Improvements in Driving Gears for Bicycles,
Year: 1898

page_text: Date of Application, 26th Aug., 1898--Accepted, 26th Aug.,
1899
COMPLETE SPECIFICATION.
Improvements in Driving Gears for Bicycles,
I, HENRY THOMAS BRAGG, Manufacturer, of 263, Broadway, New York City, in
the County and State of New York, United States of America, do hereby declare
the nature of this invention and in what manner it is to be performed to be
particularly described and ascertained in and by the following statement;
-
This invention relates to that class of driving gears for bicycles known as
"chainless gears."
"
The invention has for its objects, to reduce the cost of chainless gears, to reduce
or deaden the noise incident to the operation of such gears, to so construct the
engaging parts of the gears as to render them in a great measure self-lubricat-
ing; to so construct the engaging parts that those most subject to wear may be
readily removed and replaced with but slight cost in time or money, and without
the aid of a skilled repairer.
With these objects in view the invention consists in details of construction, and
combination which will be hereafter described and claimed.
In the accompanying drawings, Figure 1 is a side elevation of so much of a
bicycle frame as to illustrate my invention, some of the parts being in section.
Figure 2 is a top plan view thereof partly in section.
Figure 3 is a detail of the lautern gear.
In carrying my invention into practical effect, I provide the crank shaft, and
rear hub with fixed driving and driven gears of appropriate size, and connect
said gears by means of a shaft located within one of the rear fork-sides, said
shaft being fitted at its ends with fixed gears meshing with the gears attached to
the crank shaft and rear hub.
Referring to the drawings, 1 designates a shaft, fitted near its forward end with
a lantern gear 2 composed of end disks 3 and 4, and spindles 5, fitted at their
ends in perforations of said end disks adjacent to the edges thereof. In the
instance shown, the ends of the spindles are tightly riveted into the fixed inner
disk 3, and at their opposite ends are dressed to snugly fit the perforations of
the outer disk 4, the latter being slipped over said spindle ends and shaft, and
locked by means of a nut 0, threaded on the shaft 1. Provision is made to
prevent the rotation of the outer disk 4, upon the shaft 1, in order that pressure
on the spindles, during operation, will not tend to shift said disk.
A gear 2, similar in all respects to that above described, is secured at the rear
end of shaft 1.
By providing for the re-placement of the outer disk 4, of the gear I am enabled
to remove spindles 5, that become worn or bent, in use. In carrying forward this
feature of my invention, however, I prefer to connect the spindles with the inner
disk 3, detachably, as for instance by means of screw threads, in order that one
or more of the spindles may be the more readily detached if worn or bent, without
disturbing the others, and I also contemplate seating said spindles so loosely in
the plates 3 and 4, that they may rotate therein on contact with a meshing gear,
thus presenting new surface to wear.
As a separate improvement, in this connection, I provide each spindle 5 of these
lantern gears with a sleeve or tubular bushing 7 designed to take the wear of

page_text: the meshing gear, and while these sleeves may be formed of various materials,
metallic or fibrous, for the purpose above stated, I prefer to employ sleeves of a
fibrous material, which will serve to deaden the sound or noise incident to the
operation of meshing gears, and also employ, for such sleeves a substance or
material which will absorb oil, thus providing for the lubrication of the gears. I
have employed, for this purpose, sleeves of raw hide snugly fitted on the
spindles 5, and of such length that they will not be held against turning on the
spindles by the endwise pressure of the plates 3 and 4.
The shaft 1 is journaled at its ends in suitable bearings 8 and 9 secured to or
forming part of the frame, the bearing 8 being fixed to the crank hanger at such
point that the gear 2 at the forward end of the shaft 1 will engage a driving
gear 10 keyed to the crank shaft 11, and the bearing 9 being secured at the rear
end of the rear frame of the bicycle in such position that the gear 2, of shaft 1
will engage a driven gear 12, secured on the rear hub of said bicycle.
The gears 10 and 12, here shown each comprise a flat disk 13, from the face
of which, near the periphery, project teeth or studs 14, thus forming a crown
wheel. These gears may be made quite light, and at small cost, since the parts
subject to wear, namely, the teeth or studs 14, may be turned up from tool steel,
said studs being then tightly seated in perforations formed in disk 13 of cheaper
metal at suitable points, and securely riveted therein.
The shaft 1 is preferably housed within one of the rear fork-sides of the bicycle
frame, as is usual, and any suitable housings A, B are provided to enclose the
two pairs of gears.
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 bicycle driving gear, the combination with driving and driven gears,
and a shaft journaled in bearings carried by the bicycle frame, of lantern gears
secured to said shaft consisting of a fixed end disk, a removable end disk, and
spindles supported in said disks, the wearing surfaces of which are removable,
substantially as described.
2. In a bicycle driving gear, the combination with driving and driven gears,
and a shaft journaled in bearings carried by the bicycle frame, of lantern gears
secured to said shaft consisting of a fixed disk and spindles supported therein, a
removable disk having perforations for the reception of the spindles at one end,
and means to lock the removable disk on the shaft, substantially as described.
3. In a bicycle driving gear, the combination with driving and driven gears,
and a shaft journaled in bearings carried by the bicycle frame, of lantern gears
secured to said shaft consisting of a fixed end disk, a removable end disk and
removable spindles supported in said disks, substantially as described.
4. In a bicycle driving gear, the combination with driving and driven gears,
and a shaft journaled in bearings supported by the bicycle frame, of lantern
gears secured to said shaft, consisting of a fixed disk, a removable disk, and
spindlos supported in said disks, the wearing surfaces of which are removable,
substantially as described.
5. In a bicycle driving gear, the combination with driving and driven gears,
and a shaft journaled in bearings carried by the bicycle frame, of lantern gears
consisting of fixed and removable disks, spindles supported in said disks, and
fibrous lubricating bushings removably mounted on said spindles, substantially
as described.
Dated this 26th day of August 1898.
WHEATLEY & MACKENZIE,
40, Chancery Lane, London, W.C., Agents.