GB2165977A - Naval rescue optical signalling device - Google Patents

Abstract

A flashlamp (5), a generator (6) connected thereto for generating light pulses and a current supply source (10) are protected from moisture by housing portions (1,2,3) the flashlamp and the generator being completely embedded in an at least partially translucent potting material forming a lamp housing. The device is provided at its outer surface with contacts 7 to be contacted by water for closing a current circuit of the current supply. The housing portion 3 for the current supply source may be integral with the lamp housing as shown or connected thereto by cable. <IMAGE>

Description

SPECIFICATION A signalling device acting optically for indicating a position in particular for rescue purposes BACKGROUND OF THE INVENTION 1. Field of the Invention The invention concerns an optically acting signalling device for indicating a position, in particular for rescue purposes, comprising a flashlamp (tube) and a generator connected thereto tor generating light pulses as well as a current supply source in the form of batteries, accumulators or the like, the flashlamp, the generator and the current supply source being protected from humidity by means of a housing or housing elements.

2. Prior Art Various signalling devices or lighting equipment having blinkers are presently being used for naval rescue purposes, which devices can be attached to life-vests or -jackets. In these devices a housing carries a metal switch which generates the blinking effect. Particularly in cases of rough sea, bad visibility or other unfavourable weather conditions, which will normally be met in cases of emergency at sea, such signalling devices have proved unsatisfactory due to their rather reduced luminous intensity so that the blinking will not be easily perceptible. In normal devices the energy for lighting the lamp is generated by a separate battery activated by sea water. Such batteries are special batteries which can normally only be obtained through specialized dealers dealing with naval requisites.Such batteries can hardly be tested regularly for their effectiveness because the activation by sea water causes a chemical process which is not reversible and can thus only be carried out once so that the function of the special battery cannot be restored after testing.

Another known optically acting signalling device (US Patent 3 798 692) includes a power supply and switch assembly with a lamp to be secured to a life preserver. The bottom of the switch assembly is provided with a perforated cover, which closes a housing in which a flexible switch diaphragm is arranged. The switch assembly includes a movable bridging contact which can be brought into bridging engagement with stationary contacts of a current circuit. When water floats into the space covered by the cover, the pressure in this space is increased and the diaphragm moves upwardly to bring the bridging contact into the short-circuit position for the current circuit.

Since the perforations of the bottom cover are significantly below the diaphragm, the diaphragm will be isolated from the water by a trapped air pocket, so that the diaphragm cannot be affected by salt water and will thus not be exposed to corrosion. The switch thus merely works due to water pressure, i.e. the switching can only be achieved when the assembly is immersed into water, and the function of the lamp will only be maintained as long as this immersed position is maintained.

Furthermore, flash buoys are being used in practice which are thrown overboard in a case of emergency (e.g. man-overboard) in order to mark a certain position. These flash buoys are rather voluminous and cannot be attached to life-vests. This is the reason why they are normally attached to life-belts. They comprise a battery which generates the ignition voltage of approx. 1 500 V and the working voltage of approx. 300 V on the anode/cathode of a flashlamp. The flashlamp normally has the shape of a flash tube and is arranged in a hollow body which is closed by a spherical or dome-shaped cover. This closed space easily and quickly leads to the development of condensation water which reduces the function of the device or even makes this completely inoperative, because humidity, on the one hand, and the necessary high voltages, on the other, are not compatible.The humidity will lead to the creation of leakage paths and thus to an undesired energy consumption.

Another known signalling device (US Patent 4 099 282) has the form of a floatable rescue light beacon, which may be tethered to a life ring. The beacon comprises an electronic strobe light, an associated electronic circuitry (generator) and an electrical power source.

which elements are housed in a sealed transparent cover and thus protected from water getting into contact with them. However, the transparent cover encloses a hollow space, in which condensation water will develop. This condensation water development is favoured due to rather high temperature differences caused by the surrounding condition, i.e.

water and air contact. Again, the condensation water will lead to the building up of leakage paths, and furthermore moisture will precipitate at the inside of the cover so that the light intensity is affected and the perceptible light intensity reduced. Furthermore, the electronic strobe light and the associated electronic circuitry arranged in the hollow spaced are susceptible to vibration and shaking. Following mechanical stressing, in particular by shocks or vibrations of- vessel engines, stable mounting of these elements cannot be safeguarded over a long period, so that the functional reliability of this device will be affected.

The strobe light and the electronic circuitry are arranged at the upper end of a narrow hollow pole, which also carries a floatation collar at an intermediate position along its length and a container mounted suspended from the bottom of the pole, within which container a power source is housed. The strobe light is activated by a magnetic reed-type switch mounted in the container, which switch is operated as soon as the container is removed from its holder on board a vessel. Inside the pole there is arranged the conductor for conducting it from the container to the strobe light and electronic circuitry. This device is rather bulky and not capable of being secured to a life-vest.

3. Objects of the Invention It is an essential object of the present invention to suggest an optically acting signalling device for naval rescue purposes in which the housing not merely protects the flashlamp and the generator circuitry from moisture but rather forms a massive body without any hollow space. It is another object of the invention to provide such a body having a compact and small structure and being secure against mechanical, electrical and electro chemical destruction. It is still another object of the invention to safeguard the emission of flashlamp light which is not influenced by the structure.

According to yet another object of the invention, a signalling device is suggested which enables a regular checking of the ability of function and safeguards the operation of the flashlamp as soon as it gets into contact with water by rather simple structural measures completing the compact isolated overall structure of the device.

SUMMARY OF THE INVENTION In an optically acting signalling device comprising a flashlamp, a generator circuit electrically connected to the flashlamp for generating light pulses, and a power supply source in the form of batteries, accumulators or the like, wherein the flashlamp, the generator and the power source are protected from moisture by housing elements which are translucent at least in the region of the flash lamp, the above objects are achieved in that the flash lamp and the generator circuit are completely embedded in a potting material forming the housing and that the device carries on its out side electrical contacts to be contacted by water and thus short-circuiting the electrical circuit connecting the power supply source, the flashlamp and the generator circuit.The main advantages obtained thereby are that the flashlamp and the high voltage generator means are hermetically sealed against humidity and thus completely independent of the sur rounding moisture and that they are arranged in a small and compact housing body, in which these elements, which are essential for the correct function of the device, are not subject to exterior influences such as blows, percussion or vibration. The housing body, made from potting material, preferably synthetic resin such as acrylic glass, can be handled easily due to its compact, solid and integrated structure and is translucent so that the flashes generated in the lamp can be emitted from the device without any losses, i.e.

they have a high luminous intensity. They are much more intensive and perceptible over essentially longer distances even in the cases of bad weather and heavy sea than a normal blinker device. On the other hand, the flashlamp will have a rather long life because of its low temperature rise and its short-time actuation. Furthermore, the device according to the invention enables the application of normal batteries, which are considerably cheaper than special batteries to be actuated by salt water, whereas the sea water merely serves for activating the contacts thus closing the electrical power supply circuit and does not initiate any chemical process as in certain known signalling devices. The flashlamp will work at its fuli light intensity until the voltage of the battery or accumulator breaks down completely.

According to an advantageous embodiment of the invention, the flashlamp and the generator circuit may be embedded in separate potting material bodies which can be attached to each other easily. The advantage of the embodiment is that the flashlamp must be potted in a transparent or translucent material in order to safeguard its function, whereas no such transparency or translucence is necessary for the generator, so that a cheaper material may be used.

In order to be able to use the signalling device easily on life-vests, it may be considered expedient to provide the flashlamp and the generator circuit in one potting material unit and connect them via a conductor with the power supply source arranged in a separate housing unit. Thus the effective light element can be secured to those parts of the human body which will normally be in an upper position in the case of naval emergency, e.g. the shoulder area, while the power supply source with its housing portion and the contacts can be secured to a lower portion, e.g.

at the level of the waist, which will then be in the water so that a short-circuiting of the circuitry means will be safeguarded. However, it may be desirable and expedient to provide the device in one piece, in which case it is preferable to provide that the potting material unit comprising the flashlamp and the generator circuit can be assembled into one piece with the housing portion for the power supply source, this housing portion merely necessitating a detachable cover in order to enable a quick exchange of the batteries, accumulators or the like.

A particularly advantageous arrangement of the signalling device provides for a sensorcircuitry on one of the housing portions including moisture sensitive sensors, the sensor-circuitry including at least one IC and or one transistor which are turned on when contacted or charged by moisture and close a battery circuit for the current supply of the generator.

Such moisture sensitive sensors enable a quick short-circuiting of the battery circuit via the integrated circuit, the generator being con trolled by the turning-on of the transistor. A breaking of this short-circuit is only possible by removing the battery. This, on the one hand, safeguards that the device is actuated immediately upon closing of the contacts, i.e.

when a contact with water occurs without the person carrying the device needing to take any influence thereon, whereas, on the other hand, a checl < ing of the device is possible at any time without necessitating an exchanging of the batteries after one single use as occurs in the case of known chemically effective sea water batteries. As already mentioned above, the flashlamp works at full light intensity until the complete breakdown of the battery voltage so that there is no reduction in light intensity as in the known blinking devices.

In order to simplify the structural elements further and provide a very practical arrangement, the housing portion comprising the current supply source may consist of stainless steel and form a sensor.

BRIEF DESCRIPTION OF THE DRAWINGS Other and further objects of the present invention will be apparent from the following description and claims and are illustrated in the accompanying drawings, which by way of illustration schematically show preferred embodiments of the present invention and the principles thereof and what now are considered to be the best modes contemplated for applying these principles. Other embodiments of the invention embodying the same or equivalent principles may be used and structural changes may be made as desired by those skilled in the art without departing from the present invention and the scope of the appended claims.In the drawings Fig. 1 shows a signalling device according to the invention in an integrai arrangement, Fig. 2 shows another embodiment of the signalling device according to the invention in a two-piece arrangement and Fig. 3 shows a circuit diagram of the signalling device according to the invention.

DESCRIPTION OF THE PREFERRED EMBODI MENT As shown in Fig. 1 a signalling device comprises a housing which is composed of housing portions 1 for a flashlamp 5, 2 for a generator 6 and 3 for power supply sources such as batteries 10, which are not shown in Fig.

1. In order to be able to substitute the batteries depicted in the block diagram of Fig. 3 rather easily, the housing portion 3 is closed by a cover 4. The housing portion 1 for the flashlamp 5 consists essentially of a translucent potting material body, into which the flashlamp 5, which has the form of a flash tube, is completely embedded so that it is arranged isolated against moisture or humidity in every respect. Sensors 7 are molded or potted in lateral positions of the potting material body forming the housing portion 1, which sensors have an outwardly free contacting area and are connected to the generator 6, which is a high voltage generator for the flashlamp 5 by means of non-shown conductors according to the block-diagram of Fig. 3.

The generator 6 is also completely embedded by potting in the respective housing portion 2, which is also a potting material body, which embedding is effected as has been described with respect to the unit housing portion 1/flashlamp 5 so that these elements are hermetically sealed against humidity and no condensation water can develop inside the housing. The potting material body forming the housing portion 2 need not be manufactured from translucent or transparent casting resin, but it can be made of any appropriate and cheaper material. This housing portion 2 for the generator 6 is formed slightly conically, whereby an appropriate connection to the housing portion 3 for the battery 10 is possible and the three housing portions can be assembled easily to a one-piece unit.

In this embodiment the sensor 7 is provided as an element surrounding the housing portion 1 and embedded into the potting material of the latter. This sensor 7 forms one of two switch contacts, the second one being formed by the housing portion 3, which, to this end, consists of stainless steel.

The signalling device shown in Fig. 2 differs from that of Fig. 1 essentially only in that it is provided in two pieces, i.e. the housing portions 1 and 2, on the one hand, and 3, on the other, and by the arrangement of the sensors 7. While the signalling device of Fig. 1 can be secured as a single unit by non-shown securing means at any position of a life-preserver, live-jacket, safety belt but also on a helmet or similar equipment to be carried on the human body at an appropriate position, the housing portion 3 of the device according to Fig. 2 is normally secured to a life-jacket somewhere in the region of the waist or hip and connected to the housing portion 1, which in this case comprises the flashlamp and the generator with the necessary circuit via a battery wire or cable 9.The housing portion 1 can be secured to a life-vest somewhere in the region of the shoulder by appropriate securing means not shown. In the case of naval emergency the two sensors 7 will be in the water due to their arrangement on the battery housing portion 3 and will be shortcircuited so that the device will be initiated through a moisture sensor switch 8, which is arranged in the region of the two sensors 7.

The battery voltage is supplied to the functional elements enclosed in the potting material unit 1 and 3, respectively, such as generator 6, storage capacitor 11, ignition contact 12 and sweep generator 13 via the battery wire 9 in order to generate a flash light of high light intensity at the usual intervals.

Of course, the housing portion 3 for the batteries 10 may have any appropriate shape which will normally be dependent on the shape of the batteries to be used.

The circuit-diagram shown in Fig. 3 partially reflects the elements already shown in Fig. 1 and 2 such as the moisture sensor switch 8, to which the sensors 7 are associated (not shown in this place), battery 10, generator 6 and flash light 5. Beyond these elements the circuit comprises a storage capacitor 11 for the generator 6 as well as an ignition contact 12 and a sweep generator 13 for the flash light 5. When the moisture sensor switch 8 is charged or initialised, i.e. in the case of an activation between the sensors 7 due to an immersion of the device in water, an IC and a transistor comprised by the sensor switch 8 turn on and close a circuit for the generator 6, by which the charging of the flashlamp 5 via the sweep generator 13, the ignition contact 12 and the storage capacitor 11 is initialised so that the flashlamp works either till the voltage of the battery 10 breaks down completely or the battery is removed.

Claims (7)

1. A signalling device acting optically for indicating a position, in particular for rescue purposes, the device comprising a) a flashlamp, b) a generator circuit electrically connected to the flashlamp for generating light pulses, c) a power supply source, d) circuitry means for electrically connecting the power supply source, the flashlamp and the generator circuit with each other, e) a housing surrounding the flashlamp, the generator circuit, the power supply source and the circuitry means in a manner to protect them from humidity, at least part of the housing being formed by a potting material completely embedding the flashlamp and the generator circuit and being translucent at least in the region of the flashlamp, and f) electrical contact means forming part of the circuitry means and arranged on the outside of the device in a manner to be contacted by water and thereby to close the circuitry means to supply electrical current from the power source to the generator circuit and flashlamp.

2. Signalling device as claimed in claim 1, wherein the flashlamp and the generator circuit are embedded in one separate potting material portion each, which portions are easily attachable to each other.

3. Signalling device as claimed in claim 1 or 2, wherein a first housing unit embedding the flashlamp and the generator circuit is connected to a second housing unit arranged separately from said first unit by means of an electrical conductor wire.

4. Signalling device as claimed in claim 1 or 2, wherein a first housing unit embedding the flashlamp and the generator circuit is attachable to a second housing unit enclosing said power supply source to form a composite housing therewith.

5. Signalling device as claimed in anyone of claims 1 to 4, wherein the device comprises power supply circuitry means and sensor-circuitry means electrically connected with each other, said sensor-circuitry means comprising at least one humidity sensitive sensor as contact means, at least one IC and/or a transistor, which IC and/or transistor are turned on when said sensor is charged with humidity and thereby close said power supply circuitry means for supplying current to said generator circuit.

6. Signalling device as claimed in claims 4 and 5, wherein said second housing unit is made of stainless steel to formone of the sensors.

7. A device substantially as herein described with reference to the accompanying drawings.