Improvements. in Means for the Automatically Regulated Charging of Electrical Accumulators.
Year: 1898

page_text: Date of Application, 3rd Aug., 1898--Accepted, 1st Oct., 1898
COMPLETE SPECIFICATION.
Improvements. in Means for the Automatically Regulated Charging
of Electrical Accumulators.
I, CHRISTIAN ULRICK EMIL PETERSEN, 81, Österfarimagsgade, Copenhagen, Den-
mark, Doctor of Philosophy and Chemist, 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 method and apparatus have for object to effect the loading of electrical
accumulators in such manner that when the accumulator battery has been used or
spent the connection between the accumulator battery and the supply circuit is
broken and at the same time connection is made between the accumulator and the
source of electricity or the charging current by actuating a handle or button;
furthermore so that the last named connection is automatically broken when the
accumulator battery has been fully charged, and lastly so that when the accumulator
is to be put to use again the actuating of the handle or button again closes the con-
nection with the consumer or supply circuit, while simultaneously the connection
which has been broken between the accumulator and the source of electricity at the
end of the charging is again automatically closed so that the charging when the
connection between the accumulator and the supply circuit is broken, begins afresh
and the same phenomena are repeated.
The method can be applied to and the apparatus used with any source of electricity.
The method and apparatus remain in principle and in all essentials the same; but
according as the charging is effected 1/ by means of galvanic elements or 2/ by
means of a thermopile or 3/ with high tension current from an electric central
station parts of the apparatus are modified in some details, wherefore each of these
cases is treated of separately.
1. CHARGING BY GALVANIC ELEMENTS.
Fig. 1 of the accompanying drawings is a diagram of the apparatus and circuits
used therein..
A is one of the cells of the accumulator battery, closed airtight with exception of
an upper opening having a stopper 12 with three through passages. Through the
two are passed the twice bent glass pipes s and having funnels and containing pure
quicksilver in the two outer branches. Into the glass pipes are fused platinum wires
that is in the pipe r two wires one in each of the two outer branches and at the same
level, and in the pipes likewise two wires, but here in the same outer branch and at
different levels. E is a valve which can be opened by means of a little electro
magnet. The poles of this are as shown on a bail shaped piece of hoop iron 1;
over an opening in the upper member of it is screwed on a brass cylinder 2 through
which passes the valve tube 3 also of brass. The tube 3 fits tightly in the cylinder 2
so that it can be pushed up or down and held at any level. In Fig. 2 is shown a
full size section through the valve tube which has an upper fixed ring 4 that serves
for guiding the valve rod 5 and as abutment for the spring that keeps the valve
closed and is fixed below. to the valve rod 5. The latter has also below a head 6 of
Price 8d1

page_text: the form shown having a lower recess containing a ring 7 of socalled Jenkins washers.
Into this is pressed an annular projection on the plug 8 which is screwed into the
end of the valve tube and closes it. To the end of the valve rod is screwed the
keeper 9 of the electro magnet Fig. 1. Through this keeper pass also two small
pegs from the poles, for guiding the keeper. When no current passes through the
coils of the electro magnet, the spring presses the Jenkins washers airtight against
the annular projection of the plug 8 and thus keeps the valve E closed; when the
distance between the armature and the poles of the electromagnet is regulated by
pushing the valve tube up or down and when thereupon a suitable current is sent
through the coils, the armature is attracted and the valve opened, the end of the
valve rod being triangular in section; the air then passes easily between the valve
rod 5 and the plug 8. The other end of the valve tube 3 Fig. 1 is continued as a
tube which by a narrower down pipe 11 passes through a third hole in the stopper 12
in the closed accumulator cell and makes communication with the interior of the
latter.
L is a glow lamp of suitable size inserted into the working circuit in order to show
whether the connection between it and the accumulator battery is closed or broken.
K is an ordinary double contact such as can be bought in the shops; it can alter-
nately put in electric connection two opposite terminal screws and insulate two
others.
Lastly at the sides of the accumulator are arranged a voltmeter 13 and an ampere-
meter 14. On the drawing the connection II-II on the double contact is shown
closed, and the accumulator is thus connected with the charging battery, while the
connection between the accumulator and the working (lamp) circuit is broken. From
the positive pole 15 of the battery B the current passes through the ampere meter 14,
the contact K and wire b to the positive accumulator pole 16 from the negative
accumulator pole 17 through the wire c, the quicksilver in the pipe (provided the
charging has not been completed) and the wire d back to the battery. When
the charging is done the current is automatically interrupted by the quicksilver
in the pipe r, because the quicksilver by the pressure of the gas that evolves in the
accumulator cell after the charging has been completed rises in the branch to
the right while that in the branch to the left sinks below the platinum wire. The
gas evolution does not cease in the same moment as the circuit is broken, but con-
tinues a little after so that the quicksilver when left standing may drop more than
two centimetres below the platinum wire.
The break of the circuit is indicated by that the movement of the hand on the
inserted amperemeter 14 ceases.
Simultaneously the quicksilver rises in the left branch of the pipe 8 and there
makes connection between the two platinum wires fused therein and which are
inserted in a circuit between the accumulator and the electromagnet; this circuit is
however now broken by the contact (the connection I-I).
When the contact discs are turned one fourth the following takes place.
The connection through the contact between the battery B and the accumulator A
is broken and simultaneously the connection is closed between the accumulator and
the electromagnet as well as the working (lamp) circuit. From the positive
accumulator pole the current passes through the wire e, the electromagnet coils,
the wire f, the quicksilver in the pipe s, the wire g, the contact, the wire b back to the
accumulator. Thereby the armature is attracted the valve 6 is opened and equalizes
the pressure in the accumulator cell whereby the quicksilver comes to the same level in
the branches of the pipes and the pipe r. The connection between the accumulator
and the electro magnet is thus broken in the pipe a while in the piper the
connection between the accumulator and the charging battery being now interrupted
in the contact K, is established. As the current ceases in the electro magnet, the
electro magnet again moves away from it and the valve closes the pipe 3. But the
circuit connection between the accumulator and the working circuit remains closed.
From the positive accumulator pole the current passes through the wire i the
lamp, the wire k the contact and the wire h back to the accumulator. If the

page_text: there is then a fourth one whereby the interior of the cell can be connected with
a thermo regulator, which closes the gas pipe to the thermopile a little after that the
connection between it and the accumulator battery is broken and opens a little before
the said connection is again established the lights in the thermopile being lighted by
a small constantly burning jet on a separate conduit.
3. CHARGING BY HIGH TENSION CURRENT FROM A CENTRAL STATION.
When it is desired to charge an accumulator battery by means of a high tension
current from an electric central station it is generally done for transforming it to a
current of lower tension without loss of energy. This may be done by employing a large
number of accumulator cells and to charge them when they are connected in highest
tension hence one after the other. In discharging the whole battery is divided into
a certain number of groups of cells having an equal number of cells in each, according
to the tension desired and all the cell groups are then simultaneously discharged
connected in multiple arc, all the positive poles of the groups being now connected
and so also all the negative.
This charging and discharging may be done by the apparatus described and in a
similarly easy manner as before, if instead of the simple double contact another and
larger one be used. Such an one adapted for a special given instance is shown in
Figs. 3 to 10 and B in different positions and consists of two porcelain discs at
least one centimeter thick and provided at the edge with a definite number of
notches so that it assumes the form of a pawl wheel. The number of teeth in each
wheel is four times the number of the cell groups wherein the accumulator battery is
desired to be divided. The pawl wheels are arranged concentrically over each other
on the same spindle but insulated from each other by an intervening disc of cardboard
or rubber. The spindle below passes through a fixed large porcelain disc having
along the edge and around the pawl wheel a number of terminal screws insulated
from each other and provided with spring contacts that take into the pawl teeth.
The fixed porcelain disc has underneath notches for the insulated wire conduits (like
the ordinary double contacts). If the number of cell groups wherein the accumulator
battery is divided, be n then the number of terminal screws with spring contact
therefor is 4 x n + 2. Both the pawl wheels can by means of a handle on the
spindle be turned in the direction of the arrows shown.
:
On the drawing is shown a diagram that illustrates the state of things with an
accumulator divided into four cell groups which for clearness sake are shown. separate.
For the same reason the two pawl wheels are shown separate with their separate
terminal screws contacts and wire conduits, while they in reality as stated are placed
concentrically, the one Fig. 3A to the left below, and the other, Fig. 3B, above.
The two pawl wheels have different brass covering conducting strips indicated by
section lines. On the lower wheel Fig. 3A there are four teeth covered by a strip of
thin sheet copper covering four teeth down the side of the wheel but not down round
the edge of the last tooth (in Fig. 3 in touch with the spring contacts: from the
terminals I and I). Then follow four teeth without covering strip and then
four teeth with a similar covering and lastly four teeth without covering. The cell
groups are marked I II III and IV and the terminal screws are denoted by the poles
whereto they are connected, viz. : + I,
-
I and so on.
Besides the eight terminal

page_text: screws thus marked there are two marked V and L. The spring contacts on these
as on the terminals + I and I have a width of only about of the thickness of
the pawl wheel. The contacts from the terminals V and L slide on the lower third
part of the teeth. The contacts from + I and - I slide on the upper third part of
the teeth, so that the terminals +I and I are insulated respectively from the
terminals V and L as soon as the said contacts touch a not covered tooth of the
wheel.
:
On the upper pawl wheel are likewise eight covered and eight not covered teeth,
four covered and four not covered alternating but the mode of covering is here
different as it is intended to connect electrically four of diametrically opposite teeth
on the wheel but insulate them from the adjoining teeth. The edge of a tooth is
covered with a copper strip the width of which is only one third of the width of the
tooth and is at the bottom or notch end as shewn in Fig. 3. By means of a flat
ring which insulates it from the spindle it is connected to a similar covering strip on
the diametrically opposite tooth; the whole forms one piece cut out of thin sheet
copper. Upon the covering strip of the first pair of teeth is placed an insulating
rubber or cardboard disc, and over that is brought a similar conducting covering
for the next pair of teeth, then again a rubber disc and so on. When all eight
teeth have in this manner been connected in pairs but insulated from their
adjoining teeth, the two pawl wheels with their covering strips and insulating discs
are pressed firmly together by means of a nut on the spindle, which latter is of square
section in its lower part as shewn in Figs. 34 and 3 but of cylindrical section and
screw threaded in its upper part. The spindle with the wheels can be turned in the
direction of the arrow, and can be kept in any position by means of a spring arranged
round the spindle in a similar manner as in the ordinary contacts for electric
lighting plant.
Figs. 3 and to Figs. 10 A and B shew the eight positions of the pawl wheels
which are possible with the number of sixteen teeth on each and the contacts and
terminals belonging to them. Figs. 3 to 10 shew the lower pawl wheel, and
Figs. 3 to 10 the upper, each pair of opposite figures marked with the same
number denoting corresponding positions.
B
The two pairs of figures Figs. 3* and B and Figs. 7* and " shew the two positions
which the pawl wheels should assume respectively while discharging and charging.
The other positions shewn on the drawing are those which the pawl wheels take
successively and in passing during the rotation, but none of which are actually utilized.
The intermediate positions are indicated in order to shew that no short circuits
or the like can be made which might eventually damage the apparatus or the
circuits.
Fig. 3 shews that the positive poles on all the cell groups are conductively con-
nected with each other, and also all the negative, while the circuits to the upper
dise Fig. 3 are all insulated from each other. The current passes partly through
the working circuit (lamp L) and partly through the terminal screw V via the volt-
meter, the other terminal screw of which may be directly connected with the negative
pole of the cell group No. IV.
This position is therefore the position which is to be used during the employment,
the discharge, of the accumulator battery.

page_text: voltmeter are cut out and the hand goes back provided these connections have not
been already interrupted (see below under the 6th position).
1
On the upper wheel the terminal screws I and the + 2 are connected.
Fig. 8B shews the contacts
1 and 2 insulated, nence the cell group No. 1 is
disconnected from the other groups. Fig. 84 shews that the cell group No. 1 sends
its current through the electro magnet coils, yet only for a moment, until
the connection in the pipe S is interrupted again by the opening of the
valve.
If the resistance in the voltmeter is not large enough and it is not calculated to
shew so high a tension as the current from the central station has, the connection
between the voltimeter and the terminal V here and in the following positions must
be broken, as otherwise the station current would pass through the voltmeter.
Altogether the voltmeter only serves off and on to control, during the use of the
accumulator, that its tension has not sunk below the admissible valve, (m x 1.8)
where m is the number of cells in each cell group, and the connection between the
terminal V and the voltmeter is normally broken, as otherwise a needless loss of
energy would be entailed.
From the same reason the working circuit from + I and 4 here and in the following
two positions is broken and not, as shewn on the drawing, closed through a lamp
as otherwise the station current goes through it.
In practice it will of course always be the case, as the working or consuming circuit
ought not to be closed before the pawl wheel contacts have the position which is right
for the use of the accumulator battery as in Figs. 3ª and B.

page_text: The cell groups I, II and III are here connected in multiple arc, and IV is insu-
lated from them. When the wheels are turned into the next position it will be
seen to be the same as the first position Figs. 3A and B.
In order to avoid needless complication in the description I have in the above
example shewn a division of the accumulator battery in four cell groups, but it will
be evident that the same process in the charging and discharging can be used with
a division into a greater number of cell groups, and the pawl wheel contacts will
then have a correspondingly greater number of teeth, with terminal screws belonging
thereto.
The advantages obtained by the aforesaid process of charging are the following:
The connection between the working (consumer) circuit or the charging current
respectively with the accumulator is closed or broken by merely turning a handle.
As the connection with the charging current is fixed, there is no possibility for a
wrong connecting up of the poles and a consequent discharge of the accumulator.
The interruption of the connection with the charging current is effected auto-
matically by the apparatus when the charging is finished, so that needless over
charging and thereby waste of energy from the source of electricity is quite
avoided.
The charging begins automatically in the same moment that the connection with
the consumer circuit is broken, and the accumulator battery is thus always ready for
use a spontaneous discharge of the accumulator when it has been standing idle is
remedied by the charging current.
Lastly I have under the third head described a simple method for transforming
high tension currents to lower tension currents without loss of energy and for
similarly keeping the accumulator battery used therefor fully charged.
The process therefore combines the following advantages.
Simplicity of manipulation, safety in the use and cheapness in the utilization of
the source of electric energy.
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. In an accumulator battery the arrangement of a valve in a pipe or other air
current outlet conduit from an airtightly closed accumulator all said valve connected
to the armature of an electro-magnet which is so arranged that when current passes
through the electro-magnet coils and the armature is attracted in consequence, the
valve is opened, while otherwise it is kept closed, and so that the electro magnet
coils can be connected with the poles of the accumulator battery through a contact
such as quicksilver in a bent glass pipe 8 communicating with the said accumulator
cell which contact is closed by that the quicksilver rises in consequence of the rise
of pressure in the cell, in combination with another contact such as quicksilver in
a glass piper communicating with the same cell, said contact being inserted in the
conductor between one of the accumulator poles and the corresponding pole of the
current source in such manner that the contact is broken by rise of pressure in
the accumulator cell, for the purpose of obtaining the automatic interruption of the
connection between the accumulator and the source of current, when the charging

page_text: is finished, and is resumed when the accumulator after use is disconnected from
the consumer circuit.
2. In combination with the arrangement firstly claimed a multiple contact con-
sisting of two porcelain discs or the like so arranged that they turn together, said
discs provided with teeth in number four times that of the number of cell groups,
one disc covered with conducting material in such manner that a number of adjoining
teeth equal to the number of cell groups are conductively connected with each other
and alternatingly with a similar number of adjoining teeth not conductively
connected, contact springs being arranged against the disc in a number equal to four
times that of the cell groups plus two, said contact springs arranged and connected
with the cell groups in the manner indicated by Fig. 34 while the teeth on the
other disc of the group corresponding to the number of the cell groups alternately
are not conductive but covered with conductive material in such manner that the
adjoining teeth are insulated from each other, while each tooth is conductively
connected with the diametrically opposite tooth, the disc having contact springs
dragging on its teeth in number equal to four times that of the number of cell
groups, said springs being arranged and connected with the cell groups in the
manner indicated by Fig. 3B all for the purpose of obtaining the aims stated in
Claim 1, while the cells by adjusting a single contact during the charging may be
connected at highest tension, and during discharge may by turning and adjusting
the same contact be connected at lower tension.
Day of August 100.
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.