Improvements in Gearing suitable for Cycles.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in Gearing suitable for Cycles.
I, SAMUEL HENRY CROCKER, Engineer, of 31, Furnival Street, Holborn, do
hereby declare the nature of this invention to. be as follows:-
This invention relates to a new mechanical motion, and consists of a differential
crank driving gear especially suitable for application to cycles, but will be found
useful for transmitting power in other machines.
I will however describe the gearing when applied to a bicycle. Upon the
hub of the back or driving wheel of the bicycle I mount a toothed wheel. This
wheel engages with a specially designed rack which forms the termination of
an ordinary connecting rod engaging with the pedal crank so that when the
pedals are revolved, the crank is also revolved and the connecting rod terminating
with the rack moves backwards and forwards in the usual manner.
The specially designed rack before referred to consists of two parallel metal
pieces kept apart from each other a slightly greater distance than the thickness
of the wheel by means of circular rivets or pins placed at regular intervals across
from one side to the other and these pins act as teeth to engage with recesses
formed upon the wheel.
One of the outside metal pieces before referred to in the rack is grooved to
a required distance and this groove terminates at each end preferably in a semi-
circle.
Upon the axle carrying the wheel I mount a crank free to revolve upon the
said axle and provided at its end with a projecting circular pin taking into the
grooved recess before mentioned. The crank and groove act to keep the rack
from becoming disengaged at any time with the wheel.
In order to lessen friction I propose to put rollers on to the connecting pins
in the rack, and also upon the projecting pin upon which the grooved recess
travels. The action of the rack upon the wheel is alternately in the nature of a
crank and of a rack.
The rivets or pins and rollers in the rack acting as teeth are regularly spaced
to register with corresponding recesses upon the wheel. The device can be
geared up to any extent in accordance with the throw of the crank connected to
the pedal axle and the length of the rack which is now provided with as many
pins acting, as teeth, as will obtain the desired gear proportionately with the
number of recesses upon the wheel to receive the said teeth.
In order that the invention may be more clearly understood, reference is had
to the accompanying sheet of drawings in which Fig. 1 is a front elevation of
my improved gearing device; Fig. 2 is a section through the same; Fig. 3 is a
plan of my improved mechanism, and Fig. 4 is a back elevation of the wheel
and rack showing the crank and recess in rack which keeps the rack at all
times from parting company with the wheel.
The parts are marked with like letters of reference
thhout
as far
as possible

page_text: In Fig. 1, A is the wheel with recesses Barranged to receive the pins or teeth C
of the rack. These pins are shown in dotted lines. D is the rack termination
of the connecting rod E.
In Fig. 2, F is the crank loosely mounted upon the axle of the wheel, carrying
the projecting pin f upon which the recess travels to and fro.
In Figs. 3 and 4, the parts before referred to are marked with like letters of
reference.
The rack being pulled forward and pushed backward by the connecting rod
travels all around the wheel, thus transmitting the motion from the pedal axle
to the axle of the driving wheel of the bicycle.
When applying my invention to a bicycle I prefer to place a similar driving
gear upon each side of the driving wheel when the racks are placed in such
relationship to each other as to avoid the possibility of any dead centre.
P
100%
GEO. H. RAYNER,
37, Chancery Lane, London, Agent for the Applicant.
I, SAMUEL HENRY CROCKER, Engineer, of 31, Furnival Street, Holborn, 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 a new mechanical motion, and consists of a differential
crank driving gear especially suitable for application to cycles, but will be found
useful for transmitting power in other machines.
I will however describe the gearing when applied to a bicycle. Upon the
hub of the back or driving wheel of the bicycle I mount a toothed wheel. This
wheel engages with a specially designed rack which forms the termination of
an ordinary connecting rod engaging with the pedal crank so that when the
pedals are revolved, the crank is also revolved and the connecting rod terminating
with the rack moves backwards and forwards in the usual manner.
The specially designed rack before referred to consists of two parallel metal
pieces kept apart from each other a slightly greater distance than the thickness
of the wheel by means of circular rivets or pins placed at regular intervals across
from one side to the other and these pins act as teeth to engage with recesses
formed upon the wheel.
One of the outside metal pieces before referred to in the rack is grooved to
a required distance and this groove terminates at each end preferably in a semi-
circle.
Upon the axle carrying the wheel I mount according to one arrangement a
crank free to revolve upon the said axle and provided at its end with a projecting
circular pin taking into the grooved recess before mentioned. The crank and
groove act to keep the rack from becoming disengaged at any time with the
wheel.
In order to lessen friction I propose to put rollers on to the connecting pins
in the rack, and also upon the projecting pin upon which the grooved rack
travels. The action of the rack upon the wheel is alternately in the nature of a
crank and of a rack.
The rivets or pins and rollers in the rack acting as teeth are regularly spaced
to register with corresponding recesses upon the wheel. The device can be

page_text: geared up to any extent in accordance with the throw of the crank connected to
the pedal axle and the length of the rack which is now provided with as many
pins acting as teeth, as will obtain the desired gear proportionately with the
number of recesses upon the wheel to receive the said teeth.
In order that the invention may be more clearly understood, reference is had
to the drawings filed with my Provisional Specification in which Fig. 1 is a
front elevation of my improved gearing device, Fig. 2 is a section through the
same Fig. 3 is a plan of my improved mechanism, and Fig. 4 is a back elevation
of the wheel and rack showing the crank and recess in rack which keeps the
rack at all times from parting company with the wheel.
The parts are marked with like letters of reference
throughout.
as far as possible
In Fig. 1A is the wheel with recesses Barranged to receive the pins or teeth C
of the rack. These pins are shown in dotted lines. D is the rack termination
of the connecting rod E.
In Fig. 2, F is the crank loosely mounted upon the axle of the wheel, carrying
the projecting pin f' upon which the recess travels to and fro.
In Figs. 3 and 4, the parts before referred to are marked with like letters of
reference.
The rack being pulled forward and pushed backward by the connecting rod
travels all around the wheel, thus transmitting the motion from the pedal axle
to the axle of the driving wheel of the bicycle.
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. An improved gearing for cycles and the like, comprising a wheel having
recesses formed on its periphery, a rack formed on a connecting rod and adapted
to engage with the recessed wheel and means for retaining the said rack in
engagement with the wheel, substantially as described and for the purposes
specified.
2. An improved gearing for cycles and the like comprising a wheel A having
recesses B formed on its periphery, a rack D, the pins or teeth C of which are
adapted to engage with the recesses B of the wheel A, the said rack D being
formed on the connecting rod E, and the crank F loosely mounted on the axle
so that the projecting pin f¹ engages with the recess for retaining the rack D
in engagement with the wheel A, substantially as described with reference to the
drawings and for the purposes specified.
+000
GEO. H. RAYNER,
37, Chancery Lane, London, Agent for the Applicant.