Improvements in Electric Cut-outs.
Year: 1889

page_text: Date of Application, 12th Apr., 1889
Complete Specification Left, 14th May, 1889-Accepted, 22nd June, 1889
PROVISIONAL SPECIFICATION.
Improvements in Electric Cut-outs.
I HERBERT NAPIER PRENTICE of 185 Princes Street Ipswich in the County
of Suffolk Electrician do hereby declare the nature of this Invention to be as
follows:-
.
The object of my Invention is to provide a cut out for electric circuits which is
simple in construction and very efficient and certain in action.
The Invention relates to the class of cut outs which are operated by magnetic
attraction due to an abnormal condition of the current in the circuit.
According to my Invention I cause the armature which is attracted by the core
of the magnet wound with wire included in or taken as a shunt from the circuit to
be governed to actuate a tumbler or kicker so that the said tumbler or kicker being
overbalanced falls over and acts on the bridge or contact makers to quickly and
with certainty remove them from the mercury cups or contacts.
The kicker or tumbler or some part operated when the circuit is broken I prefer
to arrange as annunciator to clearly indicate to the attendant that the breaking of
the circuit has taken place.
Thind this 19th doe of Anvil 1000
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in Electric Out-outs.
I HERBERT NAPIER PRENTICE of 185 Princes Street Ipswich in the County of
Suffolk Electrician 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 object of my Invention is to provide a cut-out for electric circuits which is
simple in construction and very efficient and certain in action.
The Invention relates to the class of cut-outs which are operated by magnetic
attraction due to an abnormal condition of the current in the circuit to be
controlled.
According to my Invention I cause the armature which is attracted by the magnetic
coil or core wound with wire included in or taken as a shunt from the circuit to be
governed to actuate a tumbler or kicker so that the said tumbler or kicker being
overbalanced or released falls and acts on the bridge or contact makers to quickly
and with certainty remove it or them from the mercury cups or contacts. The
kicker or tumbler or some part operated when the circuit is broken I prefer to arrange
as an annunciator to clearly indicate to the attendant that the breaking of the circuit
has taken place.
And in order that my said Invention may be fully understood 1 shall now proceed
to describe the best means with which I am acquainted for carrying it into effect,
and for that purpose shall refer to the annexed drawings.
Figure 1 is a side view and Figure 2 is a front view of a cut-out constructed or
arranged according to my Invention shewing the parts in the positions they occupy
when the circuit is complete. Figure 3 is a side view shewing the parts in the
position which they assume when the circuit is broken. A. is the core of the electro
magnet wound with wire included in, or taken as a shunt from the circuit to be
controlled being the sockets or binding screws by which the external wires are
secured. The said sockets or screws are on conducting pieces B. B³ the piece B*

page_text: heing electrically connected to the conducting piece B³ carrying the mercury cup C
and the piece B being in electrical connection through the coil of the electro magnet
with the conducting piece B carrying the mercury cup C. Into the cups C C dip
the ends d of the bridge piece D provided with arms centered by the pine to the
bracket f. On this pin e are also centered the arms g. carrying the armature g² the
said arms being connected by the cross piece o extending behind the lever H also
centered on the pine and having a counterbalance weight at h and a tail piece h*
constituting a kicker. I is a screw in the bracket by means of which the position
of the armature g³ relatively to the end of the magnet core A. can be adjusted.. The
parts are mounted on a support or base ✗ of insulating material.
When the current is in the proper normal condition the parts remain in the position
shewn in Figures 1 and 2 but on the current increasing to such an abnormal extent
as to cause the electro magnet to attract the armature g³ the crosspiece g' moves the
lever H into such a position that its weighted head / causes it to suddenly fall over so
that its tail end h kicks the bridge and knocks it over into the position shewn in
Figure 3 quickly removing the contacts d from out of the mercury cups and breaking
the circuit. The inner part of the lever H may be coloured red or otherwise
coloured or marked so as to act as a readily observable annunciator of the breaking
of the circuit.
When the apparatus is used for continuous currents I prefer to use a core to the
magnet as shewn but when the apparatus is used for alternating currents I prefer to
dispense with the core or to use a core made up of insulated iron wires or plates.
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 1
claim is :-
1. In an electrical cut-out operated by magnetic attraction due to an abnormal
condition of the current in the circuit to be controlled, a tumbler or kicker arranged
so that on an abnormal condition of the current occuring the said tumbler or kicker
is caused to fall and affect the removal of the contacts to break the circuit substantially
in the manner hereinbefore described.
2. The arrangement and combination of parts constituting the electric cut-out
substantially as hereinbefore described and illustrated in the accompanying drawings.
Dated this 14th day of May 1889.