AU4464099A - Warning device - Google Patents

Description

I

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT *4e Name of Applicant: Actual Inventor(s): Address for Service: Invention Title: ALEXANDER PHILLIP CALDWELL ALEXANDER PHILLIP CALDWELL CULLEN CO., Patent Trade Mark Attorneys, 240 Queen Street, Brisbane, QId. 4000, Australia.

WARNING DEVICE

S

S. S 0 55 Details of Associated Provisional Applications: No. PP5366 filed on 20 th August 1998 The following statement is a full description of this invention, including the best method of performing it known to me.

WARNING DEVICE TECHNICAL FIELD This invention relates to a warning device.

More specifically this warning device is for use on a vehicle to warn when a predetermined speed is being approached or has been exceeded.

BACKGROUND ART With suburban speed limits being generally at 60 kilometres per hour and highway speed limits at 100 kilometres per hour it is very easy for a 10 sober and level headed driver to exceed the speed limit prescribed for any oooe e road. This situation is exacerbated by modern vehicles which because of *their technology provide an incredibly smooth ride which creates the impression that the vehicle is going slower than it actually is. It is neither 00:**practical nor desirable for a driver to constantly look at the speedometer while they are driving a motor vehicle as their primary duty is to keep their eyes on the road. With increasingly sophisticated means of detecting speeding vehicles, and with severe penalties in the form of fines and demerit points threatening driver's licences, even very competent drivers can find their livelihood threatened by an unlucky run of speeding infringements.

Accordingly it would be advantageous if a means could be devices for warning a driver that they were maintaining or exceeding the S•speed limit or a speed that they have previously decided is appropriate in the circumstances.

Further car theft is on the increase world-wide. With the increasing sophistication of car thieves existing anti-theft devices such as steering locks and alarms are becoming less efficacious all the time.

Accordingly it would be advantageous if a new improved device for resisting the theft of motor vehicles could be devised.

DISCLOSURE OF INVENTION According to an aspect of this invention there is provided a warning device for use with motor vehicles, the device including: Means for sensing the speed of a vehicle on a road or support surface; Means for issuing a warning signal; and Processing means for receiving the sensed speed from the sensing means, comparing the sensed speed with a pre-determined speed, and if appropriate causing the warning signal means to issue an appropriate warning signal.

Typically the warning signal means issues an audio signal and/or a visual signal, eg an audio alarm in the form of a beeper and a visual signal in the form of an LED. Preferably the audio beeps intermittently and the LED flashes until the vehicle slows down to the predetermined speed.

Typically the processing means is a central processing unit (CPU), eg a micro-CPU mounted on a PC board.

Optionally the warning signal means may issue a plurality or a series of warning signals including a main warning signal.

Naturally the warning device also includes means for setting the predetermined speed, eg in the form of an interface. Typically the setting means includes means for setting a basic speed setting and also means for setting a margin speed setting. Typically the margin setting sets the margin above the basic speed setting at which the driver can travel before the device issues a main warning signal.

Typically the device will include a housing within which the S0processing means and the warning signals are housed and the interface is provided on the front face of the housing and comprises a keypad for entering the basic speed setting and a rotatable knob having specific positions for different settings for entering the margin speed setting.

Preferably the speed setting means permits the basic speed to be set at the following speeds, eg 60 kph, 80 kph or 100 kph.

Preferably the speed setting means permits the margin setting to be set at the following margins above the basic speed setting eg 2 kph, 6 kph, 10 kph, 14 kph, 28 kph and 42 kph.

Thus typically a driver will select a basis speed setting corresponding to the speed limit on that particular road and then set the margin setting at a level they desire above the basic speed setting. Thus, eg in a 60 kph zone, the driver might set the margin setting at +2 kph in which case the yellow LED will flash and sound its main warning signal when the driver reached a speed of 62 kph. Additionally the buzzer may sound an unobtrusive signal at 2 kph below 62 kph and an intermediate signal at 1 kph below 62 kph or at any other intervals preset by the manufacturer or the vehicle owner. Naturally it would be inappropriate for the driver to set a speed of 102 kph in a 60 kph speed zone.

Typically the yellow LED would only flash when the main warning signal was activated. Typically switching the buzzer to off would o silence the buzzer but the yellow LED would continue to flash.

*00 Optionally the warning device also includes means for resisting the theft of the vehicle.

Typically the theft resisting means comprises: A switch in the ignition wiring which moves between an open position permitting current flow and a closed position preventing current flow through the ignition wiring; Processing means for comparing an entered coded with a preset code and responding to a correct match by moving the switch to the closed position; and means for entering the code into the device.

Typically the processing means for the theft resisting means is S"the same as the processing means for processing the speed of the vehicle, eg a CPU.

Typically the theft resisting means is armed when the vehicle ignition is switched off.

The theft resisting means is disarmed when the security switch is switched off and a disarming code is entered into the processing means.

Typically the entering means comprises a keypad, eg the keypad described above for entering the basic speed setting. Typically the rotatable knob on the keypad has a position to set the security switch.

Typically the device also includes means for energising the device, eg in the form of a vehicle battery.

Typically the CPU can store a pre-set code indefinitely or the device includes a capacitor or other backup power source to provide power to the device for, eg 10 minutes, in the event that the vehicle battery is disconnected. If the battery is disconnected for longer than this period, the relevant information may need to be re-entered into the device. However a new code can only be entered after a device security number (DSN) specified by the manufacturer has been entered.

In one embodiment the device does not include theft resisting means but instead has a dummy visual indicating means, in the form of a red flashing light, which can be activated to create the impression of a theft resisting means.

Naturally the housing will be of a size suitable for mounting on or near the dash board of a motor vehicle.

Advantageously the housing will include means for mounting the housing on the dash of a vehicle, eg in the form of a mounting flange or mounting bracket.

Optionally the device also includes means for assessing a drivers capability before he/she starts the vehicle. Typically the driver *..,-capability assessing means comprises an add on feature to the theft resisting means described above.

Typically the driver capability assessing means comprises a S°reasonably intricate routine involving data which the driver has to enter into the device via the keypad before the ignition system is enabled.

In one form the routine comprises entering a code which is a sequence of numbers several times on a keypad in forward and reverse order.

The purpose of the routine is to prevent a vehicle from being started if a driver is intoxicated or the like.

Optionally the device also includes means for warning a driver when certain engine operating parameters move outside of normal operating range. Typically such operating parameters include oil pressure, temperature, alternator function, or brake fluid level.

IIC/ 1 -11~ 1~ 1 11 1 11 *ll lil- 11 ~II- llll i l*Il L~il-l_ il- ll l 1I 1 1*1 I1 1 I- ll-l I~L~ l_1- -~111 ~-11(-11 1 Typically the device will include an LED for each parameter being measured and the relevant LED will light up and the buzzer will sound to warn a driver if the parameter moves outside the predetermined range.

Typically the buzzer can be switched off but the LED will remain illuminated until the problem is rectified.

A warning device in accordance with this invention may manifest itself in a variety of forms. It will be convenient to hereinafter describe in detail one preferred embodiment of the invention in detail with reference to the accompanying drawings so as to instruct persons likely to have an interest in the subject matter of the invention how to perform the invention. In the drawings: Figure 1 is a schematic front view of a control panel for a warning device in accordance with the invention, and Figure 2 is a table showing how the calibration constant is calculated for the device and how this varies for a range of vehicle types, and Figure 3 is a table showin? how AutoSet and KnobSet models 0- 4l1C I S O of the present invention can be set, and Figure 4 is a table showing how the AutSt and KnobSet I V, l ,1G, 11 '5 07 models of the present invention can be feteF setFand vllf iI "l Figure 4A is a table of speeds at which beeps will sound at *oo* various optional settings when the set speed is 60kph, and Figure 5 is a schematic drawing of relating componentry for a KnobSet version of a device according to the present invention.

With respect to figure 1 of the drawings, the vehicle device can comprise broadly a sensor (SSU), a processing means which is a CPU, and means for issuing a warning signal which includes a buzzer and a visual warning signal such as a yellow coloured LED.

The sensor measures the speed of the vehicle and comprises a device for timing/counting the revolutions of either a vehicle drive shaft or a wheel of the vehicle. In one particularly suitable form the sensor counts the number of revolutions of the shaft from the number of magnetic pulses generated by a magnet mounted on the drive shaft. In another form the fXII11 ~XIIII l ~i ll~i1 111 1 l ~ll l~ l~ill 1 11 1 11 1 1^ 11 111 I 1 *I I~ L ~~lllr~--X ~II- I~ I device counts the number of revolutions from the number of reflections of a light source made by a piece of reflective tape stuck to the drive shaft. The sensor type will be capable of sensing all drive shaft speeds in the range of 100 8,000 rpm. It will however be understood by all persons skilled in the art that while the above two methods of sensing speed are particularly suitable, they are not essential features and that other ways of sensing the vehicle speed may be employed.

The processing means or CPU receives a measure of the speed of the vehicle from the sensor. The processing means comprises a microprocessor on a PC board.

The device also includes speed setting means for entering the appropriate information into the device in the form of an interface. The .:og interface comprises broadly a housing having a leading surface which is a control panel on which a rotatable knob and a keypad is mounted as shown in figure 1. The CPU, various LED's and buzzers may also be contained in the housing or else in a separate housing or concealed in the vehicle dash.

The keypad enables a basic speed setting to be entered into the CPU. In the illustrated embodiment the basic speed setting can be set from to 110 kph. Keys 3 to 9 indicate respectively 30-90 kph, key 0 indicates 100 kph and key 1 indicates 110 kph. Of course the keypad labelling can be enhanced or rearranged to show the full representation of speed settings in S"kph or mph.

The rotatable knob enables the margin speed setting to be entered into the CPU. As shown in figure 1 the margin speed setting can vary from +2 kph to +42 kph.

For more aesthetic mounting in various vehicles, other variations of the device could use a second rotatable knob instead of the keypad or could use one rotatable know instead of the keypad plus a fixed margin instead of the rotatable knob for various margin settings. Another variation may have no keypad or knob but would memorise any speed that had been constant for a period of five seconds and would sound the various warnings when that speed was exceeded.

The device also includes theft resisting means in the form of a switch connected in series with the ignition wiring and processing means which is provided by the CPU for comparing an entered code or vehicle security number (VSN) with a pre-set vehicle security number and closing the switch if the entered and pre-set numbers correspond. The theft resisting means also includes means for entering the vehicle security number into the device which is provided by the keypad.

The vehicle security number is a pre-set digit sequence, typically 4 digits, which is entered by the numerical keys on the keypad.

In use if the device is for example being used in a 60 kph zoned, the driver enters 60 kph into the basic speed setting by pressing key number 6. The driver then enters the margin speed setting by an appropriate rotation of the rotatable knob. The actual setting is a matter of discretion. However for a 60 kph zone an appropriate margin speed setting would probably be +2.

This would then cause the buzzer to sound the main warning speed when a speed of 62 kph was attained. If however a margin speed setting of +14 was entered the buzzer would sound the main warning signal at a speed of 74 kph.

Additionally the buzzer could sound an unobtrusive signal at 2 kph below the main warning speed and an intermediate signal at 1 kph below the main warning speed or at any other intervals preset by the manufacturer or vehicle owner. The yellow LED would only flash when the main warning signal is activated. Switching the buzzer to OFF would silence the buzzer but the yellow LED will still flash whenever the vehicle is travelling at or above the main warning signal speed. The red LED would shine whenever the buzzer is switched OFF.

When the driver parks and leaves the car, he/she sets the rotatable knob to "security set" and the CPU moves the ignition switch to the open position so that current cannot flow through the ignition system to generate spark and arm the theft resisting means. Naturally therefore in this condition the engine cannot run. In addition a red LED flashes on the device to indicate the theft resisting means is armed.

i~ll_~ 111 _~11 1 11 1 1 1- 11-- -~11 1-1 -1 11~ 11* 11 1111 i- *ll lli-nnl~-i~- li-rl I. I111I If a potential car thief gains access to the motor vehicle, they will not be able to start the engine until they have entered the VSN on the keypad. Naturally unless they have knowledge of the number they won't be able to do this.

By contrast when an authorised vehicle driver gets back into the car, they turn the rotatable know off "security set" then enter the correct code or number on the keypad which enables the ignition system to permit the car to be started. The driver then enters appropriate basic and margin speed settings in the manner described above before driving off.

Naturally the device will have to be calibrated. The relationship between the RPM of the drive shaft (or wheel) and the speed of the vehicle will be constant for any particular vehicle. The device will thus be calibrated when it is first fitted to a vehicle to establish the calibration constant for that particular vehicle.

-With respect to figure-2 of the drawings, the devi can b calibrated a& followa: The margin knob is set to and the speed limit key for kph. The vehicle is then driven at precisely 60 kph (10 50) as indicated by the vehicle's speedometer (or a Dynamometer if greater accuracy is desired) and then the Calibration Button is held down for at leave five seconds until the alarm sounds to indicate that calibration has been completed and the calibration constant is stored. If the microprocessor can be programmed to allow calibration at any selected speed limit setting (rather than just at 60 kph) then this may be more convenient in some circumstances. By calibrating against the vehicle's speedometer. Ideally, provision could also be made in the programming for the calibration constant (as determined by calculation from the vehicle's "WHEEL CENTRE HEIGHT" (WCH) and its "DIFF RATIO" to be entered via the keypad. Vn this case the necessary data could be entered by holding down the Calibration button when the vehicle is stationary and the concealed button at would be used as the digit This method is independent of the vehicle's speedometer and should be much more accurate provided the wheel centre height can be 9F) o -2 d,'y S-oU) 40W 4° K (v4 4 05. olCv"-- bv, r..o 4,lr La C L1 I'fcCtc.

II I I I accurately measured and the Diff. Ratio can be found in the specifications section of the vehicle handbook or workshop manual.

A summary of the terminology used is provided below. This is to be considered in conjunction with figure 2.

Margin speed Speed set by Rotary Switch Keyed Speed Speed set by Keypad Warning Speed Margin Speed Keyed Speed i.e.

(W M K) First Signal Speed Warning Speed 2 kph i.e.

(F=W-2) Second Signal Speed Warning Speed 1 kph i.e.

(S=W-1) Wheel Centre Height (WCH) is the vertical distance in millimetres) measured from the road surface to the centre of a driving wheel when the vehicle is stationary on a level surface with normal tyre pressure and normal load. If the wheel centre cannot be accurately defined, WCH also equals the distance from the road surface to the top of the wheel rim less half the diametre of the wheel rim.

Diff. Ratio (DR) is usually listed under "Specifications" in the vehicle handbook or workshop manual and is usually expressed in a form :such as: "DR:1" eg "4.375 or "3.476 It may also be expressed as a ratio of the number of teeth in the vehicle differential such as: "35 or In this case the larger number divided by the smaller number will give the Diff Ration in the "DR" format eg 35/8 4.375.

Calibration Constant 2652 x Diff. Ratio/Wheel Centre Height ie 2652.58 x DR/WCH).

Wheel or Driveshaft Revs Per Minute RPM as determined from the SSU.

Vehicle Speed RPM/Calibration Constant ie (V R/C).

If Vehicle Speed First Signal Speed ie then First Buzzer Signal is activated.

If Vehicle Speed Second Signal Speed ie then Second Buzzer Signal is activated.

If Vehicle Speed or> Warning Speed ie0V or> then Warning Alarm Buzzer is activated and yellow warning LED flashes.

If the Buzzer is switched off, the red LED switches on while the yellow warning LED flashes if the vehicle speed is greater than or equal to the warning speed.

When the Calibration Key is held down while driving, a new Calibration Constant is calculated by C=R/W as the vehicle is driven at the Warning Speed as indicated by the vehicle speedometer.

When the Calibration Key is held down while vehicle is stationary and the Knob is set to "OFF", a new Calibration Constant can be 0090 entered via the Keypad as six consecutive numbers assuming the decimal i**O .4:1 point comes after the second digit entered. Eg 44.2097 is keyed in as .*"442097 and 8.84 is keyed in as 088400. In this situation, the microprocessor is programmed to recognise the concealed button at as representing the "digit When the Knob is switched to "Security set", and the current VSN has been correctly entered on the keypad, holding down the concealed button at will cancel the current VSN and the next set of numbers pressed 20 while remains held will become the new VSN.

00i0 wo. The device of the present invention can be made available in two different models: "AutoSet" and "KnobSet".

The AutoSet Model is the easiest to fit and operate because the only visible hardware that needs to be within easy reach of the driver is a single CONTROL BUTTON which can be neatly fitted to any vehicle. It is designed to automatically SET to the nearest ten kph setting whenever the vehicle is driven at STEADY SPEED for approximately six seconds all speeds in the 56 to 65 kph RANGE will cause 60 kph to be SET). The definition of "STEADY SPEED" is that the VEHICLE SPEED is relatively constant when compared with normal ACCELERATING SPEED and DECELERATING SPEED. Once a SET SPEED is determined for any 12 kph RANGE, it will be retained for as long as the VEHICLE SPEED remains within that RANGE irrespective of whether the speed is steady, accelerating or decelerating. Whenever the VEHICLE SPEED goes outside that RANGE, the micro processor will check to see if the vehicle is still at a STEADY SPEED. If it is, then the current SET SPEED will be retained and a WARNING will be sounded if appropriate. If the speed is outside the STEADY SPEED, then the micro processor will assume that the driver is deliberately changing speeds and SET SPEED will be re-set to the STANDBY SETTING until the vehicle again travels at a STEADY SPEED for six seconds or more and a new SET SPEED is determined. The STEADY SPEED FACTOR and STEADY SPEED INTERVAL are pre-set at the factory but an alternative value can be chosen by the user from either a low sensitivity or a high sensitivity option stored in the programme.

The automatic functions of the AutoSet mean that the driver has minimal physical controls to worry about and only needs to look at the speedo 15 momentarily when adjusting to a changed speed limit before the AutoSet takes over and sets that speed limit into its memory as the SET SPEED.

Whenever a SET SPEED is determined, an appropriate series of SPEED INDICATOR BEEPS can be sounded to indicate the value of the speed that has been SET, if that option has been chosen by the user. In order to 20 minimise unnecessary beeps, the factory settings exclude SPEED INDICATOR BEEPS. Any time that the Control Button is pressed once momentarily, the AutoSet Model immediately reverts to STANDBY SETTING so that no warning beeps will be heard until the vehicle is again driven at a STEADY SPEED and AutoSet determines a new SET SPEED. This MANUAL STANDBY allows the driver to easily CLEAR the SET SPEED and silence the ALARM instantly at any time if desired.

In most cases the conservative driver does not have to modify existing driving habits at all and with factory settings of the device they would probably only hear the warning beeps during times of gradual increase of speed due to driver inattention or on downhill grades. These are BENEFICIAL WARNINGS as they warn the driver that they are exceeding the speed limit and they are at risk of being penalised. In some cases a I driver may accelerate so slowly that FALSE SET SPEEDS are established and FALSE WARNINGS may occur. In these cases the driver simply has to press the button momentarily to set the MANUAL STANDBY. If they find this to be a consistent problem then they will need to vary the STEADY SPEED FACTOR or STEADY SPEED INTERVAL although this may increase the risk of BENEFICIAL WARNINGS being missed.

The more assertive driver can make good use of the CRUISE SIGNALS and/or RISK BEEPS if they want to push the limits. Because the AutoSet is designed to automatically SET to the nearest ten kph setting, it becomes impractical to drive consistently at steady speeds in the top half of a decade 66 to 69 kph) because the AutoSet will reset up to the next ten.

:i This limits the use of the 8 and 10 margin settings unless they are used with RISK BEEPS as the preliminary warning. The higher margin limits will only be of use when using the MANUAL MODE or the KnobSet Model.

S* 15 The AutoSet also has a MANUAL MODE which allows the driver to override the AUTOMATIC MODE and lock in a SET SPEED which will be retained as FIXED SPEED until it is manually removed. This is achieved by pressing the Control Button twice in quick succession. The first press will SET the STANDBY SETTING and the second press will instantly lock in the lo..

20 nearest ten kph setting as the FIXED SPEED. This FIXED SPEED can only be cancelled by a single momentary press of the Control Button which will SET the STANDBY SETTING and then allow future settings to be made automatically or two quick presses which will lock in a new FIXED SPEED which will be the nearest ten kph to the then current speed. When a speed zone changes from 60 to 80kph, the button is pressed once to silence warnings while the vehicle accelerates from 60 and is then pressed twice +o e& IO kfh while travelling between 76 and 85kph'as the new FIXED SPEED. When the speed zone changes from 80 to 60kph, the driver slows to any speed between 56 and 65kph then presses the button twice to set 60kph as the new FIXED SPEED.

The AutoSet Model can consist of: 1. A Control Unit which includes the Micro Computer and I I II I other hardware which are all mounted in a box which measures only 90 x 56 x 32mm (3 /2 x 2 x 1 and can be mounted out of sight under the dash or in the engine compartment.

2. A Sensor Unit which consists of a stationary electronic device which senses a magnetic field whenever it is passed by a magnet fixed to a drive-shaft of the vehicle. Each revolution is transmitted to the Control Unit as an electronic pulse where the microprocessor is then able to compute the actual speed of the driveshaft. The Sensor Unit is necessarily mounted beneath the 00:0 10 vehicle for rear wheel drive vehicles and in the engine compartment for front wheel drive vehicles. The sensor unit may not be needed on vehicles that have electronic speedometers as the device may be directly connected to the vehicles speed sensor signal output.

15 3. A Control Button and Buzzer which can be mounted either separately or alongside each other in a spareplate available on many vehicles or else the button can be mounted in the dash or steering console via a 6mm hole. The buzzer can best be mounted behind the switch plate or dash with S 20 double sided tape and requires only a 4mm hole to allow the sound to pass through. One or two LEDs can also be mounted in the dash to provide visual warnings if desired.

The KnobSet Model can have the same components as the AutoSet plus a KNOBSET MODULE which consists primarily of a Rotary Switch with Knob which can be mounted in the steering console or dash through a 9.5mm hole. This Knob allows for any speed limit from 20 to 120 kph in multiples of ten kph to be set at any time and that setting will be retained until the Knob is changed by the driver. There is also an OFF position which switches off all warning beeps. This is equivalent to the STANDBY SETTING as used in the AutoSet Model. The rotary switch has twelve positions starting with the most anti-clockwise position as 20 kph and the most clockwise as OFF.

i 1 _11 1 lr 1~11 1 11* i l ~l 111 1~ nll- 11~111 ~LII- -lr l I I ~11I 1I11 l C I111 I1~ ~I i I_ ll- I~X l rli I 1^1 1~ 1I~ I I- I_1 l The KnobSet Model gives the driver far more control over the device than does the AutoSet Model but it may be a little more difficult to fit and it requires the driver to physically reset the Knob each time they pass into a different speed limit zone. Whenever a Knob Position is changed, an appropriate series of beeps may sound to indicate the value of the speed that has been SET. The big advantage of the KnobSet is that it allows the driver to set and drive to a speed setting without ever having to take their eyes off the road.

For uniformity of operation, both Models share components, 10 terminology and programming steps and values as far as possible and the AutoSet Model is considered as the PRIMARY MODEL. The KnobSet Model simply creates a manual over-ride of the SPEED SET functions of the AutoSet Model but still uses the CONTROL BUTTON and BUZZER to S.communicate with the CONTROL UNIT for purposes of calibration, changing 15 default settings and switching signals ON or OFF. An AutoSet Model already supplied or installed in a vehicle can be changed to a KnobSet Model simply by installing a KNOBSET MODULE and connecting it to the existing Control ooo.

Unit.

Once the device is property fitted and calibrated, the Control .00 20 Unit will constantly monitor the VEHICLE SPEED and then compare this value with the WARNING SPEED or its derivatives. It should be noted that the SET SPEED, which is always a multiple of ten kph, does not necessarily activate any signals or alarms. SET SPEED is only used to determine or change the WARNING SPEED and all signals and alarms are then relative to the WARNING SPEED.

WARNING SPEED equals the SET SPEED plus the WARNING

MARGIN.

WARNING MARGIN is set at 6 kph in the factory but it can be changed to 2, 4, 8, 10, 14, 28 or42 kph by the user while driving.

RISK SPEEDS equal the WARNING SPEED less the RISK

MARGINS.

RISK MARGINS are set at 1-4 kph in the factory but can be M-M. changed to 1-3 kph or 1-5 kph by the user when the vehicle is STATIONARY.

CRUISE SPEEDS equal the lowest RISK SPEED less the CRUISE MARGINS.

CRUISE MARGINS are set at 1-3 kph in the factory but can be changed to 1-2 kph or 1-4 kph by the user when the vehicle is STATIONARY, e.g. with factory margin settings, when the SET SPEED is 60 kph, the WARNING SPEED is 66 kph, the RISK BEEPS would be heard when travelling at speeds 62, 63, 64 or 65 kph and the CRUISE SIGNALS would be heard at speeds of 59, 60 or 61 kph. Figure 4a shows other combinations.

There are five types of signals given by the device.

MINI BEEPS these are two very short beeps used only as CRUISE BEEPS because they are audible but unobtrusive.

SHORT BEEPS this is used singly or in multiples to indicate Knob position or the speed that has been set by AutoSet (SET SPEED o 15 INDICATOR BEEPS). Two SHORT BEEPS are used as the RISK BEEPS.

SHORT BEEPS are also used as prompts for entering USER DEFINABLE VALUES with multiples beeps being used in pairs or a pattern similar to the SET SPEED INDICATOR BEEPS.

LONG BEEP this is used singly, in multiples or in combination 20 with SHORT BEEPS to indicate Knob position or the speed that has been set by AutoSet.

VERY LONG BEEPS for UNCOMMON WARNINGS such as VEHICLE MALFUNCTIONS or lights left ON.

CONTINUOUS BEEP this is only used as the WARNING ALARM when the WARNING SPEED is reached or exceeded.

If there is sufficient space in the programme it may be an advantage for BEEP LENGTH, BEEP SPACING and BEEP INTERVAL to be USER DEFINABLE.

The following system of SET SPEED INDICATOR BEEPS is referred to as the COMPLEX SYSTEM and consists of combination of beeps that may be used to indicate the SET SPEED as determined by the AutoSet or the Knob position: Two short beeps 10Okph- Two long beeps Three short beeps 110kph Two long beeps one short beep Four short beeps 120kph Two long beeps two short beeps One long beep 130kph Two long beeps three short beeps One long one short beep 140kph Two long beeps four short beeps 70kph- One long two short 150kph- Three long beeps ~beeps 80kph- One long three short 160kph Three long beeps one beeps short beep 90kph One long four short OFF Four long beeps beeps Alternatively there is a SIMPLE SYSTEM which has one short beep for odd numbered speed settings and two short beeps for even numbered speed settings. A third option of NONE allows the user to switch these beeps OFF altogether if desired.

o. 5 The device should always be connected to the vehicle power supply via the ignition switch so that it is switched OFF whenever the ignition is OFF but the current settings will be retained indefinitely while the ignition is OFF and will be active as soon as the ignition is switched ON again.

Whenever the IGNITION is switched ON and the device finds it is ON and set for DRIVER it will sound ONE LONG BEEP.

Whenever the IGNITION is switched ON and the device finds it is ON and set for DRIVER it will sound TWO LONG BEEPS.

Whenever the IGNITION is switched ON and the device finds it is ON but no PARTICULAR DRIVER SETTINGS are currently activated, then the device will sound THREE LONG BEEPS.

Whenever the IGNITION is switched ON and the device finds it is OFF, then the device will sound FOUR LONG BEEPS.

I

*SS.

S.

Four long beeps will always be given when the KNOB or WARNING ALARM is first switched OFF or when the ignition is first switched ON and finds that the Knob or WARNING ALARM is set at OFF. Four long REMINDER BEEPS should then sound at 2 minute intervals whenever the device has been left at an OFF setting unless the user has set the REMINDER BEEPS to either "5 minute intervals", "10 minute intervals", or

"NEVER".

For USER DEFINABLE FUNCTIONS to be set with a single momentary push button switch, it is necessary for a routine involving 10 HOLDING IN and/or REPEATED PRESSES of the button at appropriate times to signify the required changes.

Figures 3 and 4 show how instructions may be given to the microprocessor using a single button. If the button is not released within three seconds after the Prompt Signal, then there is no change to the existing setting and the next prompt signal is activated.

CALIBRATION of the device is initiated as the final setting of the series of options shown in figure 3. For safety considerations the button can be held for as long as the driver wishes beyond the last prompt signals and it is only released when the vehicle is travelling at precisely 60kph as indicated by the vehicle speedometer. This determines the CALIBRATION CONSTANT which is then retained indefinitely or until the above calibration procedure is repeated. Although the device electronics are accurate to 4.AL r of" 4h, C,bI 40d. eI SbS c s 3 I de -fmnl accuracy of the vehicle speedometer at 6kph and the driver's ability to press the button to correspond precisely with the vehicle speedometer reading. Any error in the CALIBRATION CONSTANT at 60 kph will result in double that error at 120kph and pro rata errors at all other speeds.

The STEADY SPEED FACTOR has been set at the factory after extensive road testing. Although acceleration and deceleration rates may vary dramatically on different vehicles, a STEADY SPEED is one at which drivers are attempting to drive at a constant speed and the variations should be fairly minimal regardless of the type of vehicle or driver skills. We have 11 I~11I1 i- -ir~l- I III I I ~III 1I II I 1-1- 111 1111-11-1 n l- lll-~~i-l -ll~1 11 ~-1I-11 I lll l l-lr XI l C^ ILI l found in practice that it is very difficult to maintain a constant speed within a 2kph range but a 3kph range was fairly manageable and a 4 or 5kph range was even easier. Tests with a very sluggish vehicle showed that its NORMAL acceleration and deceleration over any four second period on flat terrain was always greater than 6.6kph. Hence MAXIMUM acceleration or deceleration will always be higher than this figure on flat terrain. More powerful vehicles can no doubt produce higher figures still, but it readily doesn't matter how much higher the acceleration and deceleration figures are so long as the SSTEADY SPEED FACTOR produces well defined and appropriate SET 10 SPEEDS and STANDBY SETTINGS. *ee.

Figure 5 shows an example of AutoSet Functions and the device responses with three different values of STEADY SPEED FACTOR Low, Medium and High. The table is typical of a worst case scenario when a vehicle is driven in traffic in a 60kph zone, then into an 80kph zone, back to 15 60kph then up to an 80kph zone again. The CURRENT SPEED is sampled at four second intervals and its value stored in Register after the value from the earlier sample has been transferred to Register The DIFFERENCE between values in and is then determined and made ABSOLUTE in before being compared with the STEADY SPEED 20 FACTOR as stored in Register The result of this comparison then determines whether the speed is "STEADY" or "NOT STEADY" and the device will then respond accordingly. The example shows the results when a vehicle's speed has to be slowly reduced then increased again due to heavy traffic in a 60kph zoned, when a driver is pushing the limit in an 80kph zone and when braking is necessary in a 60kph zone. The examples show how different STEADY SPEED FACTOR values can produce different results due to some false settings. When the value is too low, it can cause too many Le STANDBY SETTINGS, or FA$1E SPEED SETTINGS which are too high, and BENEFICIAL WARNINGS are not always given. When the value is too high, there are no BVENEFICIAL WARNINGS missed, but there are more FALSE WARNINGS given. However these are easily overcome with a single press of the button to set a MANUAL STANDBY and thereby silence the alarm. The __11 il_1_I-- 11 I ~~11 1II~ III11 I r C1__1 11 11 11- 1111llrl l^r ~~11 1-1 ~111-- 111 111~-11~ 11(1 l--ll-illl medium value gives fewer FALSE WARNINGS but could miss giving a BENEFICIAL WARNING on some occasions due to traffic conditions or driving technique.

The STEADY SPEED INTERVAL can also be varied to allow for variations in vehicle performance, driving technique and road or traffic conditions. Because the STEADY SPEED INTERVAL is selected from a continuously running clock, it can take anything from four to eight seconds for a significant change of speed to be registered when using STEADY SPEED INTERVAL of four and it can take anything from six to twelve seconds when 10 using a STEADY SPEED INTERVAL of six. By increasing the STEADY SPEED INTERVAL, a driver can make the AutoSet less sensitive to the speed changes which invariably occur at low speeds on undulating terrain or in heavy traffic conditions. This reduces the number of FALSE SPEED SETTINGS and subsequent FALSE WARNINGS but increases the chance of BENEFICIAL WARNINGS coming too late.

There are an infinite number of variations of driving circumstances and no artificial intelligence could be expected to successfully anticipate all of them. The AutoSet Model is designed to provide options and practical compromises for drivers who want to minimise the risk of speeding o. 20 infringements but don't want to be bothered with settings or knobs. The MANUAL MODE of the Auto-Set Model and the KnobSet Model provides positive settings which have no FALSE WARNINGS or MISSED WARNINGS.

Figureof the drawings is a schematic drawing of componentry for a KnobSet warning device of the present invention. The setting knob is electrically connected to a micro-controller which receives a power supply and receives signals from a Hall effect sensor or an electronic speed pulse input.

A control switch allows changes referred to in the previous figures possible.

The micro-controller can receive inputs from security devices, electrical S.J,4 co inputs, which can monitor vehicle functions and conditions, thatis the status of ignition, lights, battery and oil levels and pressures and transmit signals to the audio and/or visual warning devices such as a piezo sounder on LED and the like.

11_ 1~ 1111--11~ 1 _lll__ir 1~1 ~1 111~~~ 11-I 111 *r ~1 -~1111 The device described above provides a useful and inexpensive device or accessory for retro fitting to every car on the road.

Once the device has been correctly fitted and calibrated the driver can make all further speed settings of the device by touch and receive warnings of excessive speed by sound so there is really no need to take their eyes off the road to look at the control panel or vehicle speedometer while driving. This should enhance driving safety. The warning LED's act as visual reminders when the warning buzzer has been switched off.

The speed warning means will help drivers avoid inadvertently 10 exceeding the speed limit and the anti-theft features will help resist theft of the vehicle.

It will of course be realized that the above has been given only by way of illustrative example of the invention and that all such modifications and variations thereto as would be apparent to persons skilled in the art are S 15 deemed to fall within the board scope and ambit of the invention as is herein set forth.

Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof as defined in S. 20 the appended claims.

Claims (16)

1. A warning device for use with motor vehicles, the device including: means for sensing the speed of a vehicle on a road or support surface; means for establishing a predetermined speed, and means for issuing a warning signal, and processing means for receiving the sensed speed from the sensing means, comparing the sensed speed with the pre-determined speed, 10o and if appropriate causing the warning signal means to issue an appropriate warning signal.

2. A warning device as claimed in claim 1 wherein the warning i signal means issues an audio signal and/or a visual signal.

3. A warning device as claimed in claim 1 or claim 2 the processing 15 means is a central processing unit (CPU), eg a micro-CPU mounted on a PC board. a.

4. A warning device as claimed in any one of claims 1 to 3 wherein the warning signal means may issue a plurality or a series of warning signals ,..**including a main warning signal. 20

5. A warning device as claimed in any one of claims 1 to 4 wherein including means for setting or altering the predetermined speed.

6. A warning device as claimed in claim 5 wherein the setting means includes means for setting a basic speed setting and also means for setting a margin speed setting above the basic speed setting at which the driver can travel before the device issues a main warning signal.

7. A warning device as claimed in claim 5 or claim 6 wherein the speed setting means permits the basic speed to be set at a variety of speed increments for example 5 to 10 kph/mph.

8. A warning device as claimed in any one of claims 5 to 7 wherein the speed setting means permits the margin setting to be set at a plurality of incremental margins above the basic speed setting. I

9. A warning device as claimed in any one of claims 1 to 8 including a housing within which the processing means and the warning signals are housed and the interface is provided on the front face of the housing and comprises a keypad for entering the basic speed setting and a rotatable knob having specific positions for different settings for entering the margin speed setting.

A warning device as claimed in any one of claims 1 to 9 including theft resisting means comprising a switch in the ignition wiring which 00.0 moves between an open position preventing current flow and a closed position permitting current flow through the ignition wiring and processing means for comparing an entered code with a pre-set code and responding to o:,0 a correct match by moving the switch to the closed position; and means for entering the code into the device.

11. A warning device as claimed in claim 10 wherein the theft 15 resisting means is armed when the vehicle ignition is switched off or when a security switch is activated.

12. A warning device as claimed in claim 10 or claim 11 wherein the theft resisting means is disarmed when the security switch is switched off and a disarming code is entered into the processing means. 20

13. A warning device as claimed in any one of claims 1 to 12 wherein the device includes driver capability assessing means requiring a driver to enter an intricate data entry process before the vehicle ignition system can be enabled.

14. A warning device as claimed in any one of claims 1 to 13 including means for monitoring and issuing warnings on the condition or status of important mechanical/electrical components of the vehicle such as lighting, battery, petrol and oil levels.

A warning device as claimed in any one of claims 1 to 14 wherein adjustments to the device can be made without the need for visual determination of the current status of the device.

16. A warning device substantially as herein described with reference to the accompanying drawings. DATED this 20th day of August 1999 ALEXANDER PHILLIP CALDWELL By his Patent Attorneys CULLEN CO. 0gee S 5. S S S SSSS S 05SS 5* .5 0S S. S S. S S 0* *SbS .55. S *.55 *5 S 55