Light source provided with light reflecting means

A light source includes a reflector, a lamp and a securing mechanism firmly fixing the lamp to the reflector. The reflector includes a reflecting portion and a central hollow neck portion having an inner surface. The lamp includes an envelope provided with a pinch-sealed portion; a light emitting component accommodated in the envelope; and current feedthroughs electrically connected to the light emitting components and passing through the pinch-sealed portion to project outwardly from the envelope. The securing mechanism includes a first metal sleeve tightly surrounding the pinch-sealed portion of the envelope; a second metal sleeve lining the inner surface of the neck portion of the reflector and surrounding the first metal sleeve; and clamping components affixed to the second sleeve. The clamping components fit into the hollow neck portion and encase the inner surface thereof from two opposite sides. The first and second metal sleeves are fixedly secured to one another.

BACKGROUND OF THE INVENTION 
The present invention relates to a light source provided with light 
reflecting means. 
In the light source industry, there are known incandescent and discharge 
light sources provided with light reflecting means, which is to be firmly 
integrated with an incandescent or discharge lamp. During this 
integration, the light emitting component--e.g. the incandescent filament 
in the case of incandescent lamps--is to be in most cases positioned in or 
adjacent to the focal plane of the light reflecting surface. Having made 
this optical adjustment of the relative position of lamp to light 
reflecting means, this position is to be fixed. To achieve this, a 
heat-resistant adhesive, e.g. cement is mostly used, but mechanical means 
are also known. In this connection, the method according to published EP 
application No. 341 633 is referred to. 
The fixation ensured by cementing is less suitable for mass-production 
since the cement has a heat insulating property making it unable to 
conduct the heat generated due to the operation of the lamp and because 
the cementing requires a long time as the cement will not harden 
instantaneously. The time period during which the cement hardens increases 
production times and also increases the risk of a change in the relative 
position of the light reflecting means to the lamp. This latter 
consequence should not be tolerated since it is a fundamental requirement 
for light sources provided with light reflecting means to have a 
controlled light reflection that can only be assured if the light emitting 
component of the lamp--e.g. the filament in the case of incandescent 
lamps--is positioned in the focus of the reflecting surface of the light 
reflecting means. 
Solutions for fixing by mechanical means are described in HU-B 190.574 and 
U.S. Pat. No. 4,370,587. These arrangements can be used exclusively for 
light reflecting means made from metal. 
SUMMARY OF THE INVENTION 
An object of the invention is therefore to provide a light source integral 
with light reflecting means, which can be manufactured in a time-saving 
manner, the optical adjustment of which can be easily accomplished and the 
adjusted position of which is reliably maintained. 
A further object of the invention is to provide a way of firmly fixing a 
lamp and any type of light reflecting means, made from plastic or glass in 
addition to metal, to each other using a mechanical means and also making 
possible a mass manufacture of the light source provided with light 
reflecting means. 
Accordingly, the new light source provided with light reflecting means, 
according to the invention comprises a light reflecting means and a lamp, 
primarily a halogen incandescent lamp, fitted into the central neck 
portion of the light reflecting means and containing a light emitting 
component in a prescribed position relative to the light reflecting means. 
The envelope of the lamp has a pinch-sealed end portion having current 
feedthroughs passing therethrough and a first metal sleeve fixed to it. 
According to the invention the central neck portion of the light 
reflecting means is lined with a second metal sleeve receiving the first 
metal sleeve and the second metal sleeve is provided with components for 
clamping it to the light reflecting means. The second and first metal 
sleeves are joined to each other, preferably by welding. In addition, the 
portions of the current feedthrough inside the first metal sleeve are 
surrounded by an electrical insulator. 
According to a preferred embodiment, the components clamping the second 
metal sleeve to the light reflecting means are limiter tab(s) protruding 
or bent out from the wall of the second metal sleeve and a metal plate 
surrounding the second metal sleeve and joined, preferably by welding, 
with the second metal sleeve. The metal plate is supported on the outer 
edge of the neck portion of the light reflecting means. ("Outer" is the 
intended to mean a position more remote from the lamp.) The electrical 
insulator is preferably a ceramic rod provided with bores to receive the 
feedthroughs and is partly pushed into the first metal sleeve.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
In FIGS. 1 and 2 a 23 V,20 W halogen incandescent lamp 1 provided with 
light reflecting means 3 is shown. The envelope of the lamp 1 is made from 
Vycor or hard glass and ends in a pinch-sealed portion 8, from which 
current feedthroughs 7, made usually from molybdenum protrude. The 
pinch-sealed portion 8 is tightly surrounded by a first metal sleeve 2 and 
the current feedthroughs 7 are, inside the first metal sleeve 2, 
surrounded by an electrical insulator 6. The neck portion 10 of the light 
reflecting means 3 is lined with a second metal sleeve 9 having bent-out 
tabs 4 abutting the inner edge of the neck portion 10 ("inner" is intended 
to mean a position closer to the lamp.) This second metal sleeve 9 is 
joined by welding with a metal plate 5 supported on the outer edge 13 of 
the neck portion 10 of the light reflecting means 3. In case the edges 13 
and 14 of the neck portion 10 of the light reflecting means 3 are, due to 
its processing, parallel to each other, the position of the filament 
height is determined. 
The so-called optical adjustment of the light source provided with light 
reflecting means can be carried out in two ways depending on whether the 
relative position of the light emitting component of the lamp 1 to the 
light reflecting surface of the light reflecting means 3 is adjusted 
earlier by forcing the first metal sleeve 2 on the pinch-sealed portion 8 
or later, when mounting the lamp 1 in the light reflecting means 3. 
When the first method is used, filament position is kept within close 
tolerance limits by fixing the first metal sleeve 2 to the pinch-sealed 
portion 8. Close tolerance limits means that for filament height and 
angle, tolerance ranges of .+-.0,10 mm and .+-.30 minutes are permissible, 
respectively. If it is impossible to ensure that the above close tolerance 
limits relative to the basis formed during the processing are observed as 
early as in base-fitting of the lamp 1, i.e. when the first metal sleeve 2 
is fitted to the pinch-sealed portion 8, then it is this optical 
adjustment that must be carried out prior to joining the light reflecting 
means 3 and the lamp 1. 
Joining of the light reflecting means 3 and the lamp 1 should be finalized 
only after the optical adjustment is completed. Joining is preferably 
carried out by bonding the first metal sleeve 2 and the second metal 
sleeve 9 together by a weld 12, but, of course, any different method, e.g. 
soldering is also conceivable. The second metal sleeve 9 is composed of 
two parts which are preferably joined by a weld 11. The welding operation 
has the advantages of compatibility with the manufacturing process, of 
producing a reliable joint and of requiring a relatively short completion 
time. 
In FIGS. 3 3a and 3b, the second metal sleeve 9 fitted to the light 
reflecting means 3 is seen in more details since the lamp 1 is omitted for 
clarity. 
In FIGS. 4 and 4a, incandescent lamp 1 provided with the first metal sleeve 
2 is shown. This lamp 1 is to be fitted into the light reflecting means 3 
provided with the second metal sleeve 9, as shown for example, in FIG. 3. 
After fitting and, if needed, after performing the optical adjustment, the 
first metal sleeve is joined, preferably by welding, to the second metal 
sleeve 9 as seen in FIGS. 1 and 2. 
The most important advantage of the construction according to the invention 
compared to the conventional solutions is that it makes the use of the 
cement unnecessary for the operation of joining the lamp with the light 
reflecting means. The mechanical joining is simple and it ensures a 
precises fit with close tolerance limits. In addition, by making use of a 
mechanical joining, there is a freedom of choice as to the material for 
the light reflecting means. The construction according to the invention 
enables to join the light reflecting means made from any known appropriate 
material with the lamp. The construction is especially preferable in the 
case of light reflecting means made from plastic.