Improvements in Driving Gear for Velocipedes.
Year: 1898

page_text: PROVISIONAL DI MUITIVATION.
Improvements in Driving Gear for Velocipedes.
I, OLIVER ZELAND, of 17, Kungsholmsgatan, Stockholm, in the Kingdom of
Sweden, Engineer, do hereby declare the nature of this invention to be as
follows:-
For transmitting the power from the pedals to the driving wheels of velocipedes
tooth gearing is frequently used, but a great drawback to the use of this kind of
gearing it, that an undue pressure is thrown on to the bearings on account of
the form of the teeth and because the wheels have a constant tendency to move
away from each other on account of the pressure exerted on the teeth.
The object of the present invention is a construction of gear wheels in which
the pressure on the bearings has been reduced to a minimum.
In the form of transmission constructed in accordance with the present
invention the tooth consists of a cylinder that is attached to the wheel by means
of a long and narrow foot. By this arrangement a large space between the
teeth is obtained whereby it is possible to make the pitch circles intersect. In
making the pitch circles intersect the centres or middle lines of the teeth or
cylinders will lie inside one another at the very moment when the pressure on
these teeth is at its greatest, and the wheels, instead of having a tendency to
move apart, will now have a tendency to approach each other.
If the pitch circles, at the point where the wheels gear, simply touch each
other the said wheels will have a tendency to move apart, just the same as in
ordinary gear wheels.
It may now easily be arranged that the pitch circles should intersect in such
a manner that the wheels have no tendency to move either way, whereby the
bearings will not be subjected to any other pressure beyond that arising from
the mere transmission of the power.
In order to diminish as much as possible the friction the cylindrical teeth may
have a rolling contact.
The above explanation with regard to wheels with cylindrical teeth applies
equally well to wheels with conical teeth. On the crank-axle and the spindle at
right angles thereto are fixed wheels provided with conical teeth.
The teeth are made to roll on spindles and are arranged in such a manner that
a tooth on the one wheel may move freely in the space between two teeth on the
other wheel, the wheels being geared into one another so that the pitch circles
of the cones intersect. The contact between the cones is therefore effected at
points lying inside the centre or middle line of the cones, and there is no longer
any tendency for the wheels to move apart. By judicially arranging the points

page_text: of intersection of the pitch-circles the bearings will only be subjected to the
pressure ensuing from the transmission of power.
Dated this 5th of July 1808
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.
Improvements in Driving Gear for Velocipedes.
I, OLIVER ZELAND, of 17, Kungsholmsgaten, Stockholm, in the Kingdom of
Sweden, 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:-
For transmitting the power from the pedals to the driving wheels of velocipedes
toothed-wheel gearing is frequently used, but a great drawback to the use of
this kind of gearing is, that an undue pressure is thrown on to the bearings on
account of the form of the teeth, and because the wheels have a constant tendency
to move away from each other on account of the pressure exerted on the teeth.
The object of the present invention is a construction of gear wheels in which
the pressure on the bearings is reduced to a minimum.
Referring to the accompanying drawing.
Figure illustrates in principle a form of transmission-gear constructed in
accordance with my invention, z being a tooth consisting of a cylinder attached
to the wheel by means of a long and narrow foot f. By this arrangement a
large space y between the teeth is obtained whereby it is made possible to make
the pitch circles intersect as may be seen from Figure 1, which shows the points
of intersection between the pitch circles of the wheels A and c. In making the
pitch circles intersect, the centres or middle lines of the teeth or cylinders will
lie inside one another at the moment when the pressure on these teeth is at its
greatest and the wheels, instead of having a tendency to move apart, will have a
tendency to approach each other.
If the pitch circles, such as shown in Figure 1 at the place where the wheel B
gears into the wheel c, simply touch each other the wheels B and c will have a
tendency to move apart, just as with ordinary gear wheels. Now it may easily be
so arranged that the pitch circles shall intersect in such a manner that the
wheels shall have no tendency to move either way, whereby the bearings will
not be subjected to any other pressure except that arising from the mere trans-
mission of the power. In order to diminish the friction as much as possible the
cylindrical teeth may have rolling contact such as shown in Figure 1, the said
teeth being provided with rollers h turning on spindles g.
What has been stated above respecting wheels with cylindrical teeth applies
equally well to wheels with conical teeth such as shown in Figure 2. On the
crank-axle b and the spindle d at right angles thereto are respectively fixed
wheels cand e provided with conical teeth h. The teeth may roll on spindles
and are arranged in such a manner that a tooth on the one wheel may move freely
in the space between two teeth on the other wheel the wheels being geared
together so that the pitch circles of the cones intersect.
the cones is therefore effected at points lying inside the centre or middle line of the
The contact between
cones and there is no longer any tendency for the wheels to move apart. By
judiciously arranging the points of intersection of the pitch circles the bearings
will only be subjected to the pressure ensuing from the transmission of power.

page_text: 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―
In driving gear for velocipedes in which the transmission of power is effected
by means of toothed wheels having teeth of cylindrical or conical shape and
mounted on narrow feet; the arrangement that the pitch-lines for the teeth are
made to intersect for the purpose of reducing the pressure on the bearings.
Dated this 11th day of Tal
1000
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.