EP1049058A2

EP1049058A2 - Protection system

Info

Publication number: EP1049058A2
Application number: EP00201420A
Authority: EP
Inventors: Lex Elzo Westera
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-04-26
Filing date: 2000-04-22
Publication date: 2000-11-02
Also published as: NL1011891C1; EP1049058A3

Abstract

Protection system for a caravan or car trailer. According to the invention an alarm unit is brought into a conditional state of alarm as soon as the current supply to the caravan or car trailer is disconnected. If next the current supply is restored, or if the caravan is moved, the alarm unit is brought into a state of alarm. The protection system is controlled with a remote control unit.

Description

The invention relates to a system for protecting a coupling between a car trailer, like a caravan, and a motor car or a car trailer parking place, which coupling includes an electric coupling between an electric installation of the car trailer and a current supply. More in particular the protection system is intended to prevent a car trailer from being disconnected and taken away unobserved, for example on a restaurant car park or a camping car park.
An apparatus for protecting a coupling between a motor car and a car trailer is known from application EP-A-0 446 498. Said application discloses a mechanical protection, which makes the mechanical coupling between a caravan and a motor car substantially inaccessible by covering it with a cap that can be locked. Unfortunately mechanical protection means have a limited effect, because potential thieves usually develop fast opening methods for the limited number of embodiments available.
The inventive system obviates this disadvantage. It is invisible and has a frightening and surprising effect which tends to discourage potential thieves up to the point that they give up their activities. For that purpose the invention is characterized in that the system is arranged to protect the electric coupling and is provided with an additional current supply and with an electric circuit, connected to the electric coupling.
A very favourable embodiment according to an aspect of the invention is characterized in that the electric circuit is provided with first detection means, for detecting a disconnection of the electric coupling and for bringing the electric circuit from a state of rest into a conditional state of alarm. This relieves the user of the obligation to switch on the system if he leaves the car trailer behind. The system in fact switches on at the very moment a first, possibly criminal action takes place.
An advantage that should not be underestimated here is that the system will make it much harder or even impossible to practice fraud to an insurance company. The argument of a robbed car trailer owner that he must have forgotten to switch on the alarm is no longer credible.
A favourable embodiment according to another aspect of the invention is characterized in that the electric circuit is provided with second detection means, for bringing the electric circuit from a conditional state of alarm into a state of alarm when a connection of the electric coupling to a current supply is detected or if a vibration or a movement of the car trailer is detected or if the car trailer is opened or if the presence of a person in the car trailer is detected. In a further favourable realization the electric circuit is provided with switch means, for switching on an audible and/or visual alarm and/or an electrically operated brake, acting upon a wheel of the car trailer when the electric system is in the state of alarm.
A favourable embodiment of the invention provides an opportunity to uncouple the car trailer in a simple manner without the electric system entering the state of alarm and to end a state of alarm immediately. The invention is thereto characterized in that the electric circuit is provided with third detection means, for receiving commands of a remote control. A favourable realization is characterized in that the third detection means are arranged for receiving a first reset-signal for bringing the electric circuit from the conditional state of alarm into the state of rest and a second reset-signal for bringing the electric circuit from the state of alarm into the conditional state of alarm.
In a further favourable embodiment, which offers the possibility to bring the system into the conditional state of alarm or to generate an alarm, the invention is characterized in that the third detection means are arranged for receiving a first set-signal for bringing the electric circuit from a state of rest into the conditional state of alarm and of a second set-signal for bringing the electric circuit in a state of alarm.
The system moreover comprises a remote control unit for transmitting electromagnetic radiation, for transmitting the first and second reset-signals and the first and second set-signals.
The system moreover comprises a push-button, for mounting onto the car trailer, or a vibration sensor or a PIR sensor or an ultrasonic sensor for bringing the electric circuit from a conditional state of alarm into a state of alarm.
The invention also relates to a protection circuit, suitable for application in a system as described above.
The invention will now be further explained with a reference to the following figures, in which:

Fig. 1: schematically shows a possible embodiment of the system;
Fig. 2: schematically shows a possible embodiment of the electric circuit.

Fig. 1 schematically shows a possible embodiment of the system, which can be mounted into a car trailer or caravan, not shown in the figure. In the system an electric circuit 1 is detachably connected via a connection 2 to a current supply. In this embodiment circuit 1 is connected to an ultrasonic detector 4 via a connection 3, and to a flashing light 6 and a siren 7 via a connection 5. Circuit 1 is moreover provided with an additional current supply, in this embodiment an accumulator 8, which, if connection 2 is intact, is charged from the current supply. Moreover circuit 1 is provided with a light sensitive diode 9, which may receive modulated light signals from a remote control unit 10.
If connection 2 is intact and the caravan is therefore coupled to a vehicle or to a fixed current supply, like this is the case while staying for example on a camping, circuit 1 is in a state of rest. If connection 2 is disconnected and apparently something happens, circuit 1 will switch within a few seconds to a conditional state of alarm. In the conditional state of alarm, output signals of ultrasonic detector 4 will switch circuit 1 immediately to a state of alarm, in which flashing light 6 and siren 7 are switched on.
Remote control unit 10 comprises an off button 11, a standby button 12 and an on button 13, with which circuit 1 may be switched into respectively the off state, the conditional state of alarm or the state of alarm. If one leaves for example on a camping the caravan for a little while, then the system can be brought in the conditional state of alarm with the remote control unit. If somebody enters the caravan, then the alarm will be switched on with the aid of ultrasonic detector 4 or a vibration detector or a PIR detector. If one wants to move the caravan himself, then the disconnection of connection 2 will bring circuit 1 in the conditional state of alarm, but with remote control unit 10 this can be cancelled. If things get out of hand or if one wants to attract attention from its environment, then the alarm may be switched on with on button 13 without delay.
Remote control unit 10 is as such well known in the art. It is provided with a circuit and a LED 13 such that when a button is pushed, LED 13 will be switched on and will radiate light provided with some modulation, in a manner well known in the art. By pushing standby button 11, circuit 1 will be switched from the state of alarm to the conditional state of alarm.
Fig. 2 schematically shows a possible, simple embodiment of electric circuit 1. In this embodiment an accumulator 8 is charged from the current supply of the motor car via connection 2 and a charge resistor 14. On the side of connection 2, a schmitt trigger 16 is coupled to resistor 14 via an RC circuit, such that on the output of schmitt trigger 16 a positive edge is produced about two seconds after connection 2 is disconnected. This positive edge triggers a flip-flop 17, such that an output Q becomes true. Output Q of flip-flop 17 enables a monostable multivibrator 18, which will be triggered if an alarm is detected, for example via an ultrasonic detector, which alarm reaches monostable multivibrator 18 via input 3 and a schmitt trigger 19. This causes an output Q of monostable multivibrator 18 to become true for example during one minute, therewith switching on flashing light 6 en siren 7 via an amplifier 20 and output 5. The duration is determined by an RC network, connected to monostable multivibrator 18.
In order to reset electric circuit 1, a receiver circuit 20 is provided, as such well known in the art, to a which light sensitive diode 9 is connected. When a modulated signal is received caused by pushing of off button 11, both flip-flop 17 and monostable multivibrator 18 are reset via reset inputs R. When a modulated signal is received caused by pushing standby button 12, flip-flop 17 is set via its set input S, therewith bringing the circuit in the conditional state of alarm. When a modulated signal is received caused by pushing on button 13, monostable multivibrator 18 is set via its set input S, therewith causing an alarm. Remote control unit 10 and receiver circuit 20 are commercial available as a set. It is also possible of course to use a remote control unit 10 based on RF radiation instead of IR radiation. Sets of that type are also commercial available.
In situations in which the car trailer remains uncoupled to a current supply for a prolonged time, it is advantageous to add a solar cell 21 to the system, such that accumulator 8 will be charged and the alarm will remain useful. It is necessary then to bring the system in the conditional state of alarm with remote control unit 10.

Claims

System for protecting a coupling between a car trailer, like a caravan, and a motor car or a car trailer parking place, which coupling includes an electric coupling between an electric installation of the car trailer and a current supply, characterized in that the system is arranged to protect the electric coupling and is provided with an additional current supply and with an electric circuit, connected to the electric coupling.
System according to claim 1, characterized in that the electric circuit is provided with first detection means, for detecting a disconnection of the electric coupling and for bringing the electric circuit from a state of rest into a conditional state of alarm.
System according to claim 2, characterized in that the electric circuit is provided with second detection means, for bringing the electric circuit from a conditional state of alarm into a state of alarm when a connection of the electric coupling to a current supply is detected or if a vibration or a movement of the car trailer is detected or if the car trailer is opened or if the presence of a person in the car trailer is detected.
System according to claim 3, characterized in that the electric circuit is provided with switch means, for switching on an audible and/or visual alarm and/or an electrically operated brake, acting upon a wheel of the car trailer when the electric system is in the state of alarm.
System according to claim 3, characterized in that the electric circuit is provided with third detection means, for receiving commands from a remote control.
System according to claim 5, characterized in that the third detection means are arranged for receiving a first reset-signal for bringing the electric circuit from the conditional state of alarm into the state of rest and a second reset-signal for bringing the electric circuit from the state of alarm into the conditional state of alarm.
System according to claim 5, characterized in that the third detection means are arranged for receiving a first set-signal for bringing the electric circuit from a state of rest into the conditional state of alarm and of a second set-signal for bringing the electric circuit in a state of alarm.
System according to claim 5, characterized in that the system also comprises a remote control unit for transmitting the commands.
System according to claim 5, characterized in that the system also comprises a push-button, for mounting onto the car trailer, or a vibration sensor or a PIR sensor or an ultrasonic sensor for bringing the electric circuit from a conditional state of alarm into a state of alarm.
Protection circuit, suitable for application in a system according to one of the previous claims.