Improvements in speed Gauges.
Year: 1895

page_text: Date of Application, 26th Nov., 1895-Accepted, 28th Dec., 1895
Improvements in speed Gauges.
I, HEINRICH SCHLOTFELDT, Engineer, of Kiel in the Empire of Germany, 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 present invention relates to speed gauges in which, by rotation of a centri-
fugal apparatus moving a fluid, a gaseous pressure is produced which corresponds
to the velocity and is indicated by the gauge.
The novelty of the present invention is a particular arrangement of the centrifugal
apparatus, by which arrangement the stuffing-boxes, required in similar apparatus,
are avoided, and in an adjustment by which the measure of the atmospheric
pressure corresponding to a fixed or certain velocity or number of rotations can be
exactly regulated.
The invention is shown in the annexed drawings.
Figs. and 2 show the exterior view of the apparatus in elevation and in plan
respectively.
Fig. 3 is a vertical central section. Fig. 4 is a plan in section on line c-d of
Fig. 3.
L is a shaft turning in a vertically arranged cylinder C which shaft is driven by
ineans of bevelled gearing from the shaft the number of revolutions of which are to
be indicated. The lower end of shaft L carries the centrifugal disk K through
the lateral holes of which the fluid, drawn in at the lower end of the shaft L, is
thrown out.
As a liquid, mercury is preferable and is contained in a second reservoir A and
in a float or air vessel B in said reservoir, and in the axis of which a tube R, closed
above and open below is fastened, possessing holes pierced through it into the
interior of the float at the upper and lower part of the same. The tube R
surrounds a tube open above and communicating below with the pressure
gauge and is connected by means of a passage R' with the lower open end of
the shaft L, while the reservoir A is connected by means of passage R³ with the
space in which the disk K revolves.
In this arrangement the essential novelty for avoiding stuffing-boxes is that the
rotary body K is arranged on a shaft L, put vertically into the enclosing
cylinder C, through which shaft the mercury must rise from below, the remaining
space of the cylinder C being filled by a body D in order to fill up the unrequired
space.
When the body K is brought into rotation the mercury is drawn from the
float B (through tube R and passage R¹) and forced into chamber A through
passage R². By this process the air in chamber B, the tube and the tuber
leading to the pressure gauge is exhausted or rarified. The measure of rarifaction
is proportional to the speed of rotation of the body K. In order, however, to
regulate the measure of the atmospheric pressure in B exactly for a fixed number
of revolutions, an adjusting spindle or pin H has been added by means of
which the opening of a passage R³ connecting the passages R' and R³ can be
adjusted.
When H is raised from its seat more or less, more or less liquid will run
through passage R³ and the atmospheric pressure in float B is lessened more
or less.

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 ;-
In speed gauges with aerial pressure produced by rotation of a centrifugal
apparatus moving a liquid, for avoiding packings and using mercury as the
operating liquid, the vertical shaft L open below for raising the mercury to the
centrifugal body K in combination with a regulating screw H adapted to open
more or less a passage R³ which connects the suction passage R' with the force
passage R².
Dated this 26th day of November 1895.
HERBERT HADDAN & Co.,
18, Buckingham Street, Strand, London, W.C.,
Agents to the Applicant.