A New or Improved Speed Indicator for Bicycles, Tricycles, and the like.
Year: 1895

page_text: Date of Application, 12th June, 1895
Complete Specification Left, 12th Mar., 1896-Accepted, 18th Apr., 1896
PROVISIONAL SPECIFICATION.
[Communicated from abroad by EDOUARD VEDOVELLI, of 42 Rue Barbet-de-
Jouy, Paris, in the Republic of France.]
A New or Improved Speed Indicator for Bicycles, Tricycles, and
the like.
I, ERNEST OLDENBOURG, of 21, Dowgate Hill, in the City of London,
Merchant, do hereby declare the nature of this invention to be as follows:-
This invention relates to a speed indicator applicable to bicycles, tricycles, and
other similar vehicles, which consists essentially of a cylindrical or other suitably.
shaped tube of glass, preferably closed at both ends by any suitable means such as
by metallic caps for example. In the interior of this tube is placed glycerine or
other liquid which does not completely fill the tube, but the surface of which
stands normally at a certain distance from the upper cap.
If this tube is caused
to rotate rapidly on its axis the liquid is caused to rotate with it, and the molecules
of the liquid are subjected to two forces, the one constant, namely that of gravity,
the other variable, namely the centrifugal force, which tends to cause the liquid to
adhere to the sides of the tube. The effect of the resultant of these two forces is
to depress the surface of the liquid and to give thereto a form more and more
concave as the speed of rotation increases, and it is obvious that all other
conditions being equal the level of the concave surface or meniscus will always be
the same for the same speed.
The glass tube is provided with a graduated scale placed parallel thereto and
may be supported by a suitable bracket or other device secured to the frame of the
vehicle, and it may be adapted to rotate on pivot screws or in any other suitable
bearings therein. On one of the metallic caps of the tube is formed or fixed a
grooved pulley by means of which the rotatory motion is imparted to the tube by
a driving cord from a pulley on the nave of one of the wheels or on the
crank axis.
It will now be understood that the speed of rotation of the tube at any moment
and inferentially the speed of the vehicle from which it receives its rotatory motion
can readily be ascertained by reading off the height of the meniscus, or if preferred
the height of the upper edge of the liquid at the side of the tube with reference to
the scale.
For convenience of reading the speeds the tube and its scale may be placed at
an angle, say about 45°, with the vertical, so that the line of sight of the cyclist
may form perpendicularly, or nearly so, to the graduated scale. The inclination
of the tube and its scale may be varied at pleasure by suitably mounting them
adjustably on the frame of the machine.
I do not confine myself to any particular forms or arrangements of the parts
composing the apparatus as they may be varied without departing from the nature
of the invention.
Dated this 12th day of June 1805

page_text: A New or Improved Speed Indicator for Bicycles, Tricycles, and
the like.
I, ERNEST OLDENBOURG, of 1 Dowgate Hill, in the City of London,
Merchant, 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 a speed indicator applicable to bicycles, tricycles and
other similar vehicles, and is illustrated in the annexed sheet of drawings, in
which
Figure 1 is a sectional elevation of a speed indicator constructed so as to be
readily applied to some part of the framing of a vehicle of the kind above-
mentioned, Figure 2 is a perspective view showing the indicator fixed in position
on such framing, and
Figures 3 and 4 are elevations, taken at right angles to one another, of a pulley
rim which can be readily fixed on one of the wheels of the vehicle, for the purpose
of transmitting motion to the speed indicator.
The speed indicator consists essentially of a cylindrical or other suitably shaped
tube A of glass, preferably closed at both ends by any suitable means, such as by
metallic caps B, C, for example. In the interior of this tube is placed glycerine
or other suitable liquid, which does not completely fill the tube A, but the
surface D of which stands normally at a certain distance from the upper cap B.
When this tube A is caused to rotate rapidly on its axis the liquid is caused to
rotate with it, and the molecules of the liquid are subjected to two forces, the one
constant, namely that of gravity, the other variable, namely the centrifugal force,
which latter tends to cause the liquid to adhere to the sides of the tube. The
effect of the resultant of these two forces is to depress the surface of the liquid, and
to give thereto a form more and more concave as the speed of rotation increases,
and it is obvious that, all other conditions being equal, the level of the concave
surface or meniscus D' will always be the same for the same speed of rotation of
the tube.
The glass tube A is preferably enclosed in a case A' provided with one or more
openings through which the tube A can be seen, and with a graduated scale E
placed parallel to the tube A, and the latter with its case A' may be supported by
a suitable bracket F, or other device, by which it can be secured to some part,
G for example, of the frame of the vehicle and the said tube is adapted to rotate on
pivot screws H, I, or other suitable bearings. On one of the metallic caps of the
tube A, that marked C for example, is formed or fixed a grooved pulley J by
means of which the rotatory motion is imparted to the tube by a driving cord K
from a pulley on the nave or other part of one of the wheels, or on the crank axis
of the vehicle.
It will now be understood that the speed of rotation of the tube at any moment
and, inferentially, the speed of the vehicle from which it receives its rotatory
motion, can readily be ascertained by reading off the height of the meniscus D³,
or if preferred the height of the upper edge of the liquid at the side of the tube,
with reference to the scale E, which latter may be marked to indicate miles or
other distance per hour.
For convenience of reading the speeds the tube A with its scale E may be
secured adjustably on the framing of the vehicle so as to stand at any suitable
angle with the vertical as shown in Figure 2, so that the line of sight of the cyclist
may fall perpendicularly, or nearly so, to the tube and its graduated scale.
In cases where the speed indicator is to be applied to vehicles not already

page_text: provided with a driving pulley on one of its wheels, or on its crank axis, suitable
for communicating rotatory motion to the tube A, the device shown in Figures 3
and 4 will be found convenient, and can be easily applied. It consists of a grooved
pulley rim L which can be secured to the spokes M of one of the wheels of the
vehicle by means of the clamps N which can be tightened up so as clamp the said
spokes between themselves and the pulley rim L by means of the screws P. When
this pulley rim L is thus secured to the wheel in a position concentric to the centre
thereof the driving cord K may be passed round it and motion be thereby
transmitted to the pulley J on the tube A in a manner that will be readily
understood.
I do not confine myself to any particular forms or arrangements of the parts
composing the apparatus, as they may be varied without departing from the nature
of the invention.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, 1 declare that what I
claim is :-
First. The new or improved speed indicator for bicycles, tricycles, and the like,
constructed, arranged and operating substantially as described.
Second. The new or improved speed indicator herein described for use on
bicycles, tricycles, and the like, so arranged and adapted that it can be adjusted
and secured on the frame of the vehicle at such an angle that the line of sight of
the cyclist may fall perpendicularly, or nearly so, to the tube and its graduated
scale, substantially as described with reference to Figures 1 and 2 of the
drawings.
Third. As a means of transmitting rotatory motion to the glass tube of the speed
indicator herein described, the pulley rim L provided with clamps N and screws P,
whereby the said pulley rim L can be secured to the spokes of a wheel of the
vehicle, substantially as described with reference to Figures 3 and 4 of the
drawings.
Daded thin 10th don of March 1906
Dated this 10th
MARK
March 1906
E. OLDENBOURG,
Per W. H. Beck,
115 Cannon Street, London, E.C., Agent.