US 4,994,707 AGranted

Vibration-resistant single-ended halogen incandescent lamp

AssigneePatent-Treuhand Gesellschaft fur elektrische Glum.b.H.

InventorRoland Stark

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Abstract

To reliably retain a filament (13) axially aligned in a bulb (2) of a halogen incandescent lamp, a first current supply lead (8) is shaped to engage the inner wall (14) of the bulb at spaced corners or bend points (16, 21, 22, 424), the corner or bend points being connected by connecting legs (17, 18, 425). The legs and corner points can be arranged in triangular configuration (FIGS. 1-3; FIGS. 10-13) or in cross shape (FIGS. 4-9), and the remote end (15) of the filament, weld or push-connected to the connecting legs or end portions of the current supply lead. The polygonal corner and bend point engagement with the inner wall of the tube provides for substantially improved resistance against vibration of the filament; the engagement of the first corner or bend point, which bends the upper portion of the current supply lead towards the interior of the bulb and towards the filament, upon vibration, results in axial deflection, thereby maintaining the filament in axial position and preventing lateral excursion.

A single-ended halogen incandescent lamp (1) having

a cylindrical bulb (2) of transparent material;
a base (5);
an axially extending coiled incandescent filament (13) defining an axis and further defining a base end (24) and a remote end (15);
a filament mount (10) connected to and coupled to the respective ends (15, 24) of the filament and including
a cross bar (12) of non-conductive material;
and
two internal current supply leads (8, 9) passing through the cross bar and being retained in position thereby,
one (8) of said current supply leads extending parallel to the axis (A) of the lamp towards the remote end of the filament and there defining an upper portion (8a),
the other (9) of said current supply leads extending towards the base end of the filament and being connected thereto;
and
a press seal (4) securing the mount (10) in the bulb,
wherein a first corner or bend point (16) located in a vertical plane parallel to the axis of the filament is formed in said one current supply lead (8), said first bend point being located at about the level of the remote end of the filament, and extending said one current supply lead away from the wall in said plane;
said upper portion (8a) extends beyond said first corner or bend point (16) inwardly of said bulb (2);
said one current supply lead being further formed with at least one second and third spaced corner or bend point (21, 22);
a first connecting leg (17) located between the first corner or bend point (16) and the second corner or bend point (21);
a second connecting leg (18) located between the second corner or bend point (21) and the third corner or bend point (22);
wherein all of said corner or bend points (16, 21, 22) are in engagement with the inner wall (14) of the bulb (2);
and
wherein the remote end (15) of the filament (13) is secured to said upper portion (8a) of said one current supply lead (8) in a region thereof beyond said first corner or bend point (16).

16 more elements

Abstract

Claims42