IMPROVEMENTS IN CONVERTIBLE TANDEM TRICYCLES
Year: 1885

page_text: I ISAAC THOMAS TOWNSEND of West Orchard Works, Coventry in the County
of Warwickshire, Cycle Manufacturer, do hereby declare the nature of my said
invention for "IMPROVEMENTS IN CONVERTIBLE TANDEM TRICYCLES," to be as
follows:-
The object of my invention is the construction of a central driving front
steering tandem tricycle, which can readily, and easily be converted into a single
machine. The only detachable arrangement used for the conversion of a central
driving front steering tandem, is that known as the "Krao" or other modifications
of the same which consists in attaching to the frame of an ordinary front steering
central driven tricycle, by a transverse, and vertical joint, an auxiliary frame with
a fourth wheel carrying a seat or saddle, handles, and pedal crank driving gear, for
the second rider. There are many objections to this type of machine the principal
of which are, First;-The bad disposition of the wheel load which places the bulk
of the weight on the small wheels. Secondly:-The trailing wheel not being
under direct control, is susceptible of defection from the vertical joint in passing
over uneven ground thereby setting up oscillation and sensibly affecting the
steering of the machine; and Thirdly;-The complication of the transverse and
vertical joints necessary to allow the trailing wheel to accommodate itself to
uneven surfaces and to trail to follow the steering of the machine.
In a machine constructed according to my invention all these evils are overcome,
the convertible portion which is of less weight, is rigidly fixed to the main portion
of the frame of the machine and is readily detached therefrom; a greater distance
is obtained between the riders, and the wheel load is all brought to bear upon the
driving wheels, beyond what is actually necessary to give steadiness to the steering
wheel.
I construct my machine as follows:-I take a central driving front steering
tricycle of the usual pattern but with an extended front so that the position of the
rider is more in advance of the axle carrying the driving wheels than is usually
the case. I prefer to place the differential or balance gear in the centre of the axle
and to support the axle by three or more bearings. I therefore form the main part
of the frame of the machine to which the bowsprit tube which carries the pedal
crank axle, and the steering wheel is fixed, of a suitable shape to carry these
bearings and I extend this frame backwards to carry the detachable part of the

page_text: frame; which consists of a single tube running downwards and slightly rearwards
to carry the pedal crank axle and terminating so as to form a back stay, and
upwards to carry the transverse handle bar and a short rigid back bone to carry
the saddle. This detachable frame carries a taper shank or plug which fits into a
corresponding socket in the centre of the extended main frame of the machine, and
is fixed thereto by a set screw, lock nut, or other mechanical equivalent, any
suitable method being adopted to prevent the shank on the detachable frame
turning round in the socket, by the oscillation of the rider; the detachable frame
is also tied or stayed to the main frame by a light rod with hooked ends which are
dropped through two holes in brackets fixed to afy convenient parts of the frames,
and is drawn up taut by a right and left hand nut in the centre of its length, or by
any other equivalent arrangement.
The side tubes of the extended main frame are carried backwards so as to carry
detachable sockets carrying vertical spade handles, one of which may be a rack and
pinion steering handle, connected with the front steering gear by any convenient
arrangement which can be readily detached. The transverse handle bar is adjust-
able vertically and is also detachable so that it may be removed when the vertical
spade handles are used, to allow the rear rider to have control of the steering as
well as the front one.

page_text: I ISAAC THOMAS TOWNSEND of West Orchard Works, Coventry in the County
of Warwickshire, Cycle Manufacturer do hereby declare the nature of this invention
and in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement:-
"
The object of my invention is the construction of a central driving front steering
tandem tricycle which can readily and easily be converted into a single machine.
The only detachable arrangement used for the conversion of a central driving front
steering tandem, in which the whole of the parts necessary for the extra rider are
self contained on a frame that can be attached and detached complete in itself, is
that known as the "Krao or other modifications of the same; which consists in
attaching to the frame of an ordinary front steering central driving tricycle, by a
transverse and vertical joint, an auxiliary frame with a fourth wheel carrying a
seat or saddle, handles, and pedal crank driving gear for the second rider. There
are many objections to this type of machine, the principal of which are; First:-
The bad disposition of the wheel load which places the bulk of the weight on the
small wheels Secondly:-The trailing wheel not being under direct-control, is
susceptible of deflection from the vertical joint in passing over uneven, ground,
thereby setting up oscillation, and sensibly affecting the steering of the machine,
and Thirdly-The complication of the transverse and vertical joints necessary to
allow the trailing wheel to accommodate itself to uneven surfaces, and to trail to
follow the steering of the machine.
In a machine constructed according to my invention all these evils are overcome,
the convertible portion, which is of less weight, is rigidly fixed to the maine frame
of the machine, and is readily detached therefrom; a greater distance is obtained
between the riders; and the wheel load is all brought upon the driving wheels,
beyond what is actually necessary to give steadiness to the steering wheel.
I construct my machine as follows I take a central driving front steering tricycle
of the usual pattern, but with an extended front, so that the position of the front
rider is more in advance of the axle carrying the driving wheels than is usually
the case I form the main part of the frame of the machine to which the bowsprit
tube which carrys the pedal crank axle and the steering wheel, is fixed, of a suitable
shape to carry the bearings, the seat support, and the vertical spade handles, and
I fix to it in a manner that I will presently describe the detachable part of the
frame, which consists of a single tube running downwards and slightly rearwards
to carry the pedal crank axle, and terminating so as to form a back stay, and
upwards to carry the transverse handle bar and a short rigid backbone to carry the
saddle support. This detachable frame carries a taper shank or plug which fits
into a corresponding socket in the centre of the main frame of the machine, and
is fixed thereto by a set screw and lock nut, the end of the set screw being coned.
to take in a countersunk hole in the shank of the detachable frame to prevent it
twisting round in the socket by the oscillation of the rider. The detachable frame
is also tied or stayed to the main frame by a light rod with hooked ends, which
are dropped through two holes in brackets fixed to any convenient parts of the

page_text: two frames. This rod is made in two pieces, joined by a nut having a right and
left hand thread, so that by turning the nut the rod may be drawn up taut to stay
the frames together. On the ends of the transverse tube forming the rear part of
the main frame are formed sockets to receive the shanks of detachable brackets
carrying vertical spade bandles, one of which is a rack and pinion steering handle,
the pinion of which is connected with the rack of the front steering gear by an
extension of the rack which is capable of being readily attached and detached.
The transverse handle bar is adjustable vertically, and is also detachable, so that
it may be removed when the vertical spade handles are used to allow the rear rider
to have control of the steering, as well as the front one.
In order that my invention may be fully understood, I will more particularly
describe it with the aid of the accompanying drawings, throughout the several
views of which, similar parts are marked with like letters of reference.
Fig. 1 Sheet No 1. is a side elevation of my tandem tricycle Fig. 2; Sheet No 2
is a side elevation of my tricycle in its single form with the detachable frame
removed. Fig. 3 Sheet No 2 is a side elevation of the detachable frame. Fig. 4
Sheet No 2 is a side elevation of one of the detachable brackets carrying one of
the vertical spade handles for the rear rider. Fig. 5 Sheet No 3 is a plan of the
frame of my tandem tricycle. Figs. 6 and 7 Sheet No 3 are a sectional elivation,
and a plan, respectively on an enlarged scale, of the shank and socket for attaching
the detachable frame to the main frame. Throughout these views all the parts
unnecessary for the description of my invention, and which present no novel
features, have been for the sake of clearness.
Referring to the drawings A designates the main frame of the tricycle, which is
made of greater length than usual. B designates the axle carrying the driving
wheels C, C, and running in suitable bearings D, D. E designates the steering
wheel, mounted in a fork F connected to the main frame A of the machine, by the
usual vertical joint or head. G designates the pedal crank axle mounted in
Buitable bearings carried by the bracket H, and connected to the main axle by the
usual chain and chain wheels. J designates the seat support of the front rider,
and K the saddle thereof. L, L, designate the vertical spade handles for the front
rider, one of the handles being free to turn in its socket and is provided with a
pinion that gears with the usual rack steering rod M connected to the fork F
carrying the steering wheel. A¹ designates the detachable frame which is provided
with a taper shank a¹ which fits into a taper socket a formed in the centre of the
main frame A and is fixed thereto by the set screw a² the coned end of which
engages with a contersunk recess a³ in the taper shank a¹. The detachable frame A'
consists of a tube extending upwards to receive the shank N of the transverse
handle bar O, and downwards to support the bracket H¹ carrying the pedal crank
axle G¹ which is connected with the axle B by the usual chain and chain wheels
and it terminates in a small safety wheel P forming a backstay. J designates the
seat support and K¹ the saddle for the rear rider, the former being carried in a
socket formed at the end of a short rigid arm running out from the tube forming
the frame A¹. The shank N of the transverse handle bar O fits inside the tube
forming the detachable frame A¹ and is adjustable therewith, being locked by any
suitable device. Q designates the stayrod formed in two parts adjustable with
suspect to each other, to lengthen or shorten the rod, by the right and left handed
nut q. The free ends of the rod are bent at right angles to the length of the bar,
'which ends drop into holes in suitable brackets R and R¹ fixed respectively to the
Beat support J or main frames A and to the detachable frame A¹. L', L¹, designate
the vertical spade handles for the rear rider, one of which is free to turn in its
socket, and is provided with a pinion in gear with an extension M¹ of the rack
-steering rod M, which extension is attached to the rod M by a socket joint m, so
that it can readily be attached and detached. S, S, designate the detachable
brackets carrying the handles L' L', which are provided with shanks s¹, s¹, which
fit in sockets 8, 8, fixed to, or forming part of, the main frame A, suitable set
Screws 8, 8², being provided to lock them in position.

page_text: Those parts to which no reference has been made are of the usual type and
present no novel features.
It will be seen that a machine constructed as herein before described may be
converted into either a single or double tricycle. In its double form the steering
of the machine may be controlled either by the front, or back rider, or by both in
combination. The rear rider has the choice of either a transverse handle bar, or
the usual vertical spade handles, and either may be detached in case they are not
required. In converting the double machine into a single," the detachable is
removed complete in itself.
46
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is;
First. A convertible tandem tricycle constructed substantially, and specifically,
as herein before described, and shown in the accompanying drawings.
Second. In a convertible central driving tandem tricycle, the construction and
arrangement of the parts necessary for the second rider, so that they may be
removed in one complete frame without interfering with the adjustment of any
other part of the tricycle, substantially as herein before described and shown.
Third. In a central driving tricycle for two riders, whose seats are placed
tandemwise, the combination of the detachable frame A' carrying the taper
shank a¹, the main frame A carrying the taper socket a, the set screw a³, and
the adjustable stay rod Q, all combined, arranged, and operating as, and for the
purpose, set forth.
Fourth. In a central driving tricycle for two riders, whose seats are placed
tandemwise, the combination of the detachable frame A¹, the vertical spade
handles L, L, the detachable transverse handle bar O, the detachable sockets S S,
carrying the vertical spade handles L, L¹, and the extension M₁ of the rack
steering rod M all combined, arranged, and operating, as and for the purpose
set forth.
Dated this 16th day of August 1886
ROBT. ED. PHILLIPS, M.I.M.E.,
Agent for the Applicant.