Certain Improvements in Automatic Brakes for Safety Bicycles and other Velocipedes and Motor Carriages.
Year: 1896

page_text: PROVISIONAL SPECIFICATION.
Certain Improvements in Automatic Brakes for Safety Bicycles and
other Velocipedes and Motor Carriages.
We, JAMES WARD MILLIGAN, of 36, Lancaster Street, in the City of Birmingham,
Director and Secretary of Perry and Company Limited, and FRED OLDFIELD, of
36, Lancaster Street, aforesaid, Works Manager of the said Company, do hereby
declare the nature of this Invention to be as follows:-
This invention has reference to automatic brakes of that kind which in some
safety bicycles or other velocipedes are used upon the crank axle or driving chain,
in combination with the sprocket wheel of the driving chain, the brake being
so arranged that when the crank axle or driving axle is turning in the
direction to propel the bicycle or other velocipede forwards the brake is
out of action, but immediately the rotary movement of the sprocket wheel exceeds
the rotary movement of the crank axle or driving axle, as when the bicycle or
other velocipede is running down hill and the rider is back pedalling or at other
times when the rider is back pedalling, the brake automatically comes into action,
and on the rotary movement of the crank axle or driving axle exceeding the
rotary movement of the sprocket wheel the brake is automatically thrown out of
action.
This Invention consists of the hereindescribed improved construction and
arrangement of the parts whereby the brake is simplified and is rendered very
effective.
We will describe this Invention as applied on the crank axle of a safety bicycle.
In carrying out this Invention we provide a metal disc fixed to the bottom
bracket which carries the drank axle this disc having fixed on its face next to the
sprocket wheel a disc of leather or other suitable material to give a frictional
surface. The boss of the sprocket wheel is screw threaded and fits upon a screw
threaded part formed on the boss of the crank or on the crank axle so that the
sprocket wheel has a limited movement along the crank axle this movement
being limited in one direction by the face of the sprocket wheel coming in contact
with the said fixed frictional disc, and in the other direction by the face of the
boss of the sprocket wheel coming in contact with the face of a collar formed on
the crank. A suitable spring is or may be employed to tend to keep the sprocket
wheel pressed away from the frictional disc and in contact with the face of the
boss of the crank.
The brake above described acts as follows:-When the rider is pedalling forward
the brake is out of action as the turning of the crank in that direction screws
the sprocket wheel away from the frictional disc and against the face of the collar
on the boss of the crank. Immediately the rider back pedals the tightening of
the bottom portion of the driving chain screws the sprocket wheel against the fixed
frictional disc and thus the friction set up between the said disc and the face of
the sprocket wheel forms the brake. The said spring causes the brake to be

page_text: applied gradually as it prevents the sprocket wheel from becoming jambed too
tightly against the frictional disc.
The leather or other frictional surface may if preferred be fixed to the face of
the sprocket wheel to bear against the fixed disc instead of vice versa as above
described.
The said spring (when used) may be so arranged that its tension can be adjusted
by a screw or by other means so that it requires a greater or smaller amount of
back pressure on the pedals to bring the brake into action according to the re-
quirements of the rider.
The frictional surfaces of the--sprocket wheel and disc may be made with in-
clined concentric grooves or be otherwise formed to increase their frictional hold.
Instead of the movement of the sprocket wheel in the direction of the axis
of the crank axle to put the brake "on" or "off" being obtained by screw threads
as above described, the same effect may be obtained by providing inclined surfaces
on the sprocket wheel and boss or other part of the crank.
Dated this 18th day of September 1896.
יו
. CHARLES BOSWORTH KETLEY,
Agent for the Applicants.
Certain Improvements in Automatic Brakes for Safety Bicycles and
other Velocipedes and Motor Carriages.
We, JAMES WARD MILLIGAN, of 36, Lancaster Street, in the City of Birmingham,
Director and Secretary of Perry & Company Limited, and l'RED OLDFIELD, of
36, Lancaster Street, aforesaid, Works Manager to the said Company,. 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 has reference to automatic brakes of that kind which in some
safety bicycles or other velocipedes are used upon the crank axle or driving axle
in combination with the sprocket wheel of the driving chain, the brake being
80 arranged that when the crank axle or driving axle is turning in the
direction to propel the bicycle or other velocipede forwards the brake. is
out of action, but immediately the rotary movement of the sprocket wheel exceeds
the rotary movement of the crank axle or driving axle, as when the bicycle or
other velocipede is running down hill and the rider is back pedalling or at other
times when the rider is back pedalling, the brake automatically comes into action,
and on the rotary movement of the crank axle or driving axle exceeding the
rotary movement of the sprocket wheel the brake is automatically thrown out of
action.
This Invention consists of the herein described improved construction' and
arrangement of the parts whereby the brake is simplified and is rendered very
effective.
We will describe this Invention by referring to the accompanying drawings
which illustrate a brake, constructed according to this Invention applied on the
crank, axle of a safety bicycle. Fig. 1 is a plan of the bottom bracket with the
cranks and crank axle and sprocket wheels of a safety bicycle with our Invention
applied the sprocket wheel being in the position which it occupies when the
brake is "off"; Fig. 2 shews the same, parts as Fig. 1 with the sprocket wheel
in the position which it occupies when the brake is "on"; Fig. 3 is a back

page_text: elevation and Fig. 4 is a sectional plan of the sprocket wheel separately; Fig. 5
is a separate front view and sectional elevation of the friction disc which is fixed
to the bottom bracket; Fig. 6 shows the crank separately and Fig. 7 is a side view
of the crank and sprocket wheel shewing how we may employ a spring in com-
bination with our improved brake.
The same letters of reference indicate the same or corresponding parts in all
the figures of the drawings.
In carrying out this Invention we provide a metal disc A which is fixed to the
bottom bracket B which carries the crank axle C, this disc A having fixed on its
face next to the sprocket wheel D) a disc E of leather or other suitable material to
give a frictional surface. The dise A can readily be fixed as hy being screwed
on to the cone 6 of the ball bearing. The boss d' of the sprocket wheel D is
screwed (preferably a double square thread as shown) and fits upon a screw
threaded part f¹ formed on the boss of the crank F (or the screw threaded part may
be formed on the crank C) so that the sprocket wheel D has a limited movement
along the screwed part f¹ this movement being limited in one direction by the face
of the boss of the sprocket wheel D coming in contact with the frictional
disc E and in the other direction by the face of the boss d of the sprocket
wheel D coming in contact with the face of a collar formed on the crank F.
A suitable spring is or may be employed to tend to keep the sprocket wheel D
pressed away from the frictional disc E and in contact with the face of the
hoss f of the crank F. Such a spring for instance as the spiral spring G shewn
in Fig. 7 which is arranged on the curved arm or sector H fixed to the sprocket
wheel D which arm or sector is made to slide in a hole f3 formed in the end of
the arm f forming a part of the crank F.
The brake above described acts as follows:-When the rider is pedalling for-
ward the brake is out of action as the turning of the crank in that direction
screws the sprocket wheel D away from the frictional disc E and against the face
of the collar on the hoss of the crank F. Immediately the rider back pedals,
the tightening of the bottom portion of the driving chain screws the sprocket
wheel D against the fixed frictional disc E and thus the friction set up between
the disc E and the face of the hoss of the sprocket wheel D forms the brake.
The spring above referred to (such for instance as the spiral spring G) causes
the brake to he applied gradually as it prevents the sprocket wheel D from be-
coming inmhed too suddenly or too tightly against the frictional dise E.
The leather or other frictional surface E may if preferred be fixed to the face
of the boss d of the sprocket wheel to bear against the fixed disc A instead of
vice versa as above described. The frictional surface of the sprocket wheel D
and of the disc A may be made with inclined concentric grooves or be otherwise
formed to increase their frictional hold.
The said spring G or other spring when used may be so arranged that its
pressure can be adjusted by a screw or other means so that it will require a greater
or smaller amount of back pressure on the pedals to bring the brake into action
according to the requirements of the rider. This adjustment of the spring G can
readily be accomplished by providing an adjustable collar h¹ on the curved arm
or sector H which by the set screw hª can be fixed at any desired position on the
arm or sector H to give the desired compression of the spring G.
The accompanying drawings illustrate what we consider the best way for
carrying our Invention into practice but it is to be understood that our Invention
is not limited to the precise details shewn.
Having now particularly described and ascertained the nature of our said
Invention, and in what manner the same is to be performed, we declare that
what we claim is:-
1. In brake mechanism for chain and sprocket wheel driven bicycles and other
velocipedes mounting the sprocket wheel on a screw thread on the crank boss.
or axle in combination with a frictional surface on the face of the sprocket wheel

page_text: and a fixed frictional surface on the face of the bottom bracket or bearing so
arranged that when the rotary movement of the sprocket wheel exceeds that of its
axle the frictional surfaces are brought into contact and the axle retarded and
when the rotary movement of the axle exceeds that of the sprocket wheel the
brake surfaces are moved out of contact and the axle is free, substantially as
described.
2. Brake mechanism for chain and sprocket wheel driven bicycles and other
velocipedes arranged and operating substantially as hereinbefore described and
illustrated by the accompanying drawings.
3. The combination with brake mechanism of the kind denoted under Claim 1
of a spring arranged to tend to separate the break surfaces for the purposes and
substantially as herein before set forth.
Dated this 16th day of July 1897.
CHARLES BOSWORTH KETLEY,
Agent for the Applicants.