An Improved Two-speed Gearing for Velocipedes or other Road Carriages.
Year: 1891

page_text: Date of Application, 8th May, 1891
Complete Specification Left, 16th Jan., 1892-Accepted, 20th Feb., 1892
PROVISIONAL
SPECIFICATION.
An Improved Two-speed Gearing for Velocipedes or other Road
Carriages.
WILLIAM THOMAS SHAW Director and ARTHUR SYDENHAM Manager of the
Crypto Cycle Co. Limited of No. 64 City Road, London E.C. do hereby declare
the nature of this invention to be as follows:-
Our invention has for its object the construction of a gear which shall enable the
rider of a velocipede to alter the ratio of the crank revolutions and the revolutions
of the driving wheel or wheels so as to provide himself with an increase of power
when a hill has to be surmounted or other obstacle from wind or bad road-surface
to be overcome. Our improved gear is constructed so as to form a portion of the
hub of the driving wheel of a bicycle or rear-driving tricycle as follows:
The
The axle of the said wheel is fixed and forms an axis upon which our gear, in
union with the hub of the driving-wheel rotates. Fixed to the axle at one end by
means of a thread, and therefore capable of adjustment, is a disc with a flange
projecting inwards and coned on the inside so as to form one half of a ball-race.
The other half of this ball-race is formed on the opposing recessed face of a disc
made in one piece with a sleeve which turns freely on the fixed axle, and is carried
through to the other end of the said axle. This latter disc is carried out beyond
the coned recess and at its outer periphery is armed with a deep cylindrical flange,
bearing on its outer surface teeth forming a chain-wheel through which by its
connection with a similar chain-wheel on the crank axle, the gear is actuated. On
its inner surface this flange forms a wheel internally toothed which gears with
planet wheels and a central spur-wheel. The internally toothed wheel, the planet
wheels and the central spur-wheel are the three components of an epicyclic train,
as described by us in Patent No. 3230 of 1882. The disc described above, and
which we call the chain wheel disc has a coned ball-race also on its internal surface,
the other half of the cone being formed on a second sleeve, called by us the
central-wheel sleeve which envelops the first sleeve and takes a bearing upon it at
its furthest extremity also, by the medium of a ball-race there formed.
central-wheel sleeve carries the central wheel as one piece with itself, and upon its
external surface at either extremity is formed a ball-race giving support to a third
sleeve which is in fact the hub proper formed with a disc or nave at either end
carrying the spokes of the driving wheel. The nave on the side towards the
chain-wheel carries four studs or pins upon which the planet-wheels before named
rotate. The free ends of these studs are supported by a ring carried by buttresses
coustructed on the face of the nave. This ring is coned on its inner periphery and
so forms the outer half of the ball race which supports the hub-sleeve on this side.
At the other side the half ball-race is coned into a ring screwed into the hub sleeve.
From this description it will be seen that the three components of the epicyclic
train are each formed on a sleeve, that these sleeves take a bearing on each other
and the innermost one upon the fixed axle, through and by means of ball-races in
which run hard steel balls so as to minimize friction. The epicycle train operates
in the manner described in the Letters Patent above-cited: i.e. the power is applied
to the internally toothed wheel, and this acts upon the hub in one of two ways as
follows: If the central-wheel is locked to the hub, then the entire train, with the
chain-wheel and hub, is driven round as one piece. If, on the other hand, the
central wheel of the train is locked to the frame of the machine and is therefore
unable to rotate, the planet wheels are driven round the central-wheel and the hub
disc which carries the studs of the planet-wheels, is driven round at a diminished
speed, depending on the ratio of the internally-toothed wheel to the central wheel.

page_text: This alternative locking of the central wheel to the hub or to the frame is
accomplished at the other end of the axle by a construction which we will now
proceed to describe. The end of the axle, on the opposite side to that on which
the chain-wheel and epicyclic train work, is provided with a shallow cup, with a
deep annular flange closing in the gear on this side. This cup is firmly fixed to
the axle and fork of the machine. Its hollow carries a coned recess forming the
half of a ball-race, the other half of which is formed at the end of the chain-wheel
sleeve. The flange of the cup is armed on its face with a circular row of deep
radial teeth. There is a similar circular row of teeth constructed on the opposing
face of the hub-disc, and between these two rows of teeth is a spur-wheel keyed
loosely on the central wheel sleeve and capable of being moved along it transversely
so as to lock either with the teeth in the fixed cup or with the teeth in the hub
disc, whilst, in the middle position, it just clears both of them. When the spur
wheel is locked to the fixed cup, the central-wheel sleeve is held fast, the epicyclic
train is free to act, the hub is driven with a slower motion than the chain-wheel
and there is a corresponding accession of power. When the spur-wheel is locked
to the hub, the chain wheel, the epicyclic train, and the hub are driven round as
one piece. We employ the following means of traversing the spur-wheel or clutch
so as to obtain these results. The spur-wheel is made so broad as to admit of a
deep circular groove being cut through the centre of the teeth, thus in effect
dividing them into two rows of teeth. The groove is embraced by a ring put on
in two halves and turning easily around the groove. This ring is attached to the
internal face of a broad ring, on the outside of which are four equi-distant threads
of a screw of very coarse pitch formed on the top of four lugs projecting from the
ring. These lugs, carrying their respective threads, pass into four corresponding
slots in the fixed cup, as far as a flange there formed; and the broad ring is thus
held and prevented from revolving. A cylindrical nut with similar threads sunk in
its internal surface, encircles the broad ring and is held in position between the
flange just named and a second flange screwed to the rim of the fixed cup. The
circular nut being moved through the requisite portion of a circle in either direction
traverses the spur-wheel or clutch, as described above.
Dated this 8th day of May 1891
WM. THOS. SHAW.
ARTHUR
SYDENHAM.
COMPLETE SPECIFICATION.
An Improved Two-speed Gearing for Velocipedes or other Road
Carriages.
WILLIAM THOMAS SHAW Director and ARTHUR SYDENHAM Manager of the
Crypto Cycle Co. Limited of No. 64 City Road, London E.C. 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:-
Our invention has for its object the construction of a gear which shall enable
the rider of a velocipede to alter the ratio of the crank revolutions and the
revolutions of the driving wheel or wheels so as to provide himself with an increase
of power when a hill has to be surmounted or other obstacle from wind or bad
road-surface to be overcome.
Our improved gear is constructed so as to form a portion of the hub of the
driving wheel of a bicycle or rear-driving tricycle as follows:-
The axle A of the said wheel is fixed, and forms an axis upon which our gear, in
union with the hub H of the driving-wheel, rotates. Fixed to the axle at one end
by means of a thread, and therefore capable of adjustment, is a disc B with a flange
projecting inwards and coned on the inside so as to form one half of a ball-race.
The other half of this ball-race is formed on the opposing recessed face of a disc C
made in one piece with a sleeve C¹ which turns freely on the fixed axle, and is

page_text: carried through to the other end of the said axle. This latter disc is carried out
beyond the coned recess and at its outer periphery is armed with a deep cylindrical
flange C2, bearing on its outer surface teeth forming a chain-wheel C³ through
which by its connection with a similar chain wheel on the crank axle, the gear is
actuated. On its inner surface this flange forms a wheel internally toothed C*
which gears with planet-wheels D and a central spur-wheel E. The internally
toothed wheel, the planet-wheels, and the central spur-wheel are the three
components of an epicyclic train, as described by us in Patent No. 3230 of 1882.
The disc C described above, and which we call the chain-wheel disc has a coned
ball-race C also on its internal surface, the other half of the cone F being formed
on a second sleeve F called by us the central-wheel sleeve which envelopes the first
sleeve and takes a bearing upon it at its furthest extremity also, by the medium of
a ball-race F2 there formed. The central wheel sleeve carries the central wheel E
as one piece with itself, and upon its external surface at either extremity is formed
a ball-race F3 giving support to a third sleeve H' which is in fact the hub proper
formed with a disc or nave H at either end carrying the spokes of the driving
wheel. The nave on the side towards the chain-wheel carries four studs or pins Di
upon which the planet wheels D before named rotate. The free ends of these studs
are supported by a ring D2 carried by buttresses D³ constructed on the face of the
nave. This ring is coned on its inner periphery D' and so forms the outer half of
the ball-race which supports the hub-sleeve on this side. At the other side the half
ball-race is coned into a ring D' screwed into the hub sleeve. From this description
it will be seen that the three components of the epicyclic train are each formed on
a sleeve, that these sleeves take a bearing on each other and the innermost one
upon the fixed axle, through and by means of ball-races in which run hard steel
balls so as to minimize friction. The epicyclic train operates in the manner
described in the Letters Patent above-cited; i.e. the power is applied to the
internally toothed wheel, and this acts upon the hub in one of two ways as
follows: If the central-wheel is locked to the hub, then the entire train with the
chain-wheel and hub, is driven round as one piece. If on the other hand, the
central-wheel of the train is locked to the frame of the machine, and is therefore
unable to rotate, the planet-wheels are driven round the central-wheel and the hub
disc which carries the studs of the planet-wheels, is driven round at a diminished
speed, depending on the ratio of the internally-toothed wheel to the central wheel.
This alternative locking of the central wheel to the hub or to the frame is
accomplished at the other end of the axle by a construction which we will now
proceed to describe. The end of the axle, on the opposite side to that on which
the chain-wheel and epicyclic train work, is provided with a shallow cup K with a
deep annular flange K closing in the gear on this side. This cup is firmly fixed to
the axle and fork of the machine. Its hollow carries a coned recess K² forming
the half of a ball-race, the other half of which is formed at the end of the
chain-wheel sleeve C¹. The flange of the cup is armed on its face with a circular
row of deep radial teeth K³. There is a similar circular row of teeth constructed
on the opposing face of the hub-disc H2 and between these two rows of teeth is a
spur-wheel L keyed loosely on the central wheel sleeve F and capable of being
moved along it transversely so as to lock either with the teeth in the fixed cup or
with the teeth in the hub disc; whilst in the middle position, it just clears both of
them. When the spur wheel is locked to the fixed-cup, the central-wheel sleeve is
held fast, the epicyclic train is free to act, the hub is driven with a slower motion
than the chain-wheel, and there is a corresponding accession of power. When the
spur-wheel is locked to the hub, the chain wheel, the epicyclic train, and the hub
are driven round as one piece. We employ the following means of traversing the
spur wheel or clutch L so as to obtain these results as shown in detail on sheet II
under the same letters. The spur wheel L is made so broad as to admit of a deep
circular groove L' being cut through the centre of the teeth, thus in effect dividing
them into two rows of teeth. The groove is embraced by a ring M put on in
two halves and turning easily around the groove. This ring is attached to the

page_text: internal face of a broad ring N on the outside of which are four equi-distant
threads N of a screw of very coarse pitch formed on the top of four lugs
projecting from the ring. These lugs, carrying their respective threads, pass into
four corresponding slots N2 in the fixed cup, as far as a flange K' there formed;
and the broad ring is thus held and prevented from revolving. A cylindrical
nut N3 with similar threads sunk in its internal surface, encircles the broad ring
and is held in position between the flange just named and a second flange N
screwed to the deep annular flange K' of the fixed cup K. The circular nut being
inoved through the requisite portion of a circle in either direction traverses the
spur-wheel or clutch as described above.
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
The improved construction of two-speed gearing as and for the purposes herein
described and illustrated by the accompanying drawings.
Dated this 16th day of January 1809
WM. THOS. SHAW.
ARTHUR SYDENHAM.