Improvements in Junction Boxes for Underground Electric Conductors.
Year: 1899

page_text: Date of Application, 22nd July, 1899-Accepted, 26th Aug., 1899
COMPLETE SPECIFICATION.
Improvements in Junction Boxes for Underground Electric
Conductors.
We, SIEMENS BROTHERS & Co., LIMITED, of 12, Queen Anne's Gate, West-
minster, S.W., Electrical Engineers, do hereby declare the nature of this inven-
tion (as communicated to us from abroad by Siemens & Halske Aktien
Gesellschaft, of Markgrafen Strasse No. 94, Berlin, S.W., Electrical Engineers,)
and in what manner the same is to be performed to be particularly described
and ascertained in and by the following statement: -
At places where connections have to be made to electric conductors portions
of the insulating material or covering have to be removed leaving the wires bare,
or even when these parts have been covered again the insulation may be more or
less imperfect, and short circuiting might occur between such imperfectly insu-
lated parts of conductors of opposite polarity.
This invention relates to means of providing against the risk of such short
circuiting by enclosing the junction portions of two or more adjacent conductors
in separate compartments of the junction box having openings provided with
covers so arranged that when access is given to one of the compartments the
openings to all the others are necessarily closed.
This may be effected in various ways as we shall describe with reference to the
accompanying drawings.
-
Fig. 1 is a section and Fig. 2 is a plan of two compartments a, b for junctions
to and leads respectively, cach compartment is provided with a sliding
cover chaving through it a central opening d. When the cover is moved to
either hand as far as permitted by a stop so as to give access to either compart-
ment through the central opening, the other compartment is necessarily covered,
Fig. 3 is a section shewing two compartments a and b close together, the cover c
being of such length that when it is moved to either hand against a stop, uncover-
ing the one compartment, it necessarily covers the other.
As shewn in Fig. 4, the cover c is in the form of a disc with an opening d
through it which can be brought over either of the compartments a, b by turning
the disc partly round. Fig. 5 shews the cover in form of a segment c which can
be turned only as far as permitted by a slot e in which a stationary pin is
engaged.
As shewn in Fig. 6, each of the compartments ab has a separate sliding cover c
and f. each of which when it is withdrawn crosses the path of the other, as
shewn in Fig. 7 where c being withdrawn prevents f from being moved.
Where there are three conductors, the three junction compartments may be
arranged as shewn in Fig. 8 with covers c, f sliding in one direction. In this
case there are two sliding bolts h, k so arranged that when one, say k is withdrawn
so as to allow the cover f to be moved as shewn in Fig. 9 the bolt necessarily
prevents g from sliding.
When has to be moved both bolts h, k, have to be moved from each other so
s effectually to prevent the movement of c or f.

page_text: Fig. 10. is a plan, and Figs. 11 and 12 are sections on the lines A--A
and B-B of Fig. 10 respectively shewing two compartments ab of a junction box
which is in electrical connection with earth and the middle conductor of a three
wire system.
The
This box is provided with a sliding bolt h which when moved to the one hand
allows to open as shewn in Fig. 10 preventing f from moving, and if moved
to the other hand would allow f to open and prevent c from moving.
junction box in this case is, like the pipes, made of metal, but is preferably
lined with insulating material to prevent short circuiting to earth on the middle
wire while operating on bare parts of the conductors.
Having now particularly described and ascertained the nature of this
invention and in what manner the same is to be performed we declare that what
we claim is:
Junction boxes for underground electrical conductors made in separate com-
partments one for connecting to each conductor, the openings for access to these
compartments being provided with covers so arranged that when one is open the
others are necessarily closed, substantially as and for the purpose set forth.
Dated this 99nd dow of T..1.. 1000
ABEL & IMRAY,
Agents for the Applicants.
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