Improvements in Brake Mechanisms for Bicycles and similar Vehicles.
Year: 1898

page_text: Date of Application, 3rd May, 1898-Accepted, 15th Oct., 1898
COMPLETE SPECIFICATION.
Improvements in Brake Mechanisms for Bicycles and similar
Vehicles.
I, SILAS FADER, a citizen of the Dominion of Canada, residing at Vancouver,
in the Province of British Columbia, Canada, Gentleman, 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 relates to improvements in that class of brake mechanisms for
bicycles and similar vehicles operated by back-pedalling, and it has for its object
to provide a brake mechanism of this character of a very simple nature,
economically manufactured which can be readily applied to ordinary makes of
bicycles and which will effectively serve for its intended purposes.
The invention consists in certain construction and combination of parts which
will be first described and then pointed out in the appended claims, reference
being had to the accompanying drawing, in which:-
Fig. 1 is a side elevation of a portion of a bicycle with my improvements
applied.
Fig. 2 is a rear elevation illustrating the axle and hub of the drive wheel, the
sprocket brake disk plate and its frame connecting devices.
Fig. 3 is a longitudinal section of the parts shown in Fig. 2, the sprocket
wheel being shown in its normal position.
Fig. 4 is a similar view illustrating the parts in their brakeing position.
Fig. 5 is a detail view of the disk plate.
Figs. 6, 7, and 8, illustrate respectively a portion of the drive axle, hub and
spindle, the sprocket wheel with the inner disk and the outer friction disk.
In the drawings, 1 indicates the drive axle, and 2 the hub section which carries
the drive sprocket. The hub flange 1, has raised clutch teeth 3, havirg at one
end an outer incline 3ª, and at the other, an under-cut incline 3b, as clearly
shown in Figs. 3 and 4.
The drive sprocket wheel 4 is loosely held on the hub 2, and has its inner face
formed with clutch teeth to engage the teeth 3, on the hub, and with such teeth,
form the clutch connection for locking the wheel and hub together on the for-
ward motion of the drive sprocket wheel.
The sprocket wheel 4, has an annular recess 4*, in which projects a rim 5, con-
nected with the hub 12, which serves as a dust guard to keep dirt from entering
between the hub and the sprocket wheel.
6 indicates what I term the fixed disk plate, such term being used to dis-
tinguish it from the disk plate 7, secured to or formed integral with the sprocket
wheel, and the supplemental friction disk 8, detachably secured to but held to
turn with the hub. The plate 6 consists of a central apertured body 6ª, having a
periphery rim 6b, projected laterally at each side to form annular pockets to receive
the disk members 8 and 7, as also interposed packing rings 9-9, of leather or
other suitable material.
In practice the plate 6, is held suspended loosely over the hub spindle and
stationary, so far as relates to the rotary action, it having a projecting lug 6º,
which contacts with the frame fork 10, as clearly shown in Fig. 1. The plate 6

page_text: is suspended from the frame of the machine by means of the spring plate
hanger 11, as indicated in Figs. 1, 2 and 5.
The disk 8, is secured on a reduced left threaded end of the hub spindle so as
to rotate with it without becoming detached.
In operation, to apply the brake, the rider in the act of back-pedalling checks
the forward direction of the sprocket wheel 4, and causes it to have a slight back-
ward motion on the hub. This reverse movement, through the medium of the
inclined clutch teeth causes the sprocket wheel to move laterally against the disk
plate 6. Now, as the pressure is thus applied against the disk 6, at one side,
its opposite sides make frictional contact with disk 8, and thereby exerts a second
frictional resistance on the hub as the said disk 8, is fixedly held from lateral
movement thereon. Thus, it will be seen that the disks 7 and 8, each side of the
disk plate 6, will bear against the said plate 6, and thereby take off any undue
lateral strain thereon as the pressure is equalized from opposite sides.
Furthermore, by providing a double frictional contact means as described a
retarding action is also effected on the spindle hub direct through the medium
of the disk 8, as well as indirect through the engagement of the clutch teeth of
the sprocket and the hub. Again, as a double frictional resistance is effected
against the disk 6, from both sides, it follows that a very small amount of move-
ment of the sprocket wheel will effect a braking action on the hub through the
two distinct retarding means equal to two or three times the lateral movement
of the sprocket against a single rigidly-held friction disk. The action of the
brake device is entirely automatic, and the same is easily controlled by the retard-
ing of back pressure of the rider in checking the forward movement of the wheel.
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 brake mechanism, the combination with the drive axle hub,
having a clutch face, a friction disc detachably secured thereon and rotatable
therewith, a sprocket wheel having a clutch face at one side and a friction face
at the other loosely mounted on the hub, of the non-rotatable disc 6, interposed
between the sprocket wheel friction disc and the hub friction disc and adapted
to be engaged on opposite sides by the said friction disc and sprocket disc when
the movement of the sprocket wheel is retarded, as specified.
2. In a bicycle brake mechanism, the combination with the drive axle and the
hub, said hub having a clutch face and a disc rotatable therewith but held from
lateral movement, of a sprocket wheel having a clutch face and a friction face;
a friction member held between the sprocket wheel and the rotatable friction disc
adapted to be engaged on opposite sides by the said rotatable friction disc and
the sprocket wheel friction face as the movement of such wheel is checked, as
specified.
3. In a bicycle brake of the class described, the combination with the drive
axle, the hub having wedge clutch members and a portion having left threads,
the disc 8 fitted on such threaded portion, the laterally movable sprocket wheel
having wedge clutches at one side and a fixed friction disc 7, at the other side,
the disc 6, having a limited lateral movement on the hub and held between the
discs 7 and 8, said disc 6, having a spring hanger 11, connected with the machine
frame, a stop 6º, to engage a fixed portion of the machine, said disc having
recesses on the opposite side of the disc, all being arranged substantially as shown
and for the purposes described.