This invention relates to weighing apparatus and more particularly, though not exclusively, it relates to weighing apparatus for weighing vehicles, for example trucks or lorries.

Weighing apparatus for weighing vehicles such as trucks or lorries ir= often referred to as a weighbridge. Known weighbridges comprise a metal plate which is set into the ground. A truck or lorry drives its front wheels onto the weighbridge and obtains a weight in respect of the front wheels, the so called front axle weight. It then drives its rear wheels onto the weighbridge and obtains a weight for the rear wheels - the rear axle weight. The total mass of the lorry may then be calculated. The mass of the load may also be calculated.

A problem in the past has been that weighbridges have tended to accumulate dirt especially in the form of gravel or sand. This has sometimes jammed the weighbridge or rendered it not able to weigh accurately or consistently. Gravel and sand has ingressed into a gap defined by a relatively stationary surface and a plate which supports the vehicle's wheels. Gravel and sand causes friction and can lead to damage to the

weighbridge.

The present invention has been made from a consideration of this problem.

According to a first aspect of the present invention there is provided a weighing apparatus for weighing the axle weight of a vehicle comprising an entry ramp over which the vehicle can be driven to cause the wheels of the vehicle to be raised from the ground, the ramp leading to a support on which a weighbridge is located at a raised level from the ground and an exit ramp from the support to the ground.

By raising the weighbridge from the ground dirt is much less likely to accumulate in the weighbridge.

The support on which the weighbridge is located is preferably provided on a platform.

According to a second aspect of the present invention there is provided a weighing apparatus for weighing the axle weight of a vehicle having washing means arranged in use to wash a vehicle's wheels prior to the wheels being positioned on a weighbridge.

Preferably the washing means comprises a water

bath. The washing means is preferably arranged adjacent the weighbridge such that the vehicle wheels must pass through it prior to being driven onto the weighbridge. A vehicle support such as a gantry of support frame may provide a path for a vehicle's wheels from the water bath to the weighbridge at a raised level from the ground. This may be in the form of a raised platform or raised framework. The purpose of this is to prevent a vehicle's wheels from accumulating further dirt and gravel subsequent to it having been washed in the water bath and prior to positioning on the weighbridge.

The vehicle axle weights are measured dynamically, i.e. while the vehicle is moving.

Recording means may also be provided for remote monitoring a vehicle's axle weight and/or for providing a hard copy of a vehicle's weight axle and/or identification. The recording means preferably comprises an electronic control which may be arranged to monitor the relevant time and/or date of weighing and to provide information in respect of the total amount of vehicle axle weight passing over the weighbridge during any predetermined period.

This feature is considered to be particularly useful in helping to minimise fraud on worksites or

excavation sites. Fraud has occurred in the past where a lorry driver has been paid in relation to the weight of his load being carried. It has been possible to, for example, bribe a guard placed on an exit to an excavation site or to fraudulently record a higher number of visits than has actually taken plate. Because the present device is arranged to record the exact exit weight of a lorry it can be used to provide an unbiased automatic record of the total load of a lorry leaving a site. Similarly the total of all lorries' loads can be computed by adding individual masses removed from a site during any period. Thus for example a site operator can monitor the efficiency of a contractor.

An embodiment of the present invention will now be described, by way of example only, with reference to the figures in which:

Fig. 1 shows a plan view of a weighing apparatus in accordance with the invention;

Fig.2 shows a partial overall view of the arrangement in Figure 1 ;

Fig. 3 shows a detailed view of the arrangement of Fig. 2; and

, Fig. 4 shows an overall view of an alternative embodiment having a spray assembly.

Referring to Figures 1 to 3 a vehicle cleaning and weighing apparatus 10 has a pair of ramps 11 and 12 and a water bath 13 arranged such that a vehicle (not shown) is able to drive up the ramps 11 and 12. The ramps 11 and 12 comprise a series of angle irons which are arranged to break up any mud caked onto the vehicle's tyres. A water bath 13 is arranged to wash off the mud and dirt on the tyres. Raised gantry sections 14 and 15 enable a vehicle to pass from the water bath 12, above the level of the ground so that no further dirt can be accumulated on its tyres. The gantry sections 14 and 15 also permit water to be drained from the tyres. A vehicle's front tyres may then be driven onto a weighbridge 16 which is raised from the ground. The front axle weight can then be calculated. The vehicle is then driven so that its front tyres pass over a second set of raised gantry sections 17 and 18 and onto another pair of ramps 19 and 20. The rear tyres are then positioned on the weighbridge 16 and the rear axle weight is then calculated. The total weight of the vehicle may then be calculated. Because the weight of the empty vehicle is known it is thus possible to calculate the weight of the total load. These details including the time, date and vehicle driver

identification are printed on paper and appear at the printout station 21. A separate copy may be printed in a remote office.

Figure 4 shows a similar arrangement, in which like parts bear the same reference numerals as in figures 1 to 3. A frame 24 is provided through which water may pass and in which nozzles (not shown) are formed. This spray arrangement 24 provides overall cleaning of a vehicle prior to it passing onto the weighbridge 16. In this respect attention is drawn to the applicants' copending UK Patent application No. 9014183.9 (publication No. GB 2 239 848A) which teaches the construction of a similar vehicle cleaning apparatus.

The embodiments described with reference to figures 1 to 4 inclusive show a transportable temporary vehicle wheel cleaning and weighing arrangement. The complete arrangement which comprises sections of raised platform, ramp sections and the water bath, may be transported and erected within a relatively short period. The weighbridge is recessed into a raised weighbridge support platform 16A.

It will be appreciated that variation to the aforementioned embodiments may be made without departing

ϊrom the scope of the invention.