IMPROVE- MENTS IN THE CLASS OF TRICYCLES KNOWN AS "CONVERTIBLE SOCIABLES
Year: 1882

page_text: LETTERS PATENT to Isaac Thomas Townsend of Coventry in the County of
Warwick Bicycle and Tricycle Manufacturer for an Invention of IMPROVE-
MENTS IN THE CLASS OF TRICYCLES KNOWN AS "CONVERTIBLE SOCIABLES."
PROVISIONAL SPECIFICATION left by the said Isaac Thomas Townsend at
the Office of the Commissioners of Patents on the 5th August 1882.
ISAAC THOMAS TOWNSEND of Coventry in the County of Warwick "IMPROVE-
MENTS IN THAT CLASS OF TRICYCLES KNOWN AS "CONVERTIBLE SOCIABLES
"7">
My invention has particular reference to improvements in that class of tricycles
known as "convertible sociables" tricycles" and has for its object the production
of a tricycle which may be ridden by two riders of varying strength without any
liability of running to one side with equal advantages for one rider when
converted into a single machine.
Convertibles have hitherto been generally made with both the large wheels
driven by independent gear from each side that is the right hand rider has driven
the right wheel and the left hand rider the left wheel. This arrangement bas great
disadvantages two of which may be pointed out viz:-1st Both riders are scarcely
ever of the same strength or if they are they scarcely ever exert the same amount
of power at the same time, which is nearly the same thing. This causes the
machine to have constant tendency in a greater or less degree to turn to one side
or the other necessitating the continual and watchful use of the steering wheel
which at least is undesirable. 2nd In the building of the machine more weight
has to be placed on the steering wheel to ensure certainty and safety in its action
which of course means less weight on the driving wheel where it is most needed.
Now my invention overcomes these disadvantages by enabling me to always
apply the same power to both driving wheels however great the difference may be
in the strength of the riders, or the power applied by them in either its single or
double form ie for convertible sociable tricycles. This desirable result is obtained
in the following manner:-Take the machine in its form adapted for two riders.
It is composed of three main back bones as in my Patent "Four-in-hand" with a

page_text: partly tubular connecting bar under the saddles or seats and another connecting
bar at the front of the feet placed at a suitab'e elevation lower than the back one.
I fit double driving gear such as that known as Starleys or that protected by
myself to one side of the machine, either right or left, but preferably at the left
side where the Gentlemen would usually sit when accompanying a lady. The driving
shaft passes right across the machine is fast with the outside wheel and has the
appearance of a solid shaft while in fact it is not so as on one side the centre back
bone the shaft is divided into two parts by an ingenious coupling which when
drawn apart exposes an end exactly the same as the outside end for the purpose of
receiving the wheel from the ungeared end when converted into a single machine.
When convertible sociable machines are converted into single machines there is
necessarily a spare part of the frame and a spare seat has to be laid on one side for
the time. In the case of my new machine there is also a short piece of shaft which
is made hollow to fit over the end of the other part. The inside of this hollow
part is square to exactly fit the square on the shaft and to butt up against the
collar with either square or conical connecting shoulder. There is also immediately
behind the shoulder a connecting ferrule which is brought forward and screwed
tightly on to the outside of the socket completely encasing the collar and drawing
the socket tightly against it thus making a most complete and effective junction.
The treadle or crank shaft I also make in two parts by means of a neat junction
outside the centre bearing which I effect by making the central bearing sufficiently
thick to receive the square end of the removable portion of the shaft. To secure
these together effectively without vibration I insert a key crosswise through the
outside collar across the angle of the square neck of the removable crank shaft in
such a manner that the two bottom sides of the square neck are forced down upon
the corresponding sides of the socket. The key is parallel sideways but slightly
tapered in thickness. The form of this junction spigot may be somewhat varied
so as to have a three sided spigot the key in that case bearing on one flat side and
forcing the other two sides against the sides of the sockets as before explained.
The top and bottom connecting bars of the frame of the machine are likewise
connected together on one side of the centre back bone by a tapered reduced end
plug fitting exactly into a bored socket in the solid junction T pieces of the frame

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Isaac Thomas Townsend in the Great Seal Patent Office on the
5th February 1883.
"IMPROVE-
ISAAC THOMAS TOWNSEND of Coventry in the County of Warwick
MENTS IN THAT CLASS OF TRICYCLES KNOWN AS CONVERTIBLE SOCIABLES"
"
My invention has particular reference to improvements in that class of tricycles
known as convertible sociable tricycles and has for its object the production of a
tricycle which may be ridden by two riders of varying strength without any liability
of running to one side with equal advantages for one rider when converted into a
single machine.
Convertibles have hitherto been generally made with both the large wheels
driven by independent gear from each side, that is the right hand rider has driven
the right wheel and the left rider the left wheel. This arrangement has great
disadvantages two of which may be pointed out viz (1) Both riders are scarcely
ever of the same strength or if they are they scarcely ever exert the same amount
of power at the same time which is nearly the same thing. This causes the
machine to have a constant tendency, in a greater or less degree to turn to one
side or the other necessitating the continual watchful use of the steering wheel
which is at least undesirable. (2) In building the machine more weight has to be
placed on the steering wheel to ensure certainty and safety in its action which of
course means less weight on the driving wheels where it is most needed.
Now my invention overcomes these disadvantages by enabling me to always
apply the same power to both driving wheels however great the difference may be
in the strength of the riders or the power applied by them in either its single or
double form i.e for convertible sociable tricycles. This desirable result is obtained
in the following manner: Take the machine in its form adapted for two riders:
It is composed of three main back-bones as in my Patent "Four in Hand" with a
partly tubular connecting bar under the saddles or seats and another connecting
bar at the front of the feet placed at a suitable elevation lower than the back
one. I fit double driving gear such as that known as Starleys or that protected
by myself to one side of the machine, either right or left, but preferably at
the left side where the Gentleman would usually sit when accompanying a Lady.
The driving shaft passes right across the machine and is fast with the outside
wheel and has the appearance of a solid shaft while in fact it is not so as on one side
the centre back-bone the shaft is divided into two parts by an ingenious coupling
which when drawn apart exposes an end exactly the same as the outside end for
the purpose of receiving the wheel from the ungeared end when converted into a
single machine. When convertible sociable machines are converted into single
machines there is necessarily a spare part of the frame and a spare seat which
have to be laid on one side for the time. In the case of my new machine there is
also a short piece of shaft to lay aside which is made hollow to fit over the end of
the other part. The inside of this hollow part is square to exactly fit the square
on the shaft and to butt up against the collar with either square or conical
connecting shoulder. There is also immediately behind the shoulder a connecting
ferrule which is brought forward and screwed tightly on to the outside of the
socket completely encasing the collar and drawing the socket tightly against it
thus making a most complete and effective junction. The treadle or crank shaft I
also make in two parts by means of a neat junction outside the centre bearing
which I effect by making the central bearing sufficiently large to receive the square
end of the removable portion of the shaft. To secure these together effectively
without vibration I insert a key crosswise through the outside collar across the

page_text: angle of the square neck of the removable part of the crank shalt in such a manner
that the two bottom sides of the square neck are forced down upon the corre-
sponding sides of the socket. The key is parallel sideways but slightly tapered in
thickness. The form of this junction spigot may be varied so as to have a three
sided figure for the spigot, the key in that case bearing on one flat side and forcing
the other two sides against the sides of the socket as before explained. The top.
and bottom connecting bars of the frame of the machine are likewise connected
together on one side of the centre back-bone by a tapered reduced end plug fitting
exactly into a bored socket in the solid junction T pieces of the frame.
In order that my invention may be better understood and more readily carried
into practice I have appended hereunto two sheets of drawings showing various
modifications of doing so.
Figure 1 is a side elevation of one of my convertible sociables with the seats
and various handles removed as not being necessary in explaining my invention.
Figure 2 is a plan of the same machine with the various handles removed.
Indeed such details as are so generally known in the trade and which may be very
greatly varied without departing from the main features of the invention are
generally left out.
Figure 3 is a plan showing the machine converted from the double to the single
state.
Figure 4 to 17 are broken off detailed views of some of the various methods
which may be adopted for connections in carrying the invention out indeed the
remaining figures on the drawings are devoted to various modifications in the
details.
On the drawings A is the permanently fixed wheel to the No 1 or constant part
which is used for both double and single machine, and B is the removable one.
C is the permanent part of the shaft and D is the part which is removed when the
As the machine is
machine is in its single state i.e, it is absent in Figure 3.
shown by Figure 2 in its double condition the shafts C and D are so coupled as to
le practically one and is fast with the wheel B and is driven from the double
driving gear E which may be of several well known kinds but I prefer to use my
own as protected A.D 1881 No 1774 or that known as Starleys Patent No 3388
A.D 1877 but I do not confine myself to any particular driving gear so long as it
is of the double kind. It will thus be clearly understood that wheels A and B are
both driven and yet either may run faster than the other because the double
driving gear makes each wheel independent of the other. Two brakes are provided
i.e brake F for the left rider and G for the right rider. The steering rod H
passes up the centre of the machine and is accessible to both riders. The saddles
are attached to the connecting bars J and K. There are three bearings to the
main shaft viz c¹, c² and d'. For the purpose of strengthening the machine when
in its double state I generally use the stiffening bolt / shown by the part back
elevation Figure 7 which is removed with part 2 when altered to its single state.
This bolt greatly stiffens the machine at the joints near the centre back-bone J'.
The joints and j³ are simply the end tubes K and K2 with projecting plugs or
spigots fitting into the sockets which are fast with bars J and J. The crank or
pedal shaft M and M' are united together under the bar J in the enlarged centre
bearing so that they both move together and thus the most united action is secured
in both the front and back movements which is most important in double
machines the weight and impetus being considerably increased and therefore the
facilities for control should be just as effective in proportion to the weight as in
the single machines.
I will now explain how the machine is converted into a single one such as that
shown in plan by Figure 3: I withdraw the pins in joints j and j and the key P
or other device out of the junction of the pedal shaft which will be seen more
clearly at Figures 9 and 10. I then screw back nut o Figures 20 and 21 which is
secured in its position against the wheel B by the plate R and the screw pins, ₁
and so that the nut turns round forcing the wheel back off the square part of

page_text: the removable shaft D while the nut still remains in its position and it is thus
never lost while converting the machine, and it answers the double object of not
only drawing on the wheel but also of drawing it back. I then unscrew the nut N
which slides back against the journal cand thus the whole of part 2 is liberated
and may be withdrawn from part 1. Wheel B is then transferred to the square
end C of the permanent shaft C which is now exposed by the withdrawal of the
tube D. The nut o of the wheel is then screwed upon the end of the shaft C,
where its action is double as explained for D, which completes the conversion into
the single double driving machine as seen at Figure 3. The broken off end D³ is
of course an exact duplicate of end C allowing the wheel to fit up against the
collars C and D. The details of this coupled shaft may be clearly seen in
Figure 4 Sheet 2.
It will be manifest to any one acquainted with the trade that many varieties of
couplings may be substituted for the one shown by Figure 4 and which might in
some cases be even preferred and I have therefore shown several but not as
exhausting the variations, but as illustrating some of them as examples. There is
the one shown by Figures 9 and 10 where the square part m² on the crank
shaft M enters the collar M³ of the centre bearing on crank shaft M and is there
secured by the cross key P which forces the two angles m' and m³ to a firm
bearing in the collar or socket M³. Instead of the key P a screwed set pin S may
be used as shown in Figure 11 which has the same effect. Or the end of shaft M'
may be cut into a three sided form as shown by Figure 12 when either the key P
or set pin S may be used with similar effect. The clutch shown by Figures 13
and 14 would also form a very simple and effective joint and would very easily
separate. Or the coupling Figures 15 and 10 may be used with the three pins t, t¹
and t. Figure 17 is also a simple kind of coupling with the slots u sliding past
the pins of which there may be several-The shape of the shaft C in this case is
shown by dotted lines on the loose part D. Figures 5 and 6 illustrate a similar
coupling to the last one but with the tapered key W passing through to secure the
parts together and to keep them from turning. Figure 8 is simply a coupling in
two parts which may be screwed together so as to bind the end or ends to be
secured.
I also effect the same object by placing the double driving gear E on the N° 2
side of the centre back-bone J1 and by this means the shafts C and D though
connected by the double driving gear would also be capable of running at various
speeds the junction of the shafts being as before practically at the centre of the
machine. The loose wheel B may in this case have a separate cog or bevel
wheel carried fast to the loose wheel B to take the place of wheel Y Figure 18
which would come away with the spare part 2. Or the wheel Y may be carried
by a separate bearing on a second centre back-bone J' as shown by Figure 19 the
driving chain or other medium passing down to the crank shaft between the two
centre back bones J' and J7, but in this case the wheel B has a projecting piece Z
fitting into the loose shaft D corresponding with the hole in the wheel Y into
which it fits when in the single condition. We however prefer the driving gear
being at the side as most out of the way.
Tricycles for single riders with double driving gear are at the present time
widely used and many sociables have been built and used with double driving
gear also which is a simple matter but the difficulty of obtaining a convertible
sociable which should combine the double driving action in both its forms has
never before been overcome. Many riders have therefore preferred to purchase a
complete double driver single machine and a complete double driver sociable which
has at least two great disadvantages viz 1st There is more capital required and
2nd more storage room needed besides other disadvantages. I have therefore named
my new machine "The Dual Double Driver Convertible."
Having now described my said invention of improvements in that class of
tricycles known as "Convertible Sociables" and also how the same may be carried
into effect with several modifications illustrating the variations in detail which may

page_text: be adopted without departing from the principle of the invention I would have it
understood that what I claim is:
The construction of Tricycles known as "Convertible Sociables" with a main
shaft passing across the machine but coupled at or near its centre in such a manner
as to divide into a single tricycle so that the machine in both its double and single
condition is driven by double driving gear from one chain or other medium as
herein set forth.
In Witness whereof I the said Isaac Thomas Townsend have hereunto set
my hand and seal this second day of February in the year of our Lord
one thousand eight hundred and eighty three