Improvements in and relating to Velocipedes.
Year: 1896

page_text: Date of Application, 17th Dec., 1896
Complete Specification Left, 17th Sept., 1897-Accepted, 17th Dec., 1897
PROVISIONAL SPECIFICATION..
Improvements in and relating to Velocipedes.
HENRY STANBRIDGE 136 Wellesley Road Chiswick London W. Engineer. do
hereby declare the nature of this invention to be as follows:-
The object of my invention is to provide a substitute for the chain form of
driving especially with reference to velocipedes with pedals fixed in a frame
between two wheels, whereof the rear wheel is the driven one.
I carry out my invention by attaching to the pedal shaft, on one or both sides,
eccentrics. On the hub of the rear or driving wheel, I form a tooth or toothed
wheel worked by a mangle rack connected by rods to the said eccentrics on the
pedal shaft. The proportions of the tooth wheel and mangle rack and also the
eccentrics are so designed as to vary the speed of the driving wheel. In place of
the mangle rack and tooth wheel I may employ a single rack and tooth wheel
or known drum and chain or band device operating the ratchet wheels fixed on
the hub of the said driving wheel.
Dated this 16th day of December 1896.
HENRY STANBRIDGE.
HENRY STANBRIDGE 136 Wellesley Road Chiswick, London W Engineer 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 or motion transmitting gear of cycles.
Fig. I shows a side elevation of part of the rear driving wheel and part of the
frame tubing and bottom bracket of a bicycle fitted with this gear.
Fig. 2 represents a rear view of the axle and rack & pinion, partly in section,
and on an enlarged scale to Fig I The rack is shewn in half way back position.
A represents the rim of the rear or driving wheel.
B the axis of the said wheel.
C, C1, C2, C3 are "D" or other shaped tubes forming what is known as a
double frame.
D is the bottom bracket.
E&E are eccentric discs attached at right angles to each other on the crank
axle F between the said "D" or other shaped tubes forming the double frame.
G & G are eccentric straps ending in a mangle rack as shewn marked H.
I is a pinion attached to the hub or axle of the wheel, there being also one n
the other side of the said hub, said pinions running inside the mangle rack H..

page_text: J is a swing frame, pivotted on the axle B and carrying two rollers K and K',
a similar arrangement is attached on, the other side of the hub, for purposes as
described hereafter.
L and L are cam ledges projecting on top and lower side of the mangle rack.
M is a disc mounted on the axle B to retain the rack in its place.
Motion communicated to the crank axle Fis transmitted by the eccentric discs E
and E to the mangle racks H which alternately act on the pinions I fastened
on the hub. The eccentric discs (connected by straps G and G¹ to the mangle
racks) being mounted on the crank axle F at right angles to each other, there
will consequently always be one or the other of the mangle racks exerting a
straight pulling action on one or the other of the pinions.
Fig I shews one of the mangle racks at the end of its stroke, the mangle rack
on the other side of the hub is now half way forward being kept in gear with
its pinion by the roller K pressing on top of the cam ledge L. The forward
motion of the mangle rack being continued the pinion I in fig. I being revolved
lifts the mangle rack H shewn in fig. I, it being impossible for the said mangle
rack to be thrust back owing to the eccentric disc E being now on dead centre.
This lifting of the rack, combined with a backward action, as the eccentric E
leaves its dead centre, gradually brings the roller K under the pointed end of the
cam ledge L, and the continuation of the backward movement brings the parts
into the position as illustrated in fig. 2. The inverse of this action takes place
when the backward stroke is completed and similar movement can be observed
at alternate times on the other side of the hub. The driving motion being thus
alternately communicated to either side of the hub.
The said frame J carrying the rollers K and K is free to swing slightly (which
movement may be held in check by suitable springs) to allow of any variations
caused by the rise and fall of the straps G and G¹.
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:
The combination of eccentrics mounted on the crank axle with mangle racks
and pinions to communicate driving motion to the rear wheel of a bicycle.
Dated this 17th day of September 1897.
HENRY STANBRIDGE.