Year: 1886

page_text: Date of Application, 2nd Dec., 1886
Complete Left, 2nd Sept., 1887
Complete Accepted, 2nd Dec., 1887
I ISAAC PROBERT of 88 Penrose Street Walworth Road in the County of Surrey
Electrical Engineer do hereby declare the nature of this invention to be as
follows:-
:-
My Invention relates to improvements upon the apparatus described in the Speci-
fication to my patent application numbered 2691 of the year 1886 and comprises
modifications which widen its range of usefulness in certain applications of
electricity.
.
The apparatus there described consists of a boss of insulating material with two
conducting segments attached thereto and these segments each extend nearly half
round the boss so that the extremities of the segments are not far apart.
Around the boss there is a ring also of insulating material and one or two small
pieces of metal are let into this ring so as to fit closely to the segment or segments.
When the ring is turned so that the piece or pieces is or are in contact each with the
two segments attached to the boss the circuit is complete and when the ring is turned
so that this is no longer the case the circuit is open.
Now instead of completing the electric circuit by causing the electrical contact
piece or pieces on the inside of the insulator ring to electrically connect the metal
segments which are on the insulator boss, I sometimes employ curved springs and
join one end of each spring to its respective segment on the boss leaving the other
end of each spring free above and out of electrical contact with the end of the opposite
segment. This is the position when the electric circuit is incomplete, but on moving
the ring through a suitable distance projections on the inside surface of the ring
depress the free ends of the curved springs until electrical contact is established
between the segments. One curved spring only may be employed.
The free ends of the curved springs are usually inclined planes and against these
the projections on the ring act in switching "on." When switching "off" the spring
or springs quickly and forcibly return the ring to its extreme "off" position. As an

page_text: easy means of switching a current " or "off" I provide "knobs" or
on
"handles"
or milled projections on the outer circumference of the insulator ring. To facilitate a
good rubbing contact I occasionally fix a short curved spring on that part of each
segment which is just below the inclined plane before mentioned and to effect the same
object I sometimes make that same part of each segment springy instead of employing
short curved springs as described above.
*
In other cases I flatten one end of each segment and solder or otherwise attach a
bit of platinum foil thereto and also furnish the contact surfaces above with a portion
of the same inoxidizable metal.
Another improvement I have effected is to combine with my switch a
safety fuse
chamber" consisting of a recess in the bottom part of my switch and a somewhat
similar recess made in a separate piece of non conducting material. The wall part of
the switch recess is either partly or wholly covered with metal, and the separate piece
alluded to above possesses either a complete metal ring or two distinct segments of
metal. When the wall of the switch recess is surrounded by a metal ring and the
separate piece bears a ring also, then one leading wire is joined to the latter ring,
and the other leading wire (after passing through a hole in the combination arrange-
ment) is joined to one of the two lamp connections; but if both recesses be furnished
with divided metal rings, then each leading wire is put into contact with one metal
segment on the separate piece. When the switch part is pressed upon the separate
piece (like putting the lid on a small circular box) a chamber is formed the metal
pieces are thereby brought into contact and constitute part of the electric circuit.
Electric communication between the switch recess and separate piece is also
obtained by me in another way namely by fixing an annular metal ring on the bottom
of the switch recess and a corresponding annular metal ring on the shoulder of the
"separate piece" in such a manner that when the switch recess is screwed to the
separate piece" electrical contact is made between the two parts.
66
The chamber containing the fuzed wire is lined with non-combustible material, and
projections in the switch recess usually fit into corresponding slots in the ring of the
separate piece to obviate any turning motion when the switch is put on" and "off."
The electrical connections of my combination are in most cases such that should the
fuse wire in the chamber be destroyed, the switch can be readily pulled off,
unscrewed or otherwise detached from the "separate piece" (so called) and taken to
any convenient place for renewal of the fuse wire, without removing any of the circuit
wires.
A further improvement is (1) to fix on the insulator boss, one or two "double
segments" that is to say, one or two spring clips, of any required dimensions, and at
a suitable distance apart, (2) to place on the inside of the insulator ring corresponding
curved tongues or springs so that when the ring is turned to switch " on an electric
current the free end of each tongue is driven between the corresponding double segment
or spring clip, (3) to make a suitable groove in the bottom surface of the insulator ring
which shall contain a flat metallic spring having one end secured to the ring itself or
contact tongue, and the other end secured to a pin erected on the shoulder immediately
below the ring. This spring and pin may or may not form part of the electric circuit.
On making the electric circuit the curvature of the spring is increased and on breaking
the circuit the spring pulls the ring back again to its norinal position of "no current."
Sometimes I coil a similar spring in a suitable cavity made in the insulator boss, and
I so secure its extremities that an effect upon the ring like that described above is
produced.
The shoulder over which the insulator ring works has in some instances a
ring turned
thereon, and a corresponding groove in the bottom of the insulator ring encloses it.
The object is to furnish a guide for the insulator ring and also to diminish friction.
This form of my switch can be made to (1) close or open the electric circuit on one
wire only (2) to make or break the circuit with both wires simultaneously, (3) to
reverse the direction of current at pleasure and further (4) it can be made large
enough for any practical electric current. In case (3) I use a moveable plug, stop,
or other device for controlling the direction and extent of the insulator ring move-

page_text: ment and instead of one ring I sometimes prefer having two rings one above the
other arranged in such a manner that while one ring serves to reverse the direction of
the electric current at will, the other ring enables the current to be turned on or
off the circuit.
I frequently surround the insulator ring with a case or short cylinder having
suitable slots cut in it for the handles which enable a current to be switched on and
off. This cylinder supports a transparent plate which covers the top of the insulator
boss and permits the electrical contact action to be observed. The case and cover
also keep away dust and dirt from the contact pieces. I often make one or two wells
in the insulator boss and place therein suitable fuses " in connection with my switch
electrical connections. The transparent cover, which may be a hinged door or other-
wise enables anyone to see the condition of the fuse or fuses, and the whole arrangement
is as far as possible made a safeguard against fire.
Dated this 2nd day of December 1886.
CARPMAEL & Co.,
Agents for the Applicant.

page_text: I, ISAAC PROBERT of 88 Penrose Street Walworth Road in the County of Surrey
Electrical Engineer, 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 :—
My invention relates to improvements upon the apparatus described in the Speci-
fication of my Patent numbered 2691 of the year 1886 and comprises modifications
which widen its range of usefulness in certain applications of electricity.
The apparatus there described consists of a boss of insulating material with two
conducting segments attached thereto and these segments each extend nearly half
round the boss so that the extremities of the segments are not far apart.
Around the boss there is a ring also of insulating material and one or two small
pieces of metal are let into this ring so as to fit closely to the segment or segments.
When the ring is turned so that the piece or pieces is or are in contact each with the
two segments attached to the boss the circuit is complete and when the ring is turned
so that this is no longer the case the circuit is open.
Now instead of completing the electric circuit by causing the electrical contact
piece or pieces on the inside of the insulator ring to electrically connect the metal
segments which are on the insulator boss I sometimes employ curved springs and
join one end of each spring to its respective segment on the boss leaving the other
end of each spring free above and out of electrical contact with the end of the
opposite segment. This is the position when the electric circuit is incomplete, but on
moving the ring through a suitable distance projections on the inside surface of the
ring depress the free ends of the curved springs until electrical contact is established
between the segments. One curved spring only may be employed.
22
"
"
The free ends of the curved springs are usually inclined planes and against these
the projections on the ring act in switching
on. When switching "off" the spring
or springs quickly and forcibly return the ring to its extreme "off" position. As an
easy means of switching a current "on" or off" I provide "knobs ог handles
or milled projections on the outer circumference of the insulator ring. To facilitate
a good rubbing contact I occasionally fix a short curved spring on that part of each
segment which is just below the inclined plane before mentioned and to effect the
same object I sometimes make that same part of each segment springy instead of
employing short curved springs as described above.
In other cases I flatten one end of each segment and solder or otherwise attach a

page_text: bit of platinum foil thereto and also furnish the contact surfaces above with a portion
of the same inoxidizable metal.
It is moreover a common practice of mine to employ two metal spring segments
around the insulator boss which have one end fastened to the boss and the other end
overlapping the fixed end of the other segment but out of contact with it when the
switch is not in electric action, but when these free ends are depressed by the suitable
projections on the insulator ring both spring segments are electrically united.
I also adopt the plan of placing similar curved springs on the shoulder of the
insulator boss piece instead of encircling the boss either with such springs, or segments
having each end attached to the boss. The movements of the insulator ring either
open or close the circuit in the same manner as before stated.
Another improvement I have effected is to combine with my switch a "safety fuse
chamber" consisting of a recess in the bottom part of my switch and a somewhat
similar recess made in a separate piece of non conducting material.
The wall part of the switch recess is either partly or wholly covered with metal, and
the separate piece alluded to above possesses a either a complete metal ring or two
distinct segments of metal.
When the wall of the switch recess is surrounded by a metal ring and the "separate
piece" bears a ring also, then one leading wire is joined to the latter ring, and the
other leading wire (after passing through a hole in the combination arrangement) is
joined to one of the two lamp connections; but if both recesses be furnished with
divided metal rings, then each leading wire is put into contact with one metal segment
on the separate piece. When the switch part is pressed upon the separate piece (like
putting the lid on a small circular box) a chamber is formed the metal pieces are
thereby brought into contact and constitute part of the electric circuit.
communication between the switch recess and "separate piece" is also obtained by
me in another way namely by fixing an annular metal ring on the bottom of the
switch recess and a corresponding annular metal ring on the shoulder of the "separate
piece in such a manner that when the switch recess is screwed to the "separate
piece electrical contact is made between the two parts.
Electric
The chamber containing the fuze wire is either lined with non-combustible material
or is a non-combustible substance. Projections in the switch recess usually fit into
corresponding slots in the ring of the separate piece to obviate any turning motion
when the switch is put "on" and "off"-but these projections-which are often pins
or bolts frequently form parts of the electrical circuit of the combination arrange-
ment by entering metallic eyelets or other device in the recess of the "separate piece."
This is especially the case when the insulator substance used is china (porcelain) or
slate. The electrical connections of my combination are in most cases such that
should the fuse wire in the chamber be destroyed, the switch can be readily pulled off,
unscrewed or otherwise detached from the "separate piece" (so called) and taken to
any convenient place for renewal of the fuse wire without removing any of the circuit
wires.
A further improvement is (1) to fix on the insulator boss, one or more "double
segments that is to say, one or more spring clips, of any required dimensions, and
at a suitable distance apart, (2) to place on the inside of the insulator ring corre-
sponding curved tongues or springs so that when the ring is turned to switch " on
an electric current the free end of each tongue is driven between the corresponding
double segment or spring clip, (3) to make a suitable groove in the insulator ring
which shall contain a flat metallic spring having one end secured to the ring itself
or contact tongue, and the other end secured to a pin erected on the shoulder imme-
diately below the ring. This spring and pin may or may not form part of the electric
circuit. On making the electric circuit the curvature of the spring is increased and
on breaking the circuit the spring pulls the ring back again to its normal position of
no current."
Sometimes coil a similar spring in a suitable cavity made in the
insulator boss, and I so secure its extremities that an effect upon the ring like that
described above is produced.
«

page_text: diminish friction.
The shoulder over which the insulator ring works has in some instances a ring
turned thereon, and a corresponding groove in the bottom of the insulator ring
encloses it. The object is to furnish a guide for the insulator ring and also to
This form of my switch can be made to (1) close or open the
electric circuit on one wire only (2) to make or break the circuit with both wires
simultaneously, (3) to reverse the direction of current at pleasure and further (4) it
can be made large enough for any practical electric current. In case (3) I use a
moveable plug, stop, or other device for controlling the direction and extent of the
insulator ring movement; and instead of one ring I sometimes prefer having two
rings, one above the other arranged in such a manner that while one ring serves to
reverse the direction of the electric current at will, the other ring enables the current
to be turned on or off the circuit.
I frequently surround the insulator ring with a case or short cylinder having
suitable slots cut in it for the handles which enable a current to be switched on and
off. This cylinder supports a transparent plate which covers the top of the insulator
boss and permits the electrical contact action to be observed. The case and cover
also keep away dust and dirt from the contact pieces. I often make one or two wells
in the insulator boss and place therein suitable "fuses" in connection with my switch
electrical connections. The transparent cover, which may be a hinged door or other-
wise enables any one to see the condition of the fuse or fuses, and the whole arrange-
ment is as far as possible made a safeguard against fire.
In some of my large switches the insido of the insulator boss is removed to form a
ring, and within this ring is suitably arranged a magnetic device, or coil of wire,
which is so influenced by the current in the metallic segments or springs as to deflect
an index needle over a graduated dial plate thus serving to indicate the direction of
the electric current in the circuit or to measure the strength of that current.
In order that my invention may be fully understood I have in the drawings here-
unto annexed shewn examples of electrical switches and appliances constructed as
above described.
One form of electrical switch and safety fuse appliance is shewn at Figures 1 to 7.
Another form is shewn in Figures 8 to 13.
Figure 1 is a side elevation and Figure 2 a plan. Figure 3 is a vertical section
through the line 1, 1, and Figure 4 a vertical section taken through the line 3, 3.
Figure 5 is a cross section through the line 2, 2. Figure 6 is a plan view of the
lower part called the "separate piece" and Figure 7 is an underside view of the piece
which fits thereon and forms with it the fuze chamber.
In these figures A is the "separate piece" of non conducting material with a
screwed metallic bush passing through its centre to allow of its being screwed onto
any suitable support. B B are two metallic segments secured to the bottom of a
recess on the upper side of the piece A. One wire conductor is coupled as shewn by
the dotted lines in figure 4 to one segment, and the other wire conductor to the other
segment. C is the insulating piece carrying the switch and safety fuse. In its
under side there is a recess with two metallic segments D D secured to its sides to
fit over and be brought into electrical contact with the segments B B². The exterior of
the upper part of the piece C has secured to it two springs EE on opposite sides of
its circumference. The metallic segment D is coupled to one of these springs. The
other segment D' is electrically connected with a metallic segment L' which is one of
the electrical connections for the lamp. A safety fuse HL of thin fusible wire is
carried from the metallic segment G to a similar metallic segment G¹. If the piece C
is of ebonite or like combustible material then I interpose a piece of sheet asbestos
between the wire and the ebonite or combustible material. I is a ring surrounding
the upper part of the piece C-on its exterior it has two handles projecting from it
by which it can be turned. On its interior are two recesses to allow the free ends
of the springs E to spring outwards away from the piece C. The stems of the handles
of the ring project into these recesses and bear against the outer sides of the springs.
When the ring is in the position shewn in Figure 5 the free ends of the springs

page_text: are standing outwards from the piece but if a partial turn he given to the ring I
then the stems of the handles force the free ends of the springs inwards and either
bring the free end of the spring into contact with the fixed end of the other spring or
into contact with a metallic segment connected thereto so that complete electrical
contact is established between the two springs. K is an ordinary holder for an incan-
descent electric lamp-it screws on to a screw stem, which projects from the centre
of the top of the piece C. It has in it as usual two spring metallic segments LL
with which the conductors of the electric lamp are brought into contact. The metallic
segment is electrically connected with the metallic segment G and the metallic
segment is electrically connected with the metallic segment D¹. These electrical
connections are clearly indicated by the dotted lines in figure 4. Assuming the
current to enter by the conductor represented by the dotted line a it will pass to the
segment B and from it to the segment D and to one of the springs E-then if
the ring 1 has been turned into a position to bring the springs into contact with one
another the current passes to the second spring and from it to segment G and through
the safety fuse wire H to the segment G¹ from which it passes to the metallic
segment and through the lamp to the segment L' from which it passes by the
segments D'B' to the return conductor b.
It will be seen that with the above construction the piece which carries the safety
fuse can readily be separated from the piece A to which the electrical conductors
are connected, so that without interfering with the fixing of these electrical conductors
the safety fuse can be taken away should it have become injured and be quickly
replaced by another one.
*
When the wall of the switch chamber is surrounded by a metal ring and the
separate piece bears a ring also then the electrical connections are modified in the
manner indicated by the diagram view figure 4 A.
The switch and appliances connected therewith shewn at figures 8 to 13 is some-
what modified in construction to allow of the parts which are of insulating material
being formed of earthenware and so that the metallic parts can readily be secured
thereto.
Figure 8 is a side elevation and Figures 9 and 10 are vertical sections taken at
right angles to one another of the switch.
Figure 11 is a plan of the switch chamber Figures 12 an underside view of the
fuse chamber and Figure 13 a plan view of what is called the separate piece.
The "separate piece" A is provided as in the switch just described with a metallic
bush to allow of its being screwed on to any suitable support this bush is formed
at one end with a head of irregular shape to be received into a corresponding recess
and a screw nut is screwed on to its opposite end to retain it in place.
All the other metallic portions of the switch are retained in their respective places
in the same manner.
In the cavity on the upper side of the piece A is a disc B of porcelain or other
insulating material, it carries two metallic bolts B₁ B³. The conductor a is coupled
The disc B has also secured
to the bolt B' and the return conductor b to the bolt B*.
to it two metallic eyelets B³ B+.
C is the piece carrying the switch and safety fuse and which fits as a lid over the
top of the piece A. A ring of leather C may be interposed so that they may fit
together with sufficient friction. A disc of porcelain A' is also placed between them
to separate the cavity on the underside of the piece C from the cavity in the piece A.
The piece C carries two metallic pegs D D₁ projecting downwards from it and
passing through corresponding holes in the disc A and into the metallic
eyelets B³ B₁.
The piece C also carries two metallic bolts E' E' which project upwards into the
switch chamber each bolt has secured to it one end of a metallic spring E. The
opposite and free end of each spring overlaps the fixed end of the other spring as
shewn at Figure 11. . H is a safety fuse carried across from the peg D to one of the
bolts E-from the other bolt a wire conductor is led to one of the terminals of the

page_text: lamp holder which may be screwed on to the metallic bushing of the top cover-of
the switch chamber. I is the ring by which the springs in the switch chamber are
surrounded and by which the free ends of the springs can be forced against the fixed
ends to complete the circuit as in the switch previously described.
When the circuit is so completed the current entering at a passes, as shown by
the dotted lines in Figure 10, to the bolt B' and eyelet B³ then through the peg D
to the safety fuse H and by it to one of the bolts E and springs E and through the
springs to the other bolt E from which a wire conductor is led away to one of the
lamp terminals and returns from the other lamp terminal to the peg D¹ and from it
to the bolt B² to the return conductor b.
At Figure 14 I have shown a cross section of another single pole switch in which
the central boss A of insulating material carries double segments B B forming a
spring clip. The ring C which can have a partial turn given to it carries a single
segment D which when the ring is turned will enter between the segments B and
complete the circuit as indicated by the dotted lines.
In large sized switches any desired number of double segments and single segments
to pass between them may be used.
Figure 15 is a side elevation and Figure 16 a vertical section of my double pole
switch. Figure 17 is a horizontal section on the line a b Figure 15 and Figure 18 a
horizontal section on the line c d Figure 15.
A is the central boss-B the ring turning around it-B¹ handles for turning the
ring a coiled spring contained in a recess in the top of the boss A. It tends to
turn the ring in a direction to turn off the current. The inner end of it is fixed to a
pin A which is fixed in the centre of the boss and the other end is secured to a metallic
block D which is fixed to the interior of the ring B. This block has also secured to
it a metallic tongue E which when the ring has a partial turn given to it can be made
to enter a metallic clip F which is fixed to the central boss. The central boss has
also secured to it one end of another metallic spring G the other being secured to the
interior of the ring-both springs tend to turn the ring in the direction of the arrows
Figure 17. When turned in this direction the current is off. When turned in the
opposite direction the tongue E enters the clip F and a second tongue H enters a
clip I-the current then passes from the terminal J to the metallic rod A¹ and through
the spring C to the tongue E and clip F to a terminal Pl and from the terminal N to
the tongue H and clip I to the terminal N-K K are balls on which the ring B rests
so that it may be turned with but little friction.
Figure 19 is a side elevation and Figure 20 a vertical section of my reversing
switch with one or two rings. Figure 21 is a horizontal section through the upper
part of the switch and Figure 22 a horizontal section through the lower part.
A is the central boss B and C are two rings surrounding it-The upper one B is
for turning the current on and off-the lower one C is for reversing the current-D
and E are metallic clips carried by the ring C and F, G are tongues carried by the
central boss to enter these clips-H is a projection from the exterior of the ring C-
II are holes into either one or other of which a pin J can be inserted. When the
pin is put into one of these holes and the ring is turned so as to bring the projection H
against it the current passes in one direction—but when the pin is put in the other
hole and the projection H brought against it the current is reversed as will be scen
by the electrical connections shown by dotted lines in the drawing. The dotted line X
in Figures 21, 22 represents a connection between the clip D in Figure 22 and the
clip in Figure 21.
The wavy dotted line Z indicates an electrical connection used when the reversing
switch is made with a single ring and when the parts shown in Figures 21 are not
used. When two rings are used the wavy line connection Z is not made.
Figure 23 is a vertical section. Figure 24 a horizontal section and Figure 25 a
plan of my combined switch and galvanometer. Figure 26 is a plan of the upper.
part with the galvanometer index hand and card removed. Figure 27 shews separately
the magnet bar of the galvanometer.

page_text: A is the central boss-it has a hollow chamber formed in it within which is mounted
the galvanometer magnet-B is the moveable ring surrounding the boss-C is a
metallic conductor surrounding approximately one half of the circumference of the
boss B and D is a metallic conductor surrounding the other half. It is formed as a
spring with one end fixed to the pin D' and the other end tending to spring outwards
away from the end of the conductor C-B' is a pin projecting inwards from the
ring B it comes against the spring D and when the ring is turned forces its end
against the end of the conductor C. When this is done an electric current can be
passed from the pin C at the end of the conductor C to the pin D' at the end of the
spring D E is the galvanometer magnet carried on an axis F-E' E' are eyes at
the ends of the magnet. A thread is led upwards from each and one of them after
being passed over a guide pulley is wound around the axis G of the galvanometer
index hand and its end is then attached to a spring H. When an electric current
passes through the conductor C and spring D the magnet is deflected and the axis G
thereby turned in one direction and when no current is passing the spring turns the
axis back again to its former position.
The other thread after being led upwards and over a guide pulley is attached to
the end of a spring I.
By adjusting the relative strengths of the two springs H and I the needle can
readily be set to zero when no current is passing and the resistance offered to
the deflection of the needle when a current passes can also be readily adjusted as
required.
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. The construction of an electrical switch with a central hoss of insulating material
with a spring or springs attached to its exterior and a surrounding ring of insulating
material so formed as when turned to press the free ends of the spring or springs
inwards and thereby complete an electrical circuit through the spring or springs
substantially as described.
2. The means substantially as described for ensuring a good rubbing contact in
electrical switches of the above construction.
3. The construction of an electrical switch in combination with a safety fuse
chamber substantially as described.
4. The construction of combined electrical switches and safety fuse chambers in
such manner that the switch and that part of the safety fuse chamber which contains
the fuse wire can be readily removed from the electrical circuit without disturbing
either of the wire conductors which pass from the switch to the electrical mains
substantially as described.
5. An electrical switch having double segments or spring clips attached to an
insulating boss enclosed by a ring of insulating material having curved metal tongues
or springs attached thereto which enter or come out of their respective clips when
the ring is moved in a circular direction-or a switch in which the double segments
are carried by the ring and the metal tongues by the boss.
6. In electrical switches constructed with a central boss and ring turning around
it as above described the employment of a coiled spring connected at one end to the
boss and at the other end to the ring to tend to turn the ring into a position to break
the circuit.
7. The use of a movable plug for controlling the extent of ring movement when
the switch is used as a reversing current switch.
8. The use of two rings of insulating material one above the other and so arranged
that one may be secured in any desired position while the other can be moved for
switching a current on or off a circuit the electrical connections being such that while
one ring serves to reverse the direction of the current the other merely makes or
breaks the circuit.

page_text: 9. A switch as herein described with a magnetic or electric device for indicating
the direction of an electric current or measuring its strength substantially as
described.
10. The construction of an electrical switch and appliances connected therewith
substantially as herein before described and illustrated at figures 1, 2, 3, 4, 4 A, 5, 6
and 7.
11. The construction of an electrical switch and appliances connected therewith
substantially as herein before described and illustrated at Figures 8, 9, 10, 11, 12
and 13.