Improvements in and connected with Porcelain interiors for Electric Incandescent Lampholders.
Year: 1899

page_text: Communicated from abroad by ACTIEN GESELLSCHAFT MIX & GENEST, Electrical
Engineers, of 67, Bulow Strasse, Berlin W., in the German Empire.
Improvements in and connected with Porcelain interiors for Electric
Incandescent Lampholders.
I, HERMANN OPPENHEIMER, Electrical Engineer, of 55, Redcross Street,
Barbican, London, E.C., in the County of Middlesex, do hereby declare the
nature of this invention to be as follows:
The present invention relates to a porcelain interior for bayonet sockets,
which is so constructed that the insulating qualities of same are considerably
enhanced. The front part of the interior, .e. that part facing the contact
plates of the lamp, shows two holes through which the plungers pass from
behind. Between these two holes the porcelain is grooved out, which increases
the distance between one plunger and its fellow to such an extent that arcing
on an electric light circuit of high pressure cannot take place. On the back of
such interior however there are two contact plates let into the porcelain in such
a manner that it is practically encircling the contact plates which are separated
by a porcelain bridge, the centre of which is of a greater height so as to increase
the distance between the two plates, and exclude the possibility of short-circuit-
ing same, or a short between plate and brass body of the holder itself.
Dated this 27th day of October 1899.
COMPLETE SPECIFICATION.
Improvements in and connected with Porcelain Interiors for Electric
Incandescent Lampholders.
I, HERMANN OPPENHEIMER, Electrical Engineer, of 55, Redcross Street,
Barbican, London, E.C., in the County of Middlesex, 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 present invention relates to a porcelain interior for bayonet sockets,
which is so constructed that the insulating qualities of same are considerably
enhanced. The front part of the interior, i.e. that part facing the contact
plates of the lamp, shews two holes through which the plungers pass from
behind. Between these two holes the porcelain is grooved out, which increases
the distance between one plunger and its fellow to such an extent that arcing
CD Q17

page_text: on an electric light circuit of high pressure cannot take place. On the back of
such interior however there are two contact plates let into the porcelain in such
a manner that it is practically encircling the contact plates which are separated
by a porcelain bridge, the centre of which is of a greater height so as to increase
the distance between the two plates, and exclude the possibility of short-circuit-
ing same, or a short between plate and brass body of the holder itself.
On accompanying drawing, I shew in Fig. 4 a section of the interior,
upside down. In Fig. 2 the bottom view, in Fig. 3 the top view, and Fig. 1
the interior inserted into the metal case of a lampholder.
Between the openings, through which the plungers a pass, there is grooved
out a recess while the contact plates are surrounded by an S-shaped rib d,
which is specially raised in its centre part at the point f.
This arrangement increases the distance between the two contact plates, and
excludes the possibility of short-circuiting same, or a short between the brass
body of the holder and the plates respectively, or between the plates and earth,
whereby an exceedingly high insulation is attained.
Instead of one groove b and rib d, a number of same can be employed.
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. A porcelain interior for lampholders having a groove b between the plungers
and a rib or bridge between the contact plates c, fully as described and for
the purpose set forth.
2. An interior for lampholders having more than one groove between the
plungers, and more than one rib & between the contact plates c, fully as de-
scribed and for the purpose as specified.
Dotod his 92d day of T1
1000
HERMANN OPPENHEIMER.