Year: 1897

page_text: PICctrical WILCnes.
I, ALFRED WATSON, of Hockley Street, 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 employed for making and breaking
the circuit of an electric current, and particularly to that class of switch in which
one or more pivoted or rocking contact arms or bars are arranged to come between
corresponding pairs of contact pieces in order to complete a circuit, which is broken
when the said bar is rocked in the reverse direction out of contact with the said
pieces, which form the terminations of, or are in electrical connection with, the
current lead wires, although the said improvements are applicable to switches in
which the contact-making bars have a sliding movement.
My invention consists in an improved construction of the contact arms or bars,
and in carrying out the same in connection with a double pole arc-light switch, I
proceed as follows:-
I mount upon a suitable insulating base board, two pairs of contact blocks or
pieces, the outer blocks being respectively in connection with the positive and
negative poles of the dynamo, whilst the inner blocks are connected to the corre-
sponding lead wires of the lamp or lamps. Arranged in proximity to these con-
tact blocks are two contact-making bars or arms (of the special construction here-
after described) mounted, so as to be capable of a rocking movement, upon
elevated pivots, which also support a pair of inverted U or like shaped rocking
frames, controlling the contact arms and being coupled, so as to move together,
by means of a bar of ebonite or other insulating material, and so adapted
that, when rocked in one direction by means of a suitable handle or turn, the edges
of their crossing bars, which may be of a V section, bear upon parts of the pivoted
contact arms, forward of the joints, and press their contact ends
between their respective terminal pieces and 80 make circuit, but
when the said frames are turned over and made to bear upon parts of the bars
rearward of their fulcra, then the said bars are rocked in the reverse direction, out
of contact with the two pairs of terminals, and thus double-break the circuit.
I make each of the said contact arms of a spring frame construction, that is,
I take a strip of copper or other good conducting metal, of suitable substance to
carry the required current, and bend the same about its middle nearly upon itself
into an elongated U or similar figure, the free ends of which are bent inwards at
a right angle and terminate in opposed ears or parts running in the longer direc-
tion of the spring frame. When in position the rearward part of the spring sided
frame or skeleton bar is mounted upon the elevated pivots, whilst the other and
contact-making end is adapted to be forced, by the means described, between the
terminal blocks, whose top inner edges may be bevelled to form a lead, whereby
the opposed plate like terminations of the spring sides are pressed into close con-
taci, so that current passes from the one block and directly through the contact-
ing ends of the switch-arm sides to the other block, whilst when the said switch

page_text: arins are in the "break" positions the opposed terminal faces of the sides are,
y the slight spring of the metal, separated from one another to a short distance.
The spring contact arms need not necessarily he made from a continuous
strip of metal fashioned as described, as it may be made up of two or more parts
connected together and arranged in any suitable way so long that the same has
prine-sides terminated by opposed plates adapted to be closed into electrical
connection with one another when the switch arm is in its make position.
The invention is applicable to single or multiple break switch for various pur-
poses and to all types of switches having rocking or sliding contact arms or bars,
the application of my said improvements to these forms differing in no essential
respect from its application to a double pole and double break are-light switch as
herein described.
I, ALFRED WATSON, of Hockley Street, 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 employed for making and breaking
the circuit of an electric current, and particularly to that class of switch in which
one or more pivoted or rocking contact arms or bars are arranged to come between
corresponding pairs of contact pieces or terminals in order to complete a circuit,
which is broken when the said bar is rocked in the reverse direction, it being
understood that the said contacts or terminals form the terminations of, or are in
electrical connection with, the current lead wires. The said improvements are
also applicable to switches in which the contact-making bars have a sliding move-
ment.
My invention consists in an improved construction of the contact arms or bars,
and consists essentially in making the said bars or arms of a spring construction,
or in the form of a spring sided frame, parts of which are presented to one another
and are adapted when the bar is in its make position, to come or be closed together
and make a solid and direct connection between the contact plates or terminal
fittings of the switch.
Figure 1 of the accompanying drawings represents a side elevation of a single-
break switch for arc-lights and other purpose, fitted or provided with an improved
spring-sided contact bar constructed according to one form of my invention.
This view shows the bar in its "break" position.
Figure 2 is a topside plan of Figure 1.
Figure 3 is a like view as Figure 1 but showing the bar in its "make" position
for making electrical connection between the terminal fittings of the switch.
Figure 4 shows the said switch partly in plan and partly in section upon the
dotted line, Figure 3 and with the switch bar in the same position, as in
Figure 3, whilst Figure 5 is a cross section of Figure 3 upon the dotted line..
These two views Figures 4 and 5 represent how opposed parts of the spring sides of
the contact bar are forced into close contact for making a perfect connection when
the said bar is closed into position between the terminals.

page_text: Figure is a like cross section as Figure 5, but represents the switch bar
before entering the space between the terminals and before the opposed end parts
are forced into contact.
Figure 7 represents a plan of the switch bar separately.
The same letters of reference indicate corresponding parts in the said Figures 1
to 7.
a is the base of the switch, which is made of china or other insulating material
and upon which is mounted the separated terminals and e, having binding
screws, e, or other expedients for connecting the lead wires of the circuit thereto,
whilst is a rocking contact bar, mounted and turning upon an elevated cross
pin, or pivot el, supported by ears e, secured to the base, and to which a fly action
is given for ensuring rapid breaking by a suitably arranged spring such as f.
The said contact bar is rocked to and fro for taking it in and out of its circuit
making position by means of a lever g, jointed at its lower end gl, upon the said
cross pine, and having a collar or acting foot g, which, when brought to bear
upon the top of the contact bar forwards of the joint, forces the front end of the
same into position between the terminals b. and e as in Figures 3, 4 and 5 and
when caused to act on a part of the bar behind the joint, the said bar is turned in
the reverse direction and from between the terminals, whereon the action of the
spring f. impels the bar into the position shewn in Figures 1 and 2.
The said contact arm which is, as aforesaid, of a spring frame construction, is
preferably made by taking a strip of copper or other good conducting metal, ot
suitable substance to carry the required current, and bending the same about its
middle nearly upon itself into an elongated U or similar figure, the free ends d',
of which are turned inwards at a right angle and terminate, in opposed ears or
plates, such as . When in position the rearward part of the spring-sided frame
or skeleton bar is mounted upon the elevated pivot whilst the other and contact-
making end is forced between the terminal blocks (whose top inner edges may be
bevelled at,, to form a lead for the sides of the bar) whereby the opposed
plate ends or terminations of the spring sides are pressed into close contact as
represented in Figures 4 and 5 and form a direct and solid connection through
which the current passes from the one terminal to the other, whilst when the said
switch arm is in the break position the opposed terminal faces of the sides are,
by the slight spring of the metal, separated from one another to a short distance.
The spring contact arms need not necessarily be made from a continuous strip
of metal fashioned as described, as it may be made up of two or more parts con-
nected together and arranged in any suitable way so long that the same has
spring-sides terminated by opposed plates adapted to be closed into electrical
connection with one another when the switch arm is in its "make" position.
"
"
Or where a heavy current has to be carried, the switch bar may be made in the
form represented in Figure 8.
Figure represents an elevation and Figure 10 a plan of a double pole double
break are light switch provided with contact bars made according to my invention.
In this arrangement is the insulating base board, and b, and c are two pairs
of contacts or terminal fittings, the outer ones b. being respectively in connection
with the positive and negative poles of the dynamo, whilst the inner blocks c. are
connected to the corresponding lead wires of the lamp or lamps. Arranged in
proximity to these contact blocks are two contact-making bars or arms d, d¹, of
the special construction hereinbefore described, which are mounted, so as to be
capable of a rocking movement, upon the elevated pivots, which also support a
rocking closer frame f. controlling the contact arms, adapted when rocked in one
direction by means of the suitable handle or lever f¹, to either bear upon parts of
the pivoted contact arms. forward of their joints and so press their contact-
making ends between the respective pairs of terminals for completing the circuit,
or to bear upon parts of the said bers rearwards of their centres and thus rock
the bars in the reverse direction for double-breaking the circuit.
The invention is applicable to other types of single, double or multiple-break

page_text: switches for various purposes and also to all forms of switches having sliding
contact arms or bars, the application of my said improvements to these forms
differing in no essential respect from its application to single and double pole
arc-light and similar switches as herein described.
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
First In the contact hars or arms of electrical switches, making the same of
a spring-sided frame construction, with ears or opposed parts, which, when the bar
is in its circuit-closing position, are forced together or abut and make a solid
and direct connection between the contact plates or equivalent terminal fittings
of a switch, substantially as described and set forth.
Secondly:- A contact bar for electrical switches, consisting of a spring sided
frame, the free ends of which are provided with returned ears or plates adapted
when the bar is in its circuit-making position to be forced together or abut, sub-
stantially as and for the purpose described and set forth in Figures 1 to 7, 9 and 10.
Thirdly The modified form of switch contact bar, substantially as herein
described and represented in Figure 8.
:
Dated this 94th day of ་--csnt 1000
ALFRED WATSON,
By Henry Skerrett,
24, Temple Row, Birmingham, Agent for Applicant.