IMPROVEMENTS IN VELOCIPEDES AND APPARATUS CONNECTED THEREWITH
Year: 1883

page_text: LETTERS PATENT to William Thomas Shaw of Adelaide Road Surbiton in
the County of Surrey and William Sydenham of Wood Street Chambers Old
Street in the City of London for an Invention of "IMPROVEMENTS IN
PROVISIONAL SPECIFICATION left by the said William Thomas Shaw
and William Sydenham at the Office of the Commissioners of Patents on the
26th January 1883.
WILLIAM THOMAS SHAW of Adelaide Road Surbiton in the County of Surrey
and WILLIAM SYDENHAM of Wood Street Chambers Old Street in the City
of London "IMPROVEMENTS IN VELOCIPEDES AND APPARATUS CONNECTED
THEREWITH
"
In tricycles and other velocipedes known as double drivers in which there are
two driving wheels various arrangements have been adopted by virtue of which
one wheel is enabled to travel faster than the other whenever the machine deviates
from a straight course-This is effected by various contrivances known as
differential gearing all of which depend for their action upon the fact that the
wheels instead of revolving in attachment to one and the same axis revolve upon
two axes (equal or unequal) placed in the same line and joined together by
interposed gearing The gearing is necessarily so contrived that supposing the
machine to be suspended the rotation of one of the wheels in one direction acts
through the gearing and rotates the other wheel in the opposite direction. A
similar effect is produced when the machine is driven along the ground in a curved
direction The acceleration of the outer wheel produces a corresponding retardation
of the inner wheel and the machine is enabled to describe the required curve in
the most perfect manner.
According to our invention we construct the gearing in the following manner.
Where the two axes meet together each axis has fixed upon it a toothed wheel―
Each axis is surrounded by a tubular sleeve which at its inner end has a flange
surrounding it this flange is made to come into close proximity to the toothed
[Price Gd1

page_text: wheel on the end of the axis-The two flanges are made of larger diameter than
the two toothed wheels in order that distance pieces may be placed between them
and the two flanges be held together by screw bolts so as to lock the two sleeves
securely together-The distance piece may be a cylinder concentric with the axes
and projecting from the outer circumference of one flange so that it may not only
form a distance piece but also enclose the space between the two flanges-The two
toothed wheels are made of equal diameter and they are geared together by two
or more pairs of toothed pinions preferably by two pairs of pinions-One pinion
of each pair is made to gear with one toothed wheel and the other pinion with
the other toothed wheel the two pinions being also made to gear the one with the
other in a central space left between the two toothed wheels-the axes of the
toothed pinions turn in holes or bearings formed to receive them in the two
flanges.
By this construction the use of studs held at one end only for carrying the
pinions is avoided and other important advantages are secured-The sleeve is driven
in the ordinary way by means of a pulley fixed thereto
Although differential driving gear such as above described is very essential and
efficient when the machine is describing a curve it leads to incessant side strain on
the steering wheel and consequent loss of power whenever the machine is running
in a straight line-This arises from the fact that the road resistance encountered
by the two driving wheels is rarely if ever (except on a track) exactly equal.
Whatever tends to retard one wheel puts the other forward to a corresponding
degree and vice versa and to this extent there is a constant tendency in the driving
wheels to place themselves out of parallelism with the forward direction of the
steering wheel,
To remedy this defect we employ automatic apparatus to control 'the differential
gear and prevent it from acting except when the machine is running on a curve.
One method of effecting this may be described as under.
Suppose the driving wheels to be fixed to two equal axes running within a sleeve
enlarged in the middle to receive the differential gear, the power being imparted
through the sleeve by means of a pulley fixed thereto in the ordinary way. The
sleeve on the further side from the pulley instead of being carried along the axis
up to the side frame is terminated a few inches from the latter by a collar with a
broad flange on the side next to the exposed axle.
The axle at the part coincident with the flange has firmly fastened to it a broad
and strong disc the round circumference of which is parallel with the inside of the
flange and separated from it by an annular space containing the parts described
below.
The back of this annular space forming the inside of the collar is armed with
three equidistant curved levers pivotted on the inside face of the collar close to the
axle disc so so that the levers may near their pivots be made to press forcibly on
the latter and grip and hold it fast whenever the ends of the levers are pressed
inwards towards the axle. This is accomplished by means of a ring with wedge
shaped depressions cut in its interior surface for the ends of the three levers to
project into. This ring which is held within the flange of the collar can be rotated
through so much of a circle as will enable the lever ends to travel the length of
the depressions above referred to. When the ends of the levers are at the deepest
parts of the depressions they exert no pressure on the axle disc while when the
ring is shifted round so as to bring the shallow portion of the depressions into play
the disc is tightly grasped by the levers and the axle and sleeve are firmly fastened
together. In another arrangement we attach the flanged collar to the axle and the
disc to the sleeve in which case the levers are made to exert their pressure outwards.
The movement of the ring is effected from behind by means of a sliding grooved
ring actuated by a bell crank and arm connected with the steering handle in such
a way that when the steering wheel is set straight. The ring is pushed round the
lever ends are pressed inwards (or outwards as the case may be) and the axle and
sleeve revolve as one by which means the play of the differential gearing consequent

page_text: on unequal road resistance is stopped and all three wheels maintain a parallel
course. On the other hand so soon as the steering handle is turned the levers are
released and the differential gearing comes into action and enables the machine to
move in a curved direction. The arm connecting the steering handle and the
grooved ring is actuated by means of a cam eccentric fixed on the axle of the
steering handle.
By means of a spring and catch the cam is locked when the handle is placed for
straight running so that the rider is at liberty to release is hand from the steering
handle until he wishes to alter the course of the machine.
In place of the usual flat band brake we make use of a brake pulley the surface
of which is angular in section. To the inside of the band we fix a thick piece of
leather capable of taking the shape of the angular groove and by this means we
are enabled to obtain very great power there being a compression exerted between
three surfaces instead of a simple sliding pressure between two surfaces.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Thomas Shaw and William Sydenham in the Great Seal
Patent Office on the 26th July 1883.
WILLIAM THOMAS SHAW of Adelaide Road Surbiton in the County of Surrey
and WILLIAM SYDENHAM of Wood Street Chambers Old Street in the City
of London "IMPROVEMENTS IN VELOCIPEDES AND APPARATUS CONNECTED
THEREWITH
"
In tricycles and other velocipedes known as double drivers in which there are
two driving wheels various arrangements have been adopted by virtue of which
one wheel is enabled to travel faster than the other whenever the machine deviates
from a straight course. This is effected by various contrivances known as
differential gearing all of which depend for their action upon the fact that the
wheels instead of revolving in attachment to one and the same axis revolve upon
two axes (equal or unequal) placed in the same line and joined together by
interposed gearing. Such gearing is necessarily so contrived that supposing the
machine to be suspended and the pedal shaft held stationary the rotation of one of
the wheels in one direction acts through the gearing and rotates the other wheel
in the opposite direction. A similar effect is produced when the machine is driven
along the ground in a curved direction. The acceleration of the outer wheel is
accompanied by a corresponding retardation of the inner wheel and the machine is
enabled to describe the required curve in the most perfect manner.
According to our Invention we construct the gearing in the following manner.
Where the two axes meet together each axis has fixed upon it a toothed wheel.
Each axis is surrounded by a tubular sleeve which at its inner end has a flange
surrounding it-this flange is made to come into close proximity to the toothed
wheel on the end of the axis. The two flanges are made of larger diameter than
the two toothed wheels in order that distance pieces may be placed between
them and the two flanges be held together by screw bolts so as to lock the two sleeves
securely together and give support to the axis. The distance piece may be a
cylinder concentric with the axes and projecting from the outer circumference of
one flange so that may not only form a distance piece but also enclose the space
between the two flanges. The two toothed wheels are made of equal diameter and
they are geared together by two or more pairs of toothed pinions preferably by two
pairs of pinions. One pinion of each pair is made to gear with one toothed wheel
and the other pinion with the other toothed wheel the two pinions being also
made to gear the one with the other in a central space left between the two toothed
wheels the axes of the toothed pinions turn in holes or bearings formed to receive
them in the two flanges.
By this construction the use of studs held at one end only for carrying the
pinions is avoided and other important advantages are secured. The sleeve is
driven in the ordinary way by means of a pulley fixed thereto. One of the axles
may be tubular and the other axle prolonged through it so as to form a continuous
axle from one side of the machine to the other.
Although differential driving gear such as above described is very essential and
efficient when the machine is describing a curve it leads to incessant side strain
on the steering wheel and consequent loss of power whenever the machine is
running in a straight line. This arises from the fact that the road resistance
encountered by the two driving wheels is rarely if ever (except on a track) exactly
equal. Whatever tends to retard one wheel puts the other forward to a
corresponding degree, and vice versa and to this extent there is a constant tendency

page_text: in the driving wheels to place themselves out of parallelism with the forward
direction of the steering wheel.
To remedy this defect we employ automatic apparatus to control the differential
gear and prevent it from acting except when the machine is running on a curve.
One method of effecting this may be described as under.
Suppose the driving wheels to be fixed to two equal axes running within a
sleeve enlarged in the middle to receive the differential gear the power being
imparted through the sleeve by means of a pulley fixed thereto in the ordinary
way. The sleeve on the further side from the pulley instead of being carried along
the axis up to the side frame is terminated a few inches from the latter by a collar
with a broad flange on the side next to the exposed axle.
The axle at the part coincident with the flange has firmly fastened to it a broad
and strong disc the circumference of which is separated from the inside of the
flange by an annular space containing the parts described below.
The back of this annular space, forming the inside of the collar, is armed with
three equidistant curved levers pivoted on the inside face of the collar close to the
axle disc so that the levers may near their pivots be made to press forcibly on the
axle disc and grip and hold it fast whenever the ends of the levers are pressed
inwards towards the axle. This is accomplished by means of a ring with wedge
shaped depressions cut in its interior surface for the ends of the three levers to
project into. This ring which is held within the flange of the collar can be rotated
through so much of a circle as will enable the lever ends to travel the length of
the depressions above referred to. When the ends of the levers are at the deepest
parts of the depressions they exert no pressure on the axle disc while when the
ring is shifted round so as to bring the shallow portion of the depressions into
play the disc is tightly grasped by the levers and the axle and sleeve are firmly
fastened together. In another arrangement we attach the flanged collar to the
axle and the disc to the sleeve in which case the levers are made to exert their
pressure outwards. The movement of the ring is effected from behind by means
of a sliding grooved ring actuated by a bell crank and arm connected with the
steering handle in such a way that when the steering wheel is set straight, the ring
is pushed round, the lever ends are pressed inwards (or outwards as the case may
be) and the axle and sleeve revolve as one, by which means the play of the
differential gearing consequent on unequal road resistance is stopped and all three
wheels maintain a parallel course. On the other hand so soon as the steering
handle is turned, the levers are released and the differential gearing then comes
into action and enables the machine to move in a curved direction. The arm
connecting the steering handle and the grooved ring is actuated by means of a
cam or eccentric fixed on the axle of the steering handle.
By means of a spring and catch the cam is locked when the handle is placed for
straight running so that the rider is at liberty to release his hand from the steering
handle until he wishes to alter the course of the machine.
In order that our Invention may be fully understood we will proceed to describe
the drawings hereunto annexed.
DESCRIPTION OF THE DRAWINGS
Figure 1 shews a plan view and Figure 2 a side elevation of differential gear
constructed according to our Invention. Figure 3 is a section taken on the
line A. A. Figure 2. A B are two axes in a line with one another-CC are tubular
sleeves within which the axes can revolve-D D are disc flanges on the inner ends
of the sleeves-D' is a cylinder projecting from the circumference of one of these
discs D³ are screws by which the other disc is secured to lugs projecting inwards
from the end of the cylinder-the two sleeves are thus formed into one continuous
sleeve. The sleeve has fixed upon it a wheel not shewn in the drawing and by
this wheel it can be driven in the ordinary way-E E are two toothed wheels of
equal diameter one is fixed on the inner end of the axis A the other on the inner

page_text: end of the axis B a space being left between the wheels as shewn-F F are two
pairs of pinions their axes are received into holes formed to receive them in the
discs D as is best seen in Figure 3. One pinion of each pair gears with the toothed
wheel E on the axis A and the other with the toothed wheel E on the axis B and
the two pinions gear with one another in the space between these two wheels as is
also seen in Figure 3.
We would state that we are aware that it is not new to construct differential
driving gear with a pair or pair of pinions gearing with one another and also with
one pinion of each pair gearing with a toothed wheel on the axle of one driving
wheel and the other with a toothed wheel connected with the other driving wheel
but in all such previous constructions the pinions have necessarily been carried on
studs held at one end only whereas by our construction the pinions are enclosed
within a tubular chamber forming an enlargement of the sleeve within which the
axles can turn and the pinions are supported from both ends of this tubular
chamber whereby a far stronger construction is obtained and the pinions are
always kept accurately in position so that the gearing of these pinions the one
with the other and also with the toothed wheels on the axles is ensured. Figure 4
shews a longitudinal section of differential driving gear combined as above described
with mechanism for putting it out of action whenever the machine is running in a
straight course. Figure 5 is a side view and Figure 6 a plan view partly in section
of the same Figure 7 shews a side elevation of the mechanism for locking the axle
of one of the wheels to the tubular driving sleeve. In Figure 6 this mechanism is
shewn in section taken through the line A. A. Figure 7. In these figures the axles
and the parts of the differential gear are marked with the same letters of reference
as in Figures 1, 2 and 3. One axle is also shown to be tubular and the other
carried through it so as to give a continuous axle from one side of the machine to
the other G G are the hubs of the driving wheels one is fixed on the end of the
axle A and the other on the end of the tubular axle B..
The axles are received in bearings at H-I is the toothed wheel by which the
sleeve C is driven-K is a disc flange on the other end of the sleeve-K¹ are three
lumps standing out from the inner face of this disc-L are three curved levers, the
ends of which are received into and can turn in recesses formed in the lumps K as
seen in Figure 7-M is a disc collar keyed on the axle A-M³ is a flange projecting
inwards from the circumference of the disc and surrounding the disc K and levers
carried by it. N is a ring which lies against the disc K and which can turn
around the sleeve C-O is a ring which can not only turn around the sleeve C but
also slide along it-0¹ are three pins projecting from the ring O and entering holes
formed to receive them in the ring N-O is a pin projecting inwards from the
ring it enters an inclined slot P formed in the sleeve C so that when the ring O
is slidden along the sleeve it is also made to turn somewhat around it and when it
turns the ring N is forced to turn with it.
Around the circumference of the ring N are three inclines N'-the ends of the
levers L rest against these inclines. When the ring N is in such a position that
the ends of the levers rest against the ends of the inclines N¹ which are nearest to
the centre of the ring N the short arms or projections L' of the levers L do not
bear against the interior circumference of the flange M' of the disc M which is
keyed on the axle A-but when the ring N is turned so that the ends of the
inclines N' which are furthest, from the centre bear against the ends of the levers L
the short arms L' of these levers are made to bear against the interior circumference
of the flange M¹ and thereby to lock the sleeve C to the axle A. M is a ring for
closing in the levers L it is fixed by screws to the lumps K¹.
When the steering handle used for controlling the position of the steering wheel
is in its central position so that the machine runs in a straight course the ring 0
is kept in the position shewn at Figure 6. The axle A and sleeve C are then
locked together and the differential gear is out of action--but if the ring O is
moved end wise along the sleeve C away from the disc M. the levers L. L¹ no

page_text: longer lock the sleeve C to the axle and the differential gear then comes into
action.
At Figures 5 and 6 we have shown how the ring O can be caused to slide end-
wise along the sleeve C by the movement of the steering handle used for controlling
the position of the steering wheel
✗ is the steering handle used for controlling the movement of the steering
wheel-it may be arranged to control the movement of the wheel in any ordinary
manner. The axis of the steering handle is as is now usual set in a vertical
position.
On the axis of the handle X is a grooved cam Q into the groove of which enters
a pin on the end of one arm of crank lever R-the pin is in the highest part of
the groove when the handle is in its central position and the machine running in
a straight course-when however the handle is turned either to the right or left
the pin is depressed by the action of the cam groove upon it and the crank lever R
is thereby turned. The other arm of the crank lever is connected by a link S
with one arm of another crank lever T the other arm of which is forked to embrace
the ring O, and pins on the arms enter a groove formed around the circumference
of this ring. Consequently when the steering handle is turned from its central
position either to the right hand or to the left so as to steer the machine in either
one or the other direction the ring O is slidden away from the disc M and the
differential gear so allowed to come into action.
W is a spring fixed at one end to the framing of the machine and at the other
end carrying a V shaped tooth to enter a corresponding notch formed in the boss
on the axis of the steering handle in which the cam groove is cut-it enters the
notch when the steering handle is in its central position and serves to hold the
handle in this position so long as the machine is running in a straight course-
but if the steering handle is turned in either direction the spring gives way and no
longer locks the axis of the handle.
Having thus described the nature of our Invention and the manner of performing
the same we would have it understood that we claim :-
First. The construction of differential gear for velocipedes substantially in the
manner herein before described.
Second. The combination with differential gear for driving velocipedes of
mechanism for putting this gear out of action when the velocipede is running in a
straight course and for bringing it into action whenever the velocipede is directed
in a curved course substantially as described,
In witness whereof I the said William Thomas Shaw have hereunto set my
hand and seal this twenty-fifth day of July in the year of our Lord One thousand
eight hundred and eighty three.
WH THO SHAW. (LA)
.
WH THO SHAW.
(LA)