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Year: 1888

page_text: I, ALEXANDER BERNSTEIN, of 9ª, Commercial Road, Pimlico, in the county of
Middlesex, 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 an improved combined cut-out and switch.
In the specification of Letters Patent granted to me and dated September 28, 1886,
No. 12315, I have described an improved cut-out, for the purpose of preventing the
interruption of the circuit in which glow lamps are placed in series, in case any of
these lamp should break. These cut-outs are now generally made in the form of a
plug and are hereinafter terined "cut-out plugs."
The object of my present invention is to provide suitable receptacles for these cut-
out plugs, so that they can at the same time servo as switches.
In the accompanying drawing
Figure 1 is a plan of my improved combined cut-out and switch, the cover being
removed.
Figure 2 is a view of the plug detached.
Figures 3 and 4 are sectional views, on the line x, x Figure 1, illustrating the
operation of my invention.
a represents a metallic case generally made with two nozzles b and c for the passage
of the wires and for attaching the case to other fittings, and d is a metallic cover by
means of which the case is closed.
e is a piece of insulating material which is fastened on the metal case a and which
carries two metal standards f,g for the reception of the plug, which is screw threaded
at i and has the metal end attached to the part by the insulating strips and the
stud pressing against the compound referred to in my said specification, No. 12315
and placed in a recess in the part 2¹.
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The standard is provided with a screw thread corresponding to the thread on the
plug and the standard g carries a flat spring j which makes contact at one end k with
the end of the plug hand at the other end with the standard when the plug is
not screwed up that is to say, when it is in the position shown in Figure 4.

page_text: m, m' are the main conductors and n, n¹ are the conductors of the lamp circuit, the
said conductors being attached to the standards f, 9.
It will be noticed that a portion o of the plug is tapering so that as soon as the
plug is screwed home the end of the spring is moved out of contact with the
standard as shown in Figure 3.
The effect of this arrangement is as follows:-
As soon as the plug is put in place, as shown in Figure 3, the metal end makes
contact with the end of the spring attached to the standard y, the metal portion i
being in contact with the standard. The two standards f, g aro then only connected
through the metallic compound so that almost the total current passes to the lamp.
If, however, the plug is turned slightly out of the case, so that the end of tho springj
comes into contact with the standard f, the current will be short circuited through
the spring so that no current can pass through the lamp. It will be seen that in
this way the plug answers either as a cut-out or as a switch.
'
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 I
claim is
1. In a combined switch and cut-out, the combination of two insulated standards,
one of which is provided with a screw thread for the reception of the cut-out plug,
and a metallic spring which is firmly attached to one of the said standards and
adapted to make contact with the other, this contact being regulated by the position
of the plug, substantially as described.
2. The manufacture and use of the above described combined switch and
cut-out.
Dated the 10th day of March 1888
G. F. REDFERN & Co.,
4, South Street, Finsbury, London,
Agents for the Applicant.