Year: 1895

page_text: Date of Application, 19th Dec., 1895-Accepted, 17th Oct., 1896
Apparat
I, JACOB WOLFF of Brühl bei Köln a/Rh. in the Empire of Germany, 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 :-
If vertical tubes open at the bottom are secured all round the circumference of
the lid of a centrifugal vertical drum or cylinder, containing any liquid, the latter
will ascend in such pipes to a height proportionate to the speed at which the drum
or cylinder is made to revolve.
The rotary-speed indicator described in this specification is constructed on the
above principle.
In the form represented in Fig. 1, the side-wall (i) of the metallic cylinder (a)
is prolonged in an upward direction beyond the lid (c), and forms with the glass
tube (d) (fastened in the foundation (e), with putty), a narrow chamber (b), of
tubular shape. The latter communicates at the lower end with the interior of the
cylinder, by the openings (f).
The said cylinder contains a liquid easily distinguishable, say, coloured alcohol.
This liquid, when the apparatus is at rest, stands in the chamber (b) at the same
level as in the cylinder.
By giving the apparatus a circular motion on its vertical axis, the liquid will
rise in the chamber (6), proportionately to the rate of speed at which the cylinder
is revolving.
Therefore, the height of the liquid in the chamber (b) indicates the acquired
speed. Vertical walls are arranged in the cylinder in order to make the rotary
motion of the latter affect the liquid as soon as possible.
The lid of the cylinder (c) is provided, at its centre, with a small opening (h) by
which means the pressure of air on the liquid in the chambers (a, b) finds its
equilibrium. It is preferable, however, to close the chambers (a, b), at the top,
and to create a vacuum there in order to prevent the formation of air bubbles,
which might affect the indications as shewn by the apparatus.
If the same apparatus is to serve for both high and low rates of speed; the
conical shape shewn in Fig. 2 should be adapted.
The form shewn in Fig. 2 may be provided with an electric bell device, to
announce when a certain speed is exceeded. In this case, the chambers (a, b) are
formed of a single glass body void of air. The cylinder contains any liquid which
is a good conductor of electricity, mercury, for example.
The connecting wires of the electric bell terminate in two metallic strips near the
base of the foundation or socle of the apparatus. One of them lightly touches
the base itself; the other, the metal ring (1), which is isolated on the base. From
the ring, a platinum wire (m) is drawn, passing upwards through the foundation,
thence through the glass wall (n), and finishing in the chamber (6). On the other
hand, the liquid in the cylinder (a) is placed in communication with the base by
another platinum wire (o) introduced into the glass wall. As soon as the
appointed speed eis exceeded, the upper platinum wire (m) touches the liquid,
thereby completing the circuit and causing the signal to sound until the speed is
reduced to its normal rate.

page_text: Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
-claim is :
An indicator of rotary speed, distinguished by two concentric chambers (a, b)
revolving round a vertical axis, the first of which forms, so to speak, the chamber
of a centrifugal cylinder and contains any liquid of a convenient and suitable
nature, whilst the other chamber (b), situated on a higher level, is shaped like a
pipe with a thin wall, and is in communication at its lower end with the chamber (a)
so that by the action of centrifugal force, the liquid is made to ascend in the
chamber (b) in proportion to the increase of rotary speed, the whole as described in
the above specification and shown in the accompanying drawing:
Dated this 19th day of December 1895.
L. DUVINAGE,
Agent for Applicant.