Automatic Time Switch for Trunk Lines.
Year: 1891

page_text: Date of Application, 13th Oct., 1891
Complete Specification Left, 13th July, 1892-Accepted, 10th Sept., 1892
PROVISIONAL SPECIFICATION.
Automatic Time Switch for Trunk Lines.
We, PERCIVAL PHILIP KIPPING, trading as P. P. Kipping and Co.,
proprietors of the "Universal Telephone Company," Electrical Engineers, and
GEORGE LEE ANDERS, Electrician, both of No. 11, Queen Victoria Street, in the
City of London, do hereby declare the nature of this invention to be as follows:-
The object of this invention is to render it practicable for a subscriber to a
telephonic or telegraphic system to be automatically switched on to or put in
communication with a receiver at some other point of the system at and for
predetermined times or periods.
In carrying the invention into effect, a clock or other piece of mechanism
equivalent thereto in respect of possessing a regular rotating motion, is placed at
cach end of the trunk line or at the junctions of the respective branch lines with
the said trunk line.
Each clock is provided with a suitable commutator, and both clocks with their
commutators are synchronized. The commutators are of a sufficient size to effect
at and for the respectively predetermined times, the respective connections between
one or several pairs of branch lines and the trunk line; and their teeth are set out
accordingly. The operation of the above described pair of clocks and commutators
is as follows. Assuming that there are 12 subscribers, all having city offices, their
city offices connected for periods of half an hour each with their respective
manufactories in the suburbs. A will be put on to his works and his works on to
his office at say 10 a.m., and cut off at 10.30, at which moment B's office and his
works will be placed in communication. The times and periods are, of course,
matters for pre-arrangement according to respective requirements or mutual
conveniences.
With the invention above described, a central office or manual switchboard is not
required, and each subscriber has, during his period, a line absolutely private to
himself.
Any suitable magnetic device may be applied to minimise the friction of the
moving parts of the clocks.
Our invention can of course be used in conjunction with any telephonic or
telegraphic system.
Dated this 13th day of October 1891.
PHILLIPS & LEIGH,
Agents for the Applicants.
COMPLETE SPECIFICATION.
Automatic Time Switch for Trunk Lines.
We. PERCIVAL PHILIP KIPPING, formerly trading as P. P. Kipping & Co.,
proprietors of the "Universal Telephone Company," at No. 11, Queen Victoria
Street, and GEORGE LEE ANDERS, of No. 10, Jeffrey's Square, St. Mary Axe, both
in the City of London, Electrical Engineers, 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 invention consists in a novel combination with a trunk line of time indicating,
or other regularly rotating, mechanism and a series of electrical contacts, such
combination of mechanism and contacts constituting an automatic time switch for
the connections between it and its branches.

page_text: The object of it is to render it practicable for a subscriber to a telephonic
telegraphic system to be automatically switched on to or put in communication
with a receiver at some other point of the system, at and for a predetermined time.
Our invention dispenses with a central office and manual switch boards, inasmuch
as it obviates the necessity of either of them, because the switching is automatic at
both ends of the trunk line. That being so, the latter and the branches are as
independent of outside adjustment as they are safeguarded against outside inter-
ference. This present invention is particularly applicable to costly or long distance
trunk lines through which private communication is desired.
The
The substance of our invention is as follows. A clock, or other piece of
mechanism equivalent thereto in respect of possessing a regular rotary motion, is
placed at each, or at one end of the trunk line, that is to say, at the junctions
of the respective branches therewith, and consequently beyond the control of any
subscriber or renter. Each clock is provided with a suitable commutator, and
both clocks and commutators are synchronized. This combination of clock and
commutator is what is hereinafter referred to as an automatic time switch.
commutators are of a sufficient size and proper type to switch on, at a predeter-
mined time, the two branch lines which constitute a pair; to keep them on for
a predetermined term; to switch them off at the end of that term, and to switch
another pair on. For example, suppose there are seven renters, each having an
office in the city and a works in the same suburban district. It has been agreed
amongst the renters that each shall have a turn of half an hour, and the order
in which the turns are enjoyed is also predetermined. A's office and works are
switched on to the trunk line at say 10.0 in the morning. From 10.0 to 10.30
A has a monopoly of the trunk line as much as if it were his private wire. At
10.30 he is switched off the trunk line-hoth office and works-and B's office and
works are switched on. Each renter will, therefore, have two turns of half an
hour each in the seven hours, with an interval of three hours and a half between
them. When once the number of renters and the times and durations of their
turns are settled, the commutators are set out accordingly. There is no obligation
imposed upon the renters to take their turns immediately after each other, nor
for all the turns to be of the same length. The commutator may be set for turns
of equal or unequal lengths, as well as for portions of time for which there are not
any renters.
The application of the invention is not confined to establishing turns for the day
only. In the example given above, the series of turns begins again at 5.0 p.m., at
which time the set of seven renters above mentioned may, as a set, be switched out
of the installation altogether and put beyond the control of their own clocks until
10.0 the next morning, a second set of renters, as a set, being automatically
introduced into the installation. This set might be newspaper editors or publishers
and their correspondents or agents, and their user of the installation be from 5.0 p.m.
to 4.0 a.m. A third set-e.g., retail purveyors and the salesmen at the large
markets might take the place of the second set at 4.0 a.m. and enjoy turns up to
10.0 a.m., when they would be switched off and the first mentioned set be switched
into the installation again. The devices by which one set of renters is, as a set,
switched out of the installation and a second one introduced, is of the same type
and construction as the automatic time switches described above, and is hereinafter
referred to as a master automatic time switch.
In order that the invention and the means by which it may be carried into effect,
may be thoroughly understood, we will now describe them in detail, referring in
so doing to the accompanying drawings which are to be taken as part of this
Specification and read therewith. It is however to be distinctly understood that our
invention is not confined, in respect of constructional details, to those shewn, for
they may be varied to any extent, provided that the discharge of the several
functions set forth in the preceding paragraphs is properly provided for.
Fig. 1 is a diagram of an installation embodying our invention as adapted to the
requirements of six renters using the trunk line from both termini.

page_text: Fig. 2 is a diagram of an installation embodying our invention as adapted to the
requirements of four renters situated at points along the trunk line instead of being
grouped about its termini.
Fig. 3 is a side elevation of a special commutator adapted to relieve the going
train of the respective clock of the strain due to the friction in the automatic time
switch illustrated in Figs. 1 and 2 between the minute hand and the commutator on
the clock face.
Fig. 4 is a plan corresponding with Fig. 3.
Fig. 5 is a diagram illustrating the synchronization of the clocks of an instal-
lation.
Referring to Fig. 1, a is the trunk line. b, are the two clocks, one at each
terminus of the line a. c, c¹ are two rings or annular contacts upon the respective
faces of the clocks b, b'. d, d' are studs upon the undersides of the minute hands e, e¹,
in constant electric contact with the respective rings c, c'. It is the minute hands
that are the contact arms of the commutators. 1, are studs upon the minute
hands on the same side of them as the studs d, d', and these studs are in electrical
contact with segments of which the commutator rings 9, 9' are composed. As a
matter of course, the rings c, c', the studs d, d, f, and minute hands e, e¹ are of
conducting material. h, i, j, k, land m are the renters' city offices and ¹, i, j, k², l'
and m' their respective works. The rings c, c¹ and the commutator rings 9, 91 are
insulated from their respective clock faces, and from the other members of their
respective trains. The trunk line is connected to the rings c, c; and the commutator
rings 9, 9', with the respective renter's branches s², s. We do not confine ourselves
in respect of the path of the current between the termini of the trunk line and the
respective minute hands. n, n' are the several and respective earths.
The commutators are duplicates of each other both as to division and position on
the dials, and the clocks are synchronized. Each commutator consists of as many
segments as there are renters, and the length of each segment is proportionate to
the length of the respective renters' turn. The segments are insulated from each
other, an insulation being sufficiently wide to prevent the stud on the minute hand
bridging or spanning it. Each renter's wires are connected to the respective
segments.
According to the commutators illustrated, each renter has a turn every hour,
because all the segments are controlled by the minute hand only, and all are cut
out of and switched into circuit once in each revolution of the said hand. We do
not confine ourselves to using a single commutator, but may use one of more than
one ring; neither does our invention confine us to the use of the minute hand only
as the contact make and break, for in a case when a turn is wanted for more than
an hour, that is for more than the time of one revolution of the minute hand, a
second ring is used and the hour hand adapted to act as a make and break on it,
the fraction of the turn being controlled by the minute hand in the manner already
described.
Referring to Fig. 2, the principle of the installation illustrated herein is the
same as that of the one illustrated in Fig. 1 and already described. a is the trunk
line and a' is a metallic return line, instead of having recourse to the earth. O, P,
Q, R are the offices of the four renters. They are all connected with the trunk
line at points between its termini. The agreement between the renters in the case
under specification is that P and R on the one hand, and O and Q on the other,
shall have a monopoly of the trunk line alternately for turns of 5 minutes each.
o, p, q, rare four clocks. o, p², q', r, s, and t' are the respective contacts or
seginents on the clock faces and they constitute the respective commutators. The
minute hands e are the contact makers and breakers. The rings c are connected
with the trunk line a; and the contacts o¹, p', q¹, r', s' and t' with the respective
renters, by as many branches, on the same principle as illustrated in Fig. 1. At
8.0, O and Q are switched off the trunk line and P and R are switched on to it and
each other. At 8.5 they are switched off and O and Q are switched on and to
each other, and so on,

page_text: It must be distinctly understood, that in place of the earth for carrying the
return currents (as in Fig. 1), we may use a metallic return.
Referring to Figs. 3 and 4, u is an electro magnet; and u', its circuit through
which an intermittent current is sent once a minute. This intermittency may be
effected in any convenient way. We propose to effect it by leading the current through
a rotating make and break t* controlled by the seconds arbour of a clock at each
end of the trunk line. The armature u² is carried on one arm of a bell crank
lever having its axis on a shaft ut. The other arm carries on its opposite end a
pivotted finger u³. vis a ratchet wheel. The finger is kept in engagement with
the wheel by a spring. This spring also serves to withdraw the armature from
the magnet after the current has ceased to flow through it. As the wheel v has
60 teeth and the armature makes minute beats, the said wheel is revolved once an
hour. In so far, it is the equivalent of the cannon pinion of a clock motion work.
20 is a second ratchet wheel. It is revolved once in 12 hours by the wheel through
any suitable mechanism, advantageously by that illustrated. is a double cam
fast on the shaft of the wheel . The two drops of it are both in the same plane.
w is a lever having its fulcrum on a fixed stud . It is kept in contact with the
periphery of the cam by a spring w. w is a finger pivotted upon the lever and
kept in engagement with the wheel w by a spring to. The wheel w has 24 teeth
because, as the cam v is a double one, the finger to makes two motions an hour. It
is, therefore, the equivalent of the hour wheel of a clock motion work, revolving
once in 12 hours. and we are pawls to prevent the respective ratchet wheels
rebounding.
The shafts of the above described mechanism have their bearings in two
plates, which are held parallel with each other at a proper distance apart by
distance pieces 1. a, are two insulations. y are twelve segments of equal size
insulated from each other. Together they constitute a 5 minute commutator, that is,
one giving turns of 5 minutes duration each. They are fixed (e.g., by screws z³) in a
circle upon one of the insulations a.. The renters' branches y are connected to
these segments as may be required. Fig. 3 shews 12 branches, each connected to
its respective segment. There may, therefore. be 12 renters, each enjoying a
5 minute turn, but not necessarily so, for one may be connected to more than one
segment, in which case his turn would be 5 minuted x the number of segments to
which his branch is connected. y² is a spring contact always in touch with one of
the segments y.
It is carried by an arm y fast on the end of the shaft 2. This
arm carries a small pin y' at its outer end against which the spring contact bears,
being steadied thereby. is a stationary spring contact.
One end of it bears
against the end of the shaft while the other is connected to the trunk line a.
,, are 12 seginents of equal size. They are fixed upon the respective insulation
and insulated from each other. Together they constitute an hour commutator, that
is one giving turns of an hour's duration each. 2, 2 are the branch wires to the
renters. As there are 12 segments, there may be as many renters, each enjoying a
turn of an hour. There are seven branch wires, four of them connected to as
many segments, one of them to 2, and two to 3 segments, that is to say, Fig. 3
illustrates the connections for 19 renters, 12 of whom are restricted to turns of five
minutes each, 4 to turns of an hour each, 1 to a turn of two, and 2 to a turn of
three hours. is a spring contact always in touch with one of the segments z.
It
is carried by ³, an arm fast on the end of the shaft w³ of the hour ratchet. 2º is a
stationary spring contact of the same type as the one y already described. The
connections between these two stationary spring contacts y, 2 and the trunk line a
may be as illustrated or of any convenient type. The shafts ², w³ are insulated
from the plates as far as may be necessary.
It is of course impossible for the twelve 5-minute renters-those on the brauch
wires y to use the trunk at the same time that it is open to any of the hour renters-
those on the branches '. We have shewn the 24 segments distributed among more
than 12 renters in order to illustrate more clearly the great variability of the duration
of the turns which characterises an insulation according to our invention. But the

page_text: two sets of segments y and z may be coupled when a turn of more than an hour but
of less than two is to be provided for. We will suppose that the turn in question is
2 hours. Two segments are joined together by themselves and the first three
y segments together by themselves, and the two groups to separate branches which
latter are then united and led to the renter. This arrangement is represented by
the dotted lines of Fig. 3. The remaining three quarters of the third hour are
utilise by branches from the y segments.
With reference to the commutators described above and illustrated in the
drawings, we have to point out that they may be made in several ways. For
instance, instead of mounting the segments in a circle tipon an insulation, we may
use a series of metal disc mounted upon an insulated revolving shaft and insulated
froin each other. The branches bear upon the peripheries, respectively, of the
discs, and each disc is electrically connected with the trunk line. The peripheries
are notched, and when a notch is opposite a branch, there is no contact. Such a
commutator is set out by differentiating the lengths of the notches and setting them
in echelon, so to speak, so that contact on one is made at the moment when it was
broken on the next. Discs of non-conducting material may have conducting segments
let into them, so that their exposed surfaces shall be within reach of the respective
branches, their inner ends being respectively in contact with, or connected to, the
trunk line.
Figure 5 is a diagram illustrating the synchronization of the two clocks of an
installation. , b' are the two clocks. The current used for the purpose of effecting
the synchronization, as well as the conductor for it, may be specially provided, or
we may use the current with which the installation is worked and its trunk line.
The diagram illustrates the use of a special current and conductor.
1 is the battery; 2, its earth; 3, the conductor from the battery to 4 a contact
on the dial of the synchronizing clock b. This contact coincides with the 12.0 point,
and stands in the path of the minute hand. 5 is a contact on the back of the
minute hand, and 6, a contact on the clock dial. The contact 6 stands between the
centre of the dial and the 12.0 point. The 7, 8 and 9 are contacts on the clock 6¹
corresponding with 6, 5 and 4, respectively, with this exception that the contact 9
is long enough to cover the possible variations of its clock. 10 is a conductor from
the contact 9 to an electro magnet 11, and 12 its conductor to 13, its earth. The
armature 14 is pivotted at 15, and an extension of it carries a V 16 which stands
over a disc 17 fast to the minute hand and in which there is a V shaped notch in
its periphery. This disc is aligned with or fast to, the minute hand. 18 is the
conductor from the hour hand of one clock to that of the other. The clock b¹ is
synchronized as follows. As 12.0 approaches, the minute hand of the clock 6' makes
contact with the contact 9. At 12.0, the minute hand of the clock 6 closes the
circuit, and the energized magnet attracts its armature, thereby pulling the V 15
down the notch in the disc 16, and rocking the minute hand to which the said disc
is fast, forward or backward, as the case may be. As soon as 12.0 is passed, the
minute hand of the clock b breaks contact, and the armature is free. The rotating
notch pushes the V out of it on to the periphery of the disc.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner it is to be performed, we claim:
1. The combination of a trunk line, one automatic time switch (being a clock or
other regularly rotating mechanism provided with a commutator), and branches, as
and for the purpose set forth.
2. The combination of a trunk line, an automatic time switch at each end and a
set of branches appropriated to each switch, as and for the purpose set forth.
3. The combination of a trunk line, a commutator having its segments at each
end of the trunk line set out according to the duration of the several renters' turns,
contact arms of both commutators moving together and being in contact with the
segments appropriated to any renter at and during the same time, while they are

page_text: both always in electrical contact with the trunk line, and branches from the
segments of both commutators to the respective renters.
4. The combination of clock movement or other regularly rotating movement,
hands or arms adapted to discharge the functions of makes and breaks, segments
arranged in a circle according to the renters' turns, a single trunk line and a pair of
branches for renter.
5. The combination of trunk line, two sets of branch lines, commutators adapted
to control the electrical connections between the said trunk line and one pair of
branch lines at a time, and clocks adapted to shew the time, to provide the makes
and breaks and to be synchronized by the current.
6. The combination with an installation comprising a trunk line, automatic time
switches and branches at each end, of master automatic time switches adapted to
cut out one set of renters and to introduce another into the said installation.
7. The combination with a trunk line and at either or both ends thereof of an
electro magnetic device, and a clock adapted to automatically energise it at regular
periods, as set forth.
Dated this 13th day of July 1892
PHILLIPS & LEIGH,
No. 22, Southampton Buildings, Chancery Lane, W.C.,
Agents for the Applicants.