Improved Driving Mechanism and Brake for Bicycles.
Year: 1897

page_text: Date of Application, 23rd Nov., 1897-Accepted, 22nd Jan., 1898
COMPLETE SPECIFICATION.
Improved Driving Mechanism and Brake for Bicycles.
I, JOHN JACOB LA BURT, of Van Wyck Avenue, Jamaica, Long Island, Queens
County, State of New York, United States of America, Machinist, do hereby declare
the nature of my 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 improvements in bicycle driving mechanism and a brake,
and the object is to provide a simple mechanism for the above purpose that may
be easily applied to any of the well known make of bicycles at a comparatively
small expense, and by the use of which the bicycle shall be allowed to proceed
while the pedal shaft is held stationary by the feet of a rider, thus adding to the
comfort and ease of a rider while coasting, and further by means of which the
brake may be instantly applied by a slight back pressure on the pedals thus lessen-
ing the dangers incident to coasting and fast riding.
I will describe a mechanism embodying my invention and then point out the
novel features in the appended claims.
'
In the accompanying drawing, Figure 1 is a side elevation of a portion of a
bicycle showing my invention as applied thereto. Figure 2 is a plan view of a
crank hanger and showing the driving mechanism in section. Figure 3 is a
section on the line 3-3 of Figure 1. Figure 4 is an inside view of the driving
mechanism. Figure 5 is an elevation of a brake actuating ring employed.
Figure 6 shows a retaining ring employed and Figure 7 is an outside view of a
sprocket ring carrier and the dog carrying disk.
In carrying out my invention I attach a disk 1 rigidly to the crank shaft 2.
This disk is provided at its inner side with a peripheral annular flange 3, and at
its outer side it is provided with an annular shoulder 4 against which the inner
periphery of a holding ring 5 engages. The flange 3 and the ring 5 form the side
walls of a raceway for a sprocket ring carrier 6 mounted to rotate, under certain
conditions with the disk 1, and at other times to rotate freely on the disk all as will
he hereinafter described. The carrier 6 is provided with radial lugs 7 to which
the short spokes of the sprocket toothed ring 8 are designed to be attached. From
this sprocket ring the chain 9 extends to the sprocket on the rear wheel axle.
Mounted on the inner side of the disk 1 is a dog 10. This dog 10 has a lug 11
designed to pass through an opening in the rim of the disk to engage in either one
of the notches 12 formed at intervals in the inner periphery of the carrier 6. This
dog is fulcrumed to swing radially and it is forced vieldingly outward by means
of a spring 13, secured to the disk 1, and bearing at its free end against the inner
side of the dog.
Surrounding the pedal shaft 2 and engaging the inner side of the disk 1 is the
brake actuating ring 14, having a series of ratchet teeth 15 on its inner side
designed to be engaged by an inwardly movable dog 16, pivoted to the disk 1, when
it is desired to apply the brake to be described. This dog 16 has a finger 17
extended from its free end and engaging with the outer side of a finger 18 extended
from the free end of the dog 10 and the said dog 16 may be turned inward by
means of a spring 19 secured to the disk 1 and bearing at its free end against the

page_text: inner edge of the dog 16 rearward of its pivotal point. The pressure of the
spring 13 on the dog 10 is somewhat greater than the pressure of the spring 19
on its dog therefore the dog 16 will be held normally outward by the dog 10 but
when a back pressure is put upon the pedals the lug 11 of the dog 10 will ride
upon the inner surface of the support 6, between its notches 12, and as the dog 10
is thus forced inward the end of the dog 16 will be moved by the spring 19 into
engagement with one of the teeth 15.
The brake comprises a yoke 20 mounted on a rod 21 having bearings in lugs
attached to the frame members extending from the shaft hanger to the rear wheel
hanger. This yoke, with its brake shoe, is held normally away from the rear wheel
tire by means of a spring or springs 22, secured at one end to the rod 21 and at
the other end bearing upon the frame members. Mounted in the upper portion
of the yoke 20 is a roller 23, and extended across the lower portion of the yoke
is a rod 24 from which a guide plate 25 extends upward. Extending around the
roller 23 and the rod 24 and also bearing against the plate 25 is a brake shoe 26,
in the form of an endless band and consisting of flexible material such, for
instance, as rubber. When this brake shoe is pressed against the wheel tire the
said shoe will be caused to move rotatively until the wheel comes to a stop and
owing to this movement it is obvious that no damage can result to the tire by
abrasion as would be the case were the brake shoe fixed in the yoke. From the
yoke 20 a link 27 extends to a pivotal connection with a lug on the actuating
ring 14, so that when said ring is rotated slightly in a rearward direction the
brake shoe will be forced against the wheel tire.
To provide for an easy movement of the disk 1 relatively to the ring 14 I may
employ anti-friction balls seated in raceways formed in the ring 14 and the disk 1
as plainly shown in Figure 2.
In operation, when the pedals are operated to move the bicycle forwards the
lug 11 of the dog 10 by engaging in one of the notches 12 will cause the carrier 6
to move with the shaft and thus impart motion, through the sprocket chain, to
the rear wheel. Upon descending hill or coasting the pedals may be held stationary
and then the carrier may rotate on the disk, which, of course, is held with the
pedals and shaft. At this time the dog 16 will be moved into the line of movement
of the ratchet teeth 15 so that upon back pedalling the ring 14 will be rotated
sufficiently to apply the brake.
When it is desired to secure the carrier 6 to the disk 1, a pin 28, movable in a
socket 29 on the ring 5 may be pushed into a hole 30 in the dog 10, thus holding
he dog in engagement with the carrier.
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. A bicycle driving gear, comprising a pedal shaft, a disk secured thereto, a
sprocket carrier mounted to rotate on the disk and a spring pressed dog for engag-
ing the carrier with the disk.
2. A bicycle driving gear, comprising a disk mounted on the pedal shaft, a
sprocket carrier mounted to rotate on the disk and means for causing the carrier
to rotate with the disk.
3. A bicycle driving gear comprising a disk mounted on the pedal shaft, a
keeper ring detachably secured to the disk, a sprocket carrier mounted to rotate
on the disk and a spring pressed dog on the disk and adapted to engage in a notch
of the carrier.
4. A bicycle driving gear, comprising a disk mounted on the pedal shaft, a
sprocket carrier mounted to rotate on the disk, means for causing the carrier to
rotate with the disk, a brake actuating ring supported by the disk, means for rotat-
ing the ring upon a backward movement of the disk, a brake and a connection
between the brake and ring.
5. A bicycle driving gear, comprising a disk mounted on the pedal shaft, a

page_text: sprocket carrier on the disk, a ring carried by the disk, a dog pivoted on the disk
and adapted to engage with ratchet teeth on the ring, a brake, and a connection
between the brake and ring.
6. A brake for a bicycle, comprising a yoke having swinging connection with
the bicycle frame, and a shoe mounted to rotate in the yoke when brought in con-
tact with a wheel of a bicycle.
7. The combination with bicycle driving gear, substantially such as described,
of a brake comprising a spring pressed yoke, a brake shoe mounted to rotate in
the yoke and consisting of an endless band and means operated by the driving gear
to force the shoe against the wheel of a bicycle.
8. A driving gear for a bicycle comprising a disk mounted on the pedal shaft,
a sprocket carrier mounted to rotate on the disk, a yielding connection between
the disk and carrier and means for rigidly connecting the carrier to the disk.
Dated this 22nd day of November 1897.
W. D. FITZPATRICK,
70, Wellington Street, Glasgow, Agent.