Improved Means for Securing the Cranks of Cycles to their Axles.
Year: 1898

page_text: PROVIDIUNAL DIMITTUALION.
Improved Means for Securing the Cranks of Cycles to their Axles.
I, GEORGE BROUGHAM HUBERT AUSTIN, of No. 60, Armadale Road, Armadale,
in the Colony of Victoria, Architect, do hereby declare the nature of this invention
to be as follows:-
Hitherto it has been usual to secure the cranks of cycles by means of a cotter
passing through a hole in said cranks and through a transverse key-way in the
axle. These means for securing them are however inconvenient as they do not
admit of the crank being tightened up as desired and when it is necessary to
remove a crank from its axle there is a danger of unskilled or inexperienced
persons breaking the axle in their endeavours to force back the cotter.
According to my invention I dispense altogether with cotters and secure the
cranks upon their axles by forming the latter with a right and left screw thread,
the one being of practically the same diameter as the axle and being arranged to
fit a corresponding screw thread on the inside of the crank, which can thus be
screwed to the axle, whilst the other thread is formed upon a small projection of
the axle and is intended to receive a lock nut which can be arranged to fit
within a recess in the crank and can be screwed up sufficiently tight to prevent
the crank from coming unscrewed from off the spindle.
A washer may if
preferred be provided between the lock nut and the shoulder of the crank
and in lieu of said lock nut a small set screw having an opposite thread to that on
the crank spindle may be passed through the crank into the end of the spindle.
Dated this Fifteenth day of June One thousand eight hundred and ninety-
Improved Means for Securing the Cranks of Cycles to their Axles.
I. GEORGE BROUGHAM HUBERT AUSTIN, of No. 60, Armadale Road, Armadale,
in the Colony of Victoria, Architect, 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:-
Hitherto it has been usual to secure the cranks of eveles by means of a cotter

page_text: passing through a hole in said cranks and through a transverse key-way in the
axle. These means for securing them are however inconvenient as they do not
admit of the crank being tightened up as desired and when it is necessary to
remove a crank from its axle there is a danger of unskilled or inexperienced
persons breaking the axle in their endeavours to force back the cotter.
According to my invention I dispense altogether with cotters and secure the
cranks upon their axles by forming the latter with a right and left screw thread,
the one being of practically the same diameter as the axle and being arranged to
fit a corresponding screw thread on the inside of the crank, which can thus be
screwed to the axle whilst the other thread is formed upon a small projection of
the axle and is intended to receive a lock nut which can be arranged to fit
within a recess in the crank and can be screwed up sufficiently tight to prevent
the crank from coming unscrewed from off the spindle. A washer may, if
preferred, be provided between the lock nut and the shoulder of the crank.
In lieu of said lock nut a small set screw having an opposite thread to that on the
crank axle may be passed through the crank into the end of the spindle.
My invention will be readily understood on reference to the accompanying
drawings in which,―
Figure 1 is a sectional view of part of a cycle crank and axle illustrating my
improved means for adjustably securing the former upon the latter.
Figures 2 and 3 are similar views showing modifications of the invention.
A represents a crank and B the axle to which it is to be adjustably secured. The
ends of the axle are screw-threaded as illustrated at C and the correspondingly
threaded crank is screwed on to it as shown. The projecting part of the axle is of
smaller diameter than the main part and has threads D cut upon it in the reverse
direction to those on said main part. If these larger threads are right handed as
illustrated in Figure 1 then the smaller ones are made left handed and vice versa if
the larger ones are left handed the smaller ones will be right handed as illustrated
in Figure 2.
E represents the lock nut which is screwed upon the reduced part of the axle
whilst represents a washer which may be placed between said nut and the crank
and may be prevented from rotating if desired.
In Figure 3 G represents the set screw which is used in lieu of a lock nut its
threads being cut (like said nut) in the reverse direction to the external-threads C
on the axle but instead of engaging with reverse external screw threads D), it
engages with reverse internal screw threads as shewn, the result being the same as
in the former case.
It will be readily understood that the invention above described enables cranks
to be adjustably secured upon their axles without danger of working loose or of
being broken, bent or strained when being removed for the purpose of allowing
adjustment of the cones or cups in the bottom bracket, or otherwise.
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 axle (as B) having adjacent reverse screw threads (as CD) on
different diameters of each end of said axle, in combination with cranks (as A)
threaded to correspond with the threads (as C) on the larger diameter of the
axle, and a nut (as E) threaded to correspond with the threads (as D) on the
reduced diameter of the axle (and with or without a washer as F) for the purpose
of adjustably securing said cranks to the axle substantially as herein described
and explained and as illustrated in Figures 1 and 2 of the drawings.
2. A crank axle (as B) having external screw threads (as C) and reverse internal
screw threads on each end in combination with cranks (as A) threaded to correspond
with said external screw threads (as C) and a set screw (as G) threaded to

page_text: correspond with the reverse internal screw threads for the purpose of adjustably
securing said cranks to the axle substantially as herein described and explained
and as illustrated in Figure 3 of the drawings.
Dated this First day of March One thousand eight hundred and ninety-nine.
G. B. H. AUSTIN.
Edwards and Co.,
Chartered Patent Agents, 65 and 66, Chancery Lane, London,
Agents for the Applicant.