Improved Driving Gear for Cycles.
Year: 1897

page_text: Date of Application, 23rd June, 1897-Accepted, 18th June, 1898
Improved Driving Gear for Cycles.
i
I WILHELM DIDAM, of 3, Herrschelstrasse, Hanover, in the German Empire,
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 driving gear for cycles with levers and
gearing. Many attempts have been made to replace the usual chain gearing of
cycles by another mechanism which will obviate the drawbacks of the present
arrangement, but no really serviceable substituto has so far been invented."
My invention is designed to effect this improvement and actuates, by maens of
a gearing and lever, a gear wheel secured upon the wheel axle, and thus drives the
wheel itself.
By means of my gearing, and in contrast to the gear hitherto in use the power
applied by the rider is applied as slowly as possible, and approximately in a straight
line so that the same effects the driving of the cycle at any desired speed directly
without the aid of further intermediate gearing, and by means of the two above
named elements.
Referring to the accompanying drawings in which
Figure 1 represents a view of a cycle provided with my gear.
Figures 2, 3, 4, 5, and 6 are detail views of portions of the said gearing.
As shewn in Figure 2 the toothed wheel 6 is firmly connected with the axle upon
which is placed the driving wheel of the cycle 5 (see Figure 1). The bolt forming
the pivot 1 of the levers 2 is fixed on the frame of the cycle. In order to enable
the racks to engage alternately with the wheel 6, and thus keep the wheel 5 in
continuous rotation-in one direction, the treadle levers 2 are slotted (Fig. 1) and
move alternately backwards and forwards at each stroke.
When the lever 2 revolves on its centre of revolution 1 the gearing 4, which is
fastened to the lever 2 and engages with the gear wheel 6, actuates the said wheel
and thereby revolves the driving wheel 5 of the cycle. In order to maintain the
gearing 4 and the gear wheel 6 in uninterrupted contact the former is guided by
means of its slot 7 upon its bolt 8 of the axis of the cycle driving wheel 5. The
end of the lever in which the gear wheel 6 shall engage (said wheel being firmly
fixed on the wheel axle) may be formed as a rack gear of various shapes capable of
engaging in the gear wheel 6, as illustrated for instance in the arrangements of
the gear 4 shewn in the various figures. By means of this arrangement the power
supplied by the rider is conveyed through the lever 2 and further through the
special shaped gearing 4 in the longest and straightest manner, consequently in
the most advantageous manner, directly to the driving wheel 5 of the cycle. The
gearing 4 can be provided with outer or inner teeth, and may be shaped in the
form of a flattened elliptic or circular shape, as shewn in Figures 1 to 6.
Figure 1 shows a view of the aforesaid gearing as applied to both sides of the
cycle driving wheel 5.
Figure 2 shews a view together with a section through the gearing 4, gear
wheel 6, aud guiding slot 7 for the bolt 8 of the axis of the cycle driving wheel.

page_text: Figure 3 shews a flattened gearing with outer teeth.
Figure 4 shews a similar gearing with peg teeth.
Figures 1, 5, and 6, shew the gearing in the form similar to that of an ellipse,
and moreover Figure 1 shews peg toothing, Figure 5 outer toothing, and Figure 6
inner toothing.
In contradistinction to the usual methods of driving cycles as at present in use,
and also, in contrast to all other known methods my invention possesses the
following important advantages. The doing away with the crank axle chain and
chain wheels. Moreover removal of the hitherto necessary intermediate gearings
for the purpose of obtaining suitable speed: considerable reduction in the weight
of the cycle in consequence of the reduction of the number of the working parts
hitherto necessary: reduction of the friction to a very trifling minimum, and in
consequence thereof greater speed with less consumption of power: finally the
possibility of riding both forwards and backwards. In consequence of their special
position with regard to one another the two toothed gearings are arranged to over-
take one another, and can consequently never simultaneously remain standing at
their dead points when uncontrolled, and are consequently always in a position for
driving.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. A driving mechanism for cycles characterized by a sliding mechanism;actuated
by means of two armed levers with a toothing around it for the purpose of driving
a gear wheel fixed upon the axle of the driving wheel.
2. A modification of the driving mechanism set forth in Claim 1 in which the
sliding part actuated by the lever sideways above or below the driving mechanism
and working horizontally is provided with outer, inner, or peg toothing.
3: A modification of the mechanism set forth in Claim 1 in which a lever 2
turns upon a fixed point 1 secured to the frame of the cycle, in which frame a
toothed gear 4 is arranged, which by the action of the lever 2 drives the toothed
wheel 6, and thereby actuates the cycle driving wheel 5 directly in any desired
ratio of transmission, substantially as described.
Dated the 2 brú day of June 1991.
June
W. P. THOMPSON & Co.,
Of London, Liverpool, Manchester and Birmingham,
Patent Agents for the Applicant.