Improvements in Multiple Switch Boards.
Year: 1890

page_text: Date of Application, 22nd Oct., 1890
Complete Specification Left, 7th July, 1891-Accepted, 24th Oct., 1891
PROVISIONAL SPECIFICATION.
Improvements in Multiple Switch Boards.
A communication from Mix AND GENEST COMPANY, LIMITED, of 14, Neuen-
burgerstrasse, in the City of Berlin, Germany, Electrical Engineers.
I, CHRISTEN REES BONNE, of 41 Eastcheap, London E.C. Patent Agent do
hereby declare the nature of this invention to be as follows:-
Our invention relates to multiple switch boards and on the drawings herewith the
switching is shewn of the circuit and the apparatus employed.
The jack consists of a shell a in which the key is pushed in, also a contact
spring and a second contact spring d, both of which are attached to the ebonite
plate c.
The contact spring bis in contact with the shell a when at rest, while the
spring d is isolated from a by means of an ebonite plate which is attached either
to d or to a. The contact springs and d are provided with indents o. and o
respectively, which are placed relatively to one another in such a manner that an
inserted key first pushes against the indent o. of spring b and then against the
indent of spring d. To effect contact two keys are used of the construction
shown in Fig. 2, and which have double circuit strings. When the key is inserted
in a jack the point of the key comes first in contact with spring while the
part is in contact with the shell a, but when the key is fully inserted then the
spring brests on the cbonite ring n, the conducting part being in contact with
the shell a while the spring d is in contact with the point k.
As shown in Fig. 1 the apparatus of the subscriber is connected with the circuit
in such a manner that the one circuit branch is attached to the central bar of the
common call key and carried to earth through the alarum W. The branch leads
through the transmitter to the lower contact spring of the automatic switch.
At the station the line is carried to the jack a of the first board, from spring b
to jack a of the second board and so forth through all the boards of the station.
In front of the last jack an annunciator is inserted. This annunciator may by
this arrangement also serve for the purpose of giving the finishing signal. If it is
not required for that, but that office is performed by a special apparatus, then the
annunciator is inserted after the last jack, as shewn in dotted lines marked Kin
drawing.
From the last jack the line leads to a battery R. B, over an adjustable resistance R.
to earth T.
In working this arrangement a number of keys S and S₁ are employed.
For each contact one key S. and one key S¹ are required, the line wires s, s¹, 52, 898
of which are carried to the contacts 5 and 6 of a crank switch U. The contacts 5
and 6 are provided with contact springs, which according to the position of the
crank either get into circuit with contacts 1 and 4 or with contacts 2 and 3.
Under the table plate of the switch are two line-bars I and II of which the
line bar I is connected with contacts 4, while the bar Il is connected with
contacts 1.
The station apparatus consists of a call battery W B, a call key M with the
contacts 1, 2, 3, a sensitive galvanometer G for testing the called line and a
telephone F (in which the microphon current circuit is left out). The contacts 2
and 3 of the switch remain insulated.
The working is as follows:
When at rest the switch U touches contacts 1 and 4. If now a subscriber calls
for instance A, then the current passes through call battery B, line wire
and all

page_text: the jacks whereby the flap on annunciator K A drops. The attendant now pushes
key S into the jack in question, thereby separating the test battery RB from the
line and switches in his speaking instrument, for which the following current circuit
is employed from telephone F through galvanometer G to bar II, switch U,
contacts 1, 5, string s, key S, point k, contact spring, line 2, through the apparatus
of subscriber to line 1, shell a of jack 111 to part of key S', string s³, switch U,
contacts 6 and + to bar T and back to the attendants apparatus. If the subscriber A
demands to speak with subscriber B, then the key S is inserted in the jack of the
subscriber to be called, say for instance jack II of line L. In case the line is free,
and when point . is in contact with spring and part is in contact with shell a,
then the following current is established from battery B to jack spring of
jack 11, k, s, U 5, 1, II, G, E, M, 2, 1, 1, U 4, 6, 8, h, shell a of jack II, line L'
to the apparatus of subscriber B through annunciator W to earth T. The hand of
galvanometer G will move. In case the line were occupied, whether at a jack to
the right or the left of the testing place, then the line will be separated between
parts a and of the jack in question, and the current way from battery would thus
be cut off, and consequently the hand could not move. Given that the hand had
moved and the key were fully inserted then the subscriber B can be called through
the station by means of key M which establishes a current way from W B
over M³, 1, bar I, contacts 4 of switch U, 6, x, h, a, L, apparatus B through
annunciator W to earth.
When the key M is loosened and when subscriber B has taken the telephone
from its hook, then the station is in circuit for speaking through the following line:
from F to G. II U, 1, 5, S¹, k, d, L-telephone branch L,, h, s, U, 4, 1, M, 1, 2
and back to F (over U³, S2 and U6, the line l, is likewise in circuit and
subscriber A can also hear). When both subscribers are in circuit with each other,
then U is placed on 2, 3 and the station consequently out of circuit. The circuit
then passes from both line wires to 5 and 6, where's is in circuit with and st
with 52.
Dated this 7th day of Autahan 1800
C. R. BONNE & Co.,
41, Eastcheap, London, E.C., Authorized Patent and Trade Mark Agents.
COMPLETE SPECIFICATION,
Improvements in Multiple Switch Boards.
Communicated from abroad by Messrs. MIX AND GENEST, of Neuenburger-
strasse 144, Berlin, Gerinany, Electrical Engineers.
1. CHRISTEN REES BONNE of 57 Chancery Lane in the City of London,
Registered Patent Agent, 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 drawing filed with our Provisional Specification represents the construction
of the essential parts of our improved multiple switch boards as employed in
telephone exchanges. The construction is the same as that described in the
Specification of our Patent No. 11941 A.D. 1889 and the apparatus is operated in
a similar way but in this Specification and the annexed sheet of drawings we set
forth the application thereof to suit different circumstances.
We will describe the arrangement shown by the drawing in which the apparatus
of the subscriber is connected with the circuit in such a manner that the one circuit
branch is attached to the central bar of the common call key and carried to
earth through the alaram W. The branch 12 leads through the transmitter to the
lower contact spring of the automatic switch. At the station the line is carried
to the jack a of the first board from spring b to jack a of the second board and so

page_text: forth through all the boards of the station. In front of the last jack an annunciator
is inserted. This annunciator may by this arrangement also serve for the purpose
of giving the finishing signal. If it is not required for that; but that office is
performed by a special apparatus then the annunciator is inserted after the last
jack as shewn in dotted lines marked K in drawing. From the last jack the line
leads to a battery R B. over an adjustable resistance R to earth T.
In working this arrangement a number of keys S and S' are employed.
For each contact one key S and one key S¹ are required. The line wires s, s¹, 5", s³
of which are carried to the contacts 5 and 6 of a crank switch U. The contacts 5
and 6 are provided with contact springs which according to the position of the
crank either get into circuit with contacts 1 and 4 or with contacts 2 and 3 (in the
drawing the switch U is in circuit with the transmitter of the station while
the switch U¹ is out of circuit).
Under the table plate of the switch are two line bars I and II of which the line
bar is connected with contacts 4, while the bar is connected with contacts 1.
The station apparatus consists of a call battery W. B. a call key M with the
contacts 1, 2, 3 a sensitive galvanometer G for testing the called line and a tele-
phone F (in which the microphone current circuit is left out). The contact 2
and 3 of the switch remain insulated.-The working is as follows:-When at rest,
the switch U touches contacts 1 and 4.
If now a subscriber calls for instance A, then the current passes through call
battery B, line wire and all the jacks, whereby the flap on annunciator KA
drops. The attendant now pushes key S' into the jack in question thereby separating
the test battery R B from the line, and switches in his speaking instrument, for
which the following current circuit is employed, from telephone F through galvano-
meter G to bar II, switch U contacts 1, 5, wire s³, key S¹, point k, contact spring d,
line through the apparatus to line l, shell a of jack III to part of key S¹,
wire s³, switch U, contacts 6 and 4 to bar I, and back to the attendant's apparatus.
If the subscriber A demands to speak with subscriber B, then the key S is
inserted in the jack of the subscriber to be called, say for instance jack II of
line L-In case the line is free and when point is in contact with spring band part h
is in contact with shell a, then the following current is established :-From
battery R. B. to spring of jack II, ks', U, 5, s', G. F, M, 2, 1, 1, U, 4, 6, s, h,
shell a of jack II, line L' to the apparatus of subscriber B through annunciator. W
to earth T, the hand of galvanometer G will then be deflected. In case the line
were occupied, whether at a jack to the right or the left of the testing place, then
the line will be separated between parts a and 6 of the jack in question and the
current way from battery would thus be cut off and consequently the hand of the
galvanometer will not be deflected-But if the hand had moved and the key were
fully inserted, then the subscriber B may be called through the station by means of
key M which establishes a current from W B over M, 3, 1, bar I, contact 4 of
switch U, 6, 8, h, a, L', B and W to carth T.-When key M is released and
subscriber B has taken telephone from its hook then the station is in circuit for
speaking through the following line viz. From F to G, II, U, 5, s¹, k, d, L³, L',
a, h, s, U, 6, 4, 1, M, 1, 2, and back to F over U, 5, s², and U, 6, s².
The line is likewise in circuit and subscriber A can also hear.-When both
subscribers are in circuit with each other, then U is placed on 2 and 3 and the
station is consequently out of circuit.-The circuit then passes from both line wires
to 5 and 6, where s is in circuit with and s¹ with s².
8
Having now particularly described. and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
In multiple switch-boards for telephone exchanges, the construction and arrange-
ment of the switches U U' respectively with contact spring at 1, 2, 3, 4, 5, and 6,
whereby through the line bars I and II and the line wires the necessary connections

page_text: are established between the subscribers and the exchange, substantially as herein-
before set forth and described and illustrated by the accompanying drawings.
Dated August. 27th 1891
BONNE & Co.,
Registered Patent Agents, 57 and 58, Chancery Lane,
Agents for the Applicant.