Improvements in Electrical Switches.
Year: 1899

page_text: Improvements in Electrical Switches.
We, VERITY'S, LIMITED, of Plume Works, Aston, in the County of Warwick,
Electrical Engineers, and Louis JOIN STEELE, of 14, Clarendon Road, Holland
Park, London, W., Electrician, do hereby declare the nature of this invention
to be as follows:-
This invention relates to electrical switches, and particularly to those of the
key type which are arranged with double poles, and are extremely suitable in
high tension circuits.
The improvements according to this invention are characterised firstly, by the
use of an insulating incombustible partition or screen for carrying the shifting
contacts or contact strips by which the terminals are connected, the said par-
tition being so arranged that simultaneously with the breaking of the circuit
a part of it is brought into position between the tips of the terminals for pre-
venting the formation of an arc, secondly, by arranging the contact tips of the
terminals so that the one, or ones if a two-pole switch, shall be separated from
the other, or others, by the insulating partition or screen, as aforesaid, and
arranging the said contact or contacts upon the insulating partition so that
their terminations shall respectively engage the terminals tips, and, thirdly,
in forming the said contacts or contact strips so that parts of them shall con-
stitute stops to the movement of the insulating partition when the latter is in
an off" position.
In carrying the invention into effect in connection with a two-pole fly switch
of the key type, the terminals are fitted to the insulating base or block as ordi-
narily but so that the contact tips of two of them stand out some distance further
than the tips of the other two, the said distance being approximately of an
inch. An insulating incombustible partition, taking the form of a circular disc,
is pivoted to the centre or middle of the base or block so as to partly rotate or
turn within the distance between the tips of the terminals as aforesaid, two of
the tips facing the underside of the disc, and two the top side. This disc carries
the contacts or contact strips, the terminations of which come one on each side
in position for and engaging the tips of the terminals above and below, or on
either side, of the insulating disc, and a spring is fitted to it for moving the
said disc quickly when breaking the circuit, and a thumb piece or turn is fitted
to it for the said disc's operation by the fingers, the movement given to it being
a part rotation. Upon the under or inner terminations of the contacts or con-
tact strips are formed projections or outstanding parts, which constitute stops
against a part of the base or block, or a part connected to it, against the fur-
ther movement of the disc when it has, by the action of the spring, been rotated
sufficient to clear the contacts from the terminals tips.
The contact strips have their terminations inclined in the ordinary way to
form leads to the tips of the terminals, and the parts go together with a good
rubbing contact. Simultaneously with the terminations of the contact strips

page_text: leaving the terminal tips on both sides of the insulating disc another and insu-
lating portion of the said disc comes into position between the terminals, and
all chance of arcing between the said terminals is thereby prevented.
The thumb piece or turn is so connected to the insulating disc or partition
that the last named can have a free movement in a fly off direction, so that if
the turn should be held by the fingers, or moved at only a certain rate, the
insulating disc carrying the said contacts will fly into an off" position inde-
pendently of it.
66
Dated this 15th day of February 1899.
Improvements in Electrical Switches.
We, VERITY'S, LIMITED, of Plume Works, Aston, in the County of Warwick,
Electrical Engineers, and LOUIS JOHN STEELE, of 14, Clarendon Road, Holland
Park, London, W., 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:-
This invention relates to electrical switches, and particularly to those for use
in high tension circuits and known as two-pole switches or, in other words,
switches having double poles.
The improvements according to this invention are characterised firstly, by
the use of an insulating incombustible partition or screen for carrying the
shifting contacts or contact strips by which the terminals are connected, the said
partition being so arranged that simultaneously with the breaking of the circuit
a part of it is brought into position between the active parts or tips of the
terminals for preventing the formation of an arc, secondly, by arranging the
contact tips of the terminals so that the one, or ones if a two-pole switch, shall
be separated from the other, or others, by the insulating partition or screen,
as aforesaid, and arranging the said contacts upon the insulating partition so
that their terminations shall respectively engage the tips of the terminals and,
thirdly, in forming the said contacts or contact strips so that parts of them shall
constitute stops to the movement of the insulating partition when the latter is
in an off" partition.
The invention will be clearly understood by reference to the accompanying
sheet of drawings, which shows the improvements carried into practical effect
in connection with a two-pole fly switch of the key type. In this sheet of draw-
ings Fig. 1 represents a side elevation of such a switch with its casing or cover
in section, and Fig. 2 a plan thereof with the said cover removed; the position
of the parts of the switch in these illustrations being "on." Figs. 3 and 4 are
similar representations as Figs. 1 and 2, but the parts of the switch are in an
"off" position. Figs. 5, 6 and 7 are separate illustrations of the incombustible
partition or screen before referred to and the contacts or contact strips carried
by it, whilst Figs. 8 and 9 are detail sections on the lines 2 and 3 Fig. 2, to
show how the contacts upon the partition engage the terminals above and below
the said partition or upon opposite sides of it.
'
In the switch shown in the drawings the terminals a², w³, a¹, a³, are fitted to an

page_text: insulating base or carrier block as ordinary, but arrangement of their contact
tips is such that two of them stand out some distances further from the insula-
ting base than the tips of the other two; for example, the contact tips ², c³ of
the terminals a³a' extend from the base or block a fully of an inch more
than the contact tips c,, of the terminals a², a³. An insulating incombustible
partition, taking the form of a circular disc of about of an inch in thickness,
is pivoted to the centre or middle part of the base or block a upon a post or
support so as to partly rotate or turn within the distance between the tips
of the terminals, as aforesaid, upon a vertical axis, two of the said tips viz:-
the ones facing the underside of the disc, and two, namely: and
facing the top side d This disc carries fast with it the contacts or contact
strips g, i, by which the terminals are connected, the terminations g²,³, of
each strip being arranged on each side of the said disc so as to engage the tips
of the terminals above and below or on both sides of the insulating disc; for
example, the terminations g³, g², engage the tips 2, 3, and the termina-
tions 3, 3, the tips A spring e² is fitted between the disc and post e
for moving the said disc quickly when breaking the circuit, and a thumb-
piece or a turn m is provided for the said discs operation by a handle m²,
extending through the enclosing casing or cover of the said switch from the
outside.
Upon the under or inner terminations of the contacts or contact strips, i,
are formed projections or parts 0, 02, which constitute stops to the part rotating
movement of the disc din both directions by coming against parts of the base
or block in this instance the terminals a², a³, a², a
The contact strips g,, have their terminations, as aforesaid, inclined or
bevelled in the ordinary way to form leads to the contact strips engaging the
terminal tips, the parts meeting each other with a good-rubbing contact.
It will be clearly understood by reference to the drawings that simultaneously
with the terminations of the contact strips y, i, leaving the terminal tips on
both sides of the insulating disc d, another and insulating portion of the said
disc is brought into position between the terminal tips, so any chance of arcing
between the said tips or terminals is prevented.
The thumb piece or turn m is so connected to the insulating disc or portion d
that the last named can have a free movement of the thumb piece in a fly off
direction, so that if the said turn after starting the flying off movement of the
dise should be held by the hand or moved at only a moderate rate it cannot
hold the insulating disc in a position to cause arcing, the said disc flying off
independently of the said turn. This movement is obtained by forming a gap
in the underside of the turn m of greater width than the part m' it engages
on the disc d.
The disc or partition & may be ebonite or any other suitable material which
is incombustible and a good insulator, and it may be varied in thickness and
size according to the particular circuits for which the switch is desired.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what
we claim is: -
First. In electrical switches, arranging the contact tips of the switch ter-
minals so that the one or ones project or stand out further than the other or
others, and providing to work between the said tips a fly-off part-rotating insu-
lating incombustible partition or screen carrying contacts or contact strips, for
the purposes substantially as described and set forth.
Second. In electrical switches, the combination of a fly-off part-rotating par-
tition or screen, contacts or contact strips carried on said partition so that their.
terminations extend above and below, stops all in one piece with said contact
strips and switch terminals whose contact tips are arranged on different sides

page_text: of the said partition to engage the terminations of the strips as aforesaid, sub-
stantially as described and for the purposes set forth.
Third. A two-nole electrical switch having its parts constructed arranged and
adapted to operate (less the thumb piece or turn) in the manner described and
set forth in Figs 1 to 9.
Fourth. The general construction and arrangement of switch specifically des-
cribed and set forth in Figs. 1 to 9.
11
1000
W. P. THOMPSON & Co.,
11, Burlington Chambers, New Street, Birmingham,
also at Liverpool, London and Manchester,
Patent Agents for the Applicants.