An Improvement in or connected with Back-pedalling Brakes for Velocipedes or Cycles.
Year: 1898

page_text: [Communicated from abroad by LINFRID LARDNER WILLIAMS, of Wyncote,
Pennsylvania, in the United States of America, Engineer.]
An Improvement in or connected with Back-pedalling Brakes for
Velocipedes or Cycles.
I, JAMES HEWLETT, of 26, Ethelbert Road, Margate, in the County of Kent,
Chemist, do hereby declare the nature of this invention to be as follows:-
An improvements in or connected with back-pedalling brakes for velocipedes
or cycles consisting of the combination with the hub of the driving wheel and a
plate to be secured to the frame of the velocipede or cycle, of a shell secured to
said hub and having a flange provided with elongated slots, pawls carried by said
flange, a sprocket wheel, cams carried by the sprocket wheel and adapted to force
the pawls into contact with said plate when back pressure is applied to said
sprocket wheel, shoulders on the cams adapted to be engaged by the pawls when
forward pressure is exerted whereby to revolve the driving wheel, and screws
or pins secured to said cams and projecting through said elongated slots in the
flange on the shell so as to have frictional contact with the walls of said slots
and thus retain the pawls in contact with said plate should the driving chain of
the machine break when the brake is applied.
Dated this First day of November 1908
JAMES HEWLETT,
Chemist, 20, Ethelbert Road, Margate.
An Improvement in or connected with Back-pedalling Brakes for
Velocipedes or Cycles.
I, JAMES HEWLETT, of 20, Ethelbert Road, Margate, in the County of Kent,
Chemist, do hereby declare the nature of this invention a communication to me
from abroad by Linfrid, Lardner Williams, of Wyncote, Pennsylvania, in the
United States of America, Engineer, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement;
-
This invention relates to an improvement in brakes, and more particularly to

page_text: such as are adapted for use with bicycles and tricycles, the object of the inven-
tion being to provide means whereby to produce a simple, efficient, and light
brake adapted to be thrown into action by back-pedalling.
A further object is to produce a bicycle brake which shall be simple and compact
in construction and which shall be effectual in all respects in the performance
of its functions.
With these objects in view the invention consists in certain novel features of
construction and combinations and arrangements of parts, as hereinafter set forth,
and pointed out in the claims. In the accompanying drawings Figure 1 is a
sectional view illustrating my improvements. Figures 2 and 3 are sectional
views. A represents the hub of a bicycle or tricycle wheel having screw-threaded
portions 12, and B represents a sleeve or shell having an internal screw-threaded
Hange 3, for the reception of the screw-threaded portion 1 of the
hub. An annular jam-nut 4 is adapted to enter the sleeve or shell B
and screw upon the threaded portion 2 of the hub, the portion of the
hub and the flange 3 of the shell being provided with right hand threads and
the portion 2 of the hub and the nut 4 being provided with left hand threads,
and thus the sleeve or shell B is secured to the hub of the driving wheel of the
machine.
The sleeve or shell B is provided at one end with an annular flange 5, and a
short distance from said flange an annular disc or rim 6 is disposed, said flange
and ring or disc being secured together (but spaced apart) by means of suitable
pins or rivets.
A sleeve. or ring 7 is revolubly mounted on the sleeve or shell B,
and a portion of this revoluble sleeve or ring is provided with an annular series
of teeth or projections whereby to form a sprocket wheel S.
The revoluble sleeve or ring 7, is provided with two (more or less) flanges 9,
having cam faces 10, and each having a tooth or shoulder 11, at one end, said
flanges being adapted to project into the space between the flange 5, of shell B
and the ring or disc 6. Between the flange 5 and ring 6, and beyond the peri-
pheral cam-faces of the flanges 9, pawls 12 are pivotally connected, said pawls
corresponding in number to the number of cam faces employed, and each pawl
is provided at its free end with a tooth to engage the respective teeth or
shoulders 11 at the ends of said cam-faces, so that when the sprocket wheel is
driven forwardly it will be locked to the shell B, and thus result in revolving
the driving wheel of the machine. Springs 12" press the pawls against the cam-
faces.
A disc 13 is secured to the frame of the machine in close proximity to the
shell B and is provided with a peripheral flange 14 to embrace the flange 5 and
the ring 6.
From this construction and arrangement of parts it will be seen that when
back pressure, as in back-pedalling, is applied to the sprocket wheel the ring or
sleeve 7 will be made to turn backwardly independently of the shell B, so as to
cause the cam-faces to operate to force the pawls outwardly into contact with
the peripheral flange 14 of disc 13, and thus by frictional contact therewith
result in braking the machine.
The flange of shell B is provided with two (more or less) elongated slots 15,
through which screws 16, secured to the cam flanges, project, and in which said
screws have just sufficient frictional resistance to keep the cams in proper position
should the driving chain break while the machine is running down-hill. Thus it
will be seen that when the brake is applied it will not be released should the
chain break.
My improvements are simple in construction and are effectual in all respects
in the performance of their functions.
Various slight changes might be made in the details of construction of my
invention without departing from the spirit thereof or limiting its scope, and
hence I do not wish to limit myself to the precise details herein set forth.

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. In a velocipede, the combination with the driving wheel and a plate adapted
to or secured to the frame of the machine, of a sprocket wheel, a cam carried by
the sprocket wheel, pawls connected with the driving wheel and adapted to be
forced against said plate by said cam and shoulders at the ends of the cams to
be engaged by said pawls when forward pressure is applied to the sprocket to
propel the machine, substantially as set forth.
2. The combination with the hub of a driving wheel and a plate to be secured
to the frame of a velocipede, of a sleeve or shell secured to said hub, pawls
pivotally connected to said sleeve or shell, a sprocket wheel, cams carried by said
sprocket wheel and each having a shoulder at one end to be engaged by the ends
of the pawls when the sprocket wheel is driven forwardly, said cams being adapted
to force said pawls against said plate when back pressure is applied to the sprocket
wheel in back-pedalling, substantially as set forth.
3. The combination with the hub of a wheel having right and left hand screw
threads thereon and a plate adapted to be secured to the frame of a velocipede,
of a shell adapted to screw on said hub, a jam-nut adapted to enter said shell and
serew on to said hub, pawls carried by said shell, a sprocket-wheel and cams
carried by the sprocket wheel and adapted to force said pawls against said plate
when back pressure is applied to said sprocket wheel, said cams each having a
shoulder thereon which is engaged by the end of one of the pawls so that when
the sprocket wheel is driven forwardly it will revolve the wheel, substantially,
as set forth.
4. The combination with the hub of a driving wheel and a plate adapted to be
secured to the frame of a velocipede, of a shell secured to said hub, a flange on
said shell, a ring surrounding a shell and connected with said flange, pawls pivot-
ally attached between said flange and ring, a sprocket wheel mounted on said shell,
cams carried by said sprocket wheel and disposed between said flange and ring,
said cams adapted to force the pawls against the said plate when back pressure is
applied to the sprocket wheel, springs forcing said pawls against the cams and
a shoulder at one end of each of said cams to be engaged by the free ends of the
pawls, substantially as and for the purpose set forth.
5. The combination with the hub of the driving wheel and a plate to be secured
to the frame of a velocipede, of a shell secured to said hub and having a flange
provided with elongated slots, pawls carried by said flange, a sprocket wheel,
cams carried by the sprocket wheel and adapted to force the pawls into contact
with said plate when back pressure is applied to said sprocket wheel, shoulders
on the camis adapted to be engaged by the pawls when forward pressure is exerted
whereby to revolve the driving wheel, and screws or pins secured to said cams and
projecting through said elongated slots in the flange on the shell so as to have
frictional contact with the walls of said slots and thus retain the pawls in contact
with said plate should the driving chain of the machine break when the brake is
applied, substantially as set forth.