Improvements in Rheostats and Means for Operating the same.
Year: 1899

page_text: Date of Application, 21st Aug., 1899-Accepted, 19th May, 1900
COMPLETE SPECIFICATION.
Improvements in Rheostats and Means for Operating the same.
I, COLEMAN DE KANDO, of Clotild Gasse 22, Budapest, in the Kingdom of
Hungary, 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:-
This invention relates to an improved rheostat wherein compressed air and
liquid is used as a means for operating the changes of circuit.
The annexed drawings illustrate the invention. In putting the rheostat in
the circuit, compressed air contained in a reservoir R is led through a pipe b
and valve 2 partly into pipe c to a valve 4, and partly through a throttle valve 1
into the pipe d from whence it is distributed by the pipes f and e to the short
closer K and to the valve 3 respectively. The compressed air enters with a
greater pressure into the pipe c than into the pipe the entrance to the same
being governed by means of a throttle valve 1. The valve 1 is adjusted according
to the required velocity of putting in circuit. The compressed air passing
through the pipe e closes momentarily the valve 4 which renders the air com-
munication between the water reservoir w and the rheostat chamber possible.
The compressed air flowing in slowly through d passes through the valve 3
which is maintained in a certain opened state by the float 9 by means of its
buoyancy in the liquid in the reservoir of the rheostat. In the position
where the valve 3 is held open and the communication is closed by the
valve 4, the slowly flowing compressed air in pipe g forces the liquid through
the openings ii up into an upper chamber h of the rheostat whereby the suit-
able resistance plates of the rheostat are gradually put into the circuit.
As nearly all the liquid is then in the upper chamber h, the float 9 sinks by
its own weight and closes the valve 3 so that a further in flowing of the com-
pressed air is prevented.
In this position the liquid remains in the chamber has the same is suitably
water-tight, the rheostat plates being thus kept in the circuit.
The short closing of the binding clamps of the rheostat is then automatically
effected without the liquid leaving the chamber h.
This takes place in the following manner: The valve 3 being already closed,
the air flowing in through the throttle valve is collected in the pipes d e f until
the pressure therein has reached the pressure in the air receiver R and in over-
coming the pressure of spring L lifts the plate or switch m so that it touches the
contact pieces n n wherewith the desired short closure is attained.
The putting out of circuit is done by means of the valve 2 in connecting the
pipe c with the free air. By the diminishing of the pressure in the pipe f the
plate or switch m is removed from the contact pieces n n by the spring L
and the compressed air flowing out of c allows the valve 4 to open again. The
compressed air in the chamber w then passes through the pipe g and valve 4
which is now open into the chamber h and allows the liquid to fall back by its
own weight into its original receiver so that the circuit is interrupted.
The construction of the valves is shown in Figs. 2 to 5 and the construction

page_text: of the short-closer in Figs. 6 and 7, which demonstrate the action of the device
in connection with a controller for traction purposes. Fig. 2 represents the
outlet valve 4; Fig. 3 the valve 3; Figs. 4 and 5 the throttle-valve in con-
nection with the regulating valve 2; Figs. 6 and 7 represent the plate m of
the short-closer, which consists of electrically conductive material and effects
the electrical short-closure by contact with the contacts in the manner
described.
Having now particularly described and ascertained the nature of my invention
and in what manner the same is to be performed, I declare that what I claim is :—
1. An improved rheostat actuated by means of compressed air in which the
admission of the compressed air is regulated by means of a throttle valve 1, and
in which a pipe junction is arranged before the throttle valve 1 and behind the
valve 2 for the automatic actuation of an escape valve 4.
2. In a rheostat as in Claim 1 the arrangement of a valve 3 which is opened
and closed by means of a float 9 accordingly as the liquid is forced into the
rheostat chamber or flows back out of the same into the reservoir containing the
float.
3. In a rheostat as in Claim 1 the arrangement of a pipe f behind the throttle
valve 1 governing automatically a short closer K by the increase of the air pres-
sure in produced by the closing of the valve 3.
· Doted this 21st day of August 1899
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HERBERT HADDAN & Co.,
Agents to Applicant,
18, Buckingham Street, Strand, W.C., London.
HERBERT HADDAN & Co.,
Agents to Applicant,
18, Buckingham Street, Strand, W.C., London.