Improvements in Driving Mechanism for such Velocipedes as are Driven by Muscular Effort.
Year: 1899

page_text: Date of Application, 26th June, 1899
Complete Specification Left. 26th Mar. 1900-Accepted. 26th May. 1900
PROVISIONAL SPECIFICATION.
Improvements in Driving Mechanism for such Velocipedes as are
Driven by Muscular Effort.
I, Robert FredERICK HUGHES, of 16, Westmoreland Street, Marylebone, in
the County of London, Inventor, do hereby declare the nature of this invention
to be as follows:-
The invention relates to the application of the driving power of the legs to
velocipedes, and is based on principles which are axiomatic to any person of
ordinary intelligence, but which have met with little or no recognition among
cycle builders, or in books on cycle mechanics. It is therefore necessary that
I should briefly state these principles before describing the combination I have
invented to give effect to them.
I
It is a matter of common experience that muscular_effort, even when the point
of application thereof is not moved, causes fatigue. It follows that much of the
muscular effort applied to the at present almost universal crank driving
mechanism causes fatigue, without helping in the propulsion, since only that
component of the effort that is at right angles to the crank in any given position
of the latter is effective. A similar loss occurs when the leg is used to drive a
crank through the intervention of a lever and link, even when the foot applies
all its force tangentially to the pedal path; since the link is sometimes parallel
to and at other times perpendicular to the crank. It is, however, very com-
monly asserted that there is little or no loss entailed by the use of the ordinary
crank movement, inasmuch as by correct pedalling the muscular effort can be
exerted perpendicularly to the crank in nearly all positions of the latter.
need only point out that when the crank is vertical any such effort is exerted
in a tangential direction round the hip joint as centre, and is exerted at a con-
siderable distance from that centre, especially near the lowest point of the
stroke. Experience teaches us that effort exerted tangentially by an extended
limb is very fatiguing; and a moment's consideration will show how futile it
is to drive at this part of the stroke, when the energy might be reserved for use
to much better advantage in downward strokes. Again, it is matter of common
experience that fatigue supervenes when the legs are rapidly moved, even though
no external work is done. It is therefore important that the legs should be
quiescent whenever no driving is required, and further that full effect should
be given to each movement of the legs when they are in use. The free wheel
system secures the first point. The long crank and high gear system substitutes
full strokes for small ones of greater frequency, and so saves energy by avoiding
unnecessary reversals and variations of speed and pressure. In this connection
it should be remembered that a leg weighs about 30 pounds. My present
invention combines the advantages of the free wheel system with those of the full
stroke high gear system, while avoiding the losses the crank, or a short lever,
imposes when driven by the leg. Each stroke of the foot is of full length, is
substantially radial with reference to the hip joint, and is substantially per-
pendicular to the lever it actuates throughout the stroke: The cord, chain, wire,

page_text: or equivalent strong flexible connection capable of bending in at least two
planes mutually at right angles (hereinafter referred to as the cord) which
alternately takes the pull of the levers, is pulled by each of them substantially
at right angles throughout the lever's stroke; and runs on the circumferences of
2 clutch-driving pulleys (guided by an intermediate third pulley) which alter-
nately engage with the driving spindle from which the back wheel hub of the
bicycle can be actuated, by sprockets and a pitch chain, or by any of the trans-
missions now in use between the crank spindle and driving wheel hub. The
result is that the power of the leg is exerted at its best and fullest stroke, and
is transmitted with but little loss to the hub of the driving wheel.
The principles enunciated are carried into effect as follows:-The main spindle
is held in suitable bearings below the saddle, and carries, besides the vertical
sprocket wheel (supposing chain transmission is used) 2 wheels parallel to the
sprocket wheel, one on each side of the central plane of the machine. These
are the clutch pulleys before mentioned. During the down stroke of the left
and the up stroke of the right leg, the clutch pulley on the left side drives,
while that on the right side runs idle in the opposite direction; and vice versa
during the down stroke of the right leg. The clutch pulleys are actuated by
the cord, which runs from say midway on the right lever to the front of the
right clutch pulley, whose circumference it follows for a sufficient distance, when
it turns towards the left side on the circumference of a loose pulley, round
which it takes 1 turns, and which it then leaves for the circumference of the
left clutch pulley, which, finally, it leaves to reach its attachment to the left lever.
The loose pulley revolves in a plane perpendicular to the parallel planes in
which the clutch pulleys revolve, and its diameter is equal to the distance
between the clutch pulleys, so that the cord, in passing from clutch pulley to loose
pulley, and vice versa, forms a common tangent to circles mutually at right
angles. The cord should be fastened to the loose pulley at the middle point of
the cord to ensure equality and symmetry of the strokes, and the cord may be
caused to take a helical position on the loose pulley to avoid wear and friction
between the portions of the cord which lie side by side on the circumference.
The cord has so far been described as single, but, provided sufficient cord is
allowed to unwind from the loose pulley at each stroke, it is preferable to have
a right and a left cord, both attached to the loose pulley, instead of one cord
running the whole distance.
The lengths of levers and the length of the stroke as well as the gear will vary
according to taste and circumstances, and the length and power of the pull upon
the cord can be made adjustable by shifting the point of attachment of the
cord along the lever. I shall give a numerical example to show a suitable
arrangement for a strong rider.
The levers 26 inches long and pivotted on or near the rear wheel axle. The
cord fastened at about 12 inches from the free forward ends, giving, with a
20 inch stroke of the foot, a little over 10 inches of cord unwound from the
clutch pulley, which might be of 10 inch circumference, and drive a sprocket
wheel of 16 teeth geared to 7 on the back wheel hub. This would give
2 turns of the back wheel for each stroke, equalling a gear of 128, supposing
the back wheel to be 28 inches in diameter. Yet the sprocket wheels and chain
are small enough to be easily enclosed in a gear case, or otherwise protected,
and are moreover in a much cleaner situation than that they usually occupy,
and the gear would be easy to drive, because very little instead of about
50 per cent. of the power applied is wasted.
Dated this 26th day of June 1899

page_text: Improvements in Driving Mechanism for such Velocipedes as are
Driven by Muscular Effort.
I, ROBERT FREDERICK HUGHES, of 16, Westmoreland Street, Marylebone, in
the County of London, Inventor, 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 principles on which my invention is based are sufficiently set out in my
Provisional Specification. The drawings herewith show how, in the case of a
bicycle gear, effect is given to the principles there enunciated.
9
to
11
a is the back wheel, which is driven by the chain b and sprocket wheels c
and in the usual way, except that the driving sprocket wheel is at the top of
the diagonal tube of the frame, instead of at the bottom. The sprocket wheel c
moves with the centre portion of the ratchet pulleys e e¹, and ff are cords, bands,
or chains, capable of bending round the pulleys e and e¹, and also round the
loose pulley g, to the circumference of which the upper end of each of them is
fastened, a sufficient length being first wound on the circumference of
allow of the full stroke of the corresponding lever. (I prefer to have f and f¹
separate--not one cord free upon or fastened at its centre to g). The lower ends
off and fare made fast behind the footplates of the pedal levers hh, which
The action is as follows;-
are pivotted at or behind the back wheel axle.
When the lever his depressed some of the cord f is unwound from g, turning it
and the pulley e, and so driving the bicycle, and winding up a corresponding
portion of f, and raising h. The rim of the pulley e¹ revolves backward with fi
without sensibly checking the central portion of the pulley. In like manner
the downstroke of the lever drives the bicycle, and raises h. The pulley g
can have grooves or guides to prevent the cords f f interfering with one another.
When expedient the cords, bands, or chains ffi may interlock or mesh with
Any other of the known means of
the circumferences over which they pass.
transmitting the' rotation of the crank axle to the back wheel hub may be sub-
stituted for the chain b and sprocket wheels c and d, and clutches may be used
instead of ratchets in e and e¹. If the bracket for the ratchet wheels ee¹ is
placed at the corner of the frame (which I recommend) its form and attachments,
will be very similar to those of the bracket now in use, except that a socket
should be provided for the L pin or other saddle support, and the axle of g may
In place of the
conveniently be supported by an offshoot from the bracket.
bracket usually found at the lower end of the diagonal, a pair of stops ii, to
check the levers at the bottom of their swing, may be fitted. I am aware that
side levers, cords, clutch-pulleys, and sprocket wheels and chain have previously
been combined in suggested driving mechanisms for bicycles, but I believe all
experiments in that direction have been abandoned. My invention consists in
the novel provision for ensuring full length and full power to the stroke when
propulsion is necessary; combined with the provision for resting the legs when
it is not. The full length and power of the stroke arise partly from the length
and disposition of the levers in relation to the legs of the cyclist-(the points
to be aimed at here are full length of stroke and maximum leverage at every
part of it) and partly from the fact that the increased efficiency of the stroke is
5 taken into account in fixing the amount of gearing up. This should always be
done, and the result is that there is a proper resistance throughout the stroke,
which means that the legs (together weighing about twice as much as the
bicycle) are not required to move at an uneconomical velocity.

page_text: 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:
1. The full-stroke, free-wheel, high-gear driving mechanism for velocipedes
constructed adapted and arranged to operate substantially as hereinbefore
described and shown.
2. In connection with a velocipede driving gear a bracket adapted to form the
junction between the upper end of the diagonal and the other members meeting
at the upper angle of the frame.
3. In a bracket as described in Claim 2 a clamping tube or socket to hold the
L pin.
Dated this 26th day of March 1900