ELECTRIC INCANDESCENT LAMP HAVING A PINCHED BASE

TRADUCTION NON-DISPONIBLE

English Abstract

PHD.77-093
04-07-1978
ABSTRACT:
An electric incandescent lamp having a
pinched base whose current supply wires have an outwardly
directed bend at the area of the side faces of the pinched
base.

Claims

PHD 77-093
THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. An electric incandescent lamp having a
pinched base from which current supply wires for the fila-
ment project which are bent back outwards the pinched base
in the direction towards the filament, characterized in
that the current supply wires (4 and 5) have a bend dir-
ected outwardly of the base at the area of the side faces
(6 and 7) of the pinched base (2).
2. An incandescent lamp as claimed in Claim 1,
characterized in that the current supply wires (4 and 5) are
flat at least outside the pinched base (2) and each supply
wire has a major face facing the associated side faces
(6 and 7) of the pinched base.

Description

O~ 43
BKS/JFr
04-07-1978
"Electric incandescent lamp having a pinched base".
The invention relates to an electric in-
candescent lamp having a pinched base from which current
supply wires ~or the filament project which are bent back
outside pinched base in the direction towards the filamentO
In known incandescent lamps of this type
:
the current supply wires flatly engage the pinched base on
the outside. In particular when said lamps have small di~
mensions, this often results ln contact difficulties when
the lamp is inserted in corresponding bulb sockets since a
small inclined position of the current supply wires'has for
its result that the contact str-ips in the socket are not
contacted with certain-ty. In addition i~ may occur that the
current supply wires when being inserted into the~soc~et
slide away laterally so that in this case also no correct
::
contact is made with the contact strips o~ the socket. ~l-
~;~ though sQme improvement was~ achieved by flattening the
current supply wire,~oontact difficulti0s are still not
avoided entirely.
It is therefore -the obJect of the invention
to provide an electric incandescsnt lamp having a~ pinchsd
base in which the current supply wire bent back outside the
pinchsd base are constructed so that electrical contact is
ensured when said lamp is inserted :into a corresponding
` socket.
According to the invention this object 19
achieved in an incandescent lamp of the~ kind mentionsd in
- : ,
, ~

43~
PI~D.77-~093
04-07-1~78
the preamble in that the current supply wires have a bend
directed outwardly of the base at the area of the side
faces of -the pinched base.
- The bend is preferably a kink in the
current supply wires.
, As a result of said bend in the current
supply wires, they provide a resilient effect whlch con-
siderably improves their contact with the socket contacts.
In addition it is avoided that the ends of the current
supply wires stand out slightly from the surface of the
pinch as may occur with wires which flatly engage the
pinched base. In the case of bulk package of the latter
lamps, a number of said lamps m~y hook into each other.
In the incandescent lamp according to the
invention the current supply wires, at leas-t outside the
pinched base, are preferably flat and each said current
supply wire has a major face facing the associated side
face of the pinched base.
An embodiment of the invention will now
be described~in greater detail with reference to the ac-
companying drawing. Xn the drawing:
Fig. 1 is a lonogitudinal sectional view
of an incandescent lamp according to the in~ention on a
greatly enlarged scale, and
Fig. 2 is a side elevation of said lamp
in a position rotated through 90 about the lamp axis.~
The incandesc4nt lamp comprises a glass
envelope 1 which has a pinched base 2 at its lo~er end.
8 denotes a sealed e~haust tube. In the incandescent lamp
are posi.tione-l a filament coil 3 whose current supply

~ 3~ 3 PHD 77-093
wires 4 and 5 are incorporated in the pinched base. The
ends 4a and 5a of the current supply wires 4 and 5 pro-
ject from the pinched base 2 and are bent along the pinched
base 2 in the direction toward th~ filament coil 3. The cur-
rent supply wires 4 and 5 ar~ flat and extend with a wide
side major surface adjacent the respective side faces 6 and
7 of the pinched base 2.
The ends 4a and 5a of the current supply
wires 4 and 5 each comprise a respective bend 9 which is
directed outwardly from the base and is in the form of a
kink in the bent wire ends. As a result of said kink 9
the bent current supply wires provide a resilient effect
so that good electrical contact with the socket contacts
is obtained.
The pinched base 2 may be provided on at
least one of its side faces 6 and 7 with a transverse
groove (not shown) which ensures a fixed hold of the lamp
in an associated socket.
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