IMPROVEMENTS IN TRICYCLES AND BICYCLES AND IN OTHER MACHINES IN WHICH CHANGE SPEED
Year: 1879

page_text: LETTERS PATENT to Henry Thomas Kirby of N° 4 Market Street Leicester
in the County of Leicester, Dentist, for an Invention of "IMPROVEMENTS IN
TRICYCLES AND BICYCLES AND IN OTHER MACHINES IN WHICH CHANGE SPEED
PROVISIONAL SPECIFICATION left by the said Henry Thomas Kirby at the
Office of the Commissioners of Patents on the 9th December 1879.
HENRY THOMAS KIRBY of N° 4 Market Street Leicester in the County of
Leicester, Dentist "IMPROVEMENTS IN TRICYCLES AND BICYCLES AND IN OTHER
MACHINES IN WHICH CHANGE SPEED GEAR AND DIFFERENTIAL DRIVING GEAR IS
REQUIRED
21
This invention has for its object improvements in tricycles and bicycles and in
other machines in which change speed gear and differential driving gear is
required.
I construct tricycles with a pair of large wheels and a small steering wheel in
front. The main wheels are mounted so that they can turn freely upon a straight
axle and the bosses of the wheel are continued as tubes towards the centre of the
machine where they are geared together by differential gear hereinafter described
for driving the two wheels simultaneously but leaving them free to vary in their
relative speeds of rotation The frame of the tricycle is founded upon a tube
carrying the bearings into which these elongated wheel bosses are received and
the bearings on either side of the differential gear are connected by a cage in which
this gear is enclosed. This cage is formed in connection with a framing which
descends from the axle inclining to the front and this framing carries an axis at its
lower end. Upon the axis there are treddles similar to the treddles of an ordinary
bicycle and these treddles through a system of gear herein after described give
motion to a chain wheel which is concentric with the treddle axis and between the
treddies. An endless driving chain passes around this chain wheel and also around
another corresponding chain wheel formed in connection with the differential gear
and concentric with the axle of the main wheels. The bearings of the main wheels
may be connected to the tube by a ball socket or other universal joint so that if
the tube or axle is slightly sprung no additional strain will be thrown on to the
bearings.

page_text: The steering wheel is carried by a part of the frame which when the machine is
in use is rigidly attached to the framing already described. This part of the frame
consists of a curved bar extending to the front and there receiving the stem of the
fork in which the steering wheel is held. There is also an upright springing from
the curved bar it extends upwards in front of the rider and aids in carrying the
seat. The upright at its upper end joins an horizontal bar and from the ends of
this bar stays pass to the tube carrying the bearings of the main wheels. In order
that the machine when out of use may be passed through narrow doorways these
stays are so applied that they can be readily disconnected and then the frame can
be folded or arranged so as to bring the fore part of the frame in a line with the
axle, the main wheels having first been removed. With the axle thus arranged
lengthwise the machine will readily pass through a narrow doorway To return
to the description of the machine as it is when set up for use; the steering is
effected by means of a handle at the upper end of a vertical axis placed imme-
diately in front of the upright of the frame. This axis at its lower end is furnished
with a pair of arms which are connected by links with a cross head upon the fork
of the steering wheel. The seat is carried on the top of a bow spring which is
connected by its fore end with the upright of the frame and at its hinder end the
spring is supported by a pair of inclined struts descending to the tube carrying the
'bearings of the main wheels. The struts are not attached directly to the bearings
but to a back leg or support which has a step upon it to aid in mounting to the
seat and which also serves as a break and as a safe guard against the machine
tipping backwards if carelessly ridden. This back leg is forked at its upper end
and it is jointed to projections formed to receive it on the upper sides of the tube
carrying the bearings of the main wheels.
The leg also projects for a short distance beyond these joints to the front and it
meets the two inclined struts which support the hinder end of the seat spring.
The back leg has a step upon it at a convenient distance from the ground and the
rider makes use of this step in mounting to the seat. The weight of the rider in
the seat acting through the struts upon the projecting fore ends of the leg causes
the hinder end of the leg to rise a short distance but not so far as to prevent the
leg at once checking any tendency to tip backwards. This back leg also serves as
an efficient brake capable of stopping the machine even on very steep inclines for
the rider has only to press his foot upon the step at the back as in commencing to
dismount, to cause the leg to bear firmly upon the surface of the road. I provide how-
ever another brake of which the arrangement is as follows:-Through the horizontal
bar at the top of the upright of the frame I pass an axis and at one end the axis
is provided with an arm with a palin upon it which by turning the axis can be
brought to bear on the periphery of one of the main wheels. The other wheel is
also controlled by a similar brake arm and this ann is formed with a boss which
enters into the end of the horizontal top bar of the frame. Thus the axis carrying
the one brake arm passes throughout the boss of the other arm but so as to be free
to turn. The brake handle is also mounted so as to be able to turn on the same
axis and the handle has at its fore end a cross head free to turn on the end of the
handle. The cross head has slotted holes at its ends and into one of these holes
there enters the end of an arm fixed upon the axis carrying one brake palin and
into the other the end of a similar arm formed upon the boss connected with the
other brake palm.
From this construction it results that when pressure is applied to the brake
handle both of the brake palms are caused to bear upon the periphery of the main
wheels and friction is applied to the two wheels equally. The arrangement may
be modified by applying a bevelled pinion on the brake handle and similar pinions
in gear with the tirst on the axis and boss in connection with the brake palms. In
tricycles intended to be used by ladies I arrange the frame somewhat differently
the bearings for the main wheels are at the upper ends of two uprights placed
immediately within the two wheels and connected at their lower ends by an hori-
zontal bar at a short distance from the ground. Another horizontal bar is attached

page_text: to this bar in the centre of the machine, it projects to the front and it has socketed
into it a bow iron which rises to and receives the stem of the steering wheel fork.
In this arrangement the steering is performed by means of a bandle fixed on the
upper end of the wheel fork and projecting back towards the seat which is imme-
diately over the axle. The differential gear of the main wheels and the change
speed gear on the treddle axis is, in this form of the machine, transferred from the
central position which it occupies in the Gentleman's tricycle to a position at the
side against one of the main wheels and the treddle axis is carried by its two ends
in bars which descend from the bearings of the main wheels to a cross bar con-
necting their lower ends with the longitudinal horizontal bar already mentioned.
The cross bar thus connecting the ends of the bars forming the treddle frame is
hollow and the brake axis is passed through it. The arrangement of the brakes to
obtain an equality of pressure on the two wheels is as already described The seat
is carried over the axle on a spring blade attached at its ends to standards rising
from the main bearings As in the Gentleman's tricycle the frame folds; for this
purpose the main wheels are in the same way removed and the treddle frame is
detached from the cross bar at its lower end. The vertical and horizontal portions
of the frame when thus set free fold together and the bow iron of the steering
wheel is turned a quarter round in its socket so that this wheel and the axle and
the wider parts of the frame are all brought approximately into one plane so thát
they may readily pass a narrow doorway.
The arrangement of the change speed gear is such that the rotary motion may
either be transmitted directly from the treddles to the chain wheel upon the
treddle axis or that the chain wheel may be driven from the treddle axis through
the interposed gear at one half the speed of the axis. The treddle axis has a
bevilled wheel fast upon it and this gears with another similar wheel carried upon
a stud within the chain wheel which is formed hollow and contains the bevelled
gear within it. There is also a third bevelled wheel mounted loosely on the
treddle axis and gearing with the bevelled wheel carried upon the stud within the
chain wheel; this third wheel is capable of being bolted fast either to the casing
in which it is contained (and which as before mentioned forms part of the chain
wheel) or it can be bolted to the frame carrying the treddle axis. In the former
position the treddle axis gives motion directly to the chain wheel and in the latter
position when the third bevilled wheel is held stationary the chain wheel is
carried round at the half velocity of the treddles
I employ a spring bolt for connecting the chain wheel and the bevilled wheel
and a hand lever bolt for rendering the bevilled wheel fast with the frame As
the lever bolt is inserted before it drops into the hole in the bevilled wheel it acts
upon an incline and withdraws the spring bolt. On the contrary when the lever
bolt is drawn back the spring bolt falls into its place.
According to another arrangement I employ spur pinions in place of bevilled;
there is one pinion fast on the treddle axis and two pinions on a stud within the
chain wheel but the stud is carried upon an independent disc free to turn upon the
treddle axis. There is also a fourth pinion fixed to the chain wheel and free to
revolve on the treddle axis.
Provision is made for locking the chain wheel to the free disc carrying the stud
pinions (in which case the whole of the gear revolves with the treddle axis) or for
locking the disc fast with the frame in which case the chain wheel revolves at a
slower rate than the treddle axis more or less according to the proportions of
the pinions.
To effect this locking a locking lever is provided upon the disc and a spring
causes this lever (when permitted) to engage by means of teeth formed upon it,
with the free pinion on the treddle axis. The further end of this lever projects
from the periphery of the disc through a hole which also serves to receive a bolt
to secure the disc to the frame and so to hold it stationary. This last mentioned
bolt is carried upon a lever and as it is inserted before it enters the hole in the
disc it strikes the end of the bolting lever carried upon the disc and moves it so
R 9742-1. Wt. 15746.

page_text: as to release the pinion on the treddle axis. On the contrary when the disc is
unbolted from the frame a spring presses forward the bolting lever which engages
and locks the pinion on the axis.
The arrangement of the differential gear is as follows:-
Fast with each of the main wheels there is a disc provided on one side with a
rim or flange and these face each other and teeth are formed within them. The
chain wheel is between the two discs and is capable of turning on the axle, it
carries upon it within its circumference a pair of spur pinions gearing together and
each of them also gears with one of the rings of internal teeth. This arrangement
causes the main wheels to be carried round with the chain wheel at a mean speed
equal to that of the chain wheel but it permits at the same time of occasional
variation in the relative speeds of the two wheels a similar arrangement may be
inade with an external instead of an internal ring of teeth. For the purpose of
readily connecting and disconnecting the main wheels from the axle I form a
groove around the axle at each end and I provide within the boss of each wheel
a pair of latches which closing together embrace the neck of the axle and secure the
wheel upon it. To lock the latches I arrange a ring to turn in the interior of the
boss and projection on this ring when it is turned to the locking position abutt
against the latches and prevent them separating or opening. A spring catch may
be applied to the ring to prevent it turning except when it is intended to
remove the wheel or to lock it in its place.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Henry Thomas Kirby in the Great Seal Patent Office on the
9th June 1880.
HENRY THOMAS KIRBY of N° 4 Market Street Leicester in the County of
Leicester Dentist "IMPROVEMENTS IN TRICYCLES AND BICYCLES AND IN OTHER
MACHINES IN WHICH CHANGE SPEED GEAR AND DIFFERENTIAL DRIVING GEAR IS
REQUIRED
"
This invention has for its object improvements in tricycles and bicycles and in
other machines in which change speed gear and differential driving gear is
required.
I construct tricycles with a pair of large wheels and a small steering wheel in
front. The main wheels are mounted so that they can turn freely upon a straight
axle and the bosses of the wheel are continued as tubes towards the centre of the
machine where they are geared together by differential gear hereinafter des
cribed for driving the two wheels simultaneously but leaving them free to vary
in their relative speeds of rotation. The frame of the tricycle is founded upon a
tube carrying the bearings into which these elongated wheel bosses are received
and the bearings on either side of the differential gear are connected by a cage in
which this gear is enclosed-This cage is formed in connection with a framing
which descends from the axle inclining to the front and this framing carries an
axis at its lower end. Upon the axis there are treddles similar to the treddles of
an ordinary bicycle and these treddles through a system of gear hereinafter des-
cribed give motion to a chain wheel which is concentric with the treddle axis and
between the treddles. An endless driving chain passes around this chain wheel and
also around another corresponding chain wheel formed in connection with the
differential gear and concentric with the axle of the main wheels.
The steering wheel is carried by a part of the frame which when the machine is
in use is rigidly attached to the framing already described. This part of the frame
consists of a curved bar or tube extending to the front and there receiving the
stem of the fork in which the steering wheel is held. There is also an upright
springing from the curve bar it extends upwards in front of the rider and aids in
carrying the seat. The upright at its upper end joins by a union joint an horizontal
bar and from the ends of this bar stays pass to the tube carrying the bearings of
the main wheels. In order that the machine when out of use may be passed
through narrow doorways these stays are so applied that they can turn around the
tubes to admit of the frame being folded. The folding is effected by bringing both
this and the fore part of the frame in a line with the axle the main wheels having
first been removed. With the axle thus arranged the machine will readily pass
through a narrow doorway. To return to the description of the machine as it is
when set up for use; the steering is effected by means of a handle at the upper end
of a vertical axis placed immediately in front of the upright of the frame. This
axis at its lower end is furnished with a pair of arms which are connected by links
with a cross head upon the fork of the steering wheel. The seat is carried on the
top of a bow spring which is connected by its fore end with the upright of the
frame and at its hinder end the spring is supported by a pair of struts descending
to a back leg or support which has a step upon it to aid in mounting to the seat
and which also serves as a break and as a safeguard against the machine tipping
backwards if carelessly ridden. This back leg is forked at its upper end and it is
jointed to projections formed to receive it on the upper sides of the tube carrying
the bearings of the main wheels.
The leg also projects for a short distance beyond these joints to the front and it
meets the two inclined struts which support the hinder end of the seat spring. The
back leg has a step upon it at a convenient distance from the ground and the rider

page_text: makes use of this step in mounting to the seat. The weight of the rider in the
seat acting through the struts upon the projecting fore ends of the leg causes the
hinder end of the leg to rise a short distance but not so far as to prevent the leg at
once checking any tendency to tip backwards. This back leg also serves as an
efficient break capable of stopping the machine even on very steep inclines for the
rider has only to press his foot upon the step at the back as in commencing to
dismount to cause the leg to bear firmly upon the surface of the road. I provide
however another break of which the arrangement is as follows: Through the
horizontal bar at the top of the upright of the frame I pass an axis and at one end
the axis is provided with an arm with a palm upon it which by turning the axis
can be brought to bear on the periphery of one of the main wheels-The other
wheel is also controlled by a similar brake arm and this arm is formed with a boss
which enters into the end of the horizontal top bar of the frame-Thus the axis
carrying the one brake arm passes throughout the boss of the other arm but so as
to be free to turn. The brake handle is also mounted so as to be able to turn on
the same axis and the handle has at its fore end a cross bead free to turn on the
end of the handlo. The cross head has slotted holes at its ends and into one of
these holes there enters the end of an arm fixed upon the axis carrying one brake
palm and into the other the end of a similar arm formed upon the boss connected
with the other brake palm.
From this construction it results that when pressure is applied to the brake
handle both of the brake palms are caused to bear upon the periphery of the main
wheels and friction is applied to the two wheels equally. The arrangement may
be modified by applying a bevilled pinion on the brake handle and similar
pinions in gear with the first on the axis and boss in connection with the brake
palins.
In tricycles intended to be used by ladies I arrange the frame somewhat
differently; the bearings for the main wheels are at the upper ends of two uprights
placed immediately within the two wheels and connected at their lower ends by
an horizontal bar at a short distance from the ground. Another horizontal bar is
attached to this bar in the centre of the machine it projects to the front and it has
socketted into it a bow iron which rises to and receives the stem of the steering
wheel fork. In this arrangement the steering is performed by means of a handle
fixed on the upper end of the wheel fork and projecting back towards the seat
which is immediately over the axle. The differential gear of the main wheels and
the change speed gear on the treddle axis is in this form of the machine, transferred
from the central position which it occupies in the Gentleman's bicycle to a position
at the side against one of the main wheels and the treddle axis is carried by its
two ends in bars which descend from the bearings of the main wheels to a cross
bar connecting their lower ends with the longitudinal horizontal bar already
mentioned. The cross bar thus connecting the ends of the bars forming the treddle
frame is hollow and the brake axis is passed through it. The arrangement of the
brakes to obtain an equality of pressure on the two wheels is as already described.
The seat is carried over the axle on a spring blade attached at its ends to standards
rising from the main bearings. As in the Gentleman's tricycle the frame folds; for
this purpose the main wheels are in the same way removed and the treddle frame
is detached at its lower end. The vertical and horizontal portions of the frame
when thus set free fold together and the bow iron of the steering wheel is turned a
quarter round in its socket so that this wheel and the axle and the wider parts of
the frame are all brought approximately into one plane so that they may readily
pass a narrow doorway.
The arrangement of the change speed gear is such that the rotary motion may
either be transmitted directly from the treddles to the chain wheel upon the treddle
axis or that the chain wheel may be driven from the treddle axis through the
interposed gear at one half the speed of the axis. The treddle axis has a bevilled
wheel fast upon it and this gears with another similar wheel carried upon a stud
within the chain wheel which is formed hollow and contains the bevilled gear

page_text: within it. There is also a third bevilled wheel mounted loosely on the treddle axis
and gearing with the bevilled wheel carried upon the stud within the chain wheel;
this third wheel is capable of being bolted fast either to the casing in which it is
contained (and which as before mentioned forms part of the chain wheel) or it can
be bolted to the frame carrying the treddle axis. In the former position the treddle
axis gives motion directly to the chain wheel and in the latter position when the
third bevilled wheel is held stationary the chain wheel is carried round at the half
velocity of the treddles. I employ a spring bolt for connecting the chain wheel
and the bevilled wheel and a hand lever bolt for rendering the bevilled wheel fast
with the frame. As the lever bolt is inserted before it drops into the hole in
the bevilled wheel it acts upon an incline and withdraws the spring bolt. On
the contrary when the lever bolt is drawn back the spring bolt falls into its
place.
According to another arrangement I employ spur pinions in place of bevilled,
there is one pinion fast on the treddle axis and two pinions on a stud with in the
chain wheel but the stud is carried upon an independent disc free to turn upon the
treddle axis. There is also a fourth pinion fixed to the chain wheel and free to
revolve on the treddle axis. Provision is made for locking the chain wheel to the
free disc carrying the stud pinions (in which case the whole of the gear revolves
with the treddle axis) or for locking the disc fast with the frame in which case the
chain wheel revolves at a slower rate than the treddle axis more or less according to
the proportions of the pinions. To effect this locking a locking lever is provided
upon the disc and a spring causes this lever (when permitted) to engage by means
of teeth formed upon it, with the free pinion on the treddle axis. The further end
of this lever projects from the periphery of the disc through a hole which also
serves to receive a bolt to secure the disc to the frame and so to hold it stationary.
This last mentioned bolt is carried upon a lever and as it is inserted before it enters
a hole in the disc it strikes the end of the bolting lever carried upon the disc and
moves it so as to release the pinion on the treddle axis. On the contrary when the
disc is unbolted from the frame a spring presses forward the bolting lever which
engages and locks the pinion on the axis.
The arrangement of the differential gear is as follows:-
Fast with each of the main wheels there is a disc provided on one side with a
rim or flange and these face each other and teeth are formed within them. The
chain wheel is between the two discs and is capable of turning on the axle; it carries
upon it within its circumference a pair of spur pinions gearing together and each
of them also gears with one of the rings of internal teeth. This arrangement causes
the main wheels to be carried round with the chain wheel at a mean speed equal
to that of the chain wheel but it permits at the same time of occasional variation
in the relative speeds of the two wheels a similar arrangement can be made with
an external instead of an internal ring of teeth-For the purpose of readily
connecting and disconnecting the main wheels from the axle I form a groove around
the axle at each end and I provide within the boss of each wheel a pair of latches
which closing together embrace the neck of the axle and secure the wheel upon it.
To lock the latches I arrange a ring to turn in the interior of the boss and projec-
tions on this ring when it is turned to the locking position abutt against the latches
and prevent them separating or opening. A spring catch may be applied to the
ring to prevent it turning except when it is intended to remove the wheel or to
lock it in its place.
In order that my said invention may be most fully understood and readily
carried into effect I will proceed to describe the Drawings hereunto annexed.

page_text: wheels and b is the steering wheel. The wheels a are mounted on a straight axle
passing through from side to side within tubes attached to the wheel bosses. These
tubes each terminate in a disc a. c is a chain wheel between the discs a¹ it is
free to revolve (or it may be fixed) on the straight axle and is connected with the
discs by differential gear hereinafter described. a² is an outer tube on which the
frame of the tricycle is founded. This tube is in two parts one on either side of
the machine and the parts are connected by means of the open framing d. The
framing & projects downwards in an inclined direction and carries at its lower end
in suitable bearings the treddle axis e. e are the treddles on the axis e. There is
a chain wheel ƒ on the treddle axis which is driven from the axis by change speed
gear hereinafter described. A pitch chain g encircles the chain wheels c and f.
h is a curved bar forming part of the frame and having an upright h' springing
from it. The hinder end of the bar h is received into sockets d¹. d. formed in cou-
nection with the frame d and when the machine is in use this attachment is
rendered rigid by a clip binding the upright ¹ to a horn d' on the frame. The
stem of the steering wheel is held in a socket formed at the leading end of the
bar h. At the top of the upright A' an horizontal tubular bar i is connected by
means of a screw union at and from the outer ends of this bar the stays k. k.
pass down to the tube a² of the frame where they are attached by joints and they
can turn on the tubes so that the parts of the machine may fold together as is
represented at Figure 4. The fork of the steering wheel has a cross bend upon its
upper end and from the extremities of the cross head two light rods pass to a
similar piece at the lower end of the steering axis L. The steering axis passes
up parallel to the upright h¹ and is held in bearings projecting out from this
upright. The steering handle is fixed upon the top of the axis L. m is a clip on
the upright, it has one end of the bow spring n jointed to it and the other end
of the spring is jointed to the struts o. o. The saddle or seat p is secured to the
middle of the bow spring n. g is a back leg or support having a step g¹ on it to
aid in mounting. This leg also renders it impossible that the machine should fall
backwards; it is also available as a brake ae already stated. The leg 7 is jointed
to the frame d at q". q. the leg being forked at the upper end. The two prongs
into which the leg 9 divides are continued beyond the joint q" and are connected
as is shown with the lower ends of the struts o. o. so that the weight of the rider
on the saddle causes the leg to be lifted a short way from the ground. The arrange-
ment of the connections between the seat and the back leg admits of variation
whilst still retaining the peculiar feature that the downward notion of the seat
when the weight of the rider comes upon it causes an upward movement of tho
leg and lifts it off the ground. The machine is also provided with a brake operated
by means of the hand lever r; when this handle is pressed down it operates in n
manner hereinafter described to cause the palins 8. 8. to be pressed against the
periphories of the wheels a. a.
For the purpose of folding the frame the main wheels a. a. are removed; the bow
spring n and the upright are separated; the union joint at is uncoupled and
the clip which secures the horn d to the upright his slackened and lifted. Then
the horizontal tubular bar i is thrown to the rear, the staysk turning about the
axle and the bar h which forms the fore part of the frame is turned one quarter
round in the sockets at d. d. so that the plane in which it lies is parallel with the
axle. The other parts fold into the positions indicated in Figure 4.
It will be observed that when the frame is folded the principal parts all lie with
their length in the same direction; this is brought about by turning the fore part
of the frame one quarter round as described and thereby bringing it parallel to the
axle. The details may be varied so long as this feature is retained.
Figure 5 is a side elevation and Figure 6 is a back elevation of a tricycle very
similar to that shown by the Figures 1. 2. 3 and 4 but the frame is of lighter
construction and is not adapted to be folded to a smaller width. The modifications
in the form of the frame are clearly indicated by the Drawings. In order as far
as possible to combine rigidity with lightness, strained wires are employed to

page_text: brace the frame. The brakes are not shown as applied to this tricycle which is
mainly intended for racing on a track kept for the purpose and under such
conditions brakes are not needed. The steering handle of this tricycle is arranged
to turn upon an horizontal stud projecting in front of the upright of the frame and
the handle is connected by cords or wires passing around pulleys with the cross
head upon the fork of the steering wheel. The change speed gear in connection
with the treddle axis is dispensed with, the chain wheelf being keyed directly
upon this axis. A driving chain transmits the motion from the wheelf to the
chain wheel c and differential gear connects the wheel c with the main wheels a. a.
as in the vehicle shown by the Figures 1. 2. 3 and 4. and as is hereinafter more
fully described.
Figure 7 is a side elevation, Figure 8 is a back elevation, Figure 9 is a plan,
of a tricycle adapted to be used by a lady. Figure 10 represents the same tricycle
folded.
a. a. are two tubular uprights to which at their upper end the bearings for the
main wheels are fixed. b is an horizontal tube connecting at the lower ends the
uprights a. a. c is a hollow bar connected with the bar b in the centre and
extending forwards, at its end is a socket into which the stem of the bow iron &
is received and fixed. When the tricycle is folded the bow iron d is turned one
quarter round in its socket to the position indicated in Figure 10. The bow iron d
has a socket at its upper end into which the stem of the fork of the steering wheel
is received and above the socket a steering handle e is fixed upon the stem of the
fork; so that this tricycle steers in the same way as a Bath chair. The treddle
frame is composed of two inclined tubular bars or stays f which descend from the
bearings of the main wheels to the outer ends of a transverse horizontal bar g.
The bar g is, when the vehicle is in use, attached to the bar c but the attachment
is made in such a manner that the bar g may be readily disconnected from the
bar c so that the tricycle may be folded in the manner shown in Figure 10 in
which form it will readily pass through narrow door ways. It will be seen that
the uprights a. a. also fold down parallel to the bar c. It is obvious that the
disconnection for folding may be made at either of the other of the angles of the
triangular frame; but the arrangement shown is preferred. is the treddle axis it
is cranked and at its ends it is received into bearings formed for it upon the
inclined tubular bars or stays f. f. i is a chain wheel with change speed gear;
these parts are mounted upon the treddle axis as in the tricycles already described
but on one side in place of in the centre of the vehicle. The main wheels are
driven from the treddle axis by means of a driving chain passing around the chain
wheel at and also around another chain wheel at k which actuates the main
wheels of the vehicle as in the other tricycles and as is hereinafter more fully
described; but in this tricycle the differential gear is at the side of the vehicle in
order to leave a freer space in the middle for the seat and the rider. is the seat,
it is fixed to the middle part of a spring m which at its ends is connected by
links with standards fl.fl. These standards are formed as continuations of the
two inclined bars or stays f. f.
Figures 11 and 12 show to a larger scale one of the methods for arranging the
speed gear upon the treddle axis.
Figure 11 is a section in the plane of the axis and Figure 12 is an elevation
with the treddle axis in section. a is the treddle axis and b is a bevilled wheel
fast upon it.
c is the chain wheel it is formed with a large hollow boss c' within
which the gear wheels are contained. The wheel and boss c. c. are mounted so
that they may turn freely on the axis a. c¹¹ is a stud within the boss c¹ and on this
stud the bevilled wheel d is carried. The wheel & gears with another wheel
which also is able to turn freely upon the treddle axis a and it is formed with a
flange fitting within the boss c so that in this way the gear wheels are
completely boxed in. f. f. are portions of the framing upon which the bearings
for the treddle axis are formed. g is a lever bolt connected with the frame ƒ by
a stud at g¹ about which the lever bolt is able to turn. The lever bolt can be

page_text: operated by a cord or other like connection at one end by which its other end can
be made to enter a notch in the periphery of the wheel e and so to lock the wheel e
fast with the frame of the vehicle; this is the position when the slow speed is
required. Also upon the wheel e a lever his carried, a bolt h' is jointed to the
lever and a spring h¹ tends to cause the bolt h¹ to protrude through the flange of
the wheel e and to enter a hole formed to receive it in the hollow boss c' of the
chain wheel c. When the bolt h¹ enters the hole in the boss c¹ the wheels c and e
are bolted together and this is the position when the faster speed is required. It
is necessary that the bolt should be withdrawn before the lever bolt g engages
with the flange of the wheel e; to ensure this the lever his formed with a head
which projects through the opening in the flange of the wheel e hence the end of
the lever bolt g cannot enter the oponing without first displacing the lever h and
BO drawing back the bolt h. On the other hand as soon as the lever bolt g is
withdrawn the spring h¹¹ causes the bolt h' again to engage with the boss of the
chain wheel c. Figures 13 and 14 show another way in which the locking bolts
may be arranged. Here the bolt g enters from the side, the stem of the bolt is a
spring and the bolt enters the hole formed for it in the flange of the wheel e when-
ever it is permitted to do so. An incline operated by a hand connection keeps the
bolt back when the faster speed is required. The bolt his forced outwards in a
radial direction by a bow spring and when free enters a hole in the boss of the
chain wheel c thereby locking the wheels cand e together, but this bolt is with-
drawn whenever the bolt g is permitted to advance, for then the end of the bolt g
comes against the cam piece h* fixed upon the bolt h¹. In this way the bolt h' is
displaced before the bolt g can engage.
Figures 15 and 16 show another arrangement of the change speed gear. Figure 15
is a section in the plane of the treddle axis and Figure 16 is a side elevation with
the axis in section. a is the treddle axis and b is a pinion fast upon it. c is a disc
free to turn upon the treddle axis; this disc (with the aid of the inner frame c¹)
supports the stud c". d and d' are two pinions formed of a piece and mounted so
as to be able to turn upon the stud c". The pinion d gears with the pinion b on
the treddle axis whilst the pinion d' gears with and drives the pinion e which is
fixed to the boss of the chain wheel fand can revolve upon the axis a.
The disc c
and frame c¹ carry also the axis of a locking lever g, on one end of this lever there
is a projection which engages with the teeth of the pinion e whenever the locking
lever is uncontrolled otherwise than by its spring g¹. The other end of the lever g
passes out through an opening in the periphery of the disc c and into the saine
opening the end of another bolting lever his caused to enter when it is desired that
the disc c should remain stationary; as it is required to do when the slower speed
gear is in operation. The bolt lever h turns upon a pin fixed to the main frame (as
is described in respect to Figures 11 and 12) and the bolt h before it can drop in
is made to draw back the bolt g as previously described.
These change speed gears are very applicable for use in bicycles; in which case
the gear box forms the centre or boss of the main wheel of the bicycle.
It will be obvious that by slight alteratious these arrangements may be made to
change speed from that of a running shaft to a higher speed instead of a slower; in
tricycles and bicycles however this is not required.
Figures 17. 18 and 19 show the arrangement of the differential gear which I
employ upon the main axle. Figure 17 is a section in the plane of the axle,
Figure 18 is a side elevation with the axle in section and Figure 19 is a plan. a is
the main axle b'..6". are tubes surrounding the axle and fast with the bosses of
the main wheels of the vehicle. c. c. are discs fixed upon the tubes b¹. b. The
discs c. c. have internal teeth formed upon them at c. c. and there are two pinions
d and e which gear into these rings of teeth, one pinion gearing with the one ring
of teeth and the other with the other ring. The pinions d and e also gear with
each other. f is the chain wheel between the discs c. c., it is free to turn upon
the main axle and it carries by suitable attachments the stud axes of the pinions &
and e. By this arrangement of gear it will be seen that the main wheels can revolve

page_text: at different speeds although both are driven by the chain wheel f. This arrange-
ment may be varied by substituting external gear for the internal teeth at c. c'. the
pinions & and e being then on the outside.
Figures 17. 18 and 19 shew the wheels connected with the differential gear by
means of tubes over a solid axle but I have adopted another plan shewn at
Figure 20, in this there is a ball bearing a about the centre of the machine and the
axle is divided into two parts 6. b. and the driving wheels are attached to each
axle by means of a key or feather and thumb nut, or a cone and nut. The axle b¹
has the wheel attached at one end and this axle passes inwards through the main
bearings till it reaches the differential gear, the first wheel c of which is keyed or
attached to the axle. The axle b¹ has next the chain wheel d loose on it, then the
other wheel e also loose. The boss of the wheel e has a ball bearing to support it.
The shaft 6 passes a short distance beyond the boss of the wheel and is coupled with
the shaft b to which the other driving wheel is attached, by means of a short
clutch box. The clutch box while it pivots on the first mentioned and longest
shaft or axle also clutches into the boss of the wheel e of the differential gear and
as it is free to turn on the first named axle it is clutched into the second axle, the
chain wheel when moved gives motion to both driving wheels through the axles.
Figures 21 and 22 represent the arrangement by which the main wheels are
readily detachable from the axle. Figure 21 is a section in the plane of the axle
and Figure 22 is an end elevation. a is the wheel boss, it is formed with discs or
flanges a¹. a¹¹, one at either end. b is the axle, c is a tube surrounding the axle
and carrying a disc c¹. In the face of the disc e' there are holes to receive pegs
projecting from the face of the flange a¹ of the wheel boss. d. d. are two latches
connected with the flange all of the wheel boss by the studs d'. d. on which the
latches are able to turn. The latches when closed together embrace the axle by a
neck formed upon it at a close to the end. The latches when in place are locked
by a turning ring e which is confined against the face of the flange a" by the studs
d. d. The locking ring lays in a recess in the flange a" and by turning it partly
round inclines on the ring are caused to bear against the backs of the latches.
e. e. are spring catches upon the ring entering recesses in the flange all to retain
the locking ring e in the position in which it may be placed. This latch arrange-
ment may be applied in connection with the divided axle represented in Figure 20.
The wheels in this case are driven by the axle with which they are connected by a
key and feather and then I apply nuts upon the ends of the axle. To set the
wheels up tightly on the axle the nuts are screwed home against the latches. In
removing the wheels the nuts are slackened but not removed and the latches
opening allow the wheels to pass off from the ends of the axle over the nuts.
The Figures 23 and 24 relate to the arrangement of the brake.
Figure 23 is an horizontal section and Figure 24 is a side view partly in
section.
a is a hollow cross bar of the frame through which an axis b passes. Upon its
further end this axis has a fixed arm carrying a palm to bear upon the periphery of
the main wheel as already described. bis another arm fixed upon the axis bits
end is received into an elongated hole in the cross head c.
The cross heal c is
mounted so that it can turn on the end of the hand lever d and this lever is
mounted upon and is able to turn around the axis b. e is a boss which is received
into the end of the tube a where it is so held as to be able to turn; it has upon it
two arms e¹ and e¹¹. The arm el projects to the rear passes over the handle d and
carries a palm which it brings to bear against the periphery of the main wheel on
this side of the machine. The other arm el projects to the front and its end enters
an elongated hole in the cross head c but at the opposite end to that into which
the end of the arm b¹ is received. By this arrangement it results that pressure
exerted upon the handle d is imparted equally by the brake palms to the periphories
of the two main wheels.
Figures 25 and 26 show in detail the arrangements for supporting the seat in
the tricycle represented by the Figures 5 and 6.

page_text: Figure 27 shows in detail the arrangement of the back leg of the tricycle
represented by the Figures 1. 2. 3 and 4.
Having thus described the nature of my said invention and the manner of
performing the same I would have it understood that I claim :-
First The construction of tricycles and like vehicles with change speed gear upon
the treddle axis giving motion to a chain wheel, such chain wheel by means of a
driving chain actuating another chain wheel geared with the main wheels of the
vehicle by differential gear substantially as described.
Second-The construction of tricycles with folding frames substantially as
described in respect to Figures 1. 2. 3. 4 and Figures 7. 8. 9 and 10.
Third The change speed gear substantially as described in respect to Figures
11. 12. 13 and 14 applicable to tricycles bicycles and other machinca.
Fourth-The change speed gear substantially as described in respect to Figures
15 and 16, applicable to tricycles, bicycles and other machines.
Fifth. The differential gear substantially as described in respect to Figures 18.
19 and 20 applicable to tricycles and other machines.
Sixth-The differential brake apparatus for tricycles by which pressure is equally
applied to the peripheries of the two main wheels substantially as described in
respect to Figures 23 and 24.
Seventh The application to tricycles of a back leg operating in connection with
the seat substantially as described in respect to Figures 1. 2. 3. 4 and 27.
Eighth The arrangement of latches and locking ring by which the main wheels
are readily connected and disconnected substantially as described in respect to
Figures 21 and 22.
Ninth The construction of tricycles substantially as described and represented
by the annexed Drawings.
In witness whereof I the said Henry Thomas Kirby have hereunto set my hand
and seal this seventh day of June in the year of our Lord One thousand eight
hundred and eighty.
HENRY THOMAS KIRBY (L.S.)