GB2360170A - A tyre tag reader - Google Patents

Abstract

For companies that lease truck tyres, tyre management is important and the invention relates to a device for reading a tag mounted in or on a tyre 12 of a vehicle. The device has a reading head 2 connected to a handle 6 by an elongate shaft 4. The reading head 2 is mounted at right angles to the long axis of the shaft 4 which enables it to be positioned between a pair of adjacent truck tyres 12. The reading head 2 emits an electromagnetic field and receive signals emitted from a tyre tag in response. Information related to the tyre 12, for example identification, position, pressure, tread depth, etc. can be stored in and read from the tag. Means to measure tyre parameters such as tread depth and pressure may also be provided (figs 9-11). The reader enables data to be downloaded and uploaded between the tag and a computer, preferably wirelessly. The shaft 4 may be constructed with deviations 8 or arched regions to enable positioning around mudguards 10 and is long enough to span the double tyres 12 of a truck.

Description

2360170 TYRE MANAGEMENT The present invention relates to a system f or

tyre management, and to a device f or use with the system.

Leasing of truck tyres instead of buying tyres outright is increasingly popular with hauliers. In order for tyre leasing companies to optimise their profit from this activity, it is important to be able to measure f actors such as tyre wear, inflation pressure, and other factors affecting tyre life. Such measurements need to be taken for individual tyres and throughout a tyre 1 s lif e.

Tyre manufacturers use imprints on tyres to give them identification numbers or codes, orsometimes batch numbers. The numbers represent the manufacturer's name or number, the tyre size and type and the individual tyre ID number. The numbers are normally located on the side wall of the tyre, and are vulnerable to rubbing off leading to tyres with no identification marks.

It is known to provide a tyre with a transponder, sometimes called a 'tyre tag", which contains information about the tyre stored on a chip. The tyre tag can be interrogated by an external reading device, for example mounted in the road or held in the hand. Examples of known systems are described in US 4, 911,217 and EP 505 905.

A disadvantage of known road mounted systems is that vehicles must be brought to a fixed location for measurements to be taken. A disadvantage of known hand held systems is that the person taking the measurements must move around and underneath a truck to take 24 95alvI 20 October 1999 measurements from all tyres.

According to an aspect of the present invention there is provided a device for reading a tyre tag mounted in or on a tyre of a vehicle, the device comprising a reading head, a handle, and an elongate shaft connecting the handle to the head, the reading head having means for emitting an electromagnetic field and for receiving signals emitted from a tyre tag in response to the emitted field, wherein the reading head is disposed substantially normal to the longitudinal axis of the shaft.

By providing the reading head substantially normal to the longitudinal axis of the shaft, a user may take readings from a number of tyres on a truck without having to go around the truck or lie underneath the truck. The user can simply insert the shaft under the truck to a suitable location, and move the device sideways until the reading head overlaps a side wall of a tyre whose tyre tag is to be interrogated.

It is to be understood that the shaf t need not be straight; the invention encompasses devices in which the shaft may have local or general deviations from straightness providing that the device may be inserted under the body of a truck and moved sideways so that the reading head overlaps a tyre without the need for a user to move f rom the side of the truck. The longitudinal axis may therefore be interpreted as an imaginary line which, when the device is in use, will run f rom the handle substantially parallel with the wheel axles of the vehicle.

Preferably the shaft separates the handle from the head by 35 a distance to enable the shaft to span a double wheel on a 2495alv1 20 October 1999 truck axle, f or example at least around 600 mm.

It is preferred that the reading head is dimensioned so that it can be disposed between a pair of tyres which are adjacent on a truck. This optionally enables the reading head to take readings from tyre tags in both tyres simultaneously. The reading head may be disc shaped, but either or both of its surfaces may deviate from planarity.

Mudguards may interfere with insertion of the shaft, and so in one embodiment the shaft is provided with at least one arched region which enables the shaft to be positioned around a mudguard. A plurality of such arched regions, notably two, may be provided for accommodating a plurality of mudguards on a truck.

In a preferred embodiment the device is provided with electronics means for transferring data from the reading head to computer means, for example a personal computer or a palm-top device. The electronics means may be provided in the handle of the device. It is particularly preferred that the reading head also has means for uploading information into a tyre tag, for example from the same computer means used to download data from the tag. Communication between the device and the computer means may be by wireless communication, or a cable may be used to connect the device to the computer.

Accordingly, another aspect of the invention provides a tyre management system comprising a device for reading a tyre tag as set forth above, and at least one tyre tag f or mounting in or on a vehicle tyre, the tyre tag being responsive to electromagnetic signals from the reading head of the device, and having means for storing information transmitted from the device.

24 95alvI 20 October 1999 The system may optionally include means for measuring tyre parameters, f or example pressure and tread depth, and means f or electronically transmitting measured parameters to the tyre tag f or storage.

is The invention will now be further described, by way of example, with reference to the following drawing in which:

Figure 1 is a perspective view of a device f or reading a tyre tag, in accordance with the present invention; Figure 2 is a side view of the device of Figure 1; Figure 3 is a side view of an alternative embodiment of the device of Figure 2; Figure 4 is a sectional view of a further alternative embodiment of a device in accordance with the invention, in use; Figure 5 is a sectional view of the reading head of the device shown in Figure 1; Figure 6 is a sectional view along the line A-A of Figure 5; Figures 7 and 8 are, respectively, views of the top and the bottom of the handle of the device of Figure l; Figures 9, 10 and 11 are, respectively, side, front and rear views of a device for measuring tyre tread, f or use in the invention; and 2495alv1 20 October 1999 Figure 12 is a f low diagram showing screen images of a system in accordance with another aspect of the present invention.

The device shown in Figures 1 and 2 comprises a reading head 2, a handle 6, and an elongate shaft 4 connecting the head 2 and handle 6. The head 2 is flat enough to fit between adjacent tyres on a truck axle, and is disposed substantially at right angles to the longitudinal axis of the shaft. A user can therefore interrogate a transponder in a tyre on a truck by inserting the head and shaft under the truck body, alongside one or more tyres of the truck, and then move the head and shaft sideways to slip the head around the rear side wall of a tyre or between adjacent tyres.

In the embodiment shown in Figure 3, the shaft 4 is provided with an arched region 8 to enable it to fit around a mudguard. Figure 4 illustrates an embodiment in which the shaft 4 has two arches 8 to fit around two mudguards 10 associated with tyres 12 of a truck. In Figure 4, the head 2 can interrogate or send information to a tyre tag in the adjacent tyre 12, typically having a range of about 8 cm. However, by placing the head 2 between the adjacent tyres 12, readings could be taken from tags in both tyres simultaneously.

Referring now to Figures 5 and 6, the reading head 2 comprises a housing 16 which has a cover 18, formed in this example from a plastics material. The housing and cover define a cavity 14 in which is located a coil or other means (not shown) for interrogating andlor sending information to a tyre tag. The read/write means is connected by a wire which passes through a hole 20 and the 2495alv1 20 October 1999 shaft 4, to electronics means in the handle 6. Referring now to Figures 7 and 8, the handle 6 is f ormed from a top half and a bottom half which def ine a cavity 24 between them in which the electronics means (not shown) are located. The shaft 4 is received in a socket 26, through which the wire is connected to the electronics means. A switch 28 activates the electronics. The electronics is connected to an external portable computer for uploading and downloading information either by wireless communication or by a conventional cable which plugs into a socket 30 in the handle 6.

Information regarding a particular tyre may be input into the tyre tag manually via the computer, or electronically via a tool adapted for this purpose. By way of illustration, Figures 9 to 11 show a tread depth measuring device which transmits electronic tread data to a computer. The tread depth measuring device comprises a probe 34 for inserting into a tyre's tread, connected to a piston 36 in a sleeve formed from two fixed portions 38, 42. The device has a handle 32 and a cap 44 containing conventional electronics means for measuring linear displacement. In use, the face of the device is brought up into contact with an edge of the tyre, and the probe 34 is inserted fully into the tread by pushing on the piston 36. On release of the piston 36 spring biasing means cause the probe 34 to retract by a distance which is dependent on the tyre tread depth. This tread information may be transmitted to the computer and thence to the tag.

Details of a proposed computer system and its screen interface are described below, by way of non-limiting example only.

24 95alv1 20 October 1999 Data entry and maintenance The screen images shown in Figure 12 show sample images of RTM the system, as seen on the Psion Workabout LCD Screen.

After the Login screen, the System Screen will appear.

From here the choice of activity will be activated.

The tyre manufacturer might want to store some unique data to the TAG. This can be seen as the low-level formatting or data entry level for the TAG - Initialising.

The following is an Example Screen.

Manufacturer Data Entry Tyre ID: GLC21438G 16bytes Batch ID: CA6789 6bytes Type: - 2958OR22 8bytes Manufacturers Code: - XZE2 4bytes Notes: <Retreadable/Non-Retreadable> 0 At Data Entry f or TyreMan screen, it is suggested tha Haulier enters data for the vehicle the tyre is fitted to.

t Tyre ID is a parameter that should be retrieved from the Global Tyre ID Vehicle ID - Is Probably the Vehicle Registration Number (7-characters) Position of the tyre on the Vehicle - Probably Left/Right, Steer/ Drive/Trai ler, Axle No., Inner/Outer (4-characters) Manufacturer - This would be the few charactersas entered at manufacturer level - MFG Code The type of tyre is as defined in Manufacturers Screen above - Basically the Size incorporates the Type - Global Parameter 2495alv1 October 1999 An example is as follows: - Data Entry for TyreMan Tyre ID: - GLC21438G (Entered at MFG Screen) Vehicle ID: - L123ABC 8bytes (Possibilities: seven characters) Position: - <LD1I/RD1OlLS1I/LT40> 4bytes (Position as described above) Manufacturer: - XZE2 (Entered at MFG Screen) Type/Size: 2958OR22 8bytes (Entered at MFG Screen) The Inspection screen displays the Last Inspection Date as the first bit of information. The Tyre ID, is obtained from the global parameter, Vehicle ID and Position is displayed from the global variable for cross check purposes at inspection level. The Tread Depth can be measured and entered as well as the Inflation PressureIf the Repair Flag is set to Yes, then a previous repair needs to be double checked at this stage. This flag will be reset as soon as the inspection is completed and the new inspection data is stored. (A default Tread Depth and Inflation Pressure parameter is suggested with the use of arrow keys to move up or down to the correct level/value.

Left Arrow - Down & Right Arrow - UP) 2 4 95alv1 20 October 1999 An example of the Inspection Screen follows:

Inspection, Last - 22110/1999 Tyre ID: - GLC21438G (Entered at MFG Screen) Vehicle ID & Position: - L123ABC 6 (Entered at Data Entry screen) Tread Depth: - possible) Pressure: - <10/15120125/301... /15o> 150 possible) Repair Flag: - <Yes/No> (Conditions: - Yes/No) <1 /2/3/4/5/... /30> (Values of: - 1 - 30 (Values of: - 10 The Condition Report screen, deals with the visual aspects of the Inspection Procedure. Again the Tyre ID is the main relation to this data structure. The Condition of the side wall of the tyre is graded into f ive. categories. The operator only needs to choose f rom these predetermined values. If there are any comment, a range of comments would be provided in the remarks f ield. The operator again can choose f rom these Notes Summary, in order to minimise keystrokes.

An example is as follows:

Condition Report Tyre ID: GLC21438G Sidewall: <Excellent/Good/Average/Fair/Poor> lbyte SW Remarks: - <Scuffed/ Chipping/ Bulge/ Driver Alert> lbytes Crown: - <Excellent/ Good/Average/ Fair/ Poor> lbyte CR Remarks: - <Uneven wear/Wheel al ignment/ Balancing> lbyte 2495alv1 20 October 1999 - Maintenance to be carried out on tyres is categorised into two main activities. The one when Patch Repairs are undertaken, the other when Remould procedures are executed. A main screen covers the high-level maintenance report, with the facility to go in deeper into reporting on the specific maintenance activity to be performed. The Tyre ID is the main relational parameter to all tyre exercises. The iFit Pat and FRetrea being buttons to take the operator to two further screens.

An example of such a screen is as follows:

Maintenance Tyre ID: GLC21438G Repair: <Yes/No> Replace: - <Yes/No> Flag Next Inspection: - <Yes/No> 1Fit PatcR PRetre-a- Fit Repair Patch Tyre ID: - GLC21438G Tyre Type: - 2958OR22 Patch Size (SW): - <112/3/4/5/6> Patch Size (CR): - <112/3/4/5/6> Remark: - <Cold Vulcanising/Hot Vulcanising> Patch Number: - 1,2,3 Remould Tyre ID: - GLC21438G Tyre Type: - 2958OR22 CR Width & Circum: - ? Bead-to-Bead: - ? Rubber Depth: - ? 2 4 95alv1 20 October 1999 Each tyre may be provided with a unique number by means of its tag. This number can be allocated at manufacturing or as a retrofit when a device holding the number is added to the tyre. The device may be an Electronics Radio Frequency Passive TAG. (RFID TAG) The reason for passive tagging is due to the nature of the technology, which allows data to be stored on a device without the need of a power source. The device is also a wireless device, which allows the embedding thereof into numerous substrates. The communication channel provided is also the energy channel for the device. This technology is well proven and widely used in the security industry and therefore also in the motorcar industry, particularly in the vehicle immobiliser market.

The preferred tag has its own unique number from manufacturing, as well as a memory for numerous datastructures to be configured. It is proposed to use one of the secure areas on this device to store the specific and unique tyre ID number, the manufacturer's number/namel code as well as the type of tyre. This area would then be protected and can not be altered unlawfully.

company Name - Leasing Client The name of the client/haulier company leasing the tyres, can be stored on the preferred tyre tag, which will identify the specific tyre to that client. It is a good measure to ensure that tyres leased to one client does not get mixed up with tyres supplied to other clients.

Date Tyre - Supplied The purchase date, or date of installation is a good parameter to keep with the tyre history. This date is stored in a secure location on the preferred tyre tag, 24 95alv1 20 October 1999 since this might be required for warranty purposes or alike.

Vehicle - ID The vehicle registration number will be a key link to the data stored in the preferred tyre tag. It will be apparent when this document covers the Management of Tyres. Each vehicle has a certain number of tyres and also a specific set of tyres. This set of tyres will be linked to this vehicle's registration number, as well as to the position on the vehicle.

Specific - Tyre ID Each tyre will be allocated a Unique Number, which will stay with it f or the whole lif ecycle of the tyre. It is perceived that this unique way of labelling tyres will be implemented in such a way that the tyres may be remoulded, repaired or taken through any other standard practise in the tyre industry today, without damaging this device or the data stored on it.

Tyre Type There are three main tyre types that are used in the industry. The steering wheels normally have a different tyre type to that of the driving wheels or those used on trailers.

a) Steer These tyres are designed to improve traction during cornering and normal steering procedures. These tyres should therefore only be mounted on steering wheels.

b) Drive These tyres are designed to improve the traction in forward motion and perform best in these positions on 2495alv1 20 October 1999 a vehicle. These tyres should therefore be mounted on traction wheels of a vehicle.

c) Trailer Tyres These tyres are designed to improve lifetime rather than specific traction requirements. The main objective is lifetime/mileage in forward motion and performs best, mounted on trailers.

2495alv1 20 October 1999 Tyre Position on a Vehicle To keep track of tyre wear and possible problems such as wheel alignment and camber settings at specific mounting positions, each tyre gets allocated a specific position on a vehicle. The wear of the tyre will show any problems with the vehicle, which will effect the mileage achieved with the tyres. This is important for tyre management. This allocated position needs to be logged and stored in memory, for which there is provision made on The preferred tyre tag. Should a wheel or tyre be moved from one position to another, the change needs to be made by an authorised person, and the new data stored on The preferred tyre tag. Unauthorised moving of tyres to different positions would be picked up during routine inspections.

Management Inspections Tyre Leasing companies make it their number one priority to manage the tyres on lease in order to obtain the best possible mileage from these tyres. If the tyres wear out, prematurely, the Leasing Company inevitably looses revenue. If the Leasing Company can manage the tyres very well, their profit would most certainly rise due to the higher mileage achieved on these tyres.

Management of these tyres is unfortunately very labour 25 intensive and The preferred tyre tag can also offer advantages and faster turnaround times for these inspectors in order to achieve a higher productivity and therefore lower overhead costs.

Currently inspections are limited to sample inspections, 30 and even then, not all parameters can be checked. It is for instants not profitable to check the tyre pressures of all tyres during routine inspections. The minimum 2495alv1 20 October 1999 inspection boils down to a visual inspection only, with limited reporting filled in. This is all due to the time restraint and very labour intensive task that inspecting has become.

The solution that the preferred tyre tag offers, eliminates the writing or logging of parameter by hand on paper, with computer entering of the reports at a later date, as it is currently done. Inspections should require less time, therefore allow more thorough inspections to be carried out, more frequently. The preferred tyre tag gives the operator certain choices to choose, rather than typing words, and some measurements done on tyres are automatically measured and logged during routine inspections. The data can be downloaded to the main management software or computer as may be required.

Inspector - ID Each inspector should have a unique ID number. This is important to keep track of who did the inspections. It is a good tool to keep the inspections to the highest standard, which will inevitably pay off in the long term. The thoroughness or accidental mistakes can be rectified through training or alike, when problems can be pin pointed. This is currently standard practice and The preferred tyre tag will incorporate this feature too. The preferred tyre tag will store the last inspector ID for any future reference that may be required.

2495alv1 20 October 1999 Date (1) - Last Inspection but One As part of the ongoing history collection, it is important to capture two dates onto the preferred tyre tag. Although a more thorough DataBase is kept elsewhere it is important to have the Last but One Inspection Date as well as the Current Inspection Date, which becomes the Last Inspection Date logged on The preferred tyre tag.

Date (2) - current Inspection The Current Inspection Date will be entered and stored 10 automatically when a new inspection has been performed. Certain controls will be in place to ensure that bogus inspections cannot easily be entered in order to erase previous inspection data. This date will be stored as Last Inspection Date, on completion of an inspection.

Vehicle - ID The vehicle ID will be representing the Vehicle Registration Number. It will be inter-linked to the tyre details, so that the vehicle and all its tyres will form part of a relational database. The vehicle being the main 20 body.

Tyre - ID Each tyre will have its own unique identification number, as issued by the manufacturer or in some cases the Leasing Company. With the correct authority, it will provide the Actual and Lawful Owner of the tyre the facility to have its own Unique ID being issued and stored on the preferred tyre tag.

Mileage CoMpleted - Reading The mileage of the vehicle will be recorded although this 30 cannot be verified and the inspector will have to enter 24 95alv1 20 October 1999 this value manually. It is possible to keep the mileage of the vehicle, therefore the mileage of the specific tyre, on the preferred tyre tag. Due to the limited storage space, it might be feasible to store only whole-thousand readings, for example: - 10000 miles will be represented as 10.

Tyre condition The inspector needs to examine the tyre for any defect or damage caused by road hazards. These might be to the side- wall, or the tread-area. Cuts, bulges and uneven wear are the main concerns.

a) Tread Depth Depending on the type of tyre the depth on new tyres can vary from 21 mm to 15 mm. The lowest depth however is more or less the same on all tyres and is in the region of 2mm. The inspector uses a manual depth gauge to determine the tread depth remaining on a tyre, log the reading manually on paper for future data collection onto a computer at a later date.

It is proposed that a measuring device should form part of the inspection tool, where the measurement of the tread depth will still be measured manually, but that the measuring indicator firstly display the measured depth and then log the measurement into a handheld terminal. This value is now already collected electronically and the data can be transferred to The preferred tyre tag andlor to the main database as required.

b) Inflation Pressure The inflation pressures of truck tyres are in the region of 150 psi. It is perceived that a 10% tolerance might be acceptable. The inspector measures the inflation pressures, and the value is currently manually recorded for later entry onto a database.

2495alv1 October 1999 It is proposed that the pressure measurement device f orm part of the logging instrument. The actual measurement of pressure however still needs to be administered by hand, but the pressure reading will be displayed and stored automatically on the reading instrument, which then logs the parameter for transfer to The preferred tyre tag and/or the database on any computer system as might be required.

c) General Condition The general condition of the tyre is something that the trained eye of an inspector is best to determine. It is not feasible to build this delicate operation into any computer system, since the cost of image analysis for this task is far too high at present. However the proposal does want to cover this possibility, as computer power and cost are dropping this will very much be the perfect opportunity to incorporate this function as an automated inspection.

i) Tread The general tread condition is inspected. Should there be uneven wear of the tread, possibly due to problems with the wheel alignment of the vehicle as well as possible camber adjustment problems on the vehicle, it will be noted and rectifying work can be initiated.

A few choices/categories are suggested to cover these possible scenarios as ease of choice on the inspection terminal. Possibly as follows: -GOOD EVEN WEAR, AVERAGE EVEN WEAR, POOR EVEN WEAR, GOOD UNEVEN WEAR, AVERAGE UNEVEN WEAR or POOR UNEVEN WEAR.

ii) Side-Wall The general condition of the side-walls is inspected for cuts, bulges or other damage. A suggestion for condition reports might be fairly simple, possible: - GOOD, SCUFFED, 2495alv1 20 October 1999 CUT, BULGED, POOR.

Re-works As in all industries there are periodic maintenance on tyres. It is crucial to build this history for performance analysis etc. When any work is done on a tyre, The preferred tyre tag can store important information. These might be puncture repairs, when, how many etc. When tyres are swapped from various positions on the vehicle, a small history of previous positions are recorded as part of the life cycle of the specific tyre. It is particularly important to track the history of a tyre when tyres are moved from one vehicle to another.

Replacement When a tyre is replaced on a vehicle, the reasons f or 15 replacement is stored on the preferred tyre tag, in order to feedback the required reasons for replacing the tyre, which can be premature. This will be. stored on the damaged/old tyre, as well as possibly recorded on the replacement tyre, should this be one, rather than a set of tyre change.

1. Ad Roc Inspection There is a need f or ad hoc inspections to determine any possible problems with non-approved tyre replacements or removals. It will then be a case of checking the tyre ID against the Position ID and Truck/Vehicle ID. Various parties, including the law enforcement bodies could do or find the need for these inspections.

2. Life-ectancy Porecast There are existing computer programmes that tyre 30 manufacturers have developed to forecast tyre life expectancy. These programmes however require routine 2495alv1 20 October 1999 feedback from inspection sheets. The aim of the preferred tyre tag system is to optimise the data collection process, in order to make it viable to inspect tyres on vehicles and trailers more regularly. The frequency of inspections is important, in order to feed an abundance of data to these forecasting and analytical software packages, which in turn will be able to return realistic lif e expectancy values to the tyre management companies. The benef it to the Tyre Leasing Company would be to have advance notice and warning to prepare the replacement of tyres well in advance of actually having to do this. Routine replacements can then be planned for to streamline the actual activity.

P SYSteM main Functions a) Inspection Terminal - Tool Handheld/Palmtop computer or terminal, that will be able to communicate with the preferred tyre tag, through the tyre side-wall andlor tread surface. The terminal will be simplistic to use and dedicated to the tyre management industry. The functionality will be to read the required data from the preferred tyre tag, update changes, measure TyreWear and Inflation Pressure with automatic updating of these parameters to the memory of the terminal, and if required, to write the updated parameters back to memory onboard The preferred tyre tag. The terminal will have specific characteristics and functions to down load the captured data to a Tyre Management Software Package via a communications interface, such as an RS232 serial interface. This will ease the integration of the preferred tyre tag system to existing Tyre Management Systems.

2495alvI 20 October 1999 b)Inspector Identification The software on the terminal will require a password/ username to be entered which is unique to each inspector. This will allow the logging/tracking of specific inspectors to each inspection.

c) Tyre identification By reading the tyre ID from the preferred tyre tag, the tyre will be identified, linked to the vehicle and its Registration Number, as well as the position on the vehicle where the tyre should be mounted. d) Vehicle ID The inspector can enter the Vehicle Identification or

Registration Number, to check tyre details linked to the vehicle. However the recommended procedure would be to read any tyrelthe tyre tag on the vehicle, which should identify the vehicle registration number, for cross check. This procedure will eliminate and minimise the need of entering keystrokes on the terminal.

e) Tread Depth Measurement It is proposed that a hand-operated tread depth gauge be implemented as part of the terminal. The inspector will still determine the position of measurement to secure appropriate positioning of the measurement of tread depth, the reading of the depth gauge will be done electronically and automatically stored on the terminal. It is suggested that the inspector be lead through a sequence, such as: Outside measurement, Centre Measurement and Inside Measurement. The measured depth will be displayed to the inspector, before storing the value. It might only require the storing of the worst depth measured. The storing of the value will be performed through a single keystroke, as soon as the inspector is satisfied with the specific 2495alvI 20 October 1999 measurement routinelprocedure. This will allow the inspector to check whether the depth measured seems reasonable to eliminate the storing possible fictitious values.

f) Inflation Pressure Measurement Provision is made for an inflation pressure measurement, as part of the terminal unit. The inspector will still have to connect the unit to the tyre inflation valve, but the measurement will be registered automatically with an option to store the value. The storing of measured values will only occur when the inspector feels it appropriate and he/she is satisfied that a good/proper measurement has been taken. Again the storing of the data will be performed following a single keystroke.

Principle of operation The Reader/Terminal will identify the tyre, by interrogating the tyre tag. As soon as communication is established with the tyre tag, the terminal will display the tyre ID, as well as the Vehicle Registration number of the vehicle it should be installed on. A graphical indicator will identify the position of the tyre on the specific vehicle, this feature is to allow cross referencing the vehicle ID. The opportunity to measure the tread depth as well as the inflation pressure will be handled automatically. This means that the operator would not need to do the inspection in any specific order.

Instead the terminal will monitor the inspector's actions and follow these actions. A flow diagram is attached to explain the possible flow of events. This means that the 2495alv1 20 October 1999 inflation pressure can be measured, followed by the tread depth measurement, before the inspector has to do any thing on the terminal. After these actions have been completed, the values will be displayed on the terminal automatically and accepted unless specifically cancelled by the operator. Should the operator be unhappy with the operation of depth measurement or pressure measurement, tlm,ae operations can.---be. initi at....time WIth- the procedure starting automatically as described above. The terminal will override the previous values until the inspector accepts the values. Only then will these values be stored on the terminal. These values will only be transferred to the tyre tag, once all possible parameters has been successfully updated on the terminal. (Pressure, Tread Depth, Condition etc.) The operator would need to do the visual inspections and for this operation a sequence is suggested. A default value will be assumed, although the inspector can make changes to the descriptive values as found most appropriate to the actual condition of the tyre. These values are changed by single arrow key operations, typically UP/DOWN and LEFT/RIGHT arrow keys as experienced on Personal Computers.

It is estimated that the inspection time can be cut to approximately a quarter of the time spendduring conventional methods.

2495alvI 20 October 1999 24

Claims (18)

Claims

1. A device for reading a tyre tag mounted in or on a tyre of a vehicle, the device comprising a reading head, a handle, and an elongate shaft connecting the handle to the head, the reading head having means for emitting an electromagnetic field and for receiving signals emitted from a tyre tag in response to the emitted field, wherein the reading head is disposed substantially normal to the longitudinal axis of the shaft.

2. A device as claimed in Claim 1 wherein the shaft is straight.

3. A device as claimed in Claim 1, wherein the shaft has local or general deviations from straightness.

4. A device as claimed in any preceding claim, wherein the shaft separates the handle from the head by a distance to enable the shaf t to span a double wheel on a truck axle.

5. A device as claimed in Claim 4, wherein the distance is at least around 600 mm.

6. A device as claimed in any preceding claim, wherein the reading head is dimensioned so that it can be disposed between a pair of tyres which are adjacent on a truck.

7. A device as claimed in any preceding claim, wherein the reading head is disc shaped.

8. A device as claimed in any preceding claim, wherein the shaft is provided with at least one arched region which enables the shaft to be positioned around a vehicle mudguard.

9. A device as claimed in Claim 8, wherein a plurality of such arched regions are provided for accommodating a plurality of mudguards on a truck.

10. A device as claimed in any preceding claim, including electronics means for transferring data from the reading head to computer means.

11. A device as claimed in Claim 10, wherein the electronics means is provided in the handle of the device.

12. A device as claimed in any preceding claim, wherein the reading head also has means for uploading information into a tyre tag.

13. A device as claimed in Claim 12, wherein the uploading means uploads data from the same computer means used to download data from the tag.

14. A device as claimed in any one of Claims 10 to 13, wherein communication between the device and the computer means is by wireless communication.

15. A tyre management system comprising a device for reading a tyre tag as claimed in any preceding claim, and at least one tyre tag for mounting in or on a vehicle tyre, the tyre tag being responsive to electromagnetic signals from the reading head of the device, and having means for storing information transmitted from the device.

16. A system as claimed in Claim 15, including means for measuring tyre parameters, for example pressure and tread 26 depth, and means for electronically transmitting measured parameters to the tyre tag for storage.

17. A device for reading a tyre tag mounted in or on a tyre of a vehicle substantially as herein described with reference to and as shown in the accompanying drawings.

18. A tyre management system substantially as herein described with reference to and as shown in the 10 accompanying drawings