Improvements in Bicycles, and in Speed and Power Gear therefor.
Year: 1895

page_text: Date of Application, 3rd Sept., 1895
Complete Specification Left, 2nd June, 1896-Accepted, 4th July. 1896
PROVISIONAL SPECIFICATION.
Improvements in Bicycles, and in Speed and Power Gear therefor.
I, JACOBUS HENDRIKUS OERDER, Clerk to the State Mining Engineer, of
Pretoria, in the South African Republic do hereby declare the nature of this
invention to be as follows:-
:-
"
The object of this invention is to provide a bicycle of the well known "safety
type with a two-speed gearing by which it may be driven with greater speed or
with greater power as may be desired by the rider, the change from one speed to
the other being effected without dismounting.
In the improved bicycle the frame at the lower or pedal shaft socket is double
and consists of two parallel parts in each of which is a ball bearing to carry the
rotary pedal crank shaft which in the space between the said parts of the frame
carries two chain wheels and a clutch adapted to slide along the shaft to engage the
one or other of said chain wheels. On the driving wheel hub are two chain
pinions one on each side and chains gear these pinions respectively with the chain
wheels on the pedal crank shaft which latter chain wheels are mounted loosely upon
the pedal crank shaft and are of different sizes, the one being perhaps equal in
diameter to the pinion with which it is geared, the other being perhaps twice the
diameter of its pinion. The pedal crank shaft is squared in the centre upon which
the clutch slides so that the latter cannot revolve upon the shaft. The clutch has
at each end two teeth the faces of which are parallel and the ends slightly rounded
so that they may easily engage in two of four similar recesses or spaces in the web
or between the spokes of the one or other chain wheel. The clutch is adapted to
be disengaged from one chain wheel before the commencement of its engagement
with the other. The ball bearings of the pedal crank shaft are made in blocks
separate from the frame and secured thereto by screw bolts passing through
elongated slots.
Around the centre of the clutch is housed a loose ring carrying two pins at
opposite ends of a diameter. These pins are engaged respectively by the recessed
or slotted ends of the two arms of a fork forming part of a bell crank lever pivoted
on a lug on the centre of a cross bar connecting the two lateral frame bars afore-
said the other arm of the bell crank engaging in a slot in a lever pivoted below to
the frame and extending up to the upper frame between the steering socket and
saddle pillar socket where it terminates in a handle adapted to be moved back and
forth by the rider in order to change the gearing in action.
There may be fitted laterally to the said upper frame bar two spring holders by
which the lever may be retained at either end of its course with sufficient friction
to avoid accidental displacement.
Dated this 3rd day of September 1895.
HERBERT HADDAN & Co.,
Agents to Applicant.

page_text: I, JACOBUS HENDRIKUS OERDER, Clerk to the State Mining Engineer, of
Pretoria in the South African Republic, 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 :-
The object of this invention is to provide a bicycle of the well known safety
type with a two-speed gearing by which it may be driven with greater speed or
with greater power as may be desired by the rider, the change from one speed to
the other being effected without dismounting.
In the annexed drawing,
Fig. 1 is a side elevation of the part of a bicycle frame which carries the pedal
crank shaft with part of the improved gear applied thereto. Fig. 2 is a plan view
thereof.
Fig. 3 is a view of one of the ball-bearings in section.
Fig. 4 is a detail view of the clutch.
Fig. 5 is a view of the frame of the bicycle.
Figs. 6 to 10 are detail views of parts.
In the improved bicycle the frame a at the lower or pedal shaft socket is double
and consists of two parallel parts 6 in each of which is a ball-bearing c to carry the
rotary pedal crank shaft d which in the space between the said parts of the frame
carries two chain-wheels e, f, and a clutch g, adapted to slide along the shaft to
engage the one or other of said chain-wheels e, f. On the driving wheel hub are
two chain pinions h, i, one on each side, and chains j, k, gear these pinions
respectively with the chain-wheels e, f, on the pedal crank shaft d, which latter
chain-wheels are mounted loosely upon the pedal crank shaft d and are of different
sizes, the one being perhaps equal in diameter to the pinion with which it is geared,
the other being perhaps twice the diameter of its pinion. The pedal crank shaft d
is squared in the centre at l upon which the clutch slides so that the latter cannot
revolve upon the shaft. The clutch has at each end two teeth m, m, the faces of
which are parallel and the ends slightly rounded so that they may easily engage in
two of four similar recesses or spaces ", n, in the web or between the spokes of the
one or other chain-wheel e, f. The clutch is adapted to be disengaged from one
chain-wheel before the commencement of its engagement with the other. The
ball-bearings of the pedal crank shaft are made in blocks separate from the frame
and secured thereto by screw-bolts o passing through elongated slots p.
Around the centre of the clutch is housed a loose ring 9 carrying two pins r at
opposite ends of a diameter. These pins are engaged respectively by the recessed
or slotted ends s of the two arms of a fork forming part of a bell-crank-lever t
pivoted on a lug on the centre of a cross-bar v connecting the two lateral frame
bars b aforesaid, the other arm of the bell-crauk engaging in a slot w in a lever
pivoted below to the frame and extending up to the upper frame bar between the
steering socket and saddle pillar socket, where it terminates in a handle y adapted
to be moved back and forth by the rider in order to change the gearing in action.
There may be fitted laterally to the said upper frame bar two spring holders z
by which the lever may be retained at either end of its course with sufficient
friction to avoid accidental displacement.
In this invention the ball-bearings of the pedal crank shaft are separate from
the frame and are adjustable, while they also lie outside the crank wheels thus
strengthening the construction and giving better bearing to the crank shaft.

page_text: Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
The combination of a bicycle frame having two parallel frame bars b, b, of ball-
bearings c adjustably attached to said frame bars, a pedal crank shaft carried by
said bearings, chain-wheels e, f, loose upon said crank shaft and situated between
the bearings c, a clutch member g between said wheels e, f, and adapted to engage
with either of them, bell-crank-lever t, lever x, and spring catches 2, substantially
as and for the purpose described.
Dated this 2nd day of June 1896.
HERBERT HADDAN & Co.,
18 Buckingham Street, Strand, London, W.C.,.
Agents for the Applicant.