Improvements in Electrical Switches.
Year: 1894

page_text: Improvements in Electrical Switches.
I, WILLIAM M° GEOCH the younger, of the Firm of William McGeoch and
Company, of Warwick Works, Coventry Road, in the City of Birmingham,.
Electrical Engineer, do hereby declare the nature of this invention to be as.
follows:-
This invention relates to electrical switches of the fly or bar or bridge type, and
consists, in the one part, in the, construction and mounting of the fly switch;
secondly, in spring-operating of the same, and thirdly, in general arrangement and
combination of the parts.
In constructing a one-way switch according to my invention, I mount upon a
porcelain or slate base, a bridge shaped bracket, having between its uprights, a box
or casing, into which the inner or shank end of a cranked contact bar extends,
and to which is fixedly fitted the inner end of the stem of a button or turn,
the shank of which stem passes through a hole in the top of the said casing.
The lower cranked part of the contact bar is directed horizontally, and is folded
at its end nearly upon itself, forming a hook like termination, and turns angularly
through a portion or a quarter of a circle, and, when moved in one direction, makes
contact, and when in the other, breaks the same. The on contact is made from
the termination of a conducting strip, having connection with a binding screw and
being cranked upwards to form a spring tongue, which overhangs a second con-
ducting strip leading to a second binding screw.
Instead of the end of the contact bar being hooked, it may be plain and insulated
with ebonite or other suitable material.
The hooked or insulated end of the spring contact bar, when in an on position,
makes intimate contact between the spring tongue of the one conducting strip and
the end or adjacent termination of the other conducting strip.
The means for imparting the fly action to the contact bar consists of two lever
loop springs, each having two radially directed arms connected with a loop coil,
and with their free ends turned down hook wise and with the hooks at the
extremities of the longer and outer arms engaging with holes in the box casing,
whilst the hooks of the shorter and inner arms take into holes situated at two
opposite points and out of the centre of motion of the contact bar, so that when
the contact bar is turned to the "make" position, the springs are made active, but
when the said bar is released from the spring tongue of the on contact, then the
springs take the same back to its "break" position, hence the rapid making and
breaking of contact and the switching on and off of current.
The button or turn stem is like unto a key end with a double bit, whilst the
button or turn (which is detachable) has a hole up its middle, shaped to take upon
the said key end, to which it is affixed by a small screw taking through a part of
the turn and down the middle of a portion of the stem.
Or instead of the stem being of a key figure, it may be alike unto a square
stump, having a bearing collar or collett at its lower part, or it may be oblong in
cross section.
In constructing a two-way switch, viz., a switch having "on," "full" and "glow"
positions, I arrange the button bridge-bracket casing and fly contact bar, the same
s before described and with the contacts in the same relative positions, but

page_text: "
with the addition of a supplementary branch, directed opposite to the "break
position and so arranged that the end of the contact bar comes nearly approxi-
mate to it, so as to admit of the passage of the full current through the
conducting plates whilst the glow is produced by an independent arrangement
outside the switch.
The whole of the before described switches are provided with suitable caps or
covers, inscribed, in the case of a one-way instrument, with the words "full" and
"off" and in a two-way instrument, with the words "full," "off" and "glow,"
indicative of the position of the contact bar.
A key switch provided with my improvements is of the usual construction,
having an enlarged upper part, fitted with an insulating base, carrying the contact,
conducting plates, and binding screws and with an upper shell cap part taking over
them, which shell is slotted at its side wherethrough a thumb turn for working a
cranked and spring operated fly contact bar, passes. The springs for operating
the said contact bar are arranged as before described within a box or casing affixed
in the interior of the dome part, so that by turning the thumb or lever turn contact
is rapidly made and broken.
The upper part of the dome is fitted with the usual split clamping means or
nipples through which the leads take.
The lower and upper parts of the casing are screwed or otherwise connected
together.
It will be understood that a one-way switch can be worked with one spring, but
that in a two-way switch, two springs are essential.
Dated this 15th day of November 1894.
Improvements in Electrical Switches.
1, WILLIAM MCGEOCH the younger of the Firm of William McGeoch and
Company, of Warwick Works, Coventry Road, in the City of Birmingham,
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 :-
This invention relates to electrical switches of the fly or bar or bridge type, and
cousists, in the one part, in the construction and mounting of the fly switch,
secondly, in spring-operating of the same, and thirdly, in general arrangement and
combination of the parts.
In constructing a one-way switch according to my invention, I mount upon a
porcelain or slate base, a bridge shaped bracket, having between its uprights, a
box or casing, into which the inner or shank end of a cranked contact bar extends,
and to which is fixedly fitted the inner end of the stem of a button or turn, the
shank of which stem passes through a hole in the top of the said casing.
The on
The lower cranked part of the contact bar is directed horizontally and is
folded at its end nearly upon itself forming a hook like termination, and turns
angularly through a portion or a quarter of a circle, and, when moved in one
direction, makes contact, and when in the other, breaks the same.
contact is made from the termination of a conducting strip, having connection with
a binding screw and being cranked upwards to form a spring tongue, which
overhangs a second conducting strip leading to a second binding screw.

page_text: Instead of the end of the contact bar being hooked, it may be plain and
insulated with ebonite or other suitable material.
The hooked or insulated end of the spring contact bar, when in an on position,
makes intimate contact between the spring tongue of the one conducting strip and
the end or adjacent termination of the other conducting strip.
The means for imparting the fly action to the contact bar consists of two
levering loop springs, each having two radially directed arms connected with a
loop coil, and with their free ends turned down hookwise and with the hooks at
the extremities of the longer and outer arms engaging with holes in the box
casing, whilst the hooks of the shorter and inner arms take into holes situated
at two opposite points and out of the centre of motion of the contact bar, so
that when the contact bar is turned to the "make" position, the springs are made
active but when the said bar is released from the spring tongue of the "
contact, then the springs take the same back to its "break" position, hence the
rapid making and breaking of contact and the switching on and off of current.
Thus, when the contact bar is disengaged from the "make" position by a slight
turn, then the springs which are active, automatically take or fly-back the said bar
to the break position.
on
"
The button or turn stem is like unto a key end with a double bit, whilst the
button or turn (which is detachable) has a hole up its middle, shaped to take upon
the said key end, to which it is affixed by a small screw taking through a part of
the turn and down the middle of a portion of the stem.
Figure 1 of the accompanying drawing represents a plan of a one-way electrical
switch, with the parts constructed, arranged and provided with improvements made
according to my invention.
The casing or cover is removed in order to show the interior mechanism of the
instrument.
Figure 2 represents a horizontal section of Figure 1 through the box or casing
wherein the spring mechanism for effecting the return fly of the contact bar is
contained.
Figure 3 is a vertical section upon the dotted line - Figure 1.
Figure 4 is a like plan as Figure 1, but with the box containing the spring
mechanism removed, so as to show the quadrant slot wherein the shank of the
contact bar traverses in making or breaking contact.
Figure 5 represents an underside plan of the spring-containing box upon an
enlarged scale, showing the levering springs therein, and how their free ends are
made fast to or engage with the top of the casing and the disc carrying the
contact bar respectively; said springs are shown in their compressed and active
state.
Figure 5 shows a like view as Figure 5, but with the contact bar in its off
position and the levering springs in their normal and inoperative condition.
The same letters of reference indicate corresponding parts in Figures 1 to 5.
Mounted upon a porcelain, slate or like base a, is a bridge-shaped bracket b,
having located between and supported by its uprights, a box or casing c, through a
quadrant slot c¹, in the bottom of which, the shank end d¹, of the contact bar d,
whose outer end is thickened and insulated at d², extends and terminates in a
disc d³, which carries and has made fast to it a stem d, having side lugs or
wings d, and upon which a button or turn e, is fitted and is secured to the
stem by a small screw e, taking down the middle of the stem , hence the
connection.
Located within the interior of the casing c, are two levering springs c², each
having spring arms c³, c, with the turn down free ends of the arms c', engaging
with holes in the top of the box c and with the turn-down free ends of the
arms e, engaging in holes do, in the disc d³. On the disc d³, being turned by means
of the button e, the springs 2, are compressed so that when the hold on the turn or
button is released, the springs tend to again resume or fly back to their normal

page_text: position as represented in Figure 5ª, and carry the disc and contact bar with them,
hence the fly action.
The lower part of the contact bar d, which has a thickened end d is insulated
at d from the outer contact tip (see Figure 3), which said bar turns angularly
through a quarter of a rotation, and when moved in one direction makes contact
between the overhanging spring tougue f¹, of the conducting strip, and the
opposed end gl, of the conducting strip g, both of which strips are in connection
with the circuit wires f, g, through the medium of binding screws f³, g³.
The mechanism of the switch may be enclosed by dome-shaped sheet metal or
other casing h.
Instead of the turning stem being of a key figure, it may be alike unto a square
stump, having a bearing collar or collett at its lower part, or it may be oblong in
cross section.
In constructing a two-way switch, viz., a switch having "on," "full" and
"glow" positions, I arrange the button, bridge-bracket casing and fly contact bar,
the same as before described and with the contacts in the same relative positions,
but with the addition of a supplementary branch, directed opposite to the "break"
position and so arranged that the end of the contact bar comes nearly approxi-
mate to it, so as to admit of the passage of the full current through the
conducting plates, whilst the glow is produced by an independent arrangement
outside the switch.
The switch is provided with a suitable cap or cover, inscribed, with the words
"full,'
," "off" and "glow," indicative of the position of the contact bar.
Figure 6 represents a plan of such a switch, with the casing, the contact bar and
the turn removed, whilst Figure 7 represents a like view but with the bridge
bracket removed also, in order to show the relative positions of the conducting
strips and the spring tongue carried by them. In Figures 6 and 7 f, g and i are
the conducting plates, the first and last of which have spring tongue contacts f, i¹,
whilst the whole of the said plates are in connection with binding screws f³, g³
and and circuit wires f2, 92 and 2.
The switch is provided with a bridge bracket, fly springs and casing, contact-bar
and other cognate parts alike unto the form previously described.
A key switch provided with my improvements is of the usual construction,
having an enlarged upper part, fitted with an insulating base, carrying the contact,
conducting plates, and binding screws and with an upper shell cap part taking over
them, which shell is slotted at its side, wherethrough a thumb turn for working a
cranked and spring operated fly contact bar, passes. The springs for operating
the said contact bar are arranged as before described within a box or casing affixed
in the interior of the dome part, so that by turning the thumb or lever turn contact
is rapidly made and broken.
The upper part of the dome is fitted with the usual split clamping means or
nipples through which the leads take.
The lower and upper parts of the casing are screwed or otherwise connected
together.
Figure 8 represents an elevation of a key switch, containing mechanism (shown
in dotted lines) of a similar construction to that shown in Figure 1.
h is the casing, e the turn, d the contact bar, f' the spring tongue and c the
fly-spring containing casing.
It will be understood that a one-way switch can be worked with one spring, but
that in a two-way switch, two springs are essential.
Having now particularly described and ascertained the nature of my said inven
tion, and in what manner the same is to be performed, I declare that what
claim is :-
First. In electrical switches, the means herein described for spring-operating the
fly contact-bars, substantially as set forth.

page_text: Secondly. The general construction, arrangement and combination of the parts
of electrical switches substantially as herein described and set forth.
Dated this 31st day of July 1895.
VILLIAM MºGEOCH, JUNIOR,
By Henry Skerrett,
24 Temple Row, Birmingham, Agent for Applicant.
WILLIAM MºGEOCH, Junior,
By Henry Skerrett,
24 Temple Row, Birmingham, Agent for Applicant.