Improvements in Alterable-speed Driving Gears for Bicycles and the like.
Year: 1898

page_text: Date of Application, 26th Mar., 1898
Complete Specification Left. 27th Dec. 1898-Accented 10th Enh
1900
PROVISIONAL SPECIFICATION.
Improvements in Alterable-speed Driving Gears for Bicycles
and the like.
I, JOHN HAYTHORN, of Ivy Cottage, Mansewood, Pollokshaws, in the County of
Renfrew, North Britain, Engineer, do hereby declare the nature of this invention
to be as follows, that is to say:-
My said invention has for its object by improved mechanism applicable in con-
nection with the pedal axle of a bicycle, in a compact and convenient manner, to
provide for easily altering the speed relation between the pedal axle and the axle
of the driven wheel. The improved mehanism may be applied to existing bicycles
or to new ones, the driven wheel receiving the action through a pitch chain and
sprocket wheels, or bevil gearing.
In carrying out the invention according to one modification, the sprocket wheel
is fitted to be capable of rotating on the pedal axle, or in a bearing in a box fixed
thereon; and is made with a ring of internal teeth, with which there gears a
pinion fitted to turn on an eccentric bush made with an eye to turn on a hollow
boss formed in the box concentrically with the bearing of the pedal axle. When
the pinion is in action to give the lower speed its eccentric bush is prevented from
turning by a clamp or other suitable stop connected to a handle or lever in a
convenient position for being adjusted by the rider. Between the pinion and the
pedal arm or cheek on that side there is a plate which by cross slots and pins
transmits rotation uniformly from the crank arm to the pinion, the pinion trans-
mitting it to the sprocket wheel, so as to impart the minimum rate of speed.
When the maximum speed is to be employed, the pinion and its eccentric bush
are set free to turn on the concentric bearing, and the sprocket wheel is locked
to the pedal arm, and the whole rotates as one piece.
The sprocket wheel is made with a rim on its inner side to which is applied a
differential brake strap controlable by a hand lever conveniently accessible to
the rider.
The pinion and internally toothed ring may be transposed, the pinion being
formed or fixed concentrically on the sprocket wheel, and the internally toothed
ring being carried on an eccentric bush. With this arrangement the greater speed
will be given through the internally toothed ring and pinion, and the lesser when
the pedal arm is locked to the sprocket wheel.
Instead of the pinion or internally toothed ring being carried by an eccentric
bush, it may be carried on a bearing on a plate which is adjustable in the box,
so as to put the parts into or out of gear as required.
In another modification the sprocket wheel is on a separate axle or spindle from
the pedal axle; and on each axle there are two toothed wheels, a smaller and a
larger wheel on one axle opposite a larger and a smaller one on the other. A
movable piece within the box carries two pinions arranged so that in one position
of the piece one pinion gears with the larger wheel on the pedal axle and with
the smaller wheel on the sprocket-wheel axle, giving the greater speed. In the

page_text: opposite position of the movable piece the other pinion gears with the smaller
wheel on the pedal axle and with the larger one on the sprocket-wheel axle, giving
the lower speed. The toothed wheels on the axles may be proportioned so as in
all cases to make the sprocket wheel make more revolutions than the pedal axle,
which will allow of the sprocket wheel being made 'comparatively small, a con-
venient and otherwise practically advantageous arrangement. The movable piece
can be shifted to give the different speeds, by means of parts connecting it to a
hand lever conveniently accessible to the rider.
Dated this Twenty fifth dow of 'io
1808
COMPLETE SPECIFICATION.
Improvements in Alterable-speed Driving Gears for Bicycles
and the like.
I, JOHN HAYTHORN, of Ivy Cottage, Mansewood, Pollokshaws, in the County of
Renfrew, North Britain, 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, that is to say:-
-
My said invention has for its object by improved mechanism applicable in con-
nection with the pedal axle of a bicycle, in a compact and convenient manner, to
provide for easily altering the speed relation between the pedal axle and the axle
of the driven wheel. The improved mechanism may be applied to existing bicycles
or to new ones, the driven wheel receiving the action through a pitch chain and
sprocket wheels or bevil gearing.
And in order that my said invention and the manner of performing the same
may be properly understood, I hereunto append four sheets of explanatory drawings
to be hereinafter referred to in describing my improvements.
Figures, 1, 2, 3, and 4, on Sheet, 1, of the accompanying drawings, are respec-
tively, a sectional plan, a vertical section, a section as at right angles to Figure, 2,
and a side elevation of one modification of my improved mechanism. Figures, 5,
and 6, are respectively a sectional plan, and a front elevation of a detail. Figure, 7,
is another view of details partly shown in Figure, 3. Figures, 8, 9, and 10, on
Sheet, 2, are respectively a side elevation, a vertical section, and a sectional side
elevation of a second modification of my improved mechanism. Figures, 11, 12,
and 13, on Sheet, 3, are respectively a vertical section, a horizontal section, and a
sectional side elevation of a third modification of my improved mechanism.
Figure, 14, on Sheet, 4, is a side elevation of a bicycle as made with the modi-
fication of my improved mechanism shown on Sheet, 3, and showing hand gear for
altering the speed. In these drawings the same reference letters and numerals
are used to mark the same or like parts wherever they are repeated.
In carrying out my invention according to the modification shown on Sheet, 1,
of the accompanying drawings the sprocket wheel, A, is fixed by screwed pins, A 1,
to a disk, B, which is fitted to rotate in a bearing, B 1, formed on a box or casing, C,
fixed to the pedal axle bearing bracket, D, or the sprocket wheel may be fitted to
be capable of rotating on the pedal axle, D1. The disk, B, is made with a ring
of internal teeth, B2 (only a few of the teeth being shown in Figure, 3) with
which there gears a pinion, E, fitted to turn on an eccentric bush, F, made with
an eye, F1, to turn on the hollow boss, D, formed in the box, C, concentrically
with the bearing of the pedal axle, 11. When the pinion, E, is in action it gives

page_text: "the lower speed its eccentric bush, F, being then prevented from turning by a
clamp, G, working on an eccentric piece, G 1, moved, by a lever, G2, connected
to a handled rod, G3, fitted with an adjusting spring catch, G4, the rod being
placed in a position convenient for being adjusted by the rider. Between the
pinion, E, and the pedal arm, J, there is a plate, K, (Figures 5, and 6) formed with
cross blind slots or grooves, K 1, and provided with pins, K2, having antifriction
rollers, K 3. These pins with their antifriction rollers work in slots, J1, in the
pedal crank, J, and similar pins, E1, fixed to the pinion, E, work in the
grooves, K1, of the plate, K. With this arrangement uniform rotation is trans-
mitted from the crank, J, to the pinion, E, notwithstanding its eccentric position,
the pinion transmitting it to the sprocket wheel, A, so as to impart the minimum
rate of speed. A slot, K4, is formed in the plate, K, so as to allow of its move-
ment relatively to the axle, D 1. When the maximum speed is to be employed
the clamp or stop, G, is released from the eccentric bush, F, by means of the
handled rod, G3, so that the bush, F, is set free to turn on the concentric bear-
ing, D, and the crank, J, the sprocket wheel, A, and the eccentric bush and pinion
then rotate as one piece. The sprocket wheel, A, may be locked to the crank by
a device such as is shown on Sheet, 2, and hereinafter described, if desired, but
this may not be necessary in practice.
The disk, B, to which the sprocket wheel, A, is fixed, is made with a rim, A2,
on its inner side to which is applied a differential brake strap, L, connected by
links, L1, to a two armed differential lever, L2, mounted on a pin, L3, fixed to
the framing the lever being connected to a rod, L 4, furnished with a spring, L5,
and worked by a hand bellcrank lever, L6, mounted on a pin, L 7, fixed to the
back stay and conveniently accessible to the rider for controlling the brake action.
A guard or covering plate, A3, protects the mechanism but is supposed to be
removed in Figure, 4.
The pinion, E, and internally toothed ring, B2, may be transposed, the pinion
being formed or fixed concentrically on the sprocket wheel, A, and the internally-
toothed ring being carried on an eccentric bush. With this arrangement the
lesser speed will be given through the pinion and internally toothed ring and
the greater when the pedal arm is locked to the sprocket wheel.
According to another modification shown on Sheet; 2, the pinion, E, (or it might
be the internally toothed ring, B2) instead of being carried by an eccentric bush
is carried on a bearing, M, on a plate, M 1, which is made with an open part, M2,
so as to permit the pinion, E, to be put into or out of gear with the internally toothed
ring, B2, as required. To enable the plate, M1, carrying the pinion, E, to be
adjusted it is mounted on a pin, M 3, fixed to the casing, C, another pin, M 4, also
fixed to the casing and working in a slot, M5, in the plate, being provided for
steadying purposes. A pin, N, fixed eccentrically on a disk piece, N 1, carried in
a bearing in the casing, C, works in an upper slot, N2, formed in the plate, M 1,
and when it is desired to shift the plate to put the pinion, E, out of gear the disk
piece is turned to the extent of half a revolution by the handle N 3, so that the
pin, N, in turning raises the plate and places the pinion out of action as required.
When the minimum rate of speed is required the pinion, E, is put into gear with
the internally toothed ring, B2, and the pedal arm, J, transmits motion to the
parts by a plate, K, as in the first modification herein before described. When
the maximum speed is to be employed the pinion, E, is put out of gear by means
of the handle, N3, and the sprocket wheel, A, is locked to the pedal arm, J, by a
locking catch, J2, which is inserted into one of a number of notches, A 2, formed
on the sprocket wheel. The locking catch, J 2, works in a frame, J 3, attached
to the back of the pedal arm, J, and it is actuated by an eccentric, J 4, mounted
in bearings, J5, J6, in the pedal arm, and frame, and worked by a spring
handle, J, having a projecting part, JS, to fit corresponding depressions in the
pedal arm, to lock the handle in the desired position.
In another modification shown on Sheets, 3, and 4, the sprocket wheel, A, is on
a axle or spindle, D2, separate from the pedal axle, D1, and on each axle there

page_text: are two toothed wheels a smaller and a larger wheel, D3, D4, being set on the
pedal axle, D1, opposite a larger and a smaller wheel, D5, D6, on the sprocket
wheel axle, D2. A movable piece, P, working in guides, P 1, formed within a
box or casing, Q, carries two pinions, 17, 18, and the arrangement is such, that
in one position of the piece as shown in Figure, 13, one pinion, DS, gears with the
larger wheel, D4, on the pedal axle, D1, and with the smaller wheel, D6, on
the sprocket wheel axle, 12, thereby giving the greater speed. In the opposite
position of the movable piece, P, the other pinion, 17, gears with the smaller
wheel, D3, on the pedal axle, D1, and with the larger wheel, D5, on the sprocket
wheel axle, D2, thereby giving the lower speed. A "free pedal" can be obtained
by placing the movable piece, P, in a middle position so that neither of the
pinions, D7, D 8, is in gear with the toothed wheels on the axles, 1 1, D2. The
toothed wheels on the axles may be proportioned so as in all cases to make
the sprocket wheel make more revolutions than the pedal axle, which will allow of
the sprocket wheel being made comparatively small, a convenient and otherwise
practically advantageous arrangement. The outer end of the movable piece, P,
has fixed to it a pin engaging in a slotted quadrant piece, S, (Figure, 14) turning
on a pin, S1, fixed on two lower stays, S2, which are added to strengthen the
framing. The quadrant piece, S, is connected by a rod, S3, to a handle, T,
working over a quadrant piece, U, fixed to the framing and provided with
notches, U1, U2, U 3, for a spring locking catch, V, fitted to the handle. The
handle is placed in a position conveniently accessible to the rider, and is shown
with its spring locking catch, V, in the outer notch, U 1, which places the movable
piece in a position to give the greater speed as shown in Figure, 13. When the
handle is placed at the inner notch, U 3, it gives the lower speed, and when placed
at the middle notch, U2, it puts the pinions, 17, 18, out of gear and gives a free
pedal. A brake drum, R, may be may be fitted to the sprocket wheel, A, if desired
and a differential brake applied as in the first modification. If desired, bevil
gearing may be employed instead of sprocket and chain gearing.
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. In alterable-speed gears for bicycles and the like, the combination of
mechanism herein before described with reference to Figures, 1, to 7, of the accom-
panying drawings, the application of the plate, K, being a distinguishing feature.
2. In alterable-speed gears for bicycles and the like, the combination of
mechanism hereinbefore described with reference to Figures 8, 9, and 10, of the
accompanying drawings, the peculiarity being the device for moving the pinion, E,
into or out of gear.
3. In alterable-speed gears for bicycles and the like, the combination of
mechanism hereinbefore described with reference to Figures, 11 to 14, of the
accompanying drawings the peculiarity being the placing of the sprocket wheel on
a spindle separate from the pedal spindle, the spindles being fitted with gearing
for two speeds, and an adjustable piece carrying intermediate pinions for trans-
mitting the action at either speed.
Dated this Twenty-fourth day of December 1898.
EDMUND HUNT,
Applicant's Agent.