Improvements in and relating to Chainless Gearing for Cycles.
Year: 1899

page_text: Date of Application, 16th Sept., 189)-Accepted, 21st Oct.. 18,9
COMPLETE SPECIFICATION.
Improvements in and relating to Chainless Gearing for Cycles.
I, JOSEF MARZION, of, Mocker O/S, Prussia, in the German Empire, Inn
Keeper, 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:-
This invention relates to a type of chainless gearing for use with bicycles,
tricycles, and the like, and its object is to so construct and arrange such gearing
that it possesses no dead points.
A form of gearing actuated by two vertically reciprocating pedals and to which
these improvements are applicable, is illustrated in the accompanying drawings to
which I will hereinafter refer.
Figure 1 shows in elevation a bicycle to which the improved gearing is
attached.
Figure 2 shows in plan part of the driving wheel of the same machine.
Figures 3, 4, 5, 6, and 7 represent the driving mechanism and details of the
driving mechanism upon an enlarged scale.
As will be seen the driving wheel of the machine is driven from or by the
vertically reciprocating levers a, b, the ends of which are provided with suitable
pedals. The pedals are connected together by the cord, chain, or the like c
which passes over a suitable pulley in such a manner as to ensure that one pedal
is rising when the other is falling.
The inner ends or hubs of the levers a, b are formed into cases or boxes d
which contain a suitable number of spring controlled detents or ratchets e, capable
of moving within grooves or recesses p. The hubs d encircle the two toothed
wheels which are fixed to the axle f, and this axle also has secured to it a
toothed wheel h which gears with a pinion i mounted upon the frame of the
machine. Fixed to the pinion i is a second wheel which gears with a pinion
secured to the hub of the machine wheel.
The levers a are alternately pressed up and down to drive the machine, each
lever being effective when moving in one direction. When the hub d of a lever
moves in the direction shown by arrow in Figure 3 the wheel g is driven forward;
when it rotates in the direction shown by the arrow in Figure 4 it slips backwards
and the wheel g and axle f are driven forward by the other lever.
The pawls e within a hub d are shaped as shown and are controlled by springs n
whose normal tendency is to force them inwards against the teeth of the wheel g.
A greater number of pawls or detents e are employed than there are teeth in the
wheel g.
Referring to the driving device on one side of the machine only, and the
hub d being rotated with the arrow Figure 3, one of the teeth e engages with its
front face against the correspondingly shaped face of one of the teeth upon the
wheel g. The detent is thereby forced backwards as indicated by the dotted
arrow, Figure 3, so that a coned or wedge shaped part on its back face is forced
into and firmly held in a correspondingly shaped recess o formed in the channel p.
The detent is thus prevented from rising in its groove or channel and the wheel g
is carried forward.

page_text: When the hub d is revolved by the upward movement of the lever in the
opposite direction as indicated by the arrow in Figure 4 the detent e is moved
in the direction of the dotted arrow by the curved surface g of the tooth upon
the wheel until the front facer of the detent comes against the contiguous face
of the channel 7. The pawl e is now free to move upwards and allow the passage
underneath it of the tooth of the wheel g.
Owing to the greater number of detents employed than there are teeth in the
wheel it is ensured that detents at opposite ends of a diameter of the hub d are
always in similar engagement with the teeth.
or
s indicates a curved guide rail with which the pedal or the end of the lever a 1
may be engaged by rollers, bowls or the like.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is;-
In a chainless gear of the type described, a hub or casing upon the end of a
pedal lever, a toothed wheel surrounded by the hub or casing, and movable detents
contained within the hub and capable of engaging with the teeth of the wheel,
a greater number of detents being employed than there are teeth in the wheel,
all constructed and arranged substantially as and for the purpose hereinbefore
set forth and as illustrated by the accompanying drawings.
Dated this 15th day of September AD 1800
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