Improvements in Chainless Cycle Driving Gear.
Year: 1898

page_text: Date of Application, 22nd Nov,, 1898—Accepted, 26th Aug., 1899
CUM DEIN DI MUIFICATION
Improvements in Chainless Cycle Driving Gear.
I, LAMBERT SCHORN, of Münsterstrasse 34, Bonn, in the Empire of Germany,
Merchant, 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 bicycles with bevelled gear have several disadvantages, the most important
of these is that the adjusting of the driving gears, especially of the front one, is
very difficult, and as a matter of fact, has to be left to the feeling of touch only.
In all hitherto used bicycles of this kind, the bevelled wheel on the pedal
crank axle, is scated beside the crank and the little bevelled wheel meshing
with it, does so on the side directed towards the midde line of the bicycle. At
the same time the disk of the former is formed as a ball race cone. The whole
being surrounded by a dust protecting case tightly joined to the frame, it is
clear that the working together of the toothed wheels cannot be observed. Also
access to the ball bearing of the pedal crank axle on the side where the toothed
wheels are seated is impossible. The bevelled pinion transferring the action of
the intermediate axle to the hind wheel meshes with the cone wheel joined with
the hind wheel on the side directed towards the pedal crank bearing. It is
clear without further explanation that, if the ball bearings in which the inter-
mediate axle revolves, are worn a little, pressure is exercised upon them in their
length direction by the tapered spaces of the toothed wheels. When such
occurs the hinder toothed pinion connected with the intermediate axle, is
pressed faster against that on the hind wheel and the driving becomes heavy
and a creaking noise occurs. A further disadvantage of the chainless bicycles
put into motion by bevelled wheels consists in the frame construction deviating
too much from that of bicycles with chain gear. Especially the junction of the
horizontal and the vertical hind wheel forks together and with the hind wheel
axle is less stable than in the other known frame construction being only
possible by means of a complicated shackle.
Then it may also be mentioned that in consequence of the lateral situation of
the bevelled wheel on the crank axle it is subject to uneven twisting strain and
further by the arrangement also on one side of the dust protecting case, the
centre of gravity of the bicycle is moved considerably out of the middle line.
All these disadvantages are removed by the construction forming the object
of the present application.
Fig. 1 of the annexed drawing is a plan view of the driving gear. Fig. 2 a
side view of the same enclosed. Fig. 3 an under view of the pedal crank bearing
without its cover. Fig. 4 the latter separately. Fig. 5 a vertical section through
the dust protecting case of the front gear.
On the pedal crank axle A near the middle line of the bicycle is a bevelled
wheel B so placed that its teeth turn outwards by means of a smaller wheel
working therein its rotation is transferred to a shaft D seated in the horizontal
fork tube of the hind wheel. On its hinder end a third bevelled wheel E is
arranged, which works in a fourth bevelled wheel F fixed on the hind wheel

page_text: hub. The bevelled wheels engage from the outside and on the side of wheel F
which is furthest away from the pedal crank bearing. By arranging the toothed
wheel B near the middle between the two pedal cranks lateral strains are
avoided. If by fast pedalling the shaft D is pushed rearwards the bevelled
wheel E is pushed as much out of F as C out of B. The working of the two
gears one with the other must therefore be always exactly uniform and without
wedging.
By the new arrangement it is also possible to join the horizontal back wheel
fork tube directly with the vertical one and to place the axle of the back wheel
at the point of junction of the two. By avoiding the now used joining shackle,
the junction is simpler and at the same time stronger. For this purpose the
vertical rear wheel fork tube ends in a hook encircling the horizontal rear wheel
fork tube which encloses the shaft E and which can be fastened by means of a
screw in the known manner.
On the inside the rear wheel axle is screwed into the said hook.
The connection of the vertical and horizontal rear wheel forks on the side
opposite the gearing is effected in any known manner.
The pedal crank bearing has a dust protecting case G for the front gear.
After taking away the lower closing cover G' one can readily observe the work-
ing together of the two toothed wheels see Fig. 3 and can regulate them by the
ball bearings H H. The weight of the toothed wheel D and the dust protecting
case is also by the new construction moved more towards the middle, avoiding
the tendency of the bicycle to run towards the more heavily weighted side.
The working of the rear gear can also be observed after taking away the dust
protecting shell I and it can be regulated independently from the toothed wheels
in any known manner.
The dust protecting case G forms now, as will be seen in Fig. 5, a part of the
frame. The exterior of the new bicycle will be more pleasing than than the
hitherto used chainless bicycles because G is arranged in the middle.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is:-
1. A bicycle in which the movement of the cranks is transferred to the
driving wheel by means of bevelled wheels wherein the bevelled wheel B is fitted
upon the pedal crank axle A near the middle between the two pedal cranks with
its toothing directed towards the outside and wherein the bevelled wheel E on
the shaft D in the horizontal back wheel fork tube G meshes with the bevelled
wheel F fast upon the nave of the back wheel on the side remote from the pedal
crank shaft, by which arrangement the one-sided working of the wheel bis
avoided and also the pinching of the rear gear E F and the direct fastening of
the back wheel axle at the junction of the horizontal and the vertical fork tubes
is rendered impossible.
2. In a bicycle as in Claim 1 the formation of the pedal crank bracket as a
dust protecting case for the bevelled gear.
Dated this 22nd day of November 1898.
HERBERT HADDAN & Co.,
Agents to Applicant. 18, Bucking im Street,