An Improved Electric Switch.
Year: 1899

page_text: PROVISIONAL DERUTTUALION
An Improved Electric Switch.
I, WALTER JOHN MURPHY, of 39, Courtfield Gardens, Earls Court, London,
Cable Engineer and Electrician, do hereby declare the nature of this invention
to be as follows:-
This invention relates to an improved electric switch and has for its object
to construct a switch by means of which those lights in an installation not
required to be kept in circuit for the same period as others, may be thrown out
of circuit from the main switch of the installation without affecting the rest of
the said lamps, and which at the same time may be used independently in the
ordinary manner as an on and off switch, and also to construct the said switch
in such a manner as to effectually prevent any tampering with the switch tending
to prevent its acting in the manner above described.
The switch in its simplest form may consist of a suitable base having a metal
Jug secured thereto to which is pivotally attached a metal bar to which is con-
nected one lead of the circuit, and normally held out of contact by means of a
suitable spring. The bar may be depressed by any suitable means, say a centrally
pivotted lever, the outer end of which projects through the outer case and is
operated by hand in the usual manner, the inner end coming into contact with
and depressing the bar aforesaid causing it to make contact and complete the
lamp circuit either by forcing it between two springs fixed to the base board
to which is attached the other lead, or any other suitable contact may be employed.
The end of the lever aforesaid has formed in it a recess into which falls a dog
or tooth formed at one end of a spring governed lever or pawl, one end of which
lies in the field of an electro-magnet energised directly by the current in the
lamp or lamps circuit, so that if the main switch be " flicked" whilst the lamp
governed by the second switch is in circuit, the magnet will be demagnetised
and the dog withdrawn from its engagement with the end of the bar, which
under the action of its spring breaks contact, cutting out the lamp or lamps as
the case may be, from the circuit.
001
1000
J. E. EVANS-JACKSON & Co.,
Agents for the Applicant.

page_text: 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 invention relates to an improved electric switch and has for its object to
construct a switch by means of which those lights in an installation not required
to be kept in circuit for the same period as others, may be thrown out of circuit
from the main switch or a controlling switch of the installation without affecting
the rest of the said lamps and which at the same time may be caused to operate
independently of the main switch, and further to construct the switch in such a
manner as to prevent any tampering with the switch to prevent its being operated
as above described.
In the accompanying drawings illustrating the invention
Fig. 1 is a front view of a switch with outer cover removed.
Fig. 2 is a side elevation.
Fig. 3 is a separate view of a detail thereof.
Fig. 4 is a side sectional elevation of the switch lever.
Fig. 5 is a side view showing the retaining magnet.
Fig. 6 is a side view of the parts shown occupying the position they would
assume when the circuit is being closed by hand.
Fig. is a front view of an alternative form of switch designed to prevent
tampering which would prevent its being operated by the main or controlling
switch.
Fig. 8 is a side elevational view thereof certain parts however being omitted
for the sake of clearness.
Fig. 9 is a side view of a detail of same.
Fig. 10 is a side view of a spring actuated plate forming part of the switch.
Fig. 11 is a view showing a modified form of the switch designed to be used
in a system when an alternating current is employed.
Fig. 12 shows a modified form of switch as illustrated by Fig. 11.
Referring to the drawings it will be seen that the switch consists of a suitable
base having an opening formed therein for the reception of the electro
magnet 2 carried by the plate 3, to which it is secured by the screwed end 4
of the magnet pole, the plate itself being attached to the back of the base 1 by
means of the screw 5 passing from the front thereof to the said plate into which
it is tapped as indicated in Figs. 1 & 2. The outer end of the pole of the magnet
is preferably flush with the surface of the base I and has situated on either side
of it contact blocks or pieces 6 and 7 one of which 6 forms the terminal for the
lead, and to the other is secured one end of the wire upon the magnet as indi-
cated in dotted lines Fig. 1. The other end of the wire upon the magnet is
secured to the terminal 8 to which the other lead is attached. Pivotally secured
to the block 9 (which block is held in position by the screw 10 passing through
the plate 3 base 1 and tapped into the block) is a tumbler 11 consisting of two
side plates 12 which may be formed of sheet iron or other metal, shaped as shown
with an arm 18 projecting at an angle from the plates 12. The two plates are
joined together by the transverse plate 14 of brass or other non-magnetic material
and which plate is cut away for the purpose hereafter described as shown
at 15. Fig. 3. The plates 12 are shown with a bend outwards at their upper
ends the distance between the inner faces of the contact blocks 6 and 7 being
such that when the said plates are brought into vertical position or parallel with
the surface of the base 1 a good contact shall be formed between the plates and
the blocks 6 and 7 completing the circuit and energising the magnet.
Also pivotted to the block 9 is a lever 15 formed of sheet metal preferably
soft iron to ensure a close magnetic circuit when switch is closed and of an
approximately U shaped section the base or back portion however being flat:
to further attain this object the screw 10 and block 9 are also of soft iron.
The lever has secured to it a transverse pin 16 to which is attached one end
of the spring 17 secured at its opposite end to the stud 18 carried by the base 1.

page_text: The lever 15 is located between the plates 12 and is provided with a suitable
handle 19 which projects through the outer case to allow of the switch being
operated by hand. The position of the parts is normally that indicated in Figs.
and 2, the return movement of the handle 19 being effected by the spring 17
and the amount of such movement governed by the length of the slot in the
outer, case through which such handle projects. Secured to the ends of the
arms 13 is a transverse bar 20 against which, when the magnet is demagnetised,
the lever strikes, carrying the same with it upon its upward movement which,
as aforesaid, is effected by the spring 17. The action of the switch is as
follows: When it is desired to throw the lamp or the lamps governed by the
switch into circuit, the handle 19 is caused to assume a position more or less
parallel to the surface of the base 1 thereby bringing the back of the lever 15
into contact with the plate 14 causing the side plates 12 of the tumbler to make
contact with the blocks 6 and 7 and energising the magnet 2. the soft iron lever
then being within the range of the magnets field is attracted thereby and held in
the position shown in Fig. 6, the lever being prevented from actually coming
into contact with the pole of the magnet by the plate 14 aforesaid. If now the
main switch be "flicked" the magnet will be momentarily demagnetized and
the spring 17 acting upon the lever 15 will cause it to rise striking against the
cross bar 20 as indicated in Fig. 5, and carrying the tumbler 11 with it until
the parts are restored to their original position. It will be obvious from the
foregoing description that the lamps may be thrown out of circuit by moving
the lever by hand irrespective of the main switch.
In some cases it may be found advantageous to construct the switch in such
a manner that when once it has been operated to throw the lamp or lamps into
circuit it cannot easily be fixed by jamming the lever or otherwise so as to prevent
its operating properly when the main or controlling switch is "flicked" or it
cannot be again operated until after it has been released by the main switch as
aforesaid. In these cases I dispense with the handle 19 and instead I actuate
the lever 15 by means of the S shaped cam or plate 21 which, as shown in
Figs. 7 and 8 is mounted upon the spindle 22 carried by the extensions or
arms 23 24 which may be formed integral with or secured in any suitable man-
ner to the contact blocks 6 and 7. It will be seen on reference to the drawings
that the S shaped plate 21 is so situated and of such dimensions as to engage with
the front plate of the lever 15 Fig. 2, and upon the revolution of the spindle to
which it is secured to press the lever inwards towards the magnet making con-
tact precisely as in the preceding case. The movement of the spindle 22 is
effected by means of the arm 25 freely pivotted at its lower end upon said spindle
and provided at its upper end with a handle projecting through the outer case
and by which the said arm is caused to rotate through an arc of a circle the
extent of which wouid be limited by the length of the opening in the outer case
shown broken away in Fig. 7 and dotted in Fig. 8. Upon the
inside of the arm 25 and secured to the spindle is a disc 26 upon the
periphery of which are formed two or more recesses or notches 27 with which
engages a spring pawl 28 transmitting the movement of the arm to the disc.
At the opposite end of the spindle 22 is secured a plate 29 approximately oval
in outline and against the periphery of which bear the springs 30 shown sup-
ported by the L shaped bracket or support 31 secured by screws or equivalent
means to the base of the switch. The plate 29 is so disposed relatively to the
plate 21 that upon rotating the spindle 22 the springs 30 will tend to impart
a partial rotary motion to the plate as soon as 15 is attracted by the magnet
which will thereon rotate, the plate 21 rotating with it and thus carried round
from and placed in such a position as to be out of contact with 15 until the latter
is again released by the magnet. The switch may be caused to break the circuit
by either of the three following means:-
1. By the main or controlling switch as herein before described.
2. By a press button which will electrically short circuit the retaining maơ-

page_text: net and thereby release the lever 15 which under the action of its controlling
spring will be caused to fall back and break the circuit.
3. A special lever (not shown upon the drawings) may be provided to force
15 out of contact.
In cases where it is required to employ such a switch as that forming the
subject of the present application for alternating currents I may instead of the
form of switch illustrated in Figs. 1-10 employ the form illustrated in
the diagrammatic view Fig. 11 in which the lever 15 instead of being retained
directly by the attraction of an electro magnet is held by means of the dog or
tooth 32 which when the lever is caused to close the circuit as in the preceding
cases, engages with a recess formed in the end of the said lever. The tooth 32
aforesaid is formed at the end of the pivotted arm 33, which arm is normally
retained in a position to permit of the tooth engaging with the recess upon the
lever 15 by means of a spring 34. The arm 33 is actuated by the magnet 35
energised by a third wire which may be arranged as shown in Fig. 11 electricity
being obtained by means of the battery 36. The ends of the wire may have an
earth return and the switch or the like 37 may be placed either one side or the
other of the source of electricity actuating the magnet as may be found most
suitable. This arrangement may also be employed when it is required to operate
the switch from a distance. It is obvious also that the last described arrange-
ment may be employed for ordinary use in which case I may arrange it as shown
in Fig. 12, in which a magnet included in the main circuit actuates an arm
or lever pivotted at c and having at one end a tooth d engaging with a recess 2
formed in the end of the lever 15 the circuit being closed in the manner
described in connection with the first forms of switch. It will be seen from
the drawings that in this case the arm is normally held by the spring b₁ so
that the tooth thereon does not engage with the end of the lever 15 until the
circuit is closed and the magnet energised when the arm will be attracted by
the magnet and held so long as the current flows.
I may instead of the magnets herein described and illustrated, employ as a
means for retaining the catch, (holding the contact arm in position when switch
is on), employ either an arrangement of double solenoids or an arrangement of
electrostatic discs, quadrants, or cells these latter alternatives being used in cases
where it is desired to reduce the power requisite to operate the switch to a
minimum.
It will be evident from the foregoing description that I may vary the general
arrangement of some or all of the forms of switches herein described without
departing from the principle of the invention, and further, that although I have
described a preferred form or forms of switch or switches for use upon an alter-
nating circuit that any of the forms shewn and described may be adapted to act
under an alternating current by employing suitably wound magnets or equiva-
lent means.
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 a switch of the kind herein described the combination with a suitable
electro magnet of a mechanically actuated lever 15 a tumbler 12 coacting with
the lever 15 to close the circuit by making contact with the two contacts 67
whereby the said magnet is energised and the circuit kept closed until the cur-
rent momentarily ceases to flow substantially as herein described and illustrated
by the appended drawings.
2. In a switch of the kind herein described the combination with a suitable
electro magnét of a lever 15 a tumbler 12 and a plate 21 shaped as shown and
mounted upon a spindle 22 capable of being rotated by means of the handle
and slotted disc 26 an oval plate 29 also attached to the spindle 22 having springs

page_text: so bearing against the periphery thereof the whole acting and arranged substan-
tially as herein set forth and shown by the appended drawings.
3. In a switch of the kind herein described the combination with the contact
tumbler and lever of a pivotted arm or lever 33 provided with a tooth or pro-
jection 32 engaging with a recess formed in the end of the contact tumbler and
actuated against a spring 34 by an electro-magnet energised from an external
source substantially as herein described and shown by the appended drawings.
4. In a switch of the kind herein described the combination with the contact
tumbler and its actuating-lever of a pivotted arm having a tooth enagaging
with a recess formed in the end of the contact tumbler and actuated against a
spring 6 by an electro magnet energised by the main current substantially as
herein described and illustrated by the appended drawings.
5. A switch capable of being actuated from the main or controlling switch by
momentarily causing a cessation of the flow of electricity whereby the switch
is caused to automatically break the circuit.
6. A switch of the kind herein described so constructed and arranged as to
prevent any tampering or interference therewith to impede its free action sub-
stantially as herein described and illustrated by the appended drawings.
Dated this 11th love of Navambar 1800
J. E. EVANS-JACKSON & Co.,
Agents for the Applicant.