An Improved Variable Driving Gear for Bicycles and other Velocipedes.
Year: 1896

page_text: Date of Application, 5th Oct., 1896-Accepted, 6th Mar., 1897
COMPLETE SPECIFICATION.
An Improved Variable Driving Gear for Bicycles and other
Velocipedes.
We, EDWARD DAVIES, Architect, and ARTHUR HARRISON, Clerk, both of
21 King William Street, Adelaide, in the Province of South Australia, do
hereby declare the nature of this invention and in what manner the same is to be
performed, to he particularly described and ascertained in and by the following
statement:-
This invention relates to the construction of an improved variable driving gear
for bicycles and other velocipedes.
3
The object of our invention is to provide a driving gear for bicycles and other
velocipedes which shall be capable of being adjusted at will so that it can be,
geared lower or higher to increase the power or the speed according as the
circumstances of the road or track may require. By means of our invention great
power can be obtained for hill climbing and the gear can be readily and quickly.
readjusted without the use of a tool for increase of speed so soon as the ascent
or other difficulty of the road shall have been passed.
We accomplish this by discarding the ordinary chain and sprocket wheel and
use in place thereof, a gearing of special design, the mechanism of which is
hereinafter described and shown in the accompanying drawings.
Fig. 1. is a side elevation partly in section of a portion of the frame and hind.
wheel of a bicycle with our improved variable gearing.
Fig. 2. a plan of the same partly in section showing also the treadle attachment.
Fig. 3. full face view of studded disc with locking clips.
Fig. 4. side elevation of the same.
In our invention a disc wheel A attached to the pedal shaft has its inner face
bevelled parallel with the line of the driving shaft. Such inner face has three or
more concentric circles or rings of indentations A¹ preferably cone shaped. The
indentations A' are arranged at regular and equidistant intervals in the circles or
rings as shown more particularly in Fig. 1. The disc wheel A has a central
squared aperture so as to slide upon the squared end of the pedal shaft B. It is
held in position thereon by a pair of locking clips C engaging channels or slots
cut for the purpose in opposite sides of the shaft. These locking clips Care
maintained in position by springs C₁ as shown in the accompanying drawings.
The outer face of the disc wheel A is recessed or sunk in order to receive the
locking clips and so that the latter may not project beyond its outer face. In
order to communicate the motion from the disc wheel A to the driving wheel we
provide a driving shaft D both ends of which revolve in suitable ball bearings in
the frame of the machine. A portion of the front end D' of the driving shaft D is
made square and is provided with a disc E having upon its periphery cone slaped
studs or projections E' fitting and engaging the indentations upon the disc wheel A.
The disc E is also provided with lucking clips C and springs C of similar con-
struction to those of the disc wheel A. The squared end D of the driving
shaft D is channelled or slotted at intervals in order to receive the locking clips C
and to retain the disc E in positions corresponding with the respective concentric
rings of indentations A¹ upon the inner face of the disc wheel A. The boss or hub
of the driving wheel of the machine is provided with a disc F the outer face of
which has a single ring or circle of indentations similar to the indentations A¹ and
to the rear end of the driving shaft D is fixed a disc G the periphery of which has
a series of studs G¹ similar to the studs E¹ and engaging indentations in the
disc F.

page_text: In the accompanying drawings three concentric rings or circles of indentations A'
are shown on disc A but we do not bind ourselves to any particular number. By
means of these concentric rings or circles of indentations the power or the speed
can be increased at will; the smaller the circle or ring of indentations engaged the
greater the power and vice versa.
When an alteration of gear is desired the springs C¹ are depressed and the
locking clips C of the disc wheel A are withdrawn from the channels or slots B¹
the disc wheel A is then moved forward so as to release the studs E' from the
indentations A'. The springs C of the disc E are then depressed the locking
clips C are withdrawn from their slots and disc E moved along the squared end Di
of the driving shaft D until the desired position is reached when the locking
clips C are placed in the slots determining the new position. The disc wheel A is
then slid back into its former position and the locking clips replaced when the
studs E engage a fresh concentric ring or circle of indentations A' and the
gearing is complete.
We wish it to be understood that we do not confine ourselves to the exact forin
of the studs E' and their corresponding indentations A' shown on the drawings.
We find however that this shape answers our purpose. The studs and indentations
may if so desired be made more or less pointed without interfering with the principle
of our invention.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is-
1. The herein described variable driving gear for bicycles or other similar
velocipedes consisting of a disc wheel (such as A), baving indentations (such
as A¹), a disc (such as E) having studs (such as E¹) driving shaft (such as D),
a disc (such as G) fixed to D and having studs (such as G) a disc (such as F)
fixed to driving wheel having indentations (such as F¹) substantially as herein
described and for the purpose indicated.
2. In variable driving gear of bicycles and other similar velocipedes a disc wheel
(such as A) having its inner face bevelled parallel to the driving shaft (such as D)
substantially as herein described and for the purpose indicated.
3. In variable driving gear of bicycles and other similar velocipedes a disc wheel
(such as A) having a square aperture and provided with locking clips (such as C)
preferably held in position by springs (such as C¹) in combination with a pedal
spindle (such as B) having a squared end (such as D¹) and provided with channels
or slots (such as B¹) substantially as herein described and for the purpose
indicated.
4. In the variable driving gear of bicycles and other similar velocipedes the
combination with a disc wheel (such as A) having a series of concentric rings or
circles of indentations (such as A') and preferably so arranged as to slide upon the
pedal spindle (such as B) of a disc (such as E) the periphery of which is provided
with a series of studs (such as E) fitting and engaging the indentations (such
as A¹) the disc (such as E) being so arranged as to slide upon the squared end of
the driving shaft (such as D) substantially as herein described and for the purpose
indicated.
5. Iu variable driving gear of bicycles and other velocipedes the combination
with a disc (such as E) of locking clips (such as C) preferably held in position by
springs (such as C¹) and so arranged as to engage channels or slots cut for the
purpose in the end of the driving shaft substantially as herein described and fo
the purpose indicated.
TL: FAL
SO 100
BOULT & WADE,
Agents for the Applicants.