AN IMPROVEMENT IN BICYCLES
Year: 1883

page_text: LETTERS PATENT to Richard Comings Thompson of Brixton and William
Spence of Surbiton, both in the County of Surrey for an Invention of AN
IMPROVEMENT IN BICYCLES
PROVISIONAL SPECIFICATION left by the said Richard Comings Thompson
and William Spence at the Office of the Commissioners of Patents on the
1st November 1883.
RICHARD COMINGS THOMPSON of Brixton and WILLIAM SPENCE of Surbiton,
both in the County of Surrey "AN IMPROVEMENT IN BICYCLES."
Our Invention relates to what may be termed by analogy an "open fronted "
bicycle that is to say a bicycle in which there is no obstruction to the descent of
the rider in the forward direction so that in the event of the rider being thrown
forwards in consequence of the wheel meeting an obstacle or from any other causo,
he will not be thrown on his face as is usually the case in consequence of his legs
catching against the steering handle.
!
According to our Invention the steering handles occupy the usual position but
instead of being attached to the usual cross bar fixed on to the head of the steering
fork they are attached to prolongations of the lower extremities of the two
branches of the steering fork which are continued beyond the bearings of the
driving wheel in a curved form taking a downward forward and outward and
finally an upward direction the steering handles being fixed to the extremities of
these prolongations. These prolongations take such a direction as to clear the
cranks and pedals, and form no obstruction in dismounting by the pedal, in the
usual way, at the same time they are situated at such a distance laterally from the
steering fork as to admit of the riders legs passing freely between tliem and tho fork
so that should the rider be thrown he would pass clear over the head of the steering
fork and alight on his feet without being entangled in the machine. As a result of
this arrangement the rider has the further advantage of being able to sit morë
directly over his work than it would be safe to do with an ordinary bicycle.
The cranks may or may not be made double arined and have an outside bearing
in the said prolongations and any of the brakes now employed may be provided to
be operated by connections passing down alongside or through said prolongations
and
up the steering fork in any convenient manner
3

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Richard Comings Thompson and William Spence in the Patent Office
on the 1st May 1884.
RICHARD COMINGS THOMPSON of Brixton and WILLIAM SPENCE of Surbiton
both in the County of Surrey "AN IMPROVEMENT IN BICYCLES
"
Our Invention rolates to what may be termed by analogy an "open fronted"
bicycle that is to say a bicycle in which there is no obstruction to the rider's legs
in the forward direction so that in the event of the rider being thrown forwards by
reason of the wheel meeting an obstacle or from any other cause, he will not be
thrown on his face in consequence of his legs catching against the steering handle
as usually happens.
According to our Invention the steering handles occupy the usual position, but
instead of being attached to a cross bar fixed on to the head of the steering fork
the lower extremities of the two branches of the steering fork are continued beyond
the bearings of the driving wheel and bent outwards so as to pass under or beyond
the orbit of the pedals and thence in an upward direction, the steering handles
being fixed to the extremities of these prolongations. Theso prolongations take
such a direction as whilst clearing the cranks and pedals when at full throw, to
form no obstruction in dismounting sideways by the pedal, in the usual way, at
the same time they are situated at such a distance laterally from the steering fork
as to admit of the rider's legs passing freely between them and the fork so that
should the rider be thrown he would pass clear over the head of the steering fork
and alight on his feet without being entangled in the machine. As a result of this
arrangement, the rider has the further advantage of being able to sit more directly
over his work than it would be safe to do with an ordinary bicyclo.
In the accompanying drawings figure 1 represents a front elevation and figuro 2
a sido elevation of our improved bicycle. The same letters of reference indicate
the same parts in both figures.
A A are the handles occupying the same position as when fixed on the ends of
the ordinary cross-bar. C is the steering fork jointed to the back bone B by any
ordinary construction of head, the height of the head being however reduced as
much as possible consistently with the necessary strength of the joint so as to
allow of the horn of the saddle projecting over the top of the head and avoid
liability of any part of the rider's person catching against the head of the fork
when thrown over it.
In
The handles A are fixed to the upper ends of arms D which form extensions of
the arms of the steering fork C said arms D being forged or fixed upon the lower
extremities of the limbs of said fork, and of such shape as to pass (between the driving
wheel and the path described by the driving cranks E) in a downward or forward
direction then outwardly under or beyond the path of the treadles F and finally
upwards to any desired height for the handles A. The cranks and pedals thus
revolve within the bends of these extensions D and quite clear of the same.
the drawing we have shown the part d of the extensions D as passing vertically
downwards and the part das passing across beneath the lowest point of the orbit
of the pedal but we do not limit ourselves to this precise form as the part & may
be inclined forwards and the part d' may pass more or less in front of the said
orbit provided it is low enough to offer no obstruction to the rider's foot whatever
may be the position of the crank at the moment when tho rider is thrown. We
have shown the part d² of the extensions as curved forward to offer no impediment
to dismounting sideways by the pedal in the usual mannor and the upper parts of t
the extensions D are represented as having the same rake as the steering fork, but
d

page_text: it will be obvious that they may be curved or carried more or less forward at ď³
as may be required and may have any desired degree of rake, and the handles A
may either be abreast of the steering head or more or less forward or rearward of
it as desired; the essential feature of the invention being that there is a clear
passage for the rider's legs between the steering handles A and the steering fork
and head. In order to obtain the necessary rigidity of the arms to prevent
vibration in the lateral direction we make them preferably of steel tubing either
thicker at the bends and gradually tapering upwards or of tubing stiffened by being
made at the bend of the cross section shown in figure 3 or by the application ab
that point of a stiffening piece brazed on, as shown in figure 4. or otherwise
In the drawing the arms D are shown as attached to the fork by being formed
in one with the lower part of a divided bearing but they might be made in one
piece with the fork, the bearings being separate and secured to the front or rear
side of the fork. We have also shown the fork as provided with the ordinary form
of head but if preferred a flat head may be used (consisting of two horizontal discs
one on the fork and the other on the backbone connected by a centre bolt and
with antifriction balls between them) thus avoiding the undue raising of the
saddle.
The Invention may also be applied to that class of safety bicycle in which the
driving cranks are not on the driving wheel axle but aro goared therowith and as
the danger of a sido fall is slight the arms may with advantage be brought up
straight (after being bent outwards to clear the cranks) instead of being bent
forwards as at d³ and it will be obvious that in that case the cranks may be mado.
double armed and have an outside bearing in the arms D.
Having described the nature of the said Invention, and the manner of performing
the same, we declare that what we claim as the Invention to be protected by the
horeinbefore in part recited Letters Patent is:
The combination, with the steering fork of a bicycle, of extensions or arms
attached rigidly to the lower extremities of the said fork, or made in one therewith,
passing beyond and clear of the paths described by the cranks and pedals and
rising at either side of the steering fork at such a distance therefrom as to admit
the rider's legs between them and the fork, said arms or extensions having handles
attached to their upper ends, substantially as shown and described for the purpose
specified.
In witness whereof we the said Richard Comings Thompson and William
Spence have hereunto set our hands and seals this first day of May, A.D. 1884.
DIAHAnn CAUTOG
МТАспал17