Improvements in the Driving Mechanism of Bicycles, Tricycles, and other Velocipedes.
Year: 1891

page_text: Date of Application, 16th Apr., 1891
Complete Specification Left, 9th Jan., 1892-Accepted, 20th Feb., 1892
PROVISIONAL SPECIFICATION.
Improvements in the Driving Mechanism of Bicycles, Tricycles, and
other Velocipedes.
I ALBERT EDWARD FISHER CHATTAWAY of No. 117 Princess Road Birming-
ham in the County of Warwick Commercial Traveller do hereby declare the nature
of this invention to be as follows:-
:―
My invention has reference to such bicycles tricycles and other velocipedes as
have chain gearing and consists of the construction and arrangement of parts
hereinafter described of the driving mechanism by the use of which the rider can
when ascending a hill or under other circumstances drive the velocipede with greater
than the normal power but at sacrifice of speed.
My invention is especially suited for bicycles of the kind known as safety bicycles
and I will describe it in connection with a safety bicycle.
The chain wheel over which the chain driving the back wheel passes turns on a
fixed ring through which the pedal or crank axle passes the interior of the said ring
being of much larger diameter than the said axle. The chain wheel works on the
said ring with an anti-friction ball bearing. The chain wheel has the ordinary
teeth on the periphery. Que side of the said chain wheel is recessed or hollowed
and teeth are formed on the interior cylindrical face thus forming a hollow toothed
wheel.
The crank axle carries a small toothed wheel or pinion and also at a short distance
from the said pinion a cross arm of nearly the same length as the internal diameter
of the chain wheel. The bearing in which the axle works is situated in a horizontal
slot in a block fixed to the framing of the bicycle and is capable of sliding in the
said slot and when at either end of the said slot is capable of being temporarily
fixed in position by a projection on its underside being made to engage in a short
cross slot.
This temporary fixing of the axle bearing is effected in the manner
hereinafter explained by a lateral motion of the bearing.
The bearing of the axle is operated by a lever worked by the hand of the rider.
By the backward and forward motion of the said hand lever the axle bearing is
made to slide to one or other end of the slot and by a slight cross motion the said
bearing is temporarily fixed by the projection and short cross slot herein before
referred to.
The action of the parts described is as follows. When the position of the hand
lever is such that the pedal or crank axle is concentric with the chain wheel and
the said axle is made to perform the slight lateral motion which engages the projec-
tion hereinbefore referred to in the end cross slot the bicycle travels at its normal
speed the cross arm bearing by each of its ends against sings on the chain wheel
and thus communicating the motion of the pedal axle directly to the said chain
wheel. When the rider desires to drive with additional power as on ascending a
hill he changes the position of the hand level so as to disengage the cross arm from
the chain wheel and bring the crank axle eccentric to the chain wheel. By the
lateral motion of the hand lever the bearing of the axle is temporarily fixed in
that position and the small toothed wheel or pinion on the axle at the same time
engaged with the hollow toothed wheel of the chain wheel. The chain wheel is
now driven through the said pinion and hollow toothed wheel the chain wheel
rotating only once to several rotations of the axle. The power of the rider is thus
increased the speed of the bicycle being proportionately reduced. The extent to
which the power is multiplied is determined by the ratio of the diameters of the
pinion and hollow toothed wheel.
When the hand lever is not moved in either direction to the full extent the axle

page_text: is disconnected from the chain wheel and the bicycle travels as in going down hill
without the rotation of the pedal axle.
Thus by moving the hand lever to its full extent and then giving it a slight
lateral motion the bicycle may be made to travel either at its normal speed
or at a reduced speed and greater power or by bringing the hand lever into
its middle position the pedal axle may be disconnected from the chain wheel.
The application of my invention to other kinds of bicycles and to tricycles and
other velocipedes differs in no essential respect from its application to a safety
bicycle as hereinbefore explained.
W. T. WHITEMAN,
Agent for the Applicant.
COMPLETE SPECIFICATION.
Improvements in the Driving Mechanism of Bicycles, Tricycles, and
other Velocipedes.
1, ALBERT EDWARD FISHER CHATTAWAY, of No. 117 Princess Road,
Birmingham, in the County of Warwick, Commercial Traveller do hereby
declare the nature of my invention and in what manner the same is to be
performed to be particularly described and ascertained in and by the following
statement:-
My invention has reference to such bicycles, tricycles and other velocipedes as
have chain gearing and consists of the construction and arrangement of parts herein-
after described of the driving mechanism; by the use of which the rider can when
ascending a hill or under other circumstances drive the velocipede with greater than
the normal power but at sacrifice of speed.
My invention is especially suited for bicycles of the kind known as safety
bicycles and I will describe it in connection with a safety bicycle.
The chain wheel over which the chain driving the back wheel passes turns on a
fixed ring through which the pedal or crank axle passes, the interior of the said
ring being of much larger diameter than the said axle. The chain wheel works on
the said ring with an antifriction ball bearing. The chain wheel has the ordinary
teeth on the periphery. One side of the said chain wheel is recessed or hollowed
and teeth are formed on the interior cylindrical face thus forming a hollow toothed
wheel.
The crank axle carries a small toothed wheel or pinion and also at a short distance
from the said pinion a cross arm (or disc) of nearly the same length as the internal
diameter of the chain wheel. The bearing in which the axle works is situated in
a horizontal slot in a block or base plate fixed to the framing of the bicycle and
is capable of sliding in the said slot and when at one end of the said slot is capable
of being temporarily fixed in position by a projection on its underside being made
to engage in a short cross slot. This temporary fixing of the axle bearing is
effected in the manner hereinafter explained by a lateral motion of the bearing.
The bearing of the axle is operated by a lever worked by the hand of the rider.
By the backward and forward motion of the said hand lever the axle bearing is
made to slide to one or other end of the slot and by a slight cross motion the said
bearing is temporarily fixed by the projection and short cross slot herein before
referred to.
By the motions described of the bearing of the crank axle the latter cau either
be made to directly drive the chain wheel at the ordinary speed, or drive the chain
wheel at a reduced speed with additional power at the will of the driver as herein-
after particularly described and illustrated in the accompanying drawings.
1
Figure represents in front elevation and Figure 2 in vertical section, taken
through the chain wheel, the driving mechanism of a safety bicycle, constructed
according to my invention, the parts of the said mechanism being represented in

page_text: Figures 1 and 2 in the positions which they respectively occupy when the bicycle
is to be driven at the normal speed; that is, directly froin the crank shaft:
Figure 3 represents in section the chain wheel and supporting ring taken in a plane
at right angles to that in which the section of Figure 2 is taken, the said Figure 3
exhibiting the ball bearing arrangement of the said chain wheel; Figure 4
represents in plan the base plate supporting the bearing of the crank shaft.
Figures 5 and 6 represent respectively the same views as Figures 1 and 2 with
the parts of the driving mechanism in the positions which they respectively occupy
when the bicycle is to be driven at a slow speed with increased power for hill
climbing; that is, when the chain wheel is driven from the crank shaft through the
small toothed wheel or pinion on the said crank shaft gearing with the internal
toothed wheel of the said chain wheel; Figure 7 represents in end elevation (a
portion in section) the parts in the same positions as in Figures 5 and 6.
The saine letters of reference indicate the same parts in the several figures of the
drawings.
i
r
r
, are the bars of the diamond frame of the bicycle passing respectively to the
steering post and seat post. Between the bottom ends of the said bars is the
horizontal base plate supporting the bearing d in which the crank shaft e turns:
are the cranks on the said shaft. The said bearing d (and the crank shaft
supported in it) is capable of sliding in the base plate in directions at right angles
The connection of the
to one another for the purposes hereinafter described.
compound sliding bearing d with the base plate is effected by means of the boss/
on the underside of the said bearing engaging in the longitudinal and cross slots
and in the said base plate, the said boss being retained in the slot by means of
the washer plate on the underside of the base plate secured to the said boss by
the screw pink. The friction between the sliding bearing and washer plate and
the fixed base plate is reduced by the ball bearing arrangement represented.
Keyed on the crank shaft is a toothed wheel or pinion which by the
longitudinal sliding motion of the bearing d and crank shaft e can be geared with
the internal toothed wheel m of the hollow chain wheel a as represented in
Figures 5, 6 and 7: or ungeared from the said internal toothed wheel as
represented in Figure 2. The chain wheel n rotates on the bearing ring p
attached to the bar of the diamond frame, the friction between the said chain
wheel and bearing ring being reduced by the ball bearing arrangement represented.
The pinion fixed on the crank shaft e carries a disc which when the
driving mechanism is in its normal position closes one side of the hollow
chain wheel 12, the said pinion disc being provided with slots near its
edge which when a cross motion in one direction is given to the crank shaft takes
upon studs n n² on the outer edge of the chain wheel n (see Figures 2, 6 and 7)
and thereby locks the crank shaft with the said chain wheel. By a cross sliding
motion of the crank shaft in an opposite direction to that described, the pinion
disc can be unlocked from the chain wheel n as represented in Figures 6 and 7
for the purpose of permitting of the longitudinal motion of the pinion / necessary
to gear it with the internal toothed wheel m of the chain wheel n.
bearing and parts carried by it, are moved in the cross directions described for
locking the pinion disc to and unlocking it from the chain wheel n, the boss fon
the said bearing works in the cross slot in the base plate e; and when the
bearing d is moved in a longitudinal direction, or in a direction at right angles to
that described, for gearing the pinion with or ungearing it from the internal toothed
wheel of the chain wheel, the boss works in the longitudinal slot g in the base
plate a.
When the
The compound movement described of the bearing d is effected by the motion
of the double jointed hand lever q, the handle end of which is situated within
reach of the rider. This hand lever is forked at bottom the fork embracing the
cylindrical periphery of the bearing d. The branches of the fork are also slotted.
the slots working upon the pins or studs r, r on the said bearing. The hand lever

page_text: is capable of motion in directions at right angles to one another for giving the
compound motion to the bearing d in the following manner.
The jointed part of the hand lever carries the sphere q2 an axial hole in which
works upon the fixed rods carried by the framing of the bicycle. When the
hand lever is moved in the direction of the arrows in Figures 2 and 6, the
sphere turns on the rod as an axis and this motion of the hand lever gives
the cross motion to the bearing d necessary to ungear the crank shaft from the
chain wheel, the contrary motion of the said hand lever q, regearing the crank
has at opposite points, pivots t, which
work in the loop of the lever (see
When the hand lever ሃ is
turned in the direction of the arrow in Figure 1 or in the direction of the arrow
in Figure 5, the hand lever turns on the said pivots f, as fulcra. By the move-
ment of the lever
in the direction of the arrow in Figure 1 the bearing dis
moved longitudinally so as to gear the pinion with the internal toothed wheel m
of the chain wheel 'n (as seen in Figure 5) and by the movement of the lever g in
the direction of the arrow in Figure 5 the pinion 7 is disengaged from the internal
toothed wheel as seen in Figure 1.
shaft with the chain wheel. The sphere and 6).
ፃ
"
The action of the parts of the driving mechanism described is as follows. When
the position of the hand lever is such that the pedal or crank shaft is concentric
with the chain wheel and the said crank shaft has been made to perform the
slight lateral motion which engages the boss or projection on its bearing in the cross
sloth, the several parts of the driving mechanism occupy the positions represented
in Figures 1 and 2, and the safety bicycle travels at its normal speed, the disc
being locked by the slots in it taking onto the snugs or pins on the chain wheel
and thus communicating the motion of the pedal shaft directly to the said chain
wheel. When the rider desires to drive with additional power as on ascending a
hill, he changes the position of the hand levery so as, first, to disengage the disc
from the chain wheel a and afterwards to bring the crank axle or shaft, eccentric
to the chain wheel as represented in Figures 5, 6 and 7. This is effected by first
moving the hand lever 7, in the direction of the arrow in Figure 6, so as to bring
the boss into the slot and then moving the hand lever, at right angles or in
the direction of the arrow in Figure 1, the boss during the last described motion
moving in the longitudinal slot. In Figure 7 the position of the disc after it has
been unlocked from and carried by the crank shaft away from the chain wheel is
indicated in dotted lines. By these motions of the hand lever the small toothed
wheel or pinion on the crank shaft is engaged with the hollow toothed wheel m of
the chain wheel n. The chain wheel is now driven through the said pinion and
hollow toothed wheel, the chain wheel rotating only once to several rotations of the
crank shaft. The power of the rider is thus increased, the speed of the bicycle
being proportionately reduced. The extent to which the power is multiplied is
determined by the ratio of the diameters of the pinion and hollow toothed wheel.
When the hand lever is only moved in the direction necessary to unlock the
pinion dise from the chain wheel, the crank axle is disconnected from the said
chain wheel and the bicycle travels, as in going down hill, without the rotation of
the pedal shaft.
Thus, by moving the hand lever 7 in the proper directions the bicycle may be
made to travel either at its normal speed or at a reduced speed and greater power;
or the pedal axis disconnected from the chain wheel.
The application of my invention to other kinds of bicycles and to tricycles and
other veldeipeles differs in no essential respect from its application to a safety
Bicycle as hereinbefore explained and illustrated in the accompanying drawings.
Having now particularly described and ascertained the nature of my invention
and the manner in which the same is to he performed I declare that I claim as
my invention:--
The improvements in the driving mechanism of bicycles, tricycles and other
velocipedes hereinbefore described and illustrated in the accompanying drawings,

page_text: whereby the velocipede may be made to travel either at its normal speed or at a
reduced speed and greater power or the pedal shaft disconnected from the chain
wheel; that is to say, making the bearing in which the crank shaft or axle turns
capable of a compound sliding motion and the combination therewith of a hollow
chain wheel having an internal toothed wheel, with which internal toothed wheel
a pinion on the crank shaft can be geared or from which it may be ungeared,
together with the arrangement for locking the crank shaft to and unlocking it from
the chain wheel; the several parts of the driving mechanism being constructed and
combined and operating substantially as described and illustrated.
Dated the Eighth day of January 1892.
ALBERT EDWARD FISHER CHATTAWAY.
ALBERT EDWARD FISHER CHATTAWAY.