GB2328307A - Vehicle trailer monitoring system - Google Patents

Abstract

A monitoring system for the trailer of a tractor/trailer unit, comprising a secure housing (22, Figs 2 and 3) on the trailer unit, accessible by key, keyboard or the like only to an authorized person, the housing accommodating a function control key panel 100, a microprocessor 102, micro-electronics, a battery 108 rechargeable from the tractor unit, sensors 110 for detecting unauthorized trailer movement and/or access to the load space, and alarm means 112 operable if the sensor means produces abnormal signals. The sensors include ones associated with the front-end land legs 106 of the trailer with the load space of the trailer and with the wheels of the trailer.

Description

Vehicle Monitoring System This invention relates generally to vehicle monitoring systems and in particular to a monitoring system for the trailer of a tractor/trailer unit.

In its broadest aspect, the present invention provides a monitoring system for the trailer of a tractor/trailer unit, comprising a secure housing on board the trailer unit and accommodating at least a function control key panel, a microprocessor, micro-electronics and a battery power supply, sensors associated with the frontend land leg of the trailer, with the enclosing structure of the cargo space of the trailer and with the wheels, said sensors being connected to the microelectronics, and an alarm means operable by the microprocessor when the monitoring system is activated responsively to abnormal signals received by the micro-electronics from any one or more of the sensors.

The battery is preferably rechargeable from the tractor when the latter is hitched to the trailer.

Thus, the primary object achieved by the present invention is that of reducing risk of illegal tampering with the trailer, especially but not only when the trailer is parked with the tractor disconnected, either by an attempt at unauthorised entry into the cargo space or an attempt at theft of the complete trailer.

In the former case, any attempt at entry into the cargo space through doors, roof or wall panels, or curtains in the case of a curtain-sided trailer, is detected, as by means of photo-electric sensors, internal space sensors or the like, whereupon the alarm means, e.g. flashing lights and/or siren, control centre communication means, etc., is operated. In the latter case, sensors detect operation or attempted operation of the land legs and thereby detect an attempt at unauthorised movement of the trailer and cause operation of the alarm system.

Preferably, a vehicle tracking unit is also incorporated in the secure housing and is brought into operation at least if abnormal signals are produced by the wheel sensors. The vehicle tracking system may also be designed to be brought into operation upon any violation of the trailer, as by remote signalling, or from a control centre.

With reference to use of the term "abnormal signals", it should be understood that in all instances normal signals may be zero, so that in practice the only signals produced by the sensors, or at least some of said sensors, are abnormal signals.

The monitoring system is preferably activatable and de-activatable at the secure housing by use of a key or key card or keyboard, and this secure housing is preferably also alarmed so as to cause the alarm system to be operated if any attempt is made to tamper with it. Only authorised persons, such as the driver, may possess the correct key or key card, or the correct code for the keyboard, for activating and de-activating the alarm system. However, the system may also instead or additionally be activatable remotely, as by radio or infra-red signalling. In this case, the driver need not know the access codes.

Most preferably, the alarm means is accommodated in the same secure housing as the microprocessor, micro-electronics and battery. However, it may sometimes be the case that elevated siting of the alarms, e.g. visual alarms, radio alarms, etc., is desirable to maximise range, in which instance the alarms may be contained within a second secure housing.

Enclosure of the alarms may require that the enclosure (or second enclosure) must have a window for transmissions of sound, light and radio signals. This window could be constituted by a lockable housing door.

The trailer cabling is preferably routed through the secure housing, not only to provide for recharging of the internal battery, but also to activate alarms such as flashing lights. Cable entry via sealed glands is preferred to the use of connectors for added security.

The secure housing itself, at least when locked, is desirably sealed against water and dust, in order to protect a key panel, microprocessor and micro-electronics, and is preferably sufficiently rugged to resist blows from a hammer or the like.

Preferably, the land leg of the trailer is raisable and lowerable by a motor/gearbox unit powered by the internal battery. If the secure housing is located adjacent the trailer ground stand, the motor/gear box unit may also be securely accommodated in this housing. A switch in circuit with a relay may determine the direction of movement of the land leg, and also provide an override position. However, the relay is preferably only energised to start the motor/gearbox unit when an access code is confirmed at the key panel and no alarm signals are present. The advantage of driving the land leg from a motor/gearbox unit within the secure housing (as compared to using power from the tractor unit for example) is that the land leg cannot be operated illegally unless the secure housing is broken open. However, the ability to drive the land leg from the internal motor may require careful control of full load surge current, break current, etc. within the control electronics, especially to prevent demagnetisation of the motor if a permanent magnet motor is employed.

The housing itself may be protected in the same way as the cargo space, and the system may also be designed to detect attempted "hot wiring" by interference with cabling or cable connections. Exposed cables are preferably armoured.

A particular advantage of the monitorig system of the invention is that it can have incorporated into it sensors for monitoring normal operation of the tractor/trailer unit. Thus, tyre pressure sensors may be included in the system, as well as a tractor/trailer hitch pin sensor, for example. The latter sensor may also serve to detect unauthorised disconnection of the trailer from the tractor, possibly additionally to detection of illegal decoupling by means of weight/stress sensors on the land leg.

The invention is further described with reference to the accompanying drawings, in which: Figure 1 is a schematic diagram of the system; Figure 2 shows an alarmed trailer diagrammatically, Figure 3 is a block circuit diagram; Figure 4 shows an exernplary secure housing; and Figure 5 shows a switching circuit for the ground stand control.

Referring to the drawings, the basic system is shown in Figure 1. It comprises a key panel 100 interfaced with a microcontroller 102 interfaced firstly with a land leg driving motor/gear box unit 104 for controlling up and down movement of the land leg 106, secondly with a power supply unit 108, thirdly with various sensors 110 and fourthly with alarms 112, e.g. a zenon flasher unit 114, a siren 116, and a radio transmitter 118. The alarm is also interfaced with the vehicle lights cable 120 and the trailer lights 122. The power supply unit is supplied from an internal battery 124 and is also interfaced with the tractor power supply 126, more especially to enable re-charging of the internal battery.

Figure 2 shows a trailer 10 appertaining to a tractor/trailer unit, having a front end land leg 12 which could be operable through a gear box 12A under the control of a driver held hand winch, but alternatively is controlled by a motor, as later described.

The trailer also has a front end hitch pin 14, rear wheels 16 and rear lighting 18.

At the front end, a cable and suzle connector 20 is also provided for transmitting power from the tractor to the trailer lighting, air brakes etc.

Towards the front end of the trailer, an externally accessible housing 22 is securely fixed to the chassis structure of the trailer. This housing 22 (see Figure 3) accommodates a microprocessor 24, micro-electronics 26, a vehicle tracking unit 28 and a battery 30 for power supply. The battery 30 is rechargeable from the tractor in normal use of the tractor/trailer unit. The housing 22 may also incorporate the land leg gear box, but alternatively may be entirely separate therefrom.

Sensors of various suitable types are provided at different points on the trailer, including a sensor 32 for detecting operation of the land leg gear box, a cargo space violation sensor 34 and a wheel rotation sensor 36.

These sensors 32, 34, 36 are connected to the micro-electronics 26, which interprets and processes the signals and produces related signals in digital form for input to the microprocessor 24.

On receipt of abnormal signals from any one or more of the sensors when the monitoring system is activated, i.e. signals indicative of operation of the ground support stand, of cargo space violation or of wheels rotation, the microprocessor generates control signals for an alarm means 38, whereby, for example, the trailer lights are caused to flash and a concealed siren is caused to sound. In addition, at least if the wheels rotation sensor produces an abnormal signal, the vehicle tracking unit, operating for example by VHF radio or by GPS, is brought into operation.

In this way, any attempt at theft from the trailer is made instantly conspicuous, whether the trailer is parked disconnected from the tractor or in transit still connected to the tractor. Moreover, in the event of an attempt at theft of the complete trailer unit, not only is the vehicle made conspicuous but additionally the appropriate authorities are alerted and are able to track the stolen trailer.

It is also possible to include a hitch-pin sensor, not only to detect unauthorised disconnection of the trailer from the tractor but also to monitor normal operation of the hitch. Other normal features, such as tyre pressures and door locks may be monitored by suitable sensors, the door lock sensor also serving to detect unauthorised door opening.

Figure 4 shows a metal or plastics secure housing 22 having a transparent, lockable hinged door 23 behind which can be seen a key panel 40, siren 42, strobe light 44 and antenna 46. The strobe light and siren are able to provide sensing and detection against unauthorised opening of the door. The housing 22 also accommodates a battery 48, motor/gear box unit 50 and interface 52 for incoming cables connecting to sensors, alarms, etc. The housing, when closed, is sealed against water and road dust. Trailer cabling is routed through the box to allow recharging of the battery from the tractor.

Figure 5 is a circuit diagram of a motor control unit for the trailer ground stand.

Motor 54 connects via a manually operable three-way switch 56 to a relay 58 and internal battery 60. Switch 56 enables up and down movement of the ground stand, with a centre position for emergency over-ride. The relay is switched by the microcontroller only on pressing a start button following confirmation of an access code and the absence of abnormal sensor signals.

Reference has been made to a radio transmitter 118. In fact, the system may provide for two-way communication with a command centre, enabling all trailer violations to be reported to a controller, a tracking system to be brought into operation from the command centre and various functions of the alarm system to be initiated or performed remotely, such as affording access to the secure housing, operation of the land leg gear, etc.

Additionally, the alarm system may be interfaced with the electronic unit controlling the trailer anti-skid braking system, whereby on detection of an attempted trailer theft when the trailer is parked, the brakes are locked on as soon as the appropriate service line is connected, preventing the trailer from being moved. Preferably, this brake lock will be capable of being overridden from the command centre, so as to allow covert surveillance and remote immobilization when appropriate.

Claims (16)

claims

1. A monitoring system for the trailer of a tractorltrailer unit, comprising a secure housing on board the trailer unit and accommodating at least a function control key panel, a microprocessor, micro-electronics and a battery power supply, sensors associated with the front-end land leg of the trailer, with the enclosing structure of the cargo space of the trailer and with the wheels, said sensors being connected to the micro-electronics, and an alarm means operable by the microprocessor when the monitoring system is activated responsively to abnormal signals received by the micro-electronics from any one or more of the sensors.

2. A monitoring system according to claim 1, wherein the battery is rechargeable from the tractor when the latter is hitched to the trailer.

3. A monitoring system according to claim 1 or claim 2, wherein the alarm means is operated by any attempt at entry into the cargo space through the doors, roof or walls (including any curtain walls).

4. A monitoring system according to any of claims 1 to 3, including movement sensors associated with the land leg of the trailer.

5. A monitoring system according to claim 4, wherein the movement sensors cause the alarm means to operate unless the movement of the land leg is authorised by entry of a correct access code at the control key panel.

6. A monitoring system according to any of claims 1 to 5, including movement sensors associated with the wheels and producing abnormal signals in the event of unauthorised movement of the trailer.

7. A monitoring system according to claim 6, including a vehicle tracking system incorporated in the secure housing and brought into operation if abnormal signals are produced.

8. A monitoring system according to any of claims 1 to 7, wherein the monitoring system is activatable and de-activatable at the secure housing by use of the control key panel.

9. A monitoring system according to any of claims 1 to 8, wherein the secure housing is itself alarmed against unauthorised access.

10. A monitoring system according to any of claims 1 to 9, wherein the alarm means is also incorporated in the secure housing.

11. A monitoring system according to any of claims 1 to 9, including a second secure housing accommodating the alarm means.

12. A monitoring system according to any of claims 1 to 11, in which the secure housing accommodating the alarm means has a transparent window for signals transmission to the exterior.

13. A monitoring system according to any of claims 1 to 12, wherein the secure housing is located adjacent the land leg and a motor/geabbox unit for driving the ground stand is also accommodated in the housing.

14. A monitoring system according to any of claims 1 to 13, also including tyre pressure and/or tractor/trailer hitch pin sensors.

15. A monitoring system according to any of claims 1 to 14. having means of communication with a remote command centre, whereby at least some functions of the alarm system can be initiated or performed remotely.

16. A monitoring system substantially as hereinbefore described with reference to the accompanying drawings.