Year: 1898

page_text: Date of Application, 1st Apr., 1898
Complete Specification Left, 7th Dec., 1898 -Accepted, 25th Mar., 1899
PROVISIONAL SPECIFICATION.
Electrical Switch.
FREDERICK NUNNS, Shaw Syke, Halifax, Mechanical Engineer, do hereby
declare the nature of this invention to be as follows:--
The electrical switch consists substantially of base and cover of porcelain or
other suitable material the cover is kept in possition by pin seccured into base
and passing through the center of cover with knob screwed on the end and
sholdered against the face of cover. A boss is moulded on the inside of cover or
fastened by other means for the purpose of working the contact bars that work
on the center pin. In turning the cover to the right or the left the boss presses
against the contact bars and turns the switch on or off as the case may be.
Dated thin 21at doy of March 1898
I, FREDERICK NUNNS, of Shaw Syke, Halifax, in the County of York, 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:-
The object of my invention is to provide a quick break switch of the ordinary
appearance which is suitable for higher voltages than the ordinary switches which
have faults through not being sufficiently long in the break and not having the
poles wide enough asunder, also in not having an automatic quick break which
is independent of the lever.
The switch consists essentially of a base and cover of porcelain or other suitable
material together with a movable boss preferably of ebonite which carries contact
bars in a groove on its lower surface and is mounted on a central pivot fixed in
the base so as to be able to oscillate freely when actuated by means of a notched
tumbling lever articulating with a metal pin on the upper surface of the ebonite
boss. The lower surface of the ebonite boss is level with the notches in two slotted
terminals which are fixed by screws through the base and are placed one on either
side of the said boss so that the contact bars, when the tumbling lever is operated.
are swivelled into the notches, and make contact. A quick break is secured by
means of a spring which is attached to a limb of the bridge or carrier and caused
to press against the pin on the ebonite boss which articulates with the tumbling
lever. The bridge is secured to the base by means of screws and at its upper end
has a short tubular piece through which the tumbling lever passes and which is

page_text: pinned through at right angles with the axis so as to rock freely within the
tubular piece. The outer surface of the latter is also threaded in a suitable way
to allow of the cover being similarly threaded in its centre so that when the cover
is screwed on, it makes a compact fixture with the base.
The invention will be more particularly described with reference to the accom-
panying drawings in which,
Fig. 1 is part sectional elevation of my improved electrical switch,
Fig. 2 plan view of same and
Fig. 3 an opposite view to Fig. 1 looking in the direction of the arrow a.
The base of the switch is shown at 6 provided with a covering c made of porcelain
or other suitable material, such cover being removed from Fig. 2. Under the
cover c is an arch d made secure to the base 6 by screws e. A tumbler is shown
at f and it is capable of rocking to the right or left upon a pin g passing at right
angles through a screwed thimble h rising up from the bridge d to which the
cover c is screwed. The bottom end of the tumbling lever f is slotted and en-
compasses a short pin i rising up from the ebonite boss, j resting upon the base b,
on the underside of which boss are the contact bars 7 and m, which are fixed in
a groove under the ebonite boss i so as to come flush with the under surface of said
boss, by means of a thick metal screws which is bored up its centre so as to ride
or pivot on a pin or pointed screw w fixed in the centre of the base b. Therefore
when the tumbler f is in the position shown in Fig. 2 and Fig. 3 the contact
bars and m are clear and the contact broken; but on tilting the tumbler in the
other direction as shown in dotted lines Fig. 3 then the contact bars are switched
into slots n in the terminals o and p and electric contact is made, thus by simply
oscillating the tumbling lever f the slot in the bottom thereof causes the pin i
to turn the ebonite boss jaround in one or other direction for putting the switch
into and out of action. In order to break the contact very quickly a spring is
employed, one end of which is rigidly fixed to the bridge d whilst the opposite
end of said spring is loose and acts against the vertical pin i so that on the
tumbler being turned to break contact the spring r will cause the boss i to
oscillate quickly and thus a sudden action is imparted to the contact bars 7 and m.
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. An electric switch consisting of a porcelain base and cover, oscillating contact
bars such as and m secured to a centrally operated boss such as j, slotted terminals
such as o and p, bridge piece such as d, spring r, pin i and tumbler f for operating
the latter and through it the boss j and contact bars and m, substantially as and
for the purposes described.
2. A switch for electrical purposes constructed, arranged and operating sub-
stantially in the manner described and as shown in the accompanying drawings.
Dated this 6th day of December 1898.
TAYLOR & FIRTH,
Osborne Chambers, 48, Sunbridge Road, Bradford,
Agents for the Applicant.
TAYLOR & FIRTH,
Osborne Chambers, 48, Sunbridge Road, Bradford,
Agents for the Applicant.