Improvements in and relating to Brakes for Velocipedes.
Year: 1897

page_text: Date of Application, 4th Jan., 1897-Accepted, 27th Mar., 1897
_ COMPLETE SPECIFICATION..
Improvements in and relating to Brakes for Velocipedes.
I, ROBERT HAMILTON CANFIELD, a citizen of the United States of America,
residing at 21 West Fourth-Street in the City-of-Corning, County of Steuben and
State of New York, one of the United States of America Assistant Superintendent
of Fall Brook Railway, 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 :-
My invention relates to that class of brakes in which the brake is thrown into
action by the operation of "back pedalling."
The object of the invention is to provide a simple, efficient and inexpensive brake
of the class referred to.
The invention consists in the construction and combination hereinafter described
and pointed out in the claims.
Referring to the drawings-
Figure is a sectional view showing a portion of the rear bicycle wheel, its
sprocket and axle, with my improved brake mechanism applied.
Figure 2 is a similar view, slightly modified.
Figure 3 is a side elevation thereof.
Figure 4 is a sectional view of a further modification in which the brake
mechanism is applied to the pedal shaft, its sprocket, and the box or bearing, and
Figure 5 is a longitudinal section through the rear bearing of a bicycle showing.
the brake surface integral with the sprocket wheel and the faces of the brake,
surfaces furnished with leather.
In Figures 1, 2, 3, N represents the rear end portion of a bicycle frame provided
with the usual fork or slot N¹ in which is mounted the rear axle P, on which
rotates the hub R of the rear wheel. The hub R is, provided at one end, adjacent
to its spoke flange, with a. coarse screw-thread R' and the sprocket wheel D has "
its bore threaded as at D' to correspond therewith, and is loose on this threaded
portion R' so that when the sprocket chain D applies power to the sprocket in a
direction to drive it forwardly, the sprocket will bind against the spoke, flange or
end of the hub and thereby cause the rear wheel to rotate with the sprocket, but.
when the rider resorts to "back pedalling," the chain will reverse its strain on the
sprocket wheel and cause it to rotate backwardly on the hub, and consequently.
move longitudinally along said hub towards the outer end thereof owing to the
coarse screw-threaded connection therewith. The outward movement of the
sprocket D along its hub is limited by a nut H and washer K, the latter in
Figure 1 being of rubber confined between the said nut H and a second washer K'.
C is a brake disk fixed to the outer face of the sprocket D to contact with a
stationary brake disk B when the sprocket is forced outwardly by back pedalling.
This stationary brake disk is provided with a central aperture for the free
passage of axle P. and with a lug B₁ which enters the slot or fork N' and holds
the disk B from rotation. An adjusting screw N¹ is extended rearwardly through
the frame and bears against the lug B' for adjusting the axle. Owing to the pitch
of the threads R¹ D the brake will be quickly applied and released, and the
operator's seuse of feeling will soon enable him to regulate the application of
the brake with nicety. The adjacent faces of the brake disks C B may either or
both be provided with leather, raw hide, or other suitable material if desired, as

page_text: In this
shown in Figures 1 and 5. The disk C may be secured to the sprocket wheel
as shown in Figure 1, or formed integral with the sprocket wheel, as shown in
Figure 5, or if desired the disk C may be omitted and the face of the sprocket
contact with the stationary braking surface B, as shown in Figure 2.
latter construction the inner face of the stationary braking surface or disk B is
provided with an annular channel b in which is fitted a ring B2 of leather or other
suitable material to contact with the friction face of the sprocket wheel. This
friction face or surface of the sprocket D may be formed in any desired manner,
just so long as the principle is preserved of having the sprocket act as a brake
during back pedalling, by moving laterally along the hub into engagement with a
fixed or stationary friction surface, whether the same be applied to or formed
as an integral part of the frame. O is the usual nut on the outer end of the axle.
Referring now to Figure 4, it will be seen that the principle involved may be
readily applied to the pedal sprocket and adjacent parts. In this figure A
represents the stationary box or bearing for the pedal shaft E, and B is the
stationary friction surface consisting of a ring or flange secured to or formed on
the end of the box or bearing. The pedal shaft is provided with the coarse screw
threads E on which the driving sprocket D2 turns and slides after the manner of
the rear sprocket D on its hub, as when the pedalling is forward the sprocket
wheel will move outward, bind on the shoulder E2 and turn with shaft E, but when
back pedalling is resorted to, the sprocket wheel D2 will move inwardly along its
shaft into engagement with the stationary friction surface B³. The sprocket D'
may contact directly with surface B³ or indirectly through the medium of a
ring C¹ of any suitable material. His a stop nut or ring on the axle E to limit
the movement of the sprocket wheel D² towards the stationary surface B³, and K
is a washer, in the form of a cushioning spring interposed between the nut H' and
the sprocket wheel to cushion the movement of the sprocket towards said stationary
surface. F is one of the crank arms of the pedal shaft.
In Figure 5 I have shown a longitudinal section through the rear sprocket wheel
and its bearing in which it will be seen that the sprocket wheel has the bearing
disk C formed integral therewith, and in which it will be further seen that the
faces of the two braking surfaces, that carried by the sprocket wheel and the fixed
surface B, are provided with a facing of leather or other suitable material B¹.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. In a bicycle provided with a brake surface two rotating members mounted
adjacent thereto, and connected together by a screw thread, whereby a rotary
movement of one member relative to the other member operates to move one of
them laterally into contact with the brake surface.
2. The combination in a bicycle or analogous machine with the frame, of a
stationary brake surface fixed thereto, a rotary shaft mounted therein and provided
with external screw threads, a sprocket wheel threaded internally to fit the threads
on the shaft, a braking surface fixed to said sprocket wheel, and suitable
connections between the rotary shaft and the driving devices; whereby the action
of front pedalling will cause the sprocket wheel to turn with the shaft and separate
the brake surfaces, and whereby the action of back pedalling will cause the
sprocket wheel to move along the shaft longitudinally and contact with the
stationary brake surface.
3. The combination in a bicycle or analogous machine with the frame, of a
stationary brake surface fixed thereto, a rotary shaft mounted therein and provided
with external screw-threads, a brake wheel threaded internally to fit the threads
on the shaft and suitable connections between the rotary shaft and the driving
devices; whereby the brake wheel will be moved respectively to and from the
fixed brake surface by the action of back and forward pedalling.
4. The combination in a bicycle, of a rear driving wheel formed with a hub

page_text: having near one end external screw threads, a stationary brake surface fixed to the
frame adjacent to the threaded end of said hub and a sprocket wheel threaded
internally to fit the threads on the hub and provided with a brake surface adapted
to co-act with the stationary brake surface; whereby the forward rotation of the
driving devices will cause the sprocket wheel to move with the hub and separate
the brake surfaces, and whereby the reverse. motion of the driving devices will
cause the sprocket wheel to advance along the hub and apply the brake.
5. The combination with the bicycle frame having the usual rear slot in which
is mounted the rear axle, the rear wheel having its hub mounted on said axle and
provided at one end with external screw threads, and the loose, laterally movable
brake-forming sprocket wheel threaded to fit the hub thread, of a stationary
brake-disk apertured for the free passage of the axle and having a lug entering
the said frame slot to prevent said disk from turning, substantially as set forth.
6. The combination with the bicycle frame having the usual rear slot in which
is mounted the rear axle, the rear bicycle wheel having its hub mounted on said
axle and provided with coarse external screw threads adjacent to the spoke flange,
and provided with finer threads therebeyond, of the loose, laterally movable
brake-forming sprocket wheel threaded to fit said coarse threads, an adjustable nut
on the finer threads to limit the outward movement of said sprocket, and a stationary
brake disk having an aperture for the free passage of the axle and means for
locking it against rotation, substantially as set forth.
Dated this 4th day of January 1897
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.