the operating toggle-transmitting
device of the first set to straighten out or increase its acute angle.
If now the axis of the intermediate mechanism is concentric with the axes
of the driving and driven mechanisms, the opposite rectilineal resultants pro-
duced by the increase in load of the driven mechanism would be equal, and
hence, no movement of the axis of the intermediate mechanism would occur.
But, if the axis of the intermediate mechanism is eccentric, the operating
transmitting device of the second set will be in a somewhat more folded up
position than will that of the first set, and hence the second rectilineal resultant
will be greater than the first rectilineal resultant and the axis of the interme-
diate mechanism will be shifted into a position of less eccentricity, until equi-
librium of the two resultants is brought about, as herein before explained.
In order to prevent the parts from ever assuming a position when the two
operating transmitting devices of the first and second sets respectively will have
the same acute angles, it is necessary to prevent the axis of the intermediate
mechanism from at any time assuming a condition of concentricity with the
axes of the driving and driven mechanisms. This may be done in any suitable
way as by limiting the movement of the sliding arms, for example, by the
pin z, in the direction of concentricity.
In Figs. 6 and 7 a modified construction of the power-transmitting device
is shown. In this construction the transmitting devices, instead of being acted
upon by the driving shaft, as in Figs. 4 and 5, are actuated by the ring R³
which is mounted on the driving shaft and transmits motion to the intermediate
mechanism, in the same manner as the intermediate mechanism in Figs. 4
and 5 transmits motion from the intermediate mechanism to the driven axle.
The transmission of motion from the intermediate mechanism, as shown in
Figs. 6 and 7, is accomplished in a manner similar to the transmission of
motion from the driving shaft to the intermediate mechanism, as shown in
Figs. 4 and 5. The driving shaft and the transmitting devices act on the inter-
mediate mechanism and the latter acts by its transmitting devices on the driven
shaft in exactly the same manner as the driving shaft in Figp. 4 and 5 acts by
its transmitting devices on the intermediate mechanism and the latter by the
second set of transmitting devices on the driven shaft. The letters of reference
are applied in Figs. 6 and 7 to the same parts as in Figs. 4 and 5, so that the
description of the operation of the latter will apply equally to explain the
operation of the two sets of transmitting devices shown in Figs. 6 and 7.
Figs. 8 and 9 show the application of the invention to the driving gear of a
bicycle, H being a casing and H₁ a pedal-lever having a crank-shaft H³, pre-
ferably formed integral therewith and passing through the casing, the other
end of the said shaft being provided with another pedal-lever H³, secured to
said crank-shaft by a lock-nut H. Fastened to the shaft and pedals aforesaid
is a sleeve I, adapted to turn with the shaft and pedal-levers and mounted
upon anti-friction rollers J, which rollers are supported upon and turn in bear-
ings h of the casing H. To the sleeve I is secured by means of screw-connec-
tions a collar Q, having inclined recesses q¹, in which are located locking balls
or rollers q. Around the collar are located three rings m, each carrying a
pin n which is connected to a link n¹. These links n' are mounted at their other
ends upon pins n² of a rotable and bodily movable ring U.
In order to render the ring U rotatable, it is arranged to roll on anti-friction

page_text: bearings of a ring U2, which is pivotted to and swings about a shaft or
stud U, the arrangement of all the parts being such that the axis of rotation
of the ring U can never become concentric with the axis of rotation of the
shaft H, this being prevented by one edge of the ring U2 coming in contact
with the casing.
By this mechanism the ring U, as will be seen, is capable of movement from
a position where it is only slightly eccentric to a position of greater eccen-
tricity.
Upon the opposite side of the ring U are corresponding rings m, having
pins n, similar to those previously described as pivotally connected to pins
of the ring U. A collar Q is loosely mounted on the sleeve I, and fixed to the
front sprocket Q2 by a screw-connection as shown. Anti-friction rollers are
provided to permit the rotation of the said collar and its annexed parts in the
frame H.
The operation of this device is as follows:-
-
When power is applied to the pedal-lever, the crank-shaft is revolved and
with it the sleeve I, the latter rolling upon the bearings J and causing the rota-
tion of the collar Q. As the latter rotates the rings m will intermittently
and seriatim become locked to the said collar Q by the locking balls or rollers q,
thereby rotating the ring U through the medium of the respective links
The said ring U will in turn rotate the opposite links n¹, which will then rotate
the second set of rings m, which by the corresponding locking rollers (Fig. 9)
will successively bind upon the collar Q¹, and thereby turn the sprocket-
wheel Q which drives the bicycle in the usual manner.
Upon an increased resistance being offered to the progress of the bicycle,
assuming the propelling power to remain unchanged, the ring U2 will be shifted
to bring the axis of the ring U into a position of less eccentricity with refer-
ence to the axis of the driving or crank-shaft H2.
Thereupon the speed ratio of the driving and driven mechanism is so changed
that the driven mechanism, viz. the collar Q¹ and its sprocket Q will be turned
at a reduced speed compared with the speed which said driven mechanism had
before the increased resistance to the progress of the wheel. Thus, by this
mechanism when a hill or rough road is reached, the cyclist will be enabled
to pass the same without the expenditure of extra exertion, although of course,
at a slower speed.
When, however, the resistance to the progress of the wheel is reduced, the
ring U and with it the ring U shifts to a position of greater eccentricity, thus
giving a greater speed ratio between the driven and the driving mechanisms,
whereby the same amount of exertion of the rider as before, will cause the
vehicle to progress at a greater speed than when it was encountering more
resistance to its progress.
It will be seen that in this construction the shaft H2, sleeve I and collar Q
may be considered as the driving mechanism, the collar Q and sprocket-
wheel Qas
the driven mechanism, while the ring U is the intermediate
mechanism, having a movable or adjustable axis of rotation, and the links n' n¹
and their two sets of rings m m form the toggle-transmitting devices.
Furthermore, the inclined recesses shown at q¹, Fig. 9, together with the
balls or rollers q located therein form the locking mechanism or cam-locking
devices.
In Fig. 10 the improved power-transmitter is shown as applied for use on
the counter-shaft of a suitable power-driven machine.
R6 represents a pulley, loosely mounted on the counter-shaft 0. This pulley
is rotated by any suitable motive power. The general arrangement of this
device is the same as that shown in Fig. 7; the pulley R taking the place of
ring R. The driving device which transmits the motion from the pulley to
the intermediate mechanism, is somewhat different from that represented in
Fig. 7, as it does not consist of toggle-levers but of straight arms similar to

page_text: those shown in Fig. 1; but instead of having pins on the pulley engaging
with longitudinal slots on the arms, the latter are made of two telescoping
parts 16, by which the actual length of the arms can be changed. The inner
members of these arms are in the form of clutch-rings similar to the inner
members of the toggle-levers in Fig. 9, and are placed on a sleeve o through
which the shaft o is passed from the driving pulley Re to the driven pulley R7.
This sleeve has its bearings in a ring which supported by a hanger-rod F7.
To the upper end of the hanger-rod F7 is keyed a sleeves having three longi-
tudinal grooves and intermediate threaded portions. The sleeve s engages
with the interior portion of a stationary hanger G7 which is likewise provided
with three interior grooves and intermediate threaded portions, so that the
sleeve s can either be liberated from or placed in mesh with the threaded por-
tions of the hanger G. A helical spring s is interposed between an interior
shoulder of the hanger and the upper end of the sleeve and tends to force
the rod 17 down when liberated by giving it a one-third turn on its axis so
that the sleeve o³ can assume a position of greatest eccentricity to the shaft o.
On the opposite side of the ring are arranged on the sleeve o three clutch-
rings m which form with the levers m toggle-levers in the same manner as
the toggle-levers in Fig. 9. The outer ends of the members m engage pins I'
on pulley R which latter is also loosely mounted on shaft o. Rotary motion
is transmitted from the pulley R7 by a belt to a pulley on the machine to be
driven. The arrangement of the straight arms 167 on the driving (left) side
of the transmitter excludes the automatic action of this side as it was shown
before that toggle-levers are necessary for automatic power-transmitting action.
The driven (right) side of the transmitter has a set of toggle-levers as trans-
mitting devices and therefore automatic power-transmitting action. The con-
structions shown in previous figures show that the tendency of each toggle-lever
when in action is to stretch out, that is to say to open its angle. When such
a toggle-lever is arranged in reversed position with its angle opening, it will
have a closing tendency. The toggle-levers in Fig. 10 are so arranged that
they have a constant tendency to close or to bring the sleeve o in a concentric
position. The action of the spring sand of the load upon pulley Rare
therefore opposed to each other, a greater eccentricity of the sleeve and a greater
speed of the pulley R resulting when a smaller load is on the pulley R,
while a lesser degree of eccentricity of the sleeve and a smaller speed of
the pulley will result with the increase of the load on the pulley. The
action of the spring s is only to be overcome by the load as the straight levers
on the driving side are unable of having any concentric or eccentric tendency
by virtue of their ability of longitudinally sliding, or in other words there is
no re-action of the spring-pressure upon the driving force.
When a certain constant speed is desired and the automatic action of the
transmitting device is to be interrupted the hanger-rod F is first vertically
shifted against the tension of the spring s to the desired position and then
turned for a third of its rotation so that its threaded portions interlock with
the threaded interior portions of the hanger G, the higher or lower position
of the hanger-rod F7 producing a smaller or greater eccentricity of the sleeve o³
and consequently a smaller or greater speed of the pulley R and the machine
driven thereby. By giving the hanger-rod another turn, it is disengaged
from its hanger and thereby the automatic action of the intermediate power
transmitting devices restored in proportion to the resistance of the load."
It is obvious that the power-transmitting mechanism herein described can
be modified so as to be applicable in all cases in which a constant power has
to overcome varying load-resistances, and to adapt itself automatically to the
same. It is not only applicable for bicycles or other velocipedes and counter-
shafts, but may be adapted to automobiles, hoisting machinery, the spindles
of machine tools and like machine-elements or any other uses to which same
may be applicable.

page_text: Having now particularly described and ascertained the nature of this said
invention, and in what manner the same is to be performed, I declare that what
I claim is
1. The combination with a driving mechanism and a driven mechanism, of
means for transmitting power from the driving mechanism to the driven
mechanism, and means for permitting the adjustment of said transmitting
means whereby the speed ratio between the driving and driven mechanism may
be altered.
2. The combination, with a revoluble driving mechanism and a revoluble
intermediate mechanism, of a plurality of transmitting devices connected to
said revoluble intermediate mechanism, detachable connecting devices between
the transmitting devices and the driving mechanism, and a driven mechanism
operated by the intermediate mechanism...
3. The combination, with a revoluble driving mechanism, and a revoluble
intermediate mechanism having their axes of revolution non-concentric, of a
plurality of transmitting devices connected to the said revoluble intermediate
mechanism, detachable connecting devices between the transmitting devices
and the driving mechanism and a driven mechanism operated by the inter-
mediate mechanism.
4. The combination, with a revoluble driving mechanism and a revoluble
intermediate mechanism, of a plurality of transmitting devices connected to
the said revoluble intermediate mechanism, detachable connections between the
transmitting devices and the driving mechanism, means for permitting the
alteration of the relative positions of the axes of rotation of the power-supply-
ing mechanism and of the intermediate mechanism, and a driven mechanism
operated by the intermediate mechanism.
5. The combination, with a revoluble driving mechanism, and a revoluble
intermediate mechanism, of a plurality of transmitting devices connected to
the said revoluble intermediate mechanism, automatic detachable connections
between the transmitting devices and the driving mechanism, means for chang-
ing the relative positions of the axes of rotation of the driving mechanism
and the intermediate mechanism, and a driven mechanism operated by the
intermediate mechanism.
G. The combination, with a revoluble driving mechanism and a revoluble
intermediate mechanism, said mechanisms having their axes capable of eccentric
Iocation relative to each other, of a plurality of transmitting devices acting on
the revoluble intermediate mechanism, intermittently-acting means for con-
necting each transmitting device to the driving mechanism during a portion of
the rotation of the latter and then disconnecting it therefrom, and a driven
mechanism operated by the intermediate mechanism.
7. The combination, with a revoluble driving mechanism and a revoluble
intermediate mechanism, of a plurality of transmitting devices acting on the
revoluble intermediate mechanism, intermittently-acting means for connecting
each transmitting device to the driving mechanism during a portion of the
rotation of the latter and then disconnecting it therefrom, means for permit-
ting the alteration of the relative positions of the axes of the power-supplying
mechanism and the intermediate mechanism, and a driven mechanism operated
by the intermediate mechanism.
8. The combination, with a revoluble driving mechanism and a revoluble
intermediate mechanism whose axis is capable of an eccentric location relative
to that of the driving mechanism, of a plurality of transmitting devices acting
on the revoluble intermediate device, cam-devices for connecting each trans-
mitting device to the driving mechanism during a portion of the rotation of
the latter and then allowing it to be disconnected therefrom, and a driven
mechanism operated by the intermediate mechanism.
9. The combination, with a revoluble driving mechanism and a revoluble
intermediate mechanism whose axis is capable of an eccentric location relative

page_text: to that of the driving mechanism, of a plurality of transmitting devices acting
on the revoluble intermediate mechanism, frictionally-controlled mechanism
for detachably connecting each transmitting device to the driving mechanism
during a portion of the rotation of the latter, and a driven mechanism operated
by the intermediate mechanism.
10. The combination, with a revoluble driving mechanism, a revoluble
driven mechanism, and a revoluble intermediate mechanism, of two sets of
transmitting devices, the first set between the driving mechanism and the inter-
mediate mechanism, the second set between the intermediate mechanism and
the driven mechanism, and means for permitting the adjustment of the axis
of the intermediate mechanism relative to that of the driving and driven
mechanism.
11. The combination, with a revoluble driving mechanism, a revoluble
driven mechanism, and a revoluble intermediate mechanism, of two sets of
transmitting devices both connected to the intermediate mechanism, locking
devices arranged to lock the first set of transmitting devices to the driving
mechanism, and locking devices arranged to lock the second set of transmitting
devices to the driven mechanism.
12. The combination, with a revoluble driving mechanism, a revoluble
driven mechanism, and a revoluble intermediate mechanism, of two sets of
transmitting devices, both connected to the intermediate mechanism, frictional
locking devices between the two sets of transmitting devices and the driving
and driven mechanisms respectively, and means for permitting the adjustment
of the axis of rotation of the intermediate mechanism.
13. The combination, with a driving mechanism and a driven mechanism, of
transmitting means intermediate of the driving and driven mechanism and
adjustable by the resistance of the driven mechanism, whereby the speed trans-
mitted from the driving mechanism to the driven mechanism is varied by the
load on the latter.
14. The combination, with a revoluble driving mechanism, and a revoluble
driven mechanism, of a revoluble intermediate mechanism, transmitting
devices connecting the driving mechanism and the intermediate mechanisms
and tending to shift in one direction the axis of the said intermediate
mechanism, and transmitting devices connecting the intermediate mechanism
and driven mechanism and tending to shift in an opposite direction the said
axis of the intermediate mechanism.
15. The combination, with a revoluble driving mechanism, a revoluble driven
mechanism and a revoluble intermediate mechanism, of two sets of toggle-
transmitting devices, one set connecting the driving mechanism and the inter-
mediate mechanism and the other set connecting the intermediate mechanism
and the driven mechanism.
16. The combination, with a revoluble driving mechanism, a revoluble driven
mechanism, and a revoluble intermediate mechanism, of two sets of oppositely-
acting toggle-transmitting devices, one set connecting the driving mechanism
to the intermediate mechanism and the other set connecting the intermediate
mechanism to the driven mechanism.
17. The combination, with a revoluble driving mechanism, a revoluble driven
mechanism, and a revoluble intermediate mechanism, the axis of the interme-
diate mechanism being relatively movable towards the axes of the driving and
driven mechanisms, of two sets of toggle-transmitting devices, one set con-
necting the driving mechanism to the intermediate mechanism, the other set
connecting the intermediate mechanism to the driven mechanism.
18. The combination, with a revoluble driving mechanism, and a revoluble
driven mechanism having their axes in line with each other, of a revoluble
intermediate mechanism having its axis of rotation movable with relation to
the axis of the driving and driven mechanism, and two sets of toggle-trans-
mitting devices, one set acting in a direction opposite to the other, one set

page_text: connecting the driving mechanism to the intermediate mechanism, the other
set connecting the intermediate mechanism to the driven mechanism.
19. The combination, with a revoluble driving mechanism, a revoluble driven
mechanism, and a revoluble intermediate mechanism having its axis adjustable
with relation to the axes of the driving and driven mechanism, of two sets of
toggle-transmitting devices, connected to the intermediate mechanism, means
for intermittently locking the driving mechanism to and unlocking it from the
first set of toggle-transmitting devices, and means for intermittently locking
the driven mechanism to and unlocking it from the second set of toggle-trans-
mitting devices.
20. The combination, with a revoluble driving mechanism, a revoluble driven
mechanism, and a revoluble intermediate mechanism, of two sets of transmit-
ting devices connected to the intermediate mechanism, each set comprising a
plurality of toggle devices, means for locking the toggle devices of one set
seriatim to the driving mechanism and unlocking them therefrom, and means
for locking the toggle-devices of the other set seriatim to the driven mechanism,
and unlocking them therefrom.
21. The combination, with a revoluble driving mechanism, a revoluble driven
mechanism, and a revoluble intermediate mechanism having its axis of rota-
tion adjustable with relation to the axes of the driving and driven mechanism,
of two sets of oppositely-acting toggle-transmitting devices connected to the
intermediate mechanism, frictionally-actuated locking devices between the
driving mechanism and one set of transmitting devices, and frictionally-actuated
locking devices between the driven mechanism and the other set of transmitting
devices.
D
11
TONGUE & BIRKBECK,
31, Southampton Buildings, Chancery Lane, London, W.C.,
Agents for the Applicant.