WO1992014644A1

WO1992014644A1 - Lamp and cooperating bracket

Info

Publication number: WO1992014644A1
Application number: PCT/DK1992/000048
Authority: WO
Inventors: Preben Bisgaard; Bjørn BISGAARD
Original assignee: Preben Bisgaard; Bisgaard Bjoern
Priority date: 1991-02-18
Filing date: 1992-02-17
Publication date: 1992-09-03
Also published as: AU1321092A; EP0572496A1; DK20092A; DK20092D0

Abstract

A lamp (1) of the kind which in a detachable way immediately may be mounted by simple mechanical engagement with a separate lamp bracket (13, 14), which may be mounted on a bicycle, comprises an electronic circuit in which one or more light emitting diodes are connected with one or more lithium batteries through a switch which may be controlled by an external magnet. The lamp bracket (13, 14) cooperating with the lamp (1) is constructed of or contains a permanent magnetic material or a material which may be permanently magnetized.

Description

Title: Lamp and cooperating bracket

The present invention concerns a novel lamp of the kind which in an detachable way may immediately be mounted on a bicycle, and a coopera- ting novel lamp bracket.

From Danish accepted patent application No. 160,003 is known a light source to be used as a warning signal, preferably to be used as a rear light on a bicycle. Said light source comprises at least one light emitting diode, an electronic circuit for generating current pulses to the light emitting diode and a current coupler. Besides, the prior art light source comprises a housing with a plane face on which the light emitting diode is located. The electronic circuit known from the accep¬ ted application mentioned is arranged so as to function at a frequency in the frequency range of about 24 Hz to 40 Hz. The current coupler is constructed in such a way that the curcuit is switched on or switched off by a touch or a short-circuiting of at least two contact points located on the housing. It is stated that the light source disclosed in the accepted application is using dry cells as a source of current, though alternatively it is stated that the light source may function with a rechargeable battery or an accumulator. The disadvantage of dry cells, rechargeable batteries and accumulators is partly selfdischarge, partly the discharge characteristic. Danish accepted application No. 160,003 does not disclose any solution to the first-mentioned problem, but regarding the discharge characteristic said problem is remedied by incorporating in the electronic circuit a current control circuit for keeping the current in the pulses to the light emitting diode or diodes at a constant level .

From published German patent application No. 3,834,554 is known an emergency lamp to be used in mining, said emergency lamp containing as current supply lithium cells which are connected to a filament lamp via a circuit comprising a switch. By using lithium cells in the emergency lamp it is secured that the degree of self-discharge is low, but on the other hand, the combination of lithium cells and a filament lamp as a light source results in a very restricted service life. Published German application No. 2,310,377 discloses a contact-free switch or circuit changer for electronic circuits. In the switch or the changer an electrically conductive permanent magnet or a permanent magnet provided with an electrically conductive surface is serving as the contact creating part which is affected from the outside with a ferro magnetic material.

Published German patent application No. 3,827,306 discloses a water proof switching arrangement for electric appliances. This switching arrangement comprises a double chamber-magnetic switch inserted between an electric hand tool and its electric mains connection. One chamber is hermetically sealed and comprises magnetically affectable contact springs, which in the closed position connect the electronic hand tool with the electric mains connection. In the unaffected state the contact springs are in the open position. The second chamber comprises a spring suspended magnet, which via an externally manipulated device can be brought from a first position defined by the pretension of the spring to a second position, where the magnetically affectable contact spring is brought into the closed position. Published British patent application No. 2,026,791 discloses a dynamo-l ghting system comprising at least one lamp and an AC generator for supplying current to the lamp and a current rectifier disposed between the generator and the lamp, in which dynamo-l ghting system the lamp is connected to the rectifier through a resistor, the lamp and the resistor form a first circuit, a rechargeable battery reserve is connected to the rectifier through a control switch, and the battery reserve and the control switch form a second circuit in parallel with the first one. It is stated that the switch may be a magnetically operated reed switch. The dynamo-lighting system disclosed in this Bristish patent specification is, in the latter embodiment, pivotally connected with a magnet, and the dynamo-lighting system as well as the magnet p votally connected therewith are not of the type which may immediately be mounted in a detachable way on a bracket as is the case with the lamp according to the invention. On the contrary, the mounting of the dynamo-lighting system and the magnet connected therewith demands a very exact adjustment in order that the battery reserve will function. Furthermore, the dynamo-lighting system disclosed in published British patent application No. 2,026,791 suffers from the same disadvantages as all dynamo lamps, viz. tyre wear, bad or no performance in rain or snow and bad mechanical and electrical durability because of the placing on the bicycle being exposed to moisture and salt and dirt from the road. The battery reserve will also be used rapidly if the dynamo-lighting system is not released when parking the bicycle. The prior art lamps which may immediately be mounted in a detach¬ able way suffer from a number of disadvantages as they have a short service life in relation to weight and size, show inappropriate dis¬ charge characteristics or self-discharge, loss of effect in cold weather and/or have a complicated design which makes the production thereof difficult.

It is the object of the present invention to provide a lamp which in a detachable way immediately may be mounted on a bicycle, the lamp being of a simple construction, having a low weight and small size in relation to service life, and showing essentially constant discharge characteristics, low self-discharge and low effect sensitivity to cold. In accordance herewith there is provided a novel lamp of the kind which in a detachable way may immediately be mounted by simple mecha¬ nical engagement with a separate bracket which may be placed on a bi- cycle, which lamp comprises an electronic circuit, in which one or more light emitting diodes are connected with one or more lithium cells through a switch which may be controlled by means of an external magnet.

Furthermore, according to the invention there is provided a novel bracket cooperating with the lamp according to the invention, said bracket being of the kind which is mountable on a bicycle, and being made from or containing a permanent magnetic material.

The lamp according to the invention consists of far fewer parts than e.g. the lamp according to Danish patent specification No. 160,003 and has a service life which is at least a tenth power longer than the service life of the emergency lamp for use in mining according to published German patent application No. 3,834,554. Because of the novel design of the lamp according to the invention it has surprisingly been possible in relation to the prior art to reduce the weight and the size hereof obtaining at the same time a surprisingly high ratio between service life and weight. Furthermore, the lamp according to the invention does not suffer from the prior art problems consisting in leakage from electric cells, functional problems as a result of climatic conditions, including cold and damp weather, decreasing battery voltage during use, self-discharge of the battery and/or unintentional use of battery capacity.

A preferred embodiment of the lamp and bracket according to the invention is described in the following with reference to the drawings wherein Fig. la is a perspective view of the lamp in unassembled form, Fig. lb is a perspective view of the lamp in assembled form, Fig. 2a is a top view of the lamp housing (1), Fig. 2b is a bottom view of the lamp housing (1), Fig. 3 is an axial section view of the lamp housing (1), Fig. 4a is a top view of the electronic disc (2), Fig. 4b is a bottom view of the electronic disc (2), Fig. 5 is a perspective view of the lamp bracket in unassembled form, and Fig. 6 is a view of the lamp bracket in assembled form mounted with the l mp.

With reference to fig. la a preferred embodiment of the lamp according to the present invention is shown in unassembled form. The main components comprise a lamp housing (1), an electronic disc (2), a spring (3), and a lamp glass (4), preferable in the form of a reflector. From fig. la it is seen that a light emitting diode (5) is mounted on the electronic disc and that the disc (2) comprises an opening (6).

Fig. lb depicts the lamp from the same visual angle as in fig. la but in the assembled form. From fig. 2a it appears that the housing (1) internally at the bottom is provided with a guide pin (7) which by engagement with the opening (6) in the electronic disc (2) causes the disc (2) to be placed in an functionally correct way. The spring (3) is arranged so as to retain the disc (2) against the interior bottom of the housing (1) and at the same time retain the lamp glass (4) against a non-depicted inwardly directed collar along the upper edge of the housing (1).

Fig. 2b depicts the housing (1) seen from the bottom which com¬ prises a recess (8).

Fig. 3 depicts an intersected housing (1) comprising the guide pin (7) and the recess (8). The recess (8) is shaped in such a way that the bottom of the housing (1) protudes over the recess (8) along the edge thereof to form a collar which is arranged so as to be able to engage with cooperating grooves in the bracket.

Fig. 4a and 4b depict the electronic disc (2) seen from above and from below, respectively. The first connection of the light emitting diode (5) is placed in contact with the first terminal of a lithium battery (10), and the second connection of the diode (5) is connected at (9) to the first connection of the magnet switch (11). A second connection (12) of the magnet switch (11) is connected with the second terminal of the lithium battery (10).

Fig. 5 depicts a perspective view of a preferred embodiment of the lamp bracket in unassembled form. The lamp bracket comprises a part (13) which through grooves (19), of which only one is shown, is adapted so as to engage with the recess (8) at the bottom of the lamp housing. Furthermore, the bracket comprises a part (14) which is adapted so as to be retained to the part (13) with screws (15) in such a way that the parts (13) and (14) surround a tubular part of a bicycle, and through cooperating grooves (17) and (18) are retained in an essentially hori¬ zontal position. The screws (15) which unite the parts (13) and (14) pass through openings (16a) and (16b).

With reference to fig. 6 a sideview is shown of bracket parts (13) and (14) in assembled form around a tubular part (20) of the bicycle. The embodiment illustrated in fig. 1-4 of the lamp according to the invention is shown in a mounted position on the bracket part (13). The part (13) of the lamp bracket is either provided with an built-in permanent magnet or is in itself formed of a magnetic material.

When the recess (8) of the lamp is engaged with the grooves (19) of the bracket part (13), the lamp is turned on by the activation of the magnet switch (11) whereby the current to the light emitting diode (5) is switched on. Conversely, the lamp is automatically turned off when it is removed from the bracket.

The lamp housing (1), the electronic disc (2) and bracket parts (13) and (14) are preferably formed in totally or partially transparent or non-transparent plastics which may be stained or unstained. The lamp glass (4) is formed of transparent, unstained or stained preferably red colored plastics.

The magnet switch (11) is preferably a reed switch which is herme- tically enclosed in a glass or plastic tube.

The lithium battery (10) may e.g. be of the type RENATA CR 2430 with a terminal voltage of 3 V. As an example of the light emitting diode (5) HIGH BRIGHT LED TU181 may be mentioned. In the embodiment shown a service life of about 400 hours is obtained. It will be appreciated by a person skilled in the art that diffe¬ rent variations of the above embodiment may be provided without diffe¬ ring from the scope of the invention.

Claims

Patent claims

1. A lamp of the kind which in a detachable way may immediately be mounted by simple mechanical engagement with a separate lamp bracket which may be mounted on a bicycle, CHARACTERIZED in comprising an elec- tronic circuit in which one or more light emitting diodes are connected with one or more lithium batteries through a switch which may be con¬ trolled by an external magnet.

2. The lamp according to claim 1, CHARACTERIZED in that the magnet switch is a reed switch.

3. The lamp according to claims 1-2, CHARACTERIZED in comprising a single 3V lithium battery and a single light emitting diode.

4. The lamp according to claims 1-3, CHARACTERIZED in that the light emitting diode is a red light emitting diode.

5. A lamp bracket cooperating with the lamp according to claims 1-4 and being of the kind which may be mounted on a bicycle, CHARACTERIZED in that it is constructed of or contains a permanent magnetic material or a material which may be permanently magnetized.

6. The lamp bracket according to claim 5, CHARACTERIZED in that it is formed of a composit of plastics and magnetic material.