Improvements in the Driving Mechanism of Cycles and like Vehicles.
Year: 1898

page_text: Date of Application, 7th Dec., 1898
Complete Specification Left, 6th Feb., 1899-Accepted, 11th Mar., 1899
PROVISIONAL SPECIFICATION.
Improvements in the Driving Mechanism of Cycles and like
Vehicles.
I, JACOBUS GERARDUS DE GROOT, of 32, Schoolstraat, Utrecht, in the Province of
Utrecht, Netherlands, Gentleman, do hereby declare the nature of this invention
to be as follows:-
This invention relates to certain improvements in the driving mechanism of
cycles and the like, the object being to better utilise the power applied on the
cranks, and by so doing to attain a greater speed with less exertion of power.
The invention relates to what is known as the chainless method of driving and
has therefore the advantages attained by doing away with the chain as an inter-
mediary between driving axle and the axle of the propelled wheel or wheels of
the cycle or the like.
a
According to my invention when applied to a bicycle I arrange
link loosely on the axle of the back wheel, which link has the same length as
the pedal crank, and I connect both by means of a rod forming a driving rod.
The axle of the back wheel also carries a gear wheel or pinion fixed on same, and
a second gear wheel of larger size is fixed on the end of a pin on the connecting
rod to which the link is loosely connected. This latter wheel engages the first
wheel as the link rotates about the axle by the movement of the driving rod
and by so doing drives the back wheel. The proportion between the number of
teeth of the two gear wheels determines the so called gearing of the bicycle.
For the purpose of balancing the parts I pivot a beam to a suitable point on
the frame, preferably over the mechanism above described, and connect one end
of the beam by means of a rod to the end of the link on the back wheel axle,
and the other end to the strap of an eccentric arranged on the crank axle, or an
equivalent device may be employed. The eccentric when employed is so fixed
on the crank axle that its centre lies vertically above the crank axle in the lowest
position of the crank, so that it rises and forces the beam end upward in the
downward movement of the crank, and by so doing assist in carrying the wheel
on the link at the back wheel downward and vice versa.
Dated the 7th day of December 1898.
PHILIP M. JUSTICE,
Chartered Patent Agent, London, for the Applicant.
PHILIP M. JUSTICE,
Chartered Patent Agent, London, for the Applicant.
CUAIPLETE SPECIFICATION.
Improvements in the Driving Mechanism of Cycles and like
Vehicles.
I, JACOBUS GERARDUS DE GROOT, of 32, Schoolstraat, Utrecht, in the Province of
Utrecht, Netherlands, Gentleman, do hereby declare the nature of this invention
Pain Q.11

page_text: and in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement;-
This invention relates to certain improvements in the driving mechanism of
cycles and the like, the object being to better utilise the power applied on the
cranks, and by so doing to attain a greater speed with less exertion of power.
The invention relates to what is known as the chainless method of driving and
has therefore the advantages attained by doing away with the chain as an inter-
mediary between driving axle and the axle of the propelled wheel or wheels of
the cycle or the like.
According to one form of my invention when applied to a bicycle I arrange a
link loosely on the axle of the back wheel, which link has the same length as
the pedal crank and I connect both by means of a rod forming a driving rod.
The axle of the back wheel also carries a gear wheel or pinion fixed on same, and
a second gear wheel of larger size is fixed on the end of a pin on the connecting
rod to which the link is loosely connected. This latter wheel engages the first
wheel as the link rotates about the axle by the movement of the driving rod,
and by so doing drives the back wheel. The proportion between the number of
teeth of the two gear wheels determines the so called gearing of the bicycle.
For the purpose of balancing the parts I employ a suitable device connected to
the link to relieve the friction on same and on the back wheel axle. Driving
mechanisms of this kind are already known, but have so far been practically
utilized only to a limited extent, owing to the friction which has to be overcome.
The chief object of the present invention has been to reduce this friction to a
minimum.
I have shewn in the accompanying drawings the preferred form in which I
carry out my invention.
In these drawings:
Figure 1 is a side elevation, of sufficient of the parts of a bicycle to illustrate
the invention and
Figure 2 is a plan of same.
Upon the axle f of the back wheel is keyed or screwed a toothed wheel w,
adapted to gear with a wheel w¹ of equal or larger size. Upon each side of these
two toothed wheels a loose link e is arranged, (or one link only might be employed)
which is connected with the pedal crank b of the crank axle a, by means of a
driving rod d. In the form shewn this rod constitutes a part of a rigid angular
frame made up of the parts ds and the latter acting to stiffen the whole.
The arm or parts of this frame is pivotally connected to a link h, pivoted in
turn to a fixed point r of the frame. The rod d may be so arranged as to have
its working or pivoting point at the end of the pedal crank or at a point lying
nearer to the crank shaft a, as shown in the drawing. I prefer the latter arrange-
ment, as otherwise the dimensions of the toothed wheels w, w¹, of the frame dst,
and of the links e and h would become too large. These links e and h should be
of the same length as the pedal crank bor of the distance between its centre and
the pivoted point of rod d so that the motion of the parts becomes a uniform one.
At the apex of the angular frame or near the same the rod d is provided with a
pin pon which the wheel w¹ is rigidly fixed and on which the links ee are free
to turn.
The size of the angle formed by the parts d and s is dependent upon the position
of the point r on the cycle frame relatively to the back wheel axle f. The rigid
angular frame as will be seen moves with the pedal crank b up and down, while
the apex of same and the end of the arm or part s moves around the fixed
points and r, respectively the other end of rod d moving around the fixed point a.
By this construction an even distribution of the power is obtained, the crank e
and the axle particularly being relieved and the friction on same diminished..
As regards the ratio between the number of teeth of the wheels wo and w¹, it may
be pointed out, that it will increase as the wheel is enlarged or as the wheel w
is reduced in size.

page_text: For applying this mechanism to cycles having more than one seat such as
tandems, and the like, all that is necessary is to extend the rod d to the other
pedal cranks, while it may also be easily adapted to tricycles and other similar
vehicles, the arrangement and construction of the parts differing necessarily
with the machine to which it is to be applied.
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. A driving mechanism for cycles and like vehicles consisting of a toothed wheel
carried by a loose link or links and capable of moving around and driving a second
toothed wheel on the back wheel axle, the first wheel being fixed to and carried by
an angular frame one part of which is pivoted to the pedal crank and another
part to a link pivoted to the frame of the cycle or vehicle and adapted to rotate
around its pivotal point substantially as described.
2. The improved driving mechanism for cycles and like vehicles constructed
substantially as described and illustrated.
Dated the 6th day of February 1899.
PHILIP M. JUSTICE,
Chartered Patent Agent, London, for the Applicant.