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Title:
DISTRESS SIGNAL SYSTEM FOR SEA VESSELS AND A METHOD THEREFOR
Document Type and Number:
WIPO Patent Application WO/2021/201755
Kind Code:
A1
Abstract:
An emergency signal system for a sea vessel comprises several navigation lights (11, 12, 13, 14, 15), which are connected in an electrical circuit and arranged to emit a steady light in different directions in a normal operating state. The emergency signal system comprises a control means (28, 30) connected to the electrical circuit which in an emergency signal state is arranged to vary the current to the navigation lights (11, 12, 13, 14, 15) in order to vary the light emission therefrom in accordance with an emergency signal, such as SOS. A manually actuatable actuator (24) is connected to the control means (28, 30) to activate or deactivate the emergency signal state. A light activating means (26) is arranged to provide a varied power supply to the navigation lights (11, 12, 13, 14, 15) in connection with activating the emergency state, regardless of whether these are in operating state or not. Such an emergency signal system can be provided by connecting a separate emergency signal unit comprising a control means to the navigation lights of a sea vessel.

Inventors:
WESTH PETER (SE)
Application Number:
PCT/SE2021/050275
Publication Date:
October 07, 2021
Filing Date:
March 26, 2021
Export Citation:
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Assignee:
WESTH PETER (SE)
International Classes:
G08B5/38; B63B45/04; H05B39/04; F21S10/06; G08B23/00
Attorney, Agent or Firm:
HANSSON THYRESSON AB (SE)
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Claims:
CLAIMS

1. An emergency signal system for sea vessels comprising two or more navigation lights (11, 12, 13, 14, 15), which are interconnected in an electrical circuit and ar ranged to emit a steady light in different directions in an operating state, character- ized in that the system further comprises: a control means (28, 30) connected to the electrical circuit, which control means is arranged to vary the current to the navigation lights (11, 12, 13, 14,

15) in an emergency signal state in order to vary the light emission therefrom according to a pre-programmed pattern for formation of a well-established emergency signal, preferably in accordance with the Morse code for SOS, a manually actuatable actuator (24) comprising a switch connected to the control means (28, 30) for activating or switching off the emergency signal state by activating or switching off the control means (28, 30), and - a light activating means (26) coupled to the electrical circuit, which light acti vating means is arranged to provide, when activated, a power supply of said varying current to said navigation light, in connection with activation of the emergency condition, regardless of whether said navigation light is in operat ing state or not.

2. The emergency signal system according to claim 1, wherein the actuator (24) is arranged to be activated in response to an alarm signal from a detector indicating an emergency condition. 3. The emergency signal system according to claim 2, wherein the actuator (24) fur ther is connected to a preventing means for preventing accidental activation of the actuator.

4. The emergency signal system according to any one of the preceding claims 1-3, comprising an indicator (25) for indicating when the system is in an emergency sig nal state.

5. The emergency signal system according to claim 4, wherein the indicator (25) is a light indicator arranged to vary in accordance with the light of the navigation lights, the light indicator preferably being electrically connected to the navigation lights (11 , 12, 13, 14, 15) to confirm with its light the function of the system in emergency sig nal condition.

6. Emergency signal unit intended for sea vessels having two or more navigation lights (11, 12, 13, 14, 15) interconnected in an electrical circuit and arranged to emit a steady light in different directions in an operating state, characterized in that the emergency signal unit has a body (40) with connection points (41 , 42, 43, 44, 45, 46) for electrical connection to the navigation lights (11, 12,

13, 14, 15) and that the emergency signal unit has a control means (30) attached to the body, which control means is arranged to vary the current to the navigation lights (11, 12, 13, 14, 15) in an emergency signal state when the emergency signal unit is connected to the navigation lights in order to vary the light emis sion therefrom in accordance with a pre-programmed pattern to form a well- established emergency signal, preferably in accordance with Morse code for SOS, that the emergency signal unit further has a manually activatable actuator (24), which comprises a switch connected to the control means (28, 30) for activating or switching off the emergency signal state by activating or switch ing off the control means (28, 30), and that the emergency signal unit further has a light activating means (26) con nectable to the electrical circuit, which light activating means is arranged to provide, when activated, power supply of said varying current to said naviga tion lights, in connection with activation of the emergency state, regardless of whether said navigation lights are in the operating state or not.

7. The emergency signal unit according to claim 6, wherein the actuator (24) prefer- ably is arranged in a separate physical unit (29), and wherein the unit preferably also comprises an indicator (25) for indicating when the system is in an emergency state.

8. Sea vessel comprising an emergency signal system according to any one of the preceding claims 1-5 or an emergency signal unit according to any one of the pre- ceding claims 6-7.

9. A method for indicating sea distress on a sea vessel, wherein navigation lights on the vessel are caused to emit a pulsating light, preferably in accordance with the Morse code for SOS, by means of an emergency signal system according to any one of the preceding claims 1-5 or an emergency signal unit according to any one of the preceding claims 6-7.

Description:
DISTRESS SIGNAL SYSTEM FOR SEA VESSELS AND A METHOD THEREFOR

TECHNICAL FIELD The present invention relates to an emergency signal system, an emergency sig nal unit, a naval vessel provided with such a system or unit, and a method for indi cating an emergency situation on a naval vessel.

BACKGROUND Naval vessels, such as ships and boats of various kinds, have long used different navigation lights to make the vessel visible and to prevent collisions. The navigation lights used for this purpose are usually called lanterns. Both national and interna tional regulations regulate the design and use of navigation lights for different ships and in different situations. Ships have a green lantern on the starboard side and a red lantern on the port side, as well as different variants of white lanterns and all round lanterns depending on the type of vessel. Lanterns are intended to be used with a steady light in the dark and in poor visibility. Normally, they only have an acti vated, illuminated mode and an inactive, off mode.

In the event of distress at sea, there are various established signaling options such as radio signaling, sound signals, emergency rockets, hand flares and emer gency flags at hand. However, the known ways of generating sound and light signals have disadvantages as they require special equipment which must be retrieved in a distress situation and which must be handled manually. An example of this is shown in US 4,163,220 A, which describes a signal lamp for sea emergencies, which lamp is arranged to signal SOS with Morse code to nearby ships or land. This, and other similar solutions of the headlight type have, among other things, the disadvantage that one has to identify another ship and directly direct one-self towards it in order to attract its attention, since the emergency light is in principle only visible in one direc tion. US 2005/0225976 A1 describes a LED light network for ships with the possibility to control a number of different lightings on ships via a digital electrical network. Au tomatic control of different light effects in response to different input signals in the network is also described, for example it is stated that the exterior lighting of a ship can be made to flash in accordance with Morse code, as an automatic response to a signal in the network indicating an emergency. The solution is complicated and diffi cult to apply to smaller boats, which often lack exterior lighting. In addition, a digital network is required for the implementation of this solution. The network is also not suitable for use on existing sea vessels with an existing electrical circuit.

US 2007/0241937 A1 describes a system for controlling sound and light signals of a ship at limited visibility. The system comprises a control panel with a number of buttons and indicators and can initiate a number of different combinations of sound and light signals, including an SOS signal according to Morse code. However, in or der to put the system in an emergency state and send out emergency signals, a user must use several different pushbuttons and make a number of different keystrokes in

RECORD COPY TRANSLATION (Rule 12.4) sequence and also make a number of decisions, before an emergency signal is sent out. The system is intended to be connected to a lighting device with all-round white light, either an existing lighting device or a special separate lighting device, which also can serve as an anchor light. If the system is connected to an existing lighting device, which can also be switched on and off in another way, it must be ensured in the event of an emergency signal that this lighting is not switched on, otherwise no emergency signal will be emitted.

For situations in daylight, it is also possible to hoist emergency flags to call for help in the immediate area, but this is an extra step and has almost no effect in the dark. Furthermore, emergency rockets and hand flares have the disadvantage that they have a limited lighting time and are consumed during use. For emergency rock ets, which are visible from a distance, the problem also applies that, based on the rocket's position, it can be difficult to determine which of several ships are in dis tress, which can delay rescue operations.

The person in need is often busy with other things than calling for help. The ves sel may take in water and the leak must be located and stopped. Any fire must be extinguished, and any injured people must receive first aid. Someone may have fallen overboard and must be found and recovered. Every extra step to call for help in the immediate area in that situation may have fatal consequences.

External relief efforts that have been reached by an emergency signal of some kind and are on their way to a ship in distress, may have difficulty immediately distin guishing which of several surrounding ships is in distress.

SUM MARY

The object of the present invention is to solve problems with existing signaling systems for sea vessels in distress. In particular, the object of the invention is to pro vide a simply activatable signaling system for sea vessels in distress, which clearly indicates to a surrounding that a vessel is in distress, at the same time as the han dling thereof does not require large efforts from the crew of the vessel.

According to a first aspect of the invention, it is located in an emergency signal system for a sea vessel which has two or more navigation lights, which are intercon nected in an electrical circuit and arranged to emit a solid light in different directions in an operating state. The invention is characterized by a control means coupled to the electrical circuit, which control means is ar ranged to vary the current to the navigation lights in an emergency signal state in order to vary the light emission therefrom according to a pre-pro grammed pattern to form a well-established emergency signal, preferably the Morse code for SOS, a manually activatable actuator comprising a switch connected to the control means for activating or switching off the emergency signal state by activating or deactivating the control means, and a light activating means coupled to the electrical circuit, which is arranged to provide, when activated, a power supply of said varying current to said navigation light, in connection with activating the emergency state, regardless of whether said navigation light is in operating state or not.

This enables the existing navigation lights on a sea vessel, such as a ship or a boat, to be pulsed or flashed in a simple manner. Flashing signals are themselves a good way to attract attention visually, and flashing lights are intuitively interpreted as something deviating. By using the existing navigation lights, it is possible, at a very low extra cost, to create an easily observable light effect in all directions, as normal navigation lights together are omnidirectional and also visualizes the position and di rection of the distressed vessel. A further advantage of the invention is that the nor mal function of the navigation lights remains.

By emitting a well-established emergency signal by means of the navigation lights, it is further clarified to the surroundings that the ship transmitting the signals is in distress. It is particularly advantageous that the navigation lights are made to pul sate or flash in accordance with the familiar Morse code for SOS, i.e. three short, three long and three short flashes.

Thanks to the manually activatable actuator, an emergency signal can easily be started by someone in the ship's crew or even by a passenger, whereafter the emer gency signal continues for the time being by the navigation lights continuing to flash.

Thanks to the light activating means, the advantage is achieved that the naviga tion lights can be set in an emergency signal state regardless of whether the naviga tion lights previously are in operating mode, i.e., switched on, or in the deactivated mode. Preferably, all navigation lights are flashed, in connection with activation of the emergency mode.

In connection with the invention, the word sea/naval vessel refers to all boats and ships, regardless of size, propulsion technology and area of use. This refers to recre ational boats as well as passenger ships and merchant ships of various types.

The invention relates to use on sea vessels with several navigation lights, prefera bly two or more. Although the inventive concept can be applied to sea vessels with everything from one navigation light and upwards, it should be noted that greater benefits are achieved when used on ships with two or more navigation lights, partly because single navigation lights are only used on smaller recreational boats, partly since a better effect is achieved when more than one navigation light flashes, and not least since it is clear that the navigation lights belong to a sea vessel when green and red side lanterns also flash. In particular, the invention is intended for ships which, in accordance with national and international maritime regulations, must carry navigation lights.

The actuator according to the invention is arranged to be activated manually by the crew or passengers. However, it should also be noted that the actuator, within the scope of the inventive concept, also can be activated by a signal received from elsewhere, such as a signal indicating an emergency condition from a safety system on the sea vessel.

In a preferred embodiment, the actuator is further connected to a preventing means, intended to prevent unintentional operation of the actuator. The preventing means is arranged to prevent activation of the operating means during normal operation and must first be released to allow the actuator to be moved to the active position. This ensures that the actuator is not activated by mistake, in order to avoid that emergency signals are incorrectly transmitted.

In a further preferred embodiment, the emergency signal system has an indicator, such as a light indicator or a sound indicator, to indicate when the system is in an emergency signal state. This allows you to easily get confirmation that the emer gency signal state has been activated. Particularly advantageous is an embodiment in which a light indicator and/or a sound indicator is arranged to vary in accordance with the light of the navigation lights, as this also clearly illustrates the flashing func tion of the signal system. It is particularly advantageous that the indicator is electri cally connected to the navigation lights in order to confirm the function of the system in the emergency signal state with its light and/or sound. A light indicator is particu larly preferred.

According to a particular aspect of the invention, it relates to an emergency signal unit intended for a sea vessel, which has one or more navigation lights which are in terconnected in an electrical circuit and which are arranged to emit a steady light in different directions in an operating state. The emergency signal unit has a body with connection points for being electrically connectable to the navigation lights. Further more, the emergency signal unit has a control means attached to the body, which control means is arranged to vary the current to the navigation lights in an emer gency signal state, thereby varying the light radiation from these in accordance with a pre-programmed pattern to form a well-established emergency signal, preferably the Morse code for SOS, when the emergency signal unit is connected to the navi gation lights. The emergency signal unit further has a manually activatable actuator, which comprises a switch connected to the control means for activating or switching off the emergency signal state by activating or switching off the control means. In addition, the emergency signal unit has a light activating means connectable to the electrical circuit, which light activating means is arranged to provide, when activated, power supply of said varying current to the navigation lights, in connection with acti vation of the emergency state, regardless of whether the navigation lights are in op erating state or not.

By producing a separate emergency signal unit that is connectable to an existing navigation light system, the possibility of applying the invention on existing sea ves sels with navigation lights is advantageously enabled. Furthermore, the cost of im plementing the inventive concept can be kept low by producing separate emergency signal units for retrofitting on ships. A separate emergency signal unit according to the above also provides great advantages in new production, since navigation light systems and emergency signal unit can be manufactured separately and mounted separately, while working together after mounting on a sea vessel. This results in ef ficient production and installation.

It will be understood from the description above that all the advantages and func tions described in connection with the emergency signal system according to the in vention also can be reached with an emergency signal unit described above when it is connected to navigation lights on a sea vessel. In a preferred embodiment of the emergency signal unit, the actuator is advanta geously arranged in a separate physical unit so that the body and the actuator can be placed physically separated on the sea vessel. It is advantageous that the actua tor thus can be placed in a location where it easily can be activated manually, whereby the body can be placed in a location which is suitable from an installation perspective.

Furthermore, in a preferred configuration, the emergency signal unit also com prises an indicator for indicating when the system is in an emergency state. This unit is also advantageously arranged in a separate physical unit in relation to the body, such that it can be arranged in a location which is suitable for indicating when the system is in an emergency signal state and an emergency signal is transmitted. The actuator and the indicator may advantageously be arranged in a common physical unit.

According to a further aspect of the invention, it comprises a sea vessel having an emergency signal system or an emergency signal unit according to any of the above described aspects of the invention.

According to a particular aspect of the invention, it is a method for indicating sea distress on a sea vessel, wherein navigation lights on the vessel are caused to emit a pulsating light, preferably in accordance with Morse code for SOS, by means of an emergency signal system or an emergency signal unit according to any one of the above described aspects of the invention.

The inventive concept can also be described as the use of a sea vessel's naviga tion light to attract attention and indicate that the vessel is in distress at sea by flash ing these navigation lights, advantageously by signaling Morse code for SOS.

DESCRIPTION OF TH E DRAWINGS

In the following, the invention is described in more detail with reference to a pre ferred embodiment of the invention with reference to the accompanying drawings.

Figure 1 shows a wiring diagram for navigation lights on a sea vessel in accord ance with known technology.

Figure 2 shows a wiring diagram for a sea vessel equipped with a sea safety sys tem in accordance with the invention.

Figure 3 shows a wiring diagram for an emergency signal unit according to the invention.

Figure 4 shows an overview of an emergency signal unit according to the inven tion.

DETAILED DESCRIPTION OF AN EM BODI MENT

With reference to Figure 1, a typical installation of navigation lights on a sea ves sel in the form of a smaller vessel is briefly described below. The wiring diagram shows an electrical power source, here in the form of a 12 V battery 10, which is connected to and arranged to power the ship's navigation lights. The navigation lights, which follow Swedish and international maritime regulations, include in the ex ample two side lanterns, one port lantern 13 and one starboard lantern 14. The side lanterns 13, 14 are arranged to emit light sideways and forward, red light in a sector of 112.5° in the port and forward direction for the port lantern 13, and green light in a sector of 112.5° in the starboard and forward direction for the starboard lantern 14. The navigation lights further comprise a stern lantern 15 arranged to emit white light backwards and sideways in a sector of 135°. The lanterns 13, 14, 15 are connected in parallel with the battery 10 via a common switch 18 and a fuse 37. The circuit fur ther comprises a motor lantern 12, arranged to emit white light in the forward direc tion in a sector of 225° at motor operation. The motor lantern 12 is connected to the battery 10 via a separate switch 17 and a fuse 36. In addition, the circuit comprises an anchor lantern 11 , arranged to emit 360° white light during anchoring. This is also connected to the battery via a switch 16 and a fuse 35. All lanterns are thus con nected in parallel.

With reference to Figure 2, a description is given in the following of a preferred embodiment of the invention. The parts belonging to a standard navigation light in stallation described with reference to Figure 1 are shown here with the same refer ence numerals 10, 11, 12, 13, 14, 15, 16, 17, 18, 35, 36, 37 and are therefore not de scribed in more detail below.

Figure 2 shows a navigation light installation with an emergency signal system ac cording to the invention. In addition to the previously described lanterns 11, 12, 13, 14, 15, the switches 16, 17, 18 and the battery 10, the system comprises an emer gency signal unit, generally designated 20, in connection with the navigation lights. The emergency signal unit 20 comprises a switch 24 for switching on and off emer gency signals via the lanterns 11, 12, 13, 14, 15. The switch further has a built-in in dicator, here in the form of a LED lamp 25, which indicates with flashing lights when the system is in operation. The use of a LED lamp in this context has clear ad vantages as the indicator can be made small, is reliable during a long time, has a low cost and has extremely low power consumption.

Furthermore, the signal unit has a relay 26 which is switched off during normal operation of the navigation lights but is closed when the switch 24 is switched on and thereby switches on the lanterns 11, 12, 13, 14, 15 on. In the example, the relay 26 is connected between the positive pole of the battery 10 and the respective par allel-connected lanterns 11, 12, 13, 14, 15.

Diodes 21 , 22 and 23 are connected between the relay 26 and the respective lan terns 11, 12, 13, 14, 15 such that diode 21 is connected in parallel with switch 16, di ode 22 is connected in parallel with switch 17 and diode 23 is connected in parallel with switch 18. The diodes 21, 22, 23 have the task of ensuring that no more lan terns than desired are lit when each of the normal switches 16, 17, 18 is closed for operation of one or more lanterns.

Between the lanterns 11, 12, 13, 14, 15 and the negative pole of the battery 10 (and the ground of the ship) a second relay 28 is arranged, which is configured to vary the current in the circuit when the switch 24 closes the circuit and activates the safety system. This causes the lanterns 11, 12, 13, 14, 15 to flash and indicate that the ship is in distress at sea. It should also be noted that the relay 28 is closed in the passive position and does not load the navigation light circuit in normal operating modes, but only loads the circuit in the emergency signal state. The relay 28 is further connected to receive a control signal from a programmable control unit 30, also referred to as microcontroller, which has a plurality of connections. A voltage regulator 27 is also connected to the control unit 30 to ensure a voltage of 5 volts to the control unit 30. The voltage regulator 27 has three connections and is connected to the 5-volt connection of the control unit 30, to the negative terminal (ground) of the battery 10 and to the switch 24.

The control unit 30 is connected via a ground connection to the negative pole of the battery 10 and at a 5-volt connection to the voltage regulator 27. At the connec tion point of the control unit, marked "13", it is connected to a control side of the re lay 28. In this embodiment, the control unit 30 together with the relay 28 forms a control means according to the invention, and the control unit 30 is arranged to vary, together with the relay 28, the current through the lanterns 11, 12, 13, 14, 15 such that these are caused to pulsate or flash. In the described embodiment, the lanterns are caused to flash in accordance with the Morse code signal for SOS, i.e., three short light signals, three longer light signals, and three short light signals, which are then repeated.

The control means described in the illustrative example is formed by a program mable control unit, which together with a relay provides a variation of the current through the lanterns. It should be understood, however, that there are a number of other possibilities for those skilled in the art to provide a control means which can vary the current in the circuit of the lanterns and produce a pulsating or flashing ef fect thereof. Various simple relay solutions or mechanical solutions are available, for example. It should also be noted that the described embodiment enables, thanks to the relay 26 and the diodes 21 , 22, 23, activation of an emergency light function without the navigation lights being switched on separately. For simpler solutions, switching on the navigation lights may also be required to activate the emergency light functionality.

Figure 3 shows a wiring diagram for a separate emergency signal unit 20, which is intended to form the emergency signal system according to the invention together with a standard navigation light installation. Figure 4 schematically shows the physi cal design of an embodiment of the emergency signal unit 20. The same reference numerals as in Figures 1 and 2 are used for corresponding parts in Figures 3 and 4, the parts described above not being described in more detail in the following. The parts shown in Figures 3 and 4 are also apparent from the dashed circumference in dicated in Figure 2, generally denoted by the reference numeral 20.

The emergency signal unit 20 differs most closely from the solution shown in Fig ure 2 in that connection points for connection to different positions in a navigation light circuit are defined. Thus, the emergency signal unit has two connection points 41 and 42, respectively, for connection to a power source, such as a battery, wherein connection point 41 is intended to be connected to the positive pole of the power source and the connection point 42 is intended to be connected to the nega tive pole (ground) of the power source. Furthermore, the emergency signal unit has a connection point 46 for connection to one side (positive side) of an assembly of the port lantern 13, starboard lantern 14 and stern lantern 15, and a connection point 45 for connection to one side (positive side) of a motor lantern 12, and furthermore a connection point 44 for connection to one side (positive side) of an anchor lantern 11. In addition, the emergency signal unit has a connection point 43 for connection to the other side (ground side) of the said lanterns 11, 12, 13, 14, 15.

As can be seen in Figure 4, all connection points 41, 42, 43, 44, 45, 46 of the ex ample are arranged on a body associated with the emergency signal unit, here in the form of a housing 40. On the inside of the housing 40, the control unit 30, also shown in Figure 3, the voltage regulator 27, the two relays 26 and 28 and the diodes 21, 22, 23 are fixed (not shown in figure 4), as is shown by the dashed circumfer ence 40 in figure 3. It is to be understood that the number of connection points and different functions can be varied in adaptation to different navigation lighting solu tions and ships.

As is further shown in both Figure 3 and Figure 4, the actuator 24 and the indica tor lamp 25 are arranged in a separate unit, physically separated from the housing 40. In the shown solution, both the actuator 24 and the indicator lamp 25 are ar ranged in a common housing 29, which is connected to the housing 40 by means of a cable 32 containing the electrical connections between the unit 20 and the unit 29 in accordance with Figure 3. In the shown embodiment, the actuator is designed as a pushbutton 24 and the indicator 25 is arranged in the pushbutton 24. Flowever, it should be understood that various technical solutions are available for the realization of an actuator and an indicator according to the invention. According to the inven tion, it is also suitable to provide a preventing means (not shown) to ensure that the actuator cannot be activated by mistake. This can be realized, for example, by a transparent lid which is placed over the pushbutton 24 and which is arranged such that it must be lifted before the pushbutton is activated. It is to be understood, how ever, that a number of possibilities for the design of actuator, locking means and in dicator are at hand within the scope of the appended claims.

In a particular variant of the signal system and the signal unit according to the in vention, a control means connected to the navigation lights can also be used for alarm situations other than distress at sea by causing the signal unit to control the navigation lights to variation in response to an alarm signal from a detector belong ing to the ship. An applicable situation where this solution is advantageous is detec tion of a leak or burglary on ships that are unmanned in port. The surroundings can then be made aware that something is wrong.

The invention as defined by the claims has been explained above by means of a description of a preferred embodiment. It is to be understood, however, that the scope of the invention is not limited by the described embodiment but may be varied within the scope of the appended claims. It will thus be appreciated that the electri cal circuit to achieve a variation of the light intensity can be designed in a variety of ways and by means of different components. It should also be understood that the light variation achieved according to the invention is not limited to an SOS signal but that the necessary attention related to sea distress also can be achieved in other ways. The invention is also not limited to a 12 V battery, but other current sources and operating voltages suitable for each vessel type may just as well be considered. Furthermore, the solution of the invention can also be advantageously supplemented with a specific battery for emergency operation, in order to ensure that the emergency signal system is functional even if ordinary electrical power supply has been eliminated. Further advantageous embodiments may comprise additional emergency aids connected to and activated by means of the actuator. This can refer to additional lighting aids in addition to the navigation lights, sound signals or activa- tion of disposable aids such as emergency rockets or the like. Furthermore, the sys tem can be activated by means of another system on the ship.