Improvements in and relating to Variable Speed Gear for Cycles.
Year: 1896

page_text: Date of Application, 17th June, 1896-Accepted, 15th Aug., 1896
COMPLETE SPECIFICATION.
Improvements in and relating to Variable Speed Gear for Cycles.
1, RAYMOND SENDRANIE of 36 Rue St. Ferdinand, Paris, in the Republic of
France, Engineer, do hereby declare the nature of this invention and in what
manner the same is to be performed to be particularly described and ascertained in
and by the following statement :-
My invention relates to an improved variable speed gear for cycles allowing of
varying the velocity for the surmounting of hills or like purposes by the simple
manipulation of a lever which operates a clutch applied to gearing which can be
held either on cycles with chains or those without chains.
This gear is shown in the annexed drawing in which
Fig. 1 is the longitudinal section through the hub of the driving wheel of a cycle
with chain to which this mechanism for changing the velocity has been applied.
Fig. 2 is an elevational section on the line a-b of Fig. 1.
Figs. 3 to 10 are details of the essential parts of the gear.
Fig. 11 is a plan of a connecting gear applied to a cycle provided with this
mechanism for change of velocity.
Fig. 12 is a plan view of the arrangement of this mechanism when the transmission
is made by bevelled gearings.
Fig. 13 is a view of a cycle provided with my mechanism for change of velocity
with chain gear.
The wheel c (Figs. 1 and 2), the axle x of which is fixed to the flat and bent
piece of metal s which extends from the end of the tube t connecting the treadle
with the nave y of the driving wheel, receives its movement from the chain
(Fig. 13) and by means of its two inner series of teeth ranges, gears with the
two pinions d and e fitted upon the extremity of the nave y and connected
alternatively to it by the sleeve g according as the latter is moved in the one or
the other direction.
This sleeve g has the form shown in Figs. 7 and 8.
In order to allow of the introduction and the operation of the sleeve the nave y
is slotted at its extremity to a certain length in two diametrically opposite places
(Figs. 1 and 3).
In order that the loose pinion does not turn upon the nave itself a ring h of
hardened steel or in any other appropriate metal is interposed between the nave y
and the pinions d and e. This ring is also slotted (Figs. 1, 2 and 4) in order to
allow its introduction and the operation of the sleeve. A small pin i prevents the
rotation of socket upon the nave.
The ball cup is provided with screw threads and its projecting shoulder prevents
dislodgment of the socket and of the pinions.
The sleeve g is shown connecting the small pinion d to the nave y: for displacing
the sleeve it is sufficient by means of the rod k and angle lever 1: to move the
rod m in the interior of the nave for a certain distance limited by the contact of
the head of the lever against the socket n.
The collars o and o¹ (Figs. 1, 9, and 10) fixed upon the rod m are thus displaced:
the one spring r is released and the other spring is compressed, the loose collar p.
is therefore pushed by the spring and moves the sleeve g which is disengaged
from the indents of the pinion d (Figs. 1 and 6), and when on further rotation the

page_text: projections of the sleeve meet two of the indents of the larger pinion e (Figs. 1, 2,
and 5) they enter such indents and engage the pinion e to the nave.
These projections are provisionally lodged in a circular hollowing provided in
the two naves of the pinion, and of width a little superior to that of the projections
in order to allow of the latter completely leaving the indents of one of the pinions
before gearing with those of the other.
In order to cause the sleeve g to return to the position indicated by Fig. 1, it is
sufficient to exercise a pressure upon the lever I by means of the rod k, the
spring is relaxed and the compression of the spring causes the projections of
the sleeve to leave the indents of the larger pinion in order to enter those of the
smaller pinion.
In order to reduce the friction of this system to a minimum the contact of the
sleeve g and of the collar p is made by the interposition of a ring of balls; but it
will be well understood that this interposition is not indispensable.
The regulation of the tension of the chain is made by means of the slide u
connected with the axle a, the rotation of a screw nut in one direction or in the
other moves more or less the slide u froin or to the pedal crank shaft.
In order to use a connecting rod gear with this mechanism (Fig. 11) one of the
cranks a of the treadles is bent twice at right angles and upon this angle is
articulated the connecting rod 6 connected on the other part to a stud c³ fixed
excentrically to the driving wheel ³ (Fig. 11).
For transmission by bevelled gear I arrange upon the pedal crank shaft d' a
bevelled toothed wheel e which gears with a pinion e fitted upon the shaft f*.
This shaft bears at its posterior extremity a double-bevelled toothed wheel k
the two series of teeth k and k gear respectively with bevelled pinions m and m³
fitted upon the nave y and of which either can be connected rigidly with the nave
by means of the arrangement of movable sleeve and parts relating thereto shown
in Figs. 1 and 2 allowing of changing the rate of the driving gear in order to modify
the velocity.
The working is easily understood.
The shaft d moved by the pedals transfers by means of the wheel cits movement
of rotation to the pinion e and to the shaft which by the tooth series and k
of the wheel k operates the pinions m' and m' at different speeds one of which
moves the driving wheel.
The shaft f can be enclosed in the interior of one of the tubes of the framing.
The lever (Fig. 1), 3 (Fig. 11), and (Fig. 12) of each of the arrangements is
articulated to a rod k (Figs. 1 and 14) also articulated to a bell crank lever h
connected to a second rod h which the cyclist can operate in order to change the
velocity, by means of a handle lever k³ articulated upon the side of the tube of the
upper part of the framing of the cycle.
Having now particularly described and ascertained the nature of this said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
In a variable speed gear for cycling;
1. The combination of the following parts; a bell crank operated by the
rod k, a rod m upon which are fixed the two collars o and o¹ compressing alternately
the springs r and according to the direction of the movement given to the rod m,
the compressed spring ror driving in one direction or the other, a loose collar p
which operates the sleeve g which renders loose or fixed one of the two straight
pinions d and e or the two bevelled pinions m and m upon the nave y or y
substantially as illustrated and described.
2. The combination of the mechanism described in Claim 1 for rendering loose
or fixed one of the two straight pinions d and e with a wheel c with two interior
rows of teeth gearing with the two pinions d and e and receiving its movement from
a chain or from a connecting rod.

page_text: 3. The combination of the mechanism described in Claim 1 for rendering loose
or fixed one of the two bevelled pinions m and m³, with a bevelled wheel with
two rows of teeth and k gearing with the two pinions m and m and receiving
its movement from a shaft operated by the bevelled wheels e and e*.
Dated this 17th day of June 1896.
HERBERT HADDAN & Co.,
18, Buckingham Street, Strand, London, W.C., Agents for Applicant.