Lorries having bodies for receiving goods are well known. Such lorries usually have a body which comprises lighting for lighting the interior of the body in order to facilitate loading and unloading of the goods. The lighting is required because the lorries are invariably loaded and unloaded during hours of darkness, for example at night or very early in the morning.

The lighting in the lorries causes considerable problems. If the lighting is bulb lighting, then the bulbs tend to extend proud of mounting surfaces in the body, and thus the bulbs are easily struck and destroyed by the goods as they are loaded and unloaded. In order to overcome these problems, it is known to provide the lorries with bulkhead light fittings. These bulkhead light fittings protect the bulbs. However, the bulkhead light fittings still extend proud of the mounting surfaces and so that they are still subject to getting struck and destroyed by the goods as the goods are loaded and unloaded.

It is known to try and overcome the problems of bulbs and bulkhead light fittings by having lighting mounted in or behind a false ceiling. However, the false ceiling occupies valuable space in the body, and this occupied space would be better employed for receiving the goods.

Furthermore, the false ceiling tends to cause condensation which is often undesirable, for example in refrigerated bodies for receiving food.

The above problems have existed for many years and it is an aim of the present invention to reduce these problems.

Accordingly, in one non-limiting embodiment of the present invention there is provided a lorry having a body for receiving goods, the body comprising lighting for lighting the interior of the body in order to facilitate loading and unloading of the goods, characterised in that the lighting is electroluminescent lighting.

The electroluminescent lighting is advantageous in that it is able to be constructed in a substantially flat form. Thus there is no need to have the lighting protruding into the interior of the body where it is available for being struck and destroyed during loading and unloading of the goods.

The electroluminescent lighting may be surface mounted inside the body. Because the electroluminescent lighting is able to be produced to be very flat, the surface mounting of the electroluminescent light will still not cause the electroluminescent light to protrude substantially into the interior of the body.

The electroluminescent lighting may be in the form of at least one panel and/or at least one strip. The lorry may thus be one in which the panel is positioned on a ceiling of the body, and in which the strip is positioned on at least one wall of the body. Generally, the electroluminescent lighting may comprise just one or more panels, or just one or more strips, or a mixture of panels and strips. Whatever form the electroluminescent lighting takes, it may be positioned just on the ceiling, or just on the walls, or on both the ceiling and the walls.

Where the electroluminescent lighting is in the form of the strip, then the strip may be positioned on two of the walls, the walls being opposing longitudinally extending side walls. If desired, the strip may also be positioned on a wall which is a transversely extending wall adjacent a driver's cab part of the lorry.

Advantageously, the strip is positioned at a safe working height in order to minimise mishaps caused by persons incorrectly loading and unloading the goods. The safe working height may be the maximum height to which forks of a forklift truck should be raised. Alternatively, the safe working height may be the maximum height to which the products should be stacked.

The lorry may be one in which the body is a refrigerated body, and in which the goods are perishable goods.

With refrigerated bodies and perishable goods, another problem with the lighting in the known lorries is that of heat generation. More specifically, the refrigerated bodies are usually required to be at a temperature of minus 30-50°F. The above mentioned known bulb lighting generates localised hot spots which are undesirable, and which may cause premature perishing of perishable goods adjacent the hot spots. Bulkhead light fittings give out less localised heat but they still tend to give out some localised heat. With the electroluminescent lighting used in the present invention, the electroluminescent lighting is advantageous in that it emits a cold light. Thus the interior of the body can be illuminated without heat being generated from the lighting. This avoids the above mentioned localised hot spots.

Preferably, when the body is a refrigerated body, the electroluminescent light is powered by the battery of the refrigeration unit of the lorry. Currently, the known lighting for refrigerated bodies is powered by the battery of the lorry engine. The electroluminescent lighting used in the lorry of the present invention may also be powered from the lorry engine battery if desired, but advantages such for example as shorter lengths of wiring and ease of wiring may be obtained if the electrical power for the electroluminescent lighting is obtained from the battery used for the refrigeration unit battery.

Problems are sometimes encountered with the wiring in known wiring arrangements because the bodies of the refrigerated lorries are insulated. Wiring channels have hitherto often need to be cut into the insulation of the bodies. This is undesirable firstly insofar as it provides extra work in manufacture of the lorry bodies and secondly because it interferes with the insulating properties of the bodies. The wiring employed for the electroluminescent lighting used in the lorry of the present invention can generally be very thin and there is no need to custom form wiring channels unless this should be required. Surface mounting may be used if desired.

The electroluminescent lighting may be made of electroluminescent material which comprises a dielectric layer with a light-emitting phosphor layer sandwiched between two conductive surfaces. The primary purpose of the dielectric layer is to allow the electroluminescent material to withstand voltages without shorting between the conductive surfaces. The electroluminescent material illuminates when powered with alternating current.

Generally, the body may contain any of the goods currently transported in lorries. Where the body is a refrigerated body, then the refrigerated body may contain a wide variety of perishable goods such for example as meat, vegetables, beverages and ice cream.

The body of the lorry may be of any suitable and appropriate size and shape. Thus, for example, the body may have at least one open side which is closed by at least one curtain. Preferably, such a body has two open sides which are closed by curtains. The body may alternatively be, for example, the body of the lorry that is used on fire tenders and other lorries for attending fires where the body for receiving goods is one or more large containers which receive goods in the form of tools, equipment and accessories, for example for fighting fires. In the case of lorries such for example as fire tenders for fighting fires, the tools, equipment and accessories are often hurriedly thrown into the container or containers and existing conventional lights and their protective housings in the containers get broken. Often fire hoses with residual water get placed in the containers which can then cause electrical short circuits if the water gets on the broken lights. The use of the electroluminescent lighting helps to avoid this because it is much more difficult to damage the electroluminescent lighting.

Embodiments of the invention will now be described solely by way of example and with reference to the accompanying drawings in which: Figure 1 shows part of the interior of a known refrigerated body of a lorry; Figure 2 is a view looking into the interior of a refrigerated body of a first lorry of the present invention; Figure 3 is an amplified view of part of the lorry body shown in Figure 2; Figure 4 is an amplified view of another part of the lorry body shown in Figure 2; Figure 5 shows an electrical circuit for the refrigerated body shown in Figure 2; Figure 6 is a perspective view of a second lorry of the present invention; Figure 7 is a view from the rear of part of the inside of the body of the lorry shown in Figure 6; and Figure 8 is an exploded view of a waterproof electroluminescent lighting assembly.

Referring to Figure 1, there is shown a known refrigerated body 2 of a lorry. The body 2 is for receiving perishable goods. The body 2 has a side wall 4 and a ceiling 6. The side wall 4 and the ceiling 6 are shown with insulation 8. The ceiling 6 is provided with lighting in the form of a bulkhead light fitting 10. The bulkhead light fitting 10 extends from the ceiling 6 into the interior of the body 2. The bulkhead light fitting 10 will give out a certain amount of localised heat. This is undesirable because such localised heat may not be detected by a thermostat monitoring the overall temperature within the body 2, but such localised heat may be sufficient to cause premature perishing of closely adjacent goods. The bulkhead light fitting 10 is also likely to get struck and destroyed because it extends proud of the ceiling 6.

Still further, in order to mount the bulkhead light fitting 10, part of the insulation has to be cut away at area 12.

This causes undesirable work, and it also causes loss of insulation in the area 12. An electrical cable 14 for the bulkhead light 10 is also located in the insulation 8, causing more work and more loss of insulation.

The bulkhead light fitting 10 will usually employ a festoon bulb. In addition to giving off heat as mentioned above, the festoon bulb will usually be sensitive to vibration and it will thus have a poor life expectancy.

Furthermore, the festoon bulb will usually give out a poor light quality from a 12 volt or 24 volt battery supply.

Persons wishing to check a goods'manifest or labels on goods in the body 2 will thus have difficulty in seeing well enough to read the goods'manifest or the labels.

Referring now to Figures 2,3 and 4, there is shown the rear part of a lorry 16 of the present invention. The lorry 16 has a refrigerated body 18. Rear lorry wheels 20 are shown in Figure 2. The body 18 is for receiving perishable goods. The body 18 comprises a floor 22, walls 24, a ceiling 26, and a pair of doors 28 for enabling loading and unloading of the goods.

The body 18 has lighting 30 for lighting the interior of the body 18 in order to facilitate the loading and unloading of the goods. This lighting 30 is electroluminescent lighting 30. As can be seen from Figure 2, the electroluminescent lighting 30 is surface mounted and it is substantially flush with the interior of the body 18.

The electroluminescent lighting 30 includes four electroluminescent panels 32 which are mounted on the ceiling 26 as shown. The electroluminescent lighting 32 also includes a strip 34 which extends as shown along the two longitudinally extending side walls 24 of the body 18 and across the wall 24 which extends transversely adjacent a driver's cab part (not shown) of the lorry 16. The strip 34 is positioned at a safe working height which is the maximum height to which the products should be stacked.

The position of the strip 34 at this height not only helps to avoid over stacking but it also gives dimension to a person loading goods in the interior of the body 18.

Wiring 36 for the panels 32 and the strip 34 may be connected via an inverter circuit 38 to a 12 volt or 24 volt battery (not shown) which will already be provided in a refrigeration unit 40 in the interior of the body 18.

The inverter circuit 38 may be attached to the inside or the outside of the front wall 24.

Figure 3 shows how the wiring 36 may be arranged to run in a groove 42 in an extrusion 44. The extrusion 44 may be made from aluminium or any other suitable and appropriate material. The extrusion 44 acts as a cornice since it is positioned at the junction of the top of the walls 24 and the ceiling 26. The wiring 36 is in the form of flat cables so that the groove 42 can be very thin.

Figure 3 also illustrates how the panel 32 is a flat panel which is thus substantially flush with the inner surface of the ceiling 26, and which does not extend proud from the inner surface of the ceiling 6 in the same manner as the bulkhead light 10 shown in Figure 1.

Figure 3 also illustrates how the panel 32 is easily surface mounted to the inside surface of the ceiling 26 using a flat frame 46. The frame 46 can be made of rubber or any other suitable and appropriate material. The frame 46 is substantially flush with the ceiling 26. If desired, instead of using the frame 46, adhesives or appropriate other fixing means can be employed. Generally, whatever fixing means is employed, there is no need to cut into the insulation 48 of the ceiling 26, this being in direct contrast to the need to cut into the insulation 8 of the ceiling 6 for the bulkhead light 10 as shown in Figure 1.

As shown in Figure 2, rubber insulation/damp proofing 50 may be employed if desired. The provision of the extrusion 44 avoids the need to interfere with the insulation 48 of the wall 24.

Referring now to Figure 4, there is shown in more detail the strip 34. The strip 34 comprises an electroluminescent strip member 52 which is encapsulated in a support material 54 in the form of extruded clear polyvinyl chloride. The support material 54 has a flat base 56 provided with double sided adhesive tape or other suitable and appropriate adhesive. The base 56 is thus stuck to the inner surface 58 of the wall 24. There is no need to cut into the insulation 48 of the wall 24.

Referring now to Figure 5, there is shown in detail a preferred construction for the inverter circuit 38. As can be seen from Figure 5, the inverter circuit 38 comprises capacitor 60 and a regulator 62. The capacitor 60 and the regulator 62 form a 12 volt regulating section of the inverter circuit 38. This regulating section feeds to a timer oscillator chip 64 known as a 555 timer oscillator chip. Connected to the timer oscillator chip 64 as shown are capacitors 66,68 and resistors 70,72. The timer oscillator chip 64, the capacitors 66,68 and the resistors 70,72 form an oscillator part of the inverter circuit 38.

The timer oscillator chip 64 produces square wave of approximately 5KHz. This is feed to two transistors 74,76 which act as a current amplifier. The transistors 74,76 are connected as shown and they form a driver part of the inverter circuit 38. The transistors 74,76 drive a MOSFET 78. A high current sink and source capability ensures a fast switching of the MOSFET by overcoming the gate capacitance. The MOSFET 78 is connected to a primary winding 80 of a transformer 82. A capacitor 84 and an electroluminescent lamp 88 are provided as shown. The device 78, the transformer 82, the capacitor 84 and the electroluminescent lamp 88 form a power stage of the inverter circuit 38. The electroluminescent 88 forms a capacitive load. When the transformer 82 operating frequency duty cycle and the highly capacitive load from the electroluminescent lamp 88 are matched, then the result is a pure sine wave free of any spikes. The regulator 72 is known as a 7812 regulator and it is present in a 24/30 volt section of the inverter circuit 38 to protect the timer oscillator chip 64 and the MOSFET 78 gate from over voltage in some applications. An optional choke (not shown) may be provided to ensure the purity of the waveform. Output from the power stage is via a pair of smoothing capacitors 90,92.

Referring to Figures 6 and 7, there is shown a lorry 94 comprising a body 96, a driving cab 98 and wheels 100.

The body 96 has a floor 101, a roof 104 and curtain sides 106 as shown. As best seen in Figure 7, the inside of the roof 104 is provided with waterproof electroluminescent light assembly panels 108.

Figure 8 shows an exploded view of one of the panels 108. As can be seen from Figure 8, the panel 108 comprises a frame 110, a clear protective screen 112, an electroluminescent connector 114, an electroluminescent panel 116, and a back panel 118.

It is to be appreciated that the embodiments of the invention described above with reference to the accompanying drawings have been given by way of example only and that modifications may be effected. Thus, for example, the shape of the panel 62 may be varied. The position of the strip 34 may be varied. If desired, the electroluminescent lighting 30 could comprise all panels, or all strips, or a different mixture to that shown in Figure 2. Another type of circuit to that shown in Figure 5 may be employed. In Figures 6 and 7, the roof 104 can be provided with more or less than the illustrated four panels 108. Also, if desired, the construction of the panels 108 can be different from that shown in Figure 8.

The lorry may be one having a non-refrigerated body, in which case the body can contain any suitable and appropriate non-perishable goods, for example machine parts or furniture. If the lorry of the invention is one having a roof opening, for example a sliding roof opening, for loading and unloading goods then the electroluminescent lighting is advantageously positioned around the opening.

This makes the opening easier to see, especially in the dark.