An Automatic Charging Device for Electric Motor Carriages.
Year: 1899

page_text: Date of Application, 27th Oct., 1899
Complete Specification Left, 24th May, 1900-Accepted, 30th June, 1900
PROVISIONAL SPECIFICATION.
An Automatic Charging Device for Electric Motor Carriages.
I, ALBERT MÜHLBERG, of Jaegerstrasse 6, Berlin, in the Kingdom of Prussia,
Germany, Engineer, do hereby declare the nature of this invention to be as
follows:
In electric motor carriages, the batteries of which are so constructed as to
require recharging while in course of operation, it is important that the time
occupied in charging should be as short as possible, seeing that during that
time the carriage is unavailable for operation or traffic. To avoid the necessity
of depending upon the greater or less punctuality of the staff of atten-
dants, it is advisable to provide at the charging stations, means
making connections between the poles of the carriage battery and those of the
charging machine.
"
for
The arrangement adopted to this end may consist of two tightly stretched
wires or contact rails extending over the part where the charging takes place,
for the carriages to pass under, and make contact with by means of two
trolleys," rollers or brushes, so that the connection is formed between the
poles of the machine and those of the battery. Or, as in the case with regard
to electric street carriages worked by means of overhead conductors, one pole
of the machine may be placed on the ground and the other on the overhead
conductor.
At the beginning of the charging operation there occur powerful current
rushes or impulses, which, where the current is obtained from an electric
lighting system or from a small installation of machines, have to be reduced
by the insertion of a regulating resistance. These current rushes also occur
in so called mixed systems, where some lines are worked with battery current,
while others receive current by contact, from conductors, and where, while
The
current is supplied by the conductors, the batteries must be charged.
arrangement hereinafter described is, accordingly, intended, in this system of
electric motor-traffic, to enable the batteries to be charged with a nearly constant
amount of current.
It is the object of this invention to render it unnecessary to switch the
resistance into and out of the circuit by hand, and to this end a positive contact-
conductor or a rail, is divided into two or more pieces insulated from each other
which are so connected with the positive pole of the charging machine, by means
of permanent (or stationary) resistances inserted into the circuit in front of
them, that the part of the conductor standing foremost in the direction of
motion of the carriage, meets the maximum resistance so switched in, while the
next following part meets with a reduced resistance, and at the last part the
resistance is short-circuited.
Now the operation is as follows:
The carriage whose charge is exhausted comes up under the contact conductor
nd then first nont of the come as full resistance is here switched

page_text: in, the current impulse occurring first is materially reduced. The carriage now
slowly proceeds under the other divisions of the conductor and eventually
arrives at the last division. If the several divisions or parts be made sufficiently
long, the carriage will thereby be enabled to travel any given distance during
the charging operation and the length of the several parts may be so deter-
mined in accordance with the charging curve of the carriage battery that the
charging will be performed with a practically constant amount of current, which,
as far the batteries are concerned, is the most beneficial method of charging.
Besides the overhead conductor may be so long that a number of carriages
may be charged one after the other at one operation and their motion may at
the same time be so regulated as to cause the carriage to advance in such a
manner or at such a rate that the charging current shall be approximately
constant. The two contact conductors may be arranged in the most diverse
positions, say in a slot or channel in the bottom, and one of the contact-conductors
may moreover, consist of rails.
T
871
1000
An Automatic Charging Device for Electric Motor Carriages.
I, ALBERT MÜHLBERG, of Jaegerstrasse 6, Berlin, in the Kingdom of Prussia,
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; -
In electric motor carriages, the batteries of which are so constructed as to
require recharging while in course of operation, it is important that the time
occupied in charging should be as short as possible, seeing that during that
time the carriage is unavailable for operation or traffic. To avoid the necessity
of depending upon the greater or less smartness or promptitude of the staff of
attendants, it is advisable to provide at the charging stations, means for
making connections between the poles of the carriage battery and those of the
charging machine.
The arrangement adopted to this end may consist of two tightly stretched
wires or contact rails extending over the part where the charging takes place,
for the carriages to pass under, and make contact with by means of two
"trolleys," rollers or brushes, so that the connection is formed between the
poles of the machine and those of the battery. Or, as in the case with regard
to electric street carriages worked by means of overhead conductors, one pole
of the machine may be placed on the ground and the other on the overhead
conductor.
At the beginning of the charging operation there occur powerful current
rushes or impulses, which, where the current is obtained from an electric
lighting system or from a small installation of machines, have to be reduced
by the insertion of a regulating resistance. These current rushes also occur
in so called mixed systems, where some lines are worked with battery current,
while others receive current by contact, from conductors, and where, while
current is supplied by the conductors, the batteries must be charged.
arrangement hereinafter described is, accordingly, intended, in this system of
electric motor-traffic, to enable the batteries to be charged with a nearly constant
amount of current.
The

page_text: The application of this invention is represented in Fig. 1 in a side elevation
and in Fig. 2 in a front elevation.
It is the object of this invention to render it unnecessary to switch the
resistance into and out of the circuit by hand, and to this end a positive contact-
conductor A or a rail, is divided into two or more pieces, I, II, III, insulated
from each other which are so connected with the positive pole of the charging
machine, by means of permanent (or stationary) resistances inserted into the
circuit in front of them, that the part of the conductor I standing foremost in
the direction of motion of the carriage, meets the maximum resistance so
switched in, while the next following part II meets with a reduced resistance,
and at the last part III the resistance is short-circuited. The negative contact-
conductor B consists of a single piece.
Now the operation is as follows:
The carriage whose charge is exhausted comes up under the contact-conductor
and first stops under the first part I of the same, as full resistance is here
switched in, the current impulse occurring first is materially reduced. The
carriage now slowly proceeds under the other division II of the conductor and
eventually arrives at the last division III. If the several divisions or parts be
sufficiently long, the carriage will thereby be enabled to travel any given
distance during the charging operation and the length of the several parts may
be so determined in accordance with the charging curve of the carriage battery
that the charging will be performed with a practically constant amount of
current, which, as far the batteries are concerned, is the most beneficial method
of charging.
Besides the overhead conductor may be so long that a number of carriages
may be charged one after the other at one operation and their motion may at
the same time be so regulated as to cause the carriage to advance in such a
manner or at such a rate that the charging current shall be approximately
constant. The two contact-conductors A and B may be arranged in the most diverse
positions, say in a slot or channel in the bottom, and one of the contact-conductors
may moreover, consist of rails.
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:-
1. An automatic charging device for carriages driven by means of accumu-
lators or storage batteries, the main feature of which is that one of the two
contact-conductors, past which the battery poles slide or sweep through the
medium of trolleys, rollers, brushes or the like, is divided into two or more
insulated lengths or divisions, which are so connected with one pole of the
charging machine or source of current by means of resistances switched in front
of them, that the division placed foremost in the direction of motion of the
carriage has the maximum resistance switched before it, while at the succeeding
divisions such resistance becomes gradually less and is short-circuited at the last
division of all.
2. In the arrangement claimed in the First Claim, determining the lengths
of the several divisions in accordance with the charging curve, so that while
the carriage is in motion it is charged with an approximately constant amount
of current.