Improvements in Treddle Cranks for Bicycles and other Velocipedes.
Year: 1887

page_text: Date of Application, 17th Nov., 1887
Complete Left, 20th Mar., 1888
Complete Accepted, 20th Apr., 1888
Improvements in Treddle Cranks for Bicycles and other
Velocipedes.
•
1, FRANZ LOUIS RÖDEL of the firm of Rödel & Seidel Manufacturers of Elster-
berg V in the Empire of Germany do hereby declare the nature of this invention
to be as follows:-
This invention relates to the treddle cranks of bicycles and other velocipedes and
consists in certain improvements whereby the distance of the treddle from the crank
centre may be lengthened or shortened by the rider without dismounting or stopping
the travel of the velocipede.
The object of the invention is therefore to enable the velocipede to be propelled
with more or less power according to the gradients traversed.
The crank is for this purpose made in two sliding parts adapted to be secured in
an extended or contracted position by a spring catch adapted to arrive and engage
into corresponding holes in one of the parts. The one part is connected to the axle,
the other carries the treddle spindle-A suitablo bevelled plate is arranged to be
propelled by pressure of the foot of the rider, in such a manner as ride over and
loosen said spring catch when desired, for the setting of the crank in the desired
position-The said bevelled plate is normally held in an intermediate position by a
spring so as to lie out of action except when pressed by the foot.
Dated this 17th day of November 1887.
HERBERT & Co.,
Agents to Applicant.

page_text: Velocipedes.
I, FRANZ LOUIS RÖDEL, of the firm of Rödel and Seidel, of Elsterberg, 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 :-
This adjustable crank for bicycles and other velocipedes serves to enable the rider
to lengthen or shorten the crank during the riding. It consists essentially of
3 parts the stationary part or crank proper a fixed to the axle b of the wheel, the
part d movable on a and carrying the pedal on the crank pin e aud the slide k.
In the accompanying drawings
Fig. 1 represents a front elevation of the crank, the cover being removed. Fig. 2
is the slide k. Fig. 3 is the shortened crank in vertical section, Fig. 4 is the
lengthened crank in vertical section. Fig. 5 represents the adjustable plates I II
formed with recesses h h' and Fig. 6 is the arm g with the nose f.
The part a fixed to the axle 6 of the wheel carries the part d movable on a in the
guides c c. The crank pin e is screwed into the part d which also carries the slide k.
If the crank is shortened as in Fig. 3 and it is desired to lengthen it, the rider
places his foot on the head of the slide k as soon as it points upwards, and the
inclined side of the nose i of the slide k will press the arm pivotted to the part d
at g¹ on one side and the nosef of the arm g which passes through the slot f¹ in the
part d will be disengaged from the recess ³ of the plates I II fixed to a.
The fixed part a and the movable part d are thus disengaged from each other and
the latter will slide down on the former until the nose of the arm g is pressed into
the recess of the plates I 11 under the influence of the spring m.
When the crank is to be shortened again the rider presses his foot on the head r
of the slide k when the inclined side of the nose i of the slide k will press the
nose out of the recess h and the part d will be moved towards the axle of the wheel
until the nosef engages again with the recess h¹ thus reestablishing the rigid
connection of the parts a and d.
To vary the extent of this lengthening and shortening the plates I II which carry
the recesses h h¹ are adjustable one relatively to the other besides both being adjust-
able on the part a.
These plates III overlapping each other are connected by a pin III screwed into
the plate and passing through the slot IV of the plate II. The pin III passes
also through the slot V of the part a and is retained in position by the nut or head VI.
By this arrangement the relative position of the recesses h h¹ can be varied by varying
the relative position of the plates I II or varying the position of both plates together
on the part a. The nut or head VI is prevented from loosening itself by the
Screw VII.

page_text: 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 :-
1. A crank for bicycles and other velocipedes which is adjustable to various lengths
and characterized by the fixed part or crank a on the axle of the wheel the part d
movable on a and the slide k substantially as specified.
2. In an adjustable crank the arrangement for attaching the movable part d to the
stationary part a characterised by the nose of the arm g which is pivotted to the
part d and is under the influence of a spring and the recesses h h¹ of the plates I II
which are adjustable relatively to one another and on the part a substantially as
specified.
3. In an adjustable crank the arrangement for disengaging the parts a and d from
one another by the inclined sides of the nose of the slide k pressing the arm g
with its nosef to one side, substantially as specified.
W. P. THOMPSON & BOULT,
Agents.