Improvements in velocipedes.
Year: 1895

page_text: Date of Application, 13th July, 1895-Accepted, 24th Aug., 1895
Improvements in velocipedes.
We RAPHAEL SCHWEERS, Government Architect, of Wilsnackerstrasse 60,
HENRY MAYER, Merchant of Königgrätzerstrasse 81, and LUDWIG EHRLICH,
Merchant of Mittelstrasse 9 and 10, all in Berlin in the Empire of Germany 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:-
The object of the present invention is to provide means by which the gearing
between the pedal crank shaft and the hind wheel may be altered at any time
during the running of the wheel without necessitating a decrease of the speed.
For this purpose there are keyed on to the pedal crank shaft two chain wheels of
different diameter, each of which is geared with a corresponding chain wheel fitted
loosely on the nave of the hind wheel, that is to say, separate chains pass over said
wheels and those on the hind wheel, either of which latter is adapted to be securely
fastened on to the nave of the driving wheel by a coupling operated by a rod and
devices hereinafter described so that either the one or the other of the two gearings
may be employed.
In the annexed drawing,
Fig. 1 is a section through the driving wheel nave, parallel to the axle. Fig. 2
is a vertical section thereof.
Fig. 3 is a section through the pedal crank shaft.
Figs. 4 to 8 represent details.
Fig. 9 a full view of the improved bicycle.
On each end of the nave a of the driving wheel is loosely attached a toothed
wheel c, c respectively, each having a flange b with circular coupling openings b¹,
said wheels being prevented from sliding off their bed by circular discs d secured
to the nave by means of the spokes of the wheel. From said toothed wheels c
and c pass chains to two toothed wheels C and C¹ (see Fig. 3) secured to the pedal
crank shaft. When it is desired to actuate the driving wheel by means of one of
said chains, it is necessary to couple the respective toothed wheel on the hind
wheel on to the nave a. To effect this a coupling bolt e is adapted to be slid to
one of the end positions to the coupling slot of the wheel to be coupled. As soon
as the bolte has passed into one of the coupling slots, the respective wheel is
securely connected with the nave, while this gearing is employed the other is
disengaged. By turning the coupling bolt it is bound to be longitudinally displaced,
as the latter as well as one of the beds f and f¹ of the coupling bolt which are
rivetted on to the nave, is provided with an archimedial screw. The turning of
the coupling bolt is effected by the cylinder g which by means of groove and
tongue acts upon said bolt. If the cylinder is provided with screw thread and
one of the beds with groove and tongue the coupling bolt will also be given a
longitudinal displacement when turning. The same displacement will occur when
the groove and tongue is replaced by another screw thread opposite to the first one.
To the crank arm of the cylinder g is attached a bar i which is fastened to the
rim or spokes in such manner that it may freely move in a radial direction, that is
to say to and from the axle. At the outer extremity said bar carries a pin k
perpendicular to the plane of the wheel, said pin being adapted to freely rotate
with the wheel as long as one of the slide dogs l, m or 1, n which converge to a
common fulcrum, does not interfere. Should this happen the pin k strikes one of

page_text: the sliding surfaces thereby sliding along to the point l. The radial displacement
which is thus imparted to the pin k is transferred to the coupling bolt e by means
of the rod i and the nut g. At the moment when pin k arrives at point 7, the said
bolte has been moved to the coupling slot 61 whereupon the coupling is accom-
plished by the spring o which, attached to the nave, constantly presses against a
projection of the nut 9 thereby preventing the coupling from becoming loosened.
The fulcrum pin of the slide dogs is located within a casing p containing a small
spiral spring p¹ (see Fig. 6) which urges the slide dogs into one end position by
displacing the bolt on an oblique surface. Said mechanism is brought into the
other end position by pulling the cord 9 (Fig. 9) which is attached to the slide
dogs and adapted to be manipulated from near the handle bars while the velocipede
is running.
Fig. 4 represents the coupling bolt, Fig. 5 shows the cylinder a surrounding it;
Figs. 7 and 8 illustrate the toothed wheel c'.
:
Having now particularly described and ascertained the nature of this invention
and in what manner, the same is to be performed, we declare that what we
claim is.
In a velocipede admitting of a variable speed transmission by means of two loose
chain wheels attachable to the driving wheel and geared by means of chains, with
corresponding chain wheels fixed on to the pedal crank shaft.
$
1. A bolt e provided with threads and fitted in respective cylinders f, f¹ that
are placed horizontally between the loose chain wheels c, c¹ which bolt may, on
being turned by the action of a loose cylinder g, be moved to the right or left and
caused to engage with the coupling openings of one of said chain wheels c, c'.
2. The means for turning the cylinder g receiving the bolt e, consisting of the
levers and rod h, i, k, said rod having at its extremity a pink adapted during the
turning of the wheel to strike against one of two converging slide dogs l, m, and l, n
attached to the frame and keyed to one and the same movable axis.
3. The means for turning the dogs l, m and 1, n by means of a cord connected
with said dogs and running to the handle bars.
4. On the bolt carrying the dogs l, m and l, n, the arrangement of a spring
(Fig. 6) which usually keeps the bolt and the dogs respectively in a certain
position and on releasing the cord q brings them back in that position.
5. On the nave of the driving wheel a spring o adapted to push the bolt e into
the coupling slots 61 thereby insuring the position of the coupling.
Dated this 13th day of July 1895.
HERBERT HADDAN & Co.,
18 Buckingham Street, Strand, London, W.C.,
Agents to the Applicants.