IMPROVEMENTS IN TELEPHONIC " APPARATUS APPLICABLE ALSO. TO OTHER. PURPOSES
Year: 1883

page_text: LETTERS PATENT to Louis John Crossley and Walter Emmott both of Halifax,
in the county of York for an Invention of IMPROVEMENTS IN TELEPHONIC
"
APPARATUS APPLICABLE ALSO. TO OTHER. PURPOSES
دو
PROVISIONAL, SPECIFICATION left by the said Louis John Crossley and
Walter Emmott at the Office of the Commissioners of Patents on the
27th February 1883.
"
. LOUIS JOHN CROSSLEY and WALTER EMMOTT both of Halifax in the County.
of York 'IMPROVEMENTS IN TELEPHONIC APPARATUS APPLICABLE ALSO TO OTHER
PURPOSES.""
C
This invention relates to a new form of electrical indicator or relay specially
adapted for use in Telephone Exchanges but which is applicable also to other
purposes.
In the working of Telephone Exchanges it is found that considerable delay is
caused where the subscribers have not some means independent of the calling
signal of indicating in the Exchange that the lines are at liberty and may be put
back ready for the next call,
.
To overcome this defect we have arranged an indicator or relay having a
swinging needle or needles which can if desired be adjusted by a weight, magnet,
spring or by any other suitable means near the pole or poles of an electromagnet
in such manner that the rapidly alternating currents of electricity generated by
a double current magneto generator now so largely in use will not deflect the
needle definitely in either direction but on a current in one direction alone being
sent, the needle will be deflected so as to close a local circuit and drop a mechanical
indicator or other suitable means to attract the operator's attention. The needle
may also be so arranged as to remain in the deflected position until put back by
the operator
In addition to its use in telephone word, this indicator may be used in block
signalling instruments, light indicators and signal indicators together with other
electrical signalling instruments on railways and also at intermediate telegraph or
telephone stations where it is desired to avoid switching; the indicators may also
be usefully applied to other purposes;

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Louis John Crossley and Walter Emmott in the Great Seal Patent
Office on the 22nd August 1883.
LOUIS JOHN CROSSLEY and WALTER EMMOTT both of Halifax in the county of
York IMPROVEMENTS IN TELEPHONIC APPARATUS APPLICABLE ALSO TO OTHER
"
PURPOSES
"
The said invention relates to a new form of electrical indicator or relay specially
adapted for use in telephone exchanges but which is applicable also to other
purposes.
In the working of telephone exchanges it is found that considerable delay is
caused where the subscribers have not some means, independent of the calling
signal, of indicating in the exchange that the lines are at liberty and may be put
back ready for the next call.
To overcome this defect we have arranged an indicator or relay having a
swinging needle or needles which can if desired be adjusted by a weight, magnet,
spring or other suitable means near the pole or poles of an electro magnet in such
a manner that the rapidly alternating currents of electricity generated by a double
current magneto generator, such as those now so largely in use, will not deflect
the needle definitely in either direction, but on a current in one direction alone
being sent, the needle will be deflected so as to close a local circuit and drop a
mechanical indicator or other suitable means of attracting the operator's attention.
The needle may also be so arranged as to remain in the deflected position until put
back by the operator.
In addition to its use for telephonic purposes this indicator may be used in block
signalling instruments, light indicators, and signal indicators together with other
electrical signalling instruments on railways, and also at intermediate telegraph or
telephone stations where it is desired to avoid switching. The indicators may also
be usefully applied to other purposes.
In order to enable our improvements to be fully understood we will proceed to
describe the same by reference to the accompanying drawing which illustrates
a suitable method of carrying our invention into practice and in which figure 1,
represents a front view of the indicator or relay; figure 2, is a side view and
figure 3, a plan of the same. Similar letters of reference are employed to represent
similar parts.
A is the indicator or relay constructed with the swinging needle B, (or needles)
which can be adjusted by the weight C, or by a magnet, spring, or other suitable
means near the pole or poles D, of an electro magnet E, in such a manner that the
rapidly alternating currents of electricity generated by a double current magneto
generator such as those now so largely in use, will not deflect the needle B,
permanently in either direction; but on a current or series of currents in one
direction alone being sent, the needle B will be deflected so as to close a local
circuit or drop a mechanical indicator or otherwise attract the operator's attention.
The needle B, may also be so arranged as to remain in the deflected position until
put back by the operator by allowing the needle B to come into contact with
either of the poles D.
There are numerous other useful applications of these improvements for instance
an intermediate station can be arranged with two terminal stations so that the
terminals can speak with each other or with the intermediate station, the switching
being done by the station wishing to speak as will be well understood from the
foregoing explanation without further description.

page_text: The improvements are also applicable to the working of electric signals on
railways instead of using batteries as at present, for example, the "ring off" key
or other suitable arrangement will enable the operator to transmit the currents so
as to indicate "line clear" and "line blocked" or otherwise, as required.
Having thus described our invention and a suitable manner of carrying the same
into effect, we wish it to be understood that what we claim is :—
The manufacture and use of indicators or relays constructed with a swinging
needle or needles arranged and operating substantially in the manner and for the
purposes hereinbefore described.
In Witness whereof I the said Walter Emmott for and on behalf of myself
and the said Louis John Crossley have hereto set my hand and seal this
twenty first day of August in the year of our Lord one thousand eight hundred
and eighty three
Witness,
WALTER JAS, TURNER C.E.
Patent Agent
Bradford
WALTER EMMOTT (L.S.)