Improvements in and relating to Variable Driving Gear for Bicycles and other Velocipedes.
Year: 1894

page_text: Date of Application, 20th Aug., 1894
Complete Specification Left, 17th June, 1895-Accepted, 20th July, 1895
PROVISIONAL SPECIFICATION.
Improvements in and relating to Variable Driving Gear for Bicycles
and other Velocipedes.
I, CHARLES ARTHUR ALLISON, of 52 Chancery Lane, London, in the County
of Middlesex, Patent Agent, do hereby declare the nature of this invention
(which has been communicated to me from abroad by Arthur Macdonald Martin,
of Manning Road, East Malvern, in the Colouy of Victoria, Surveyor), to be as
follows:-
This invention of improvements in and relating to variable driving gear for
bicycles and other velocipedes has been devised for the purpose of enabling
cyclists to vary the gearing of their machines from a high to a low speed whilst
travelling. At the same time it dispenses with the necessity for a brake owing to
the facility with which the machine can be geared down and then stopped by
"back-pedalling."
According to this invention I mount two loose or idle pulleys of different sizes
upon the crank spindle-preferably on opposite sides of its bearings and connect
said pulleys by a chain or other gearing with different sized pinions upon the hub
or other convenient part of the main drive wheel, the larger pulley gearing on to
a smaller pinion, and vice versa, the smaller one gearing on to a larger one whereby
the machine will be geared up or down according to the set of gear used.
The loose or idle driving pulleys on the crank spindle can be thrown into or out
of gear therewith by shifting a pair of clutches along said spindle to one side or
the other, according to the gearing required to be used, said clutches working along
a feather upon said spindle. The two clutches are connected together and moved
simultaneously by a pivotted lever trained by suitable connections to the handle
bar of the machine instead of or in addition to the ordinary brake lever, it being
easily understood that with my invention the brake may if desired be dispensed
with, owing to the facility with which the machine can be geared down as well for
stopping as for hill climbing purposes.
With this invention the advantages of both a high and a low geared machine
are combined in the one machine, thus enabling cyclists to travel with greater ease
and comfort than is possible with the ordinary single geared machines.
Dated this 20th day of August 1894.
ALLISON BROS.,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in and relating to Variable Driving Gear for Bicycles
and other Velocipedes.
I, CHARLES ARTHUR ALLISON, of 52 Chancery Lane, London, in the County
of Middlesex, Patent Agent, do hereby declare the nature of this invention (which
has been communicated to me from abroad by Arthur Macdonald Martin, of
Manning Road, East Malvern, in the Colony of Victoria, Surveyor), and in what
827

page_text: manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :-
This invention of improvements in and relating to variable driving gear for
bicycles and other velocipedes has been. devised for the purpose of enabling
cyclists to vary the gearing of their machines from a high to a low speed whilst
travelling. At the same time it dispenses with the necessity for a brake owing
to the facility with which the machine can be geared down and then stopped by
"back-pedalling."
**
According to this invention, I mount two loose or idle pulleys of different sizes
upon the crank spindle preferably on opposite sides of its bearings and connect
said pulleys by chain or other gearing with different sized pinions upon the hub or
other convenient part of the main drive wheel the larger pulley gearing on to a
smaller pinion and vice versa the smaller pulley gearing on to a larger pinion
whereby the machine will be geared up or down according to the set of gear used.
The loose or idle driving pulleys on the crank spindle can be thrown into or out
of gear therewith by shifting said spindle to one side or the other according to
the gearing required to be used, so as to cause a pin upon one or other of the
cranks to engage with one of said wheels. The spindle and cranks are moved by
a pivotted lever trained by suitable connections to any convenient part of the
machine.
Referring to the accompanying drawings,―
Figure 1, is a side elevation of part of a rear driving safety bicycle fitted with
my invention, and
Figure 2, is a plan thereof whilst,
Figure 3, is a vertical section on line 3-3, Figure 1, but drawn to a much larger
scale, and
Figure 4, is a vertical transverse section on line 4-4 Figure 3.
The same letters of reference indicate the same parts in all the figures.
A A² represent the two loose or idle pulleys of different sizes which are mounted
upon the crank spindle B one on each side of the ball bearings C in which said
spindle is mounted whilst D D' represent the cranks upon the ends of said spindle
and EE represent inwardly projecting pins upon said cranks which serve to
project into and engage with holes F or recesses provided for the purpose in the
pulleys A A
G, G¹ represent the sprocket pinions which are provided upon the main drive
wheel spindle one on either side of said wheel whilst H H' represent the drive
chains used for communicating motion from the pulleys A A' to said pinions G G¹
in such a way that the larger pulley A drives the smaller pinion G and vice versa,
the smaller pulley A¹ drives the larger pinion G'.
I represents the pivotted lever to whose ends are attached rods J leading to a
small hand lever K mounted upon any convenient part of the machine as for
instance upon the main frame just in front of the saddle as shown in Figure 1.
A small catch piece L in front of the hand lever K serves to retain said lever on
whichever side it may be moved by the rider and therefore with either the high
or the low speed gear in operation as required.
The lever has a short projecting arm M which engages in circumferential
teeth or grooves N upon a ring O encircling the spindle B, balls P being provided
between said ring and a fixed collar Q upon said spindle in order to minimise
friction, whilst at the same time ensuring a positive motion being transmitted to
the spindle in either direction when required. The loose or idle pulleys A A'
are prevented from moving laterally by being provided with sleeves R which form
the inner sides of the ball bearings shown whilst the spindle B passes freely
through said sleeves.
With this invention the advantages of both a high and a low gear are combined
in the one machine thus enabling cyclists to travel more quickly and with greater
ease and comfort than is possible, with the ordinary single geared machines, owing
to the choice of the two speeds, which can be employed according to requirements:

page_text: For instance, in ascending a steep hill the low gear can be used whilst on the flat
if the roads are good the high gear may be utilised.
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,
First. In variable driving gear for bicycles and other velocipedes two loose or
idle pulleys of different sizes upon the crank spindle so arranged that either of
them can be thrown into gear with said spindle substantially as and for the
purposes herein described and explained and as illustrated in the accompanying
drawings.
Second. In variable driving gear for bicycles and other velocipedes the com-
bination with two loose or idle pulleys of a crank spindle adapted to be moved
end wise through said pulleys substantially as and for the purposes herein specified
and as illustrated in the accompanying drawings.
Dated this 17th day of June One thousand eight hundred and ninety-five.
ALLISON BROS.,
Agents for the Applicant.