Patent Application
20100315821
The present invention relates to a diffuser attachment for a portable lamp, in particular a flashlight or helmet lamp, which permits anti-dazzle, spatial illumination of the environment, for example in a tent, recreational vehicle or trailer or in a cave.
The prior art discloses camping lights which have a base with a receptacle for batteries and a light source and a transparent diffuser attachment mounted over the light source, fixed to the base and comprising at least one integrated reflector element. These lamps produce anti-dazzle, diffused light which ensures uniform illumination of the environment.
However, such camping lights are relatively large and therefore also relatively heavy. Particularly in the area of outdoor activities, such as trekking or mountaineering, however, it is advantageous to keep the weight and the size of the articles carried as small as possible. It is therefore the aim of the present invention to offer walkers, climbers, cave explorers, others involved in indoor and outdoor sport activity and camping enthusiasts a simple and effective possibility which enables them to dispense with additionally carrying a camping light.
The prior art discloses, inter alia, special caps for commercially available, translucent or transparent water bottles in which a plurality of solar LEDs are integrated. In this way, a liquid-filled water bottle can be converted to function as a camping light which emits diffused light which is suitable for spatial illumination at close range, for example in the interior of a tent.
Since the standard equipment of a walker or camper nowadays includes as a rule a flashlight or helmet lamp, these are also frequently used for illuminating the interior of a tent and therefore likewise offer an alternative to a camping light.
The disadvantage of a conventional flashlight or helmet lamp when used as a camping light is, however, that it produces a directed light beam from one or more LEDs and therefore achieves only a small spatial illumination. In addition, the light beam has a strong dazzling effect and is therefore disadvantageous for use in the interior of a tent.
However, the prior art also discloses modified helmet lamps in which, for producing diffused light at close range, a substantially planar diffusing lens, such as a cover, can be pushed, rotated or swiveled from a lateral parking position to directly in front of the light source. As a result, the direct dazzling effect of the light beam is reduced and somewhat better spatial illumination is achieved.
Nevertheless, the fact that the LEDs produce a more or less broad light cone owing to their recessed position in the lamp housing, in spite of the front diffusing lens attachment, remains as a disadvantage. In addition, because the diffusing lens lies in a plane with the front of the lamp housing, the luminous efficiency is not optimal.
It is therefore an object of the present invention to provide a system which makes it possible for a commercially available portable lamp, in particular flashlight or helmet lamp, to be converted in a simple and economical manner to function as an effective camping light which offers considerable light diffusion in combination with maximum luminous efficiency and can therefore be used for uniform spatial illumination, predominantly at close range, for example in the interior of a tent or trailer.
This object is achieved by the diffuser attachment as described in claim 1. Further useful embodiments of the invention are defined in the dependent claims.
As shown in
Here, “sleeve” or “sleeve-like” indicates the generally elongated external shape of the housing open at one end. However, shapes differing therefrom, for example a spherical or cubic shape of the housing which if need be is multi-part and is always open at one end in the ready-to-use state, are also to be included according to the invention under these definitions.
In the simplest case, the diffuser attachment is used by inverting it loosely over a commercially available lamp, typically a flashlight or helmet lamp, but, for use outdoors, fixing to the corresponding lamp is advantageous. A lamp is to be understood here also as meaning a conventional incandescent bulb with associated holder or associated lamp socket, the expression incandescent bulb here being representative of all lighting means to be screwed into a holder or a socket and having an external thread, for example also for energy-saving lamps having a spiral fluorescent tube.
The first end 3 of the housing is that which, in the state mounted on a lamp ready for use, is opposite the light source at a predetermined distance dependent on the length of the housing. According to one embodiment of the present invention, it is equipped with a cap 8 which is inseparably connected to, for example integral with, the housing or optionally removable again and which firstly carries the reflector element 7 and secondly completely closes the housing at this point.
The reflector element 7 is connected firmly or detachably on the inside of the cap 8, which in the latter case permits the possibility of replacement in the event of damage. When the diffuser attachment is mounted ready for use on the lamp, the reflector element 7 is in any case opposite the light source 14 in such a way that the light beam or light cone emerging from the light source 14 strikes the convex surface of the reflector element 7 centrally and is reflected by this as far as possible uniformly in all directions.
In a special embodiment, the cap 8 may be composed of two parts and comprise a first, approximately annular part 8a, which carries the reflector element 7, and a second part 8b, which is in the form of a cover and is detachably connected via at least one connecting element, preferably a plug connector, to the first part 8a. This design makes it possible, inter alia, for the reflector element to be removed, cleaned or economically replaced in the event of soiling or any damage.
The detachable connection between the one- or two-part cap and the housing can be effected in various ways, for example by a fast-action coupling, such as, for example, a snap, clamp, screw or plug connector.
For use with commercially available flash lights or helmet lamps, the open end 4 of the diffuser attachment according to the invention is tailored to the geometry and dimensions of said lamps. Here, flashlights are to be understood as meaning substantially rod-like flashlights.
In the simplest application of the present invention, the portable lamp, in particular flash light or helmet lamp, is a model which can be placed so that it is at least to some extent stable and in any case stands by itself on a flat surface and can emit its light perpendicularly upward. In order to achieve diffuse, spatial and anti-dazzle illumination of the relatively close environment, it is possible to use a diffuser attachment according to the invention which has, at the end 4, an internal diameter which exceeds the greatest external diameter of the lamp and can therefore be loosely inverted over said lamp.
For most applications, however, it is preferable if the diffuser attachment according to the invention can be fixed to the lamp reversibly, i.e. in a removable manner, in order to permit the use thereof in any desired position of the lamp, i.e. for example also when suspended.
For this purpose, it is intended for the diffuser attachment to have, in the base region 6 of its open end 4, fixing means which cooperate with corresponding fixing means of the lamp and which make it possible to connect it reversibly to the lamp, for example in the manner of a fast-action coupling, in particular a snap, clamp, screw or bayonet coupling.
In one embodiment for a helmet lamp having an oval or rectangular cross-section of the lamp socket, the diffuser attachment according to the invention is adapted to the lamp geometry so that it can be inverted over the top of the helmet lamp on the light exit side and can be connected to said lamp by gentle pressing until a snap fastening mechanism is overcome. In this case, the cooperation of the diffuser attachment with the lamp socket takes place via corresponding edges and projections or abutments and barbs, as shown in the figures (
If the sleeve of the housing 2 is in two parts, it can, depending on the embodiment, for example with or without a hinge at the end 3, also be placed on a flange region of the lamp socket and firmly clamped in a stable manner and fixed on the lamp socket, for example by means of at least one clamp coupling. At the other end 3, the housing halves can be held together either by the hinge or, for example, by plug or snap couplings.
In order to achieve as high a luminous efficiency as possible and good diffusion of the light, the distance between the light source 13 integrated in the lamp 9 and the reflector element 7 should be at least 1 cm when the diffuser attachment is positioned ready for operation. As a rule, this distance is about 1 to not more than about 20 cm, but a diffuser attachment whose length gives a distance from the reflector element to the light source in the range of about 5 to 10 cm is sufficient for most applications. On switching on the light source 13, which generally consists of one or more LEDs but of course may also comprise a conventional incandescent bulb, the directed light beam is deflected by the reflector element 7 in lateral directions, passes through the transparent or translucent, for example opal glass-like, walls of the housing 2 and thus produces a diffuse, uniform and anti-dazzle illumination of the environment.
Although the diffuser attachment according to the invention is shown and described by way of example below in detail for use with a helmet lamp, it is evident to the person skilled in the art in this area, directly and without an inventive step, from his knowledge in conjunction with the following description, that the fundamental principles of the invention can also be applied to the use with other portable lamps, in particular flashlights, and optionally also lighting means with fixed mounting, for example freely suspended lighting means, such as incandescent bulbs and fluorescent lamps, and how said fundamental principles can be applied.
The open end 4 of the housing, which typically has a rectangular, rectangle-like, oval, ellipsoidal or similar, in particular polygonal, optionally also round, cross-section, can be formed so as to be approximately complementary to the shape of a saddle for the purpose of detachable fastening of the diffuser attachment on a helmet lamp, with recesses on the broad side in the form of an upside down “U” and, on the long side, drawn-out side parts of the housing (cf.
In order to ensure that the diffuser attachment rests in a stable manner on the helmet lamp, according to a preferred embodiment the housing 2 has, in the base region 6, at a predetermined distance from the lower edge of the open end 4 of one of the two longer side parts, at least one inward-facing first projection 12 (cf.
Where the term “upper side” or “light exit side” is used here in association with the helmet lamp, that side which has the exit opening for the light beam is meant thereby.
On that side of the housing wall which is opposite the first projection, the housing may have a further, inward-pointing, second projection 14 which cooperates in the manner of a fast-action coupling, for example of a snap coupling, with another edge on the upper side or a lateral region of the helmet lamp and detachably fixes the housing in this manner to the helmet lamp, said second projection 14 typically not being at the same height as said first projection.
Of course, the fast-action coupling may also have any other suitable form, for example the form of a groove which runs all round the lamp and into which the end 4 of the housing can be inserted to form an interlocking connection and can be held either by a clamping action or once again via a snap coupling mechanism. Particularly for lamps having a round cross-section, diffuser attachments according to the invention which, at their open end 4, have a round cross-section with an internal or external thread in the base region 6 and can be screwed onto the lamp with corresponding opposite thread are provided—as already mentioned further above. Bayonet couplings are also suitable, the open end 4 of the housing having, for example, an outward-directed collar positioned on at least one section, preferably on at least two sections, and being capable of being turned therewith into a corresponding retaining rail on the lamp and being firmly clamped or optionally fixed via a snap mechanism. In a simple but universally applicable embodiment, the diffuser attachment is adapted in the region of its open end 4 to the lamp equipped therewith in that, in this region, it at least approximately follows the outer contours of the lamp base, of the lamp holder or of the lamp socket and, in this region, has the broadest diameter, which is either slightly smaller than, equal to or greater than the corresponding largest diameter of the lamp base, lamp holder or lamp socket. In the case of a smaller diameter, the diffuser attachment can be pushed onto the lamp easily with application of pressure and is then firmly held there by a clamping action. For this purpose, it consists of an at least slightly extendable material, for example a suitable plastic material. If the open end 4 has the same diameter as or a larger diameter than the lamp base, lamp holder or lamp socket, the housing of the diffuser attachment can be completely inverted over the lamp and then fixed to the lamp base, lamp holder or lamp socket by clamping, for example by means of one, two or more adjusting or set screws mounted on the side of the housing. For this purpose, the lamp requires no opposite thread since the adjusting or set screws have external threads and are guided in corresponding openings in the region of the open end 4 of the diffuser attachment, which openings are provided with internal threads. These set or adjusting screws may be produced from a suitable plastic material and, for easier handling, have ribbed screw heads or screw heads equipped with small wings. Instead of the screws, however, it is also possible in principle to use spring-loaded clamping pins or bolts with a snap-in mechanism.
In addition, the diffuser attachment according to the invention, can, as shown in
The housing itself is typically produced from a transparent or translucent, preferably an impact-resistant and scratch-resistant, colorless or colored plastic but may also consist of such a glass, especially toughened glass.
In a particular embodiment, the diffuser mirror of the reflector element 7 may also have one or more, optionally slot-like, openings 15 through which a part of the light of the light source can pass and, for example, can illuminate a colorless or colored, transparent or translucent region in the cap 8 so as to be visible from the outside. Thus, a region may be, for example, in the form of lettering and/or a logo of the manufacturer.
| Number | Date | Country | Kind |
|---|---|---|---|
| 00929/09 | Jun 2009 | CH | national |
