Improvements in the Construction of Cycles or Velocipedes.
Year: 1895

page_text: Date of Application, 13th Aug., 1895-Accepted, 26th Oct., 1895
COMPLETE SPECIFICATION.
Improvements in the Construction of Cycles or Velocipedes.
I, BIRGER LJUNGSTRÖM, Mechanician, of 44 B., Grefgatan, Stockholm, in the
Kingdom of Sweden, 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 present invention relates to a cycle or velocipede, which, owing to its light
construction, is easy to drive by means of treading, as with a bicycle, or other
motive power. The most characteristic features of the invention are the steering
arrangements and the driving mechanism. when the vehicle is to be impelled by a
treading motion. The cycle shewn in the accompanying drawings has two steering
wheels abreast, mounted on stud axles, and connected severally to one of a pair of
steering rods. Either wheel may be actuated by its own steering rod, to produce
sympathetic motion in both, thus forming such an angle to each other as is requisite
to pass a greater or smaller curve without any sliding of one or other of the wheels
over the ground. Steering wheels arranged in the said way are. however, already
known, but in this cycle the steering rods (each fitted with a handle) are connected
together below by transverse rods parallel to each other. In the drawings, the
cycle is represented as arranged for treadle driving by means of treading. The
treadles are, by means of chains or ropes, connected with a rear driving wheel,
the nave or shaft of which is provided with suitable ratchet couplings, upon which
the said chains act. The pulleys attached to the driving wheel shaft, or the
driving wheel nave, and upon which the chains or the ropes, at the oscillations of
the treadles, are alternately wound or unwound, have such a shape, that the moment
of greatest efficiency of the chains will be when the treadle is occupying its middle
position, and their propelling action will decrease as the termination of the stroke
of the treadles is reached.
Fig. 1 represents the cycle viewed from the side ;
Fig. 2 the fore part of the carriage. viewed in plan;
Fig. 3 the lower part of a steering rod, viewed from the side;
Figs. 4 and 5 the junction of the steering rods, viewed from the top in two
different positions;
Fig. 6 the said junction, viewed from the front ;
Fig. 7 the cycle viewed from the top, while steering to the side;
Fig. 8 a modification of the junction of the steering rods and couplings, viewed
from the top;
Figs. 9 and 10 details relating to the said junction.
Figs. 11 and 12 represent the before mentioned chain pulley attached to the
driving wheel shaft, viewed from the side and from the edge;
Figs. 13 and 14 a modification of the said pulley; and Figs. 15, 16, and 17,
another modification of the same.
Fig. 18 is a detail of the driving chain.
The two fore wheels a are the steering wheels, mounted on stud axles a* attached
to the steering rods, and is the driving wheel, mounted loosely on a fixed axle
carried by two diagonal forks projecting rearwards from the back standard a.
a are the steering rods, the lower parts of which a extend forwards (Fig. 4). The
steering rods pass through tubular standards a³, which are connected by transverse
pieces at a, and these, in their turn, are connected to the back standard a by
means of bars a, a, respectively. Thus, the parts a³ to a form the frame. The
steering rods a' are inclined rearwards, and are provided with handles a, which are

page_text: seized by the person sitting on the saddle and treading the machine. The
treadle mechanism consists of a pair of bell-crank levers, to the one arm 63 of
which the driving chain 3 is adjustably attached, while the foot plate is fixed
to the other arm . Between the tubular standards a³ is arranged the front seat,
with the foot rest d. The front seat rests on the springs c'c, which are carried by
the cross pieces a' as of the under training. At the sides, the front seat is carried
by the springs c³, fixed to the tubular standards a³ and cross piece a*.
The above mentioned connection between the two steering rods a', and the pair
of wheels a, is constructed as follows:-
Each steering rod is fitted, at its lower end, to a horizontal plate g, immediately
below the stud axle a*, which projects laterally from the steering rod. These
plates are each provided with a fulcrum pivot g³, and a segment slot g', struck
from a centre beyond the fulcrum pivot g². The plates g are clasped by the bar g³
(Figs. 5 and 9), which is forked at both its ends, and has notches g', at its
extremities, to receive the fulcrum pivot g². This bar carries two antifriction
rollers or pivots g, which enter respectively into the slots gl of the two plates g.
From what has been said, it is evident that the distance between the pivots g of
the two plates 9 will vary on the turning of the steering rods. For instance, the
distance will increase ou the shifting of the parts from the position shewn in Fig. 2,
to the position shewn in Fig. 7. As the distance between the rollers or pivots g
is constant, the varying distances between the pivots 9 are determined by
the form of the segment slots g', their distance increasing as the position of
either plate g
is turned by its steering rod from the normal position. By
the coupling of the plates g together in the manner above described, they are
caused, under the action of either steering rod, simultaneously to swing out
a little from each other, and thereby place the wheels a in backwardly
converging positions; or, in other words, imaginary lines extended from
the axes of their respective stud axles will come to intersect each other in
or near the centre of the curve over which the vehicle is travelling. For obtaining
a better steering, the plates 9 are extended backwards, so as to form arms g,
which are pivotally connected to opposite ends of the transverse bar g³.
points of connection 90 are respectively in line with the straight portion a' of
the steering rods. Instead of the slots g' may be employed guides forming the
curved inner border of the projections g, or the slots may be arranged on the
bar y³, and the roller or pivot go may be fixed to the part g. The latter modi-
fication is shewn in Fig. 8. In this case, the slot, at its ends, approaches to the
pivot Consequently the pivot g² must move outwards, if the pivot g' moves
towards the end of the slot. As to the pivot g' and the notch g', these parts
may evidently be modified in such a manner, that the pivot is fixed to the bar,
and the notch made in the plate.
The
This is
The wheels a tend of themselves to take the positions shewn in Fig. 2.
attained by the spiral spring h, which, at its ends, is connected to the bar by
links, and to the bar 9 by other links h³. The links pass through eyes fixed in
the bars (Fig. 7), and are, beyond the eyes, provided with heads, which, at the
position in Fig. 2, are quite near to the eye, that is to say, the spring is somewhat
stiumed. When the wheels, by the steering rods a¹, are turned to the one or the
The other
other side, the spring is stretched by one of the links and h².
links and 2 slide out a little through the eyes. Instead of employing the
links and the spring h, coiled springs d surrounding the steering rods, and
connected at one end thereto, and at their other end to the tubular standards a
(Fig. 1A), may be employed. When the steering rods are turned sideways for
steening, the springs are strained, and a tendency is given to the wheels to recover
their normal position immediately pressure is taken off the handle of the
steering rods.
With respect to the pulleys upon which the driving chains are alternately wound
and unwound, they have, in cycles existing up to this time, bad the shape of a
cylinder or a spiral. In the first case, the torsion of the chain on the shaft remains

page_text: constant in the latter case, it will increase during the whole stroke of the chain,
that is, while one point of the chain moves from the one extreme position to the
other. In the present case, the pulley has, on the contrary, such a shape, that its
power of transmitting motion is at a maximum when the treadle bar occupies its
middle position. Towards the extreme positions of the treadle, the rapidity with
which the chain is wound upon or off the pulley decreases, in consequence whereof,
the motion becomes more uniform. If the chain at one stroke of the pedal does
not take more than one turn round the pulley, the pulley may take the shape of
an excentric mounted on the shaft or the nave in such a manner that its greatest
radius is perpendicular to the chain when the treadle lever occupies its middle
position, or is near the same. If the chain stroke takes more than one turn round
the disc, the chain may be wound up on a spiral path which approaches the shaft
at its beginning as well as at its end.
Figs. 11 and 12 shew, in side and edge view respectively, a pulley of the first
mentioned kind, while Figs. 13 and 14 shew a pulley of the last mentioned kind.
The chain &, Figs. 11 & 12, acts upon the excentric pulley p, which is mounted
on the shaft of the driving wheel, or the nave of said wheel, in such a manner,
that the drag of the chain on the clutch driver is at a maximum at the middle
position of the treadle, but decreases towards both ends of the pedal stroke. pl is
return chain passing around the pulley p, and connected at its opposite ends to
the pulleys p, attached to, or forming part of, the pulleys p. The opposite ends of
this chain are alternately wound upon the pulleys p³, and the chain thus serves to
return the treadles, when depressed, to their raised position. Figs. 13 and 14 shew
a pulley with a spirally formed chain path commencing at a short distance from
the shaft, and gradually leaving the shaft, and finally again approaching the shaft.
The two ends of the path which are nearest to the shaft correspond to the extreme
positions of the treadle, & the part of the path which is at the greatest distance
from the shaft, to a middle position of the same. It is evident, however, that the
ends of the path situated nearest to the shaft, need not be at quite the saine
distance from the shaft; so, also, the transition from an increasing radius to a
decreasing one, need not be limited to a certain point, the path being permitted to
run concentrically with the shaft on a greater or less part of its length, somewhere
between its ends. The pulley and chain may also be arranged as shewn in Figs. 15
to 18. In this case, the pulley resembles a grooved disc, the bottom of the
groove taking the form of a cam, as at ps, while the periphery pt has a circular form, or
nearly so. Further, the chain & is provided with lateral projections p, which may be
formed by winding a wire around the chain, which wire takes the shape shewn in
Fig. 18, where the chain is seen in cross section. The chain attached to the smallest
radius of p enters between the flanges p', and as it is wound up, bears tightly against
the bottom p, until one end of the lateral projections p' of the chain touches the
periphery of the pulley. The lateral projections on the chain are so situate, that
if the pulley is turned from the position shewn in Fig. 15 in the direction indicated
by the arrow, their inner ends will first touch the pulley at the point q, the chain
being no longer supported by the bottom p³. If the revolution of the pulley
continues, the projections p will be laid on the periphery of the pulley. On
continuing the winding up, so soon as the limit of the lateral projections is reached,
the chain will re-enter the groove of the pulley, & approach its centre, until it
reaches the point q'. The winding up or off amounts to one turn and a half, &
the chain is nearest to the shaft at the starting and finishing of the winding.
Evidently it is indifferent, if the shaft or the nave has the described shape, where
the chain is wound up or off, or if a special disc pulley is arranged for the chain,
as shewn on the drawing.
It is the described shape of the pulley on which the driving chain is alternately
rolled & unrolled, that embodies the principle of action illustrated in Figs. 11 to 17.
The above description has reference mainly to tricycles, but some of the
described arrangements can also be used in bicycles, or in any cycle, viz., the
driving chain pulley Figs. 11 to 18.

page_text: Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. The arrangement of cycle or velocipede as above described with' reference
to Figs. 1 to 7, inclusive.
2. The means described for restoring and maintaining the parallelisin of the
steering wheels, when a straight piece of road is reached.
3. The modifications in the construction of the steering mechanism described
with reference to Figs. 8 to 10, inclusive.
4. The construction of cycle frame above described, consisting of two tubular
standards (through which the steering rods pass), braced together by cross pieces,
to form the front top and bottom bars, extending rearwards therefrom, and braced
together by a hind standard, and two diagonal forks projecting rearwards to
embrace the driving wheel, and form bearings for its axle.
5. The arrangement of seat and footstep in connection with the front part of the
frame, as shewn at Figs. 1 and 2.
6. The application to cycles actuated by treading, of the arrangement of parts
described with reference to Figs. 11, 12, 13, and 14, whereby the driving action of
the chain is modified through the course of the pedal stroke, so that the drag
of the chain on the clutch driver is at a maximum at the middle position of the
treadle, and decreases towards both ends of the pedal stroke.
7. The modified arrangement described with reference to Figs. 15 to 18,
inclusive, for driving cycles and obtaining the like result to that mentioned in
Claim 6.
Dated this 13th day of August 1895.
NEWTON & SON,
Agents for the Applicant.