A New or Improved Driving Gear for Cycles.
Year: 1897

page_text: Date of Application, 3rd May, 1897
Complete Specification Left, 3rd Feb., 1898-Accepted, 3rd May, 1898.
A New or Improved Driving Gear for Cycles.
I, THOMAS GRANT, of 11, St. James's Street, Brighton, in the County of Sussex,
Dealer in Cycles, do hereby declare the nature of this invention to be as
follows:-
This invention relates to driving gear for bicycles tricycles, and the like, and
consists of apparatus by means of which the motion of the bottom bracket spindle
is transmitted to the driving wheel without the use of a chain or chains.
To the bottom bracket spindle, or to the cranks upon the same, are fitted studs,
pins or cams which rotate or rock with the bottom bracket spindle. Upon either
side of the machine are arranged connecting rods, the front ends of which are
attached to one of the pins, studs or cams, while the other end is fixed to a ball
bearing eccentric band which is mounted upon an eccentric sheave, this latter
being either fixed to the hub or axle of the driving wheel or mounted so as to
be capable of rotating upon the hub, axle or a pin which is fixed rigidly to the
frame of the vehicle."
The reciprocation of the connecting rods pulling or thrusting the eccentric
causes it to rotate. When the sheave is fixed to the hub of the wheel, either with
or without gearing, this causes the machine to progress; while when the sheave
rotates upon the hub, axle or pins on the frame, gearing is provided which con-
nects the sheave to the driving wheel hub.
In some cases I pivotally attach hand levers to the frame in such manner that
they may be used as auxiliaries to assist in the propulsion of the machine.
Dated this 3rd day of M 1897
uproved Driving Gear for Cycles.
I, THOMAS GRANT, of 11, St. James's Street, Brighton, in the County of Sussex,
Dealer in Cycles, 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;
This invention relates to driving gear for bicycles, tricycles, and the like, and

page_text: consists of apparatus by means of which the motion of the bottom bracket spindle
is transmitted to the driving wheel without the use of a chain or chains.
To the bottom bracket spindle, or to the cranks upon the same, are fitted studs,
pins, or cams which rotate or rock with the bottom bracket spindle. Upon either
side of the machine are arranged connecting rods, the front ends of which are
attached to one of the pins, studs or cams, while the other end is fixed to a ball
bearing eccentric band, which is mounted upon an eccentric sheave, this latter
being either fixed to the hub or axle of the driving wheel, or mounted so as to
be capable of rotating upon the hub, axle, or a pin which is fixed rigidly to the
frame of the vehicle.
The reciprocation of the connecting rods pulling or thrusting the eccentric
causes it to rotate. When the sheave is fixed to the hub of the wheel, either with
or without gearing, this causes the machine to progress; while when the sheave
rotates upon the hub, axle or pins on the frame, gearing is provided which con-
nects the sheave to the driving wheel hub.
In order that my invention may be fully understood and ascertained I have
appended drawings in which :-
Fig. 1 shews one form of my invention as applied to a rear driving safety bicycle.
Fig. 2 shews a modification of same.
Fig. 3 shews a rod having notches or recesses cut in it for engaging with studs.
Fig. 4 shews another modification of my driving gear, and
Fig. 4 is an enlarged view of part of the connecting rod as used therewith,
shewing notch or slot.
Fig. represents a further modification, and
Fig. 5 is an enlarged view of part of the rod shewing the form of notches or
teeth which I prefer to use.
As my invention is particularly suitable for application to a rear-driving safety
bicycle I will proceed to describe it with reference thereto.
Referring to Fig. 1 A indicates the two connecting rods, which are attached
at one end to a ball bearing eccentric band B mounted upon an eccentric sheave C,
which is fixed to the driving wheel hub; or mounted so as to be capable of rotating
on the hub, axle, or on a pin fixed rigidly to the frame of the machine. In these
latter cases the boss of the sheave is connected by gearing with the hub of the
road wheel.
D indicates the ring which is fixed upon the bottom bracket spindle E, having
pedal cranks d and pedals attached thereto for the feet of the rider. This ring
is provided with rollers, pins or studs so arranged as to engage with the sides
of a square or other rectangular frame which forms part of the connecting rods,
by which means they are thrust backwards and forwards. This backward and for-
ward movement of the connecting rods causes the rotation of the eccentric and the
driving wheel, and consequently the propulsion of the machine.
In Fig. 2 the cam D is shewn as being of nearly elliptical form, and in this
modification the rollers, pins or studs are caused to engage notches d³ formed
in the cam. In this case no end frame is required, the ends of the connecting
rods A being connected to the cam. The other ends of the connecting rods are
attached to a ball bearing eccentric band B, mounted upon the eccentric sheave C,
which is fixed to the driving wheel hub, or mounted so as to be capable of rotating
freely on the hub as before.
It will be seen that when the pedal and crank d are rotated by the foot of
the rider, the rollers, pins or studs are caused alternately to engage the notches
or slots in the cam, thereby imparting a reciprocating motion to the cam, and
consequently alternately pulling and thrusting the connecting rods A. By this
means the eccentric is rotated. which causes the hub of the wheel to revolve, and
this results in the propulsion of the machine.
Fig. 3 shews a modification in which two connecting rods A are joined by a
cross bar a so as to form a rigid frame. Notches or slots e are cut on the inner
edges of the rods, and the pins, rollers or studs d³ are arranged in such manner

page_text: that when rotated, one of them engages one of the notches and pushes the frame
in one direction; when this stud leaves the notch, another enters a notch in the
other rod and thrusts the frame in the other direction. By means of an eccentric
and sheave the reciprocating movement thus produced rotates the hub in a similar
manner to that described with reference to Fig. 1.
Referring to Figs. 4 and 4.
D indicates a ring, which is here shewn as being circular, and is mounted upon
the bottom bracket spindle and indicates rollers, pins or studs attached thereto
for the purpose of engaging at intervals a notch or slot in the rod A. This
rod A is pivotally attached to a supporting link which is pivoted at its upper
end to any suitable part of the frame. The opposite end of the rod A is attached
to the eccentric strap or band B which encircles the eccentric sheave C mounted
on the hub or spindle of the driving wheel. It will thus be seen that when the
pedal crank d is rotated by the foot of the rider pressing on the pedal, the
rollers pins or studs are caused to successively engage the notch or slot d³ in
the rod A. When this occurs the rod is pushed backwards thereby causing the
eccentric strap or baud B to rotate and with it the eccentric sheave C and hub of
the wheel. The rotation of the road wheel and eccentric sheave brings the rod
back to its original position. The rollers, pins, or studs are so arranged that
immediately the eccentric has made a complete revolution the next roller will
engage the notch or slot, and so the operation is again repeated.
In Fig. 5 a somewhat different arrangement is shewn. In this modification
the eccentric sheave C is mounted upon the bottom bracket spindle instead of on
the back wheel hub. It is surrounded by a strap or band B, to which is connected
one end of a rod or bar A, the other end of which is pivotally connected to a
second rod or bar a, one end of which latter is pivoted to a suitable part of the
frame at a¹.
The other end of this rod a is pivotally attached to the rod 1, which latter has
notches formed upon its under side to engage with rollers, pins or studs, fixed
on the ring or wheel D, which is mounted on the driving wheel hub. The opera-
tion of this device is as follows:-The eccentric being rotated by the foot of the
rider pressing on the pedal, attached to the end of the crank d, forces the upper
end of the rod a backwards, and with it the rod F, thus rotating the ring or wheel D
by the teeth engaging the rollers thereon, and consequently rotating the back
wheel, and propelling the machine.
Fig. 5 represents an enlarged view of part of the rod F shewing form of teeth
or notches which I prefer to employ when using the modification shewn in Fig. 5.
If preferred the eccentric and cam or stud wheel may be reversed: the eccentric
being mounted on the bottom bracket spindle, while the cam or stud wheel may
be mounted upon the hub of the wheel.
If preferred hand levers may be attached to any suitable part of the machine
and connected to the cams or rings so as to form an additional means of propulsion.
I would have it understood that I do not confine myself to the particular shape
of the cams or frames, as herein before shewn and described, but they may be of
any contour desired.
In some cases I may attach rollers, pins or studs to the rod to engage slots or
notches in the cam or ring. Or instead of fixing the ring D (Figs. 5 and 5^) on
the back wheel it might equally well be applied to the front wheel of the machine
by reversing the salient angles of the teeth in the bar F.
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 gear for cycles, constructed and operating substantially in the
manner and for the purpose described and shewn.
2. A driving gear for cycles, in which the rotation of the bottom bracket spindle
by means of rollers or the like arranged on the same, moves a frame backward

page_text: and forwards, which reciprocation causes an eccentric sheave fixed or connected
to the road wheel hub to rotate, thus propelling the cycle, substantially as described
-and-shewn.
-
3. A driving gear for cycles in which the rotation of the bottom bracket spindle
by means of rollers or the like, which in their rotation alternately engage notches in a
cam fixed to the connecting rod, cause the latter to reciprocate, and thus rotate an
eccentric sheave fixed or connected to the road wheel hub, the cycle being thereby
propelled, substantially as described and. shewn.
4. A driving gear for cycles substantially as shewn and described with refer-
ence to Fig. 1 of the accompanying drawings.
"
5. A driving gear for cycles, substantially as shewn and described with refer-
ence to Fig. 2 of the accompanying drawings.
Dated this 3rd day of February 1898
WILLIAM J. MUNDEN,
75, Chancery Lane, London, W.C., Agent for the Applicant.