GB2281784A

GB2281784A - Misfire detector for catalytic converter protection

Info

Publication number: GB2281784A
Application number: GB9415827A
Authority: GB
Inventors: William Michael Bowery
Original assignee: Individual
Current assignee: Individual
Priority date: 1993-08-05
Filing date: 1994-08-05
Publication date: 1995-03-15
Also published as: GB9316236D0; GB9415827D0

Abstract

A simply installed warning device is disclosed, allowing drivers of petrol driven vehicles incorporating a catalytic convertor some advanced warning of its destruction if unburnt petrol is driven into it owing to spark plug failure in one or more cylinders. The device is a monitoring device only and therefore requires no interference with existing ignition controls. The device will fit all makes of vehicle and can be transferred from one vehicle to another when required. The device comprises clamps fitted to each plug lead to detect the spark voltage and a further lead connected to the distributor HT lead. A modification has the latter connection replaced by a sensor for the LT signal to the distributor. Mismatch between the plug signals and the distributor signal visibly or audibly signals a misfire to the driver.

Description

CT. Guard - CatalYtic Convertor Protection DAHP-ESS/SNOWXWET 20ADSsFLOODING,FAULTY PLUGS or LEADS all can mean trouble for vourcatalYtic convertor.

This is a simply installed Hi-tech monitoring device that protects your catalYtic convertor from 'burning out' distruction if a plug fails to fire.

The unit can easily be installed to your vehicle as no drilling or cutting of wires is required, it also can be removed and transferred to another vehicle if required, Installation time 10-15 mins.

WHAT IT DOES.

The sensor will detect a failure to 'spark' at the plugs. If 3 plug lead becomes detached/wet or broken, or a plug becomes 'fouled' or fails. then the catalYtic convertor is in danger from unburnt fuel being driven through the engine and this causes rapid internal distruction of tne catalYtic convertor. The units resulting failure will become aDoarent on MOT tests using gas analysis equipment, this will require replacement of unit, costing several hundred pounds, dependent on type of vehicle.

This device will provide a dashboard audioZvisual alarm with a constant green light showing it is in operation and a red light and buzzer if a proolem occurs. If the alarm is activated then we recommend that you pull over to stop ASAP, and then switch off the engine, (most car manufacturers require immediate shut down of engine if misfiring). If no obvious signs of problem such as plug leads detached or wet etc. are visible, then seek assistance. A test button is also on the display panel to check the systems circuits, this can be pressed for a short time to check alarm and red light are operating okay, then release the button. (Test wnile engine is ticking over in neutral gear).

HOW IT WORKS. (Technical).

The sensor detects low voltage signals passed from your distributor to the coil and 'matches' them precisely to the high voltage signals to your plugs on an individual basis. Any discrepancy in this matching will activate the audio/visual alarm. The system has a short delay of approximately 10 seconds when starting up before operating.

The unit in no way effects the running or performance of the engine and is not a 'tuning' aid. No interference to your existing electricai system occurs. The unit is a monitoring device only.

CAT GUARD - CATALYTIC CONVERTOR PROTECTION DEVICE. TECHNICAL INFORMATION Method 1 The sensor unit is positioned in the engine bay close to the distributor, the leads provided are clipped around each H.T. lead on route to the plugs using the clamp attached. No actual direct connection is necessary as the unit is a monitoring device. A further lead is attached using the same method, to the HT lead from the coil to the distributor.

All that remains is to connect the live 12v+ wire and an earth 12v- and connect the jack plug from the dashboard display unit.

Method 2 Performs the same function as Method 1. It is connected using the same method to the H.T. Plug leads. (No connection to HT to coil.) The live from switch 12v and low tension signal to the distributor are picked up from a traditional coil system. The required adaptors (provided) are to give two connections to the existing 'Pins' on the coil. An earth is the final connection.

NOTE: It is Probable that Method 1 will be preffered as it suits all types of ignition systems and does not require any identification of individual wires on more complex car ignition systems The sensor uses on 8BIT micro controller/processor programmed to carry out additional functions for car fleet operators. That is in addition to the primary function of misfire detection.

A. Heat Detection - inclusion of a Bi-Metal heat sensing clamp connected to the catalyser body, will provide warning of excessive overheating due to prolonged high speed or towing overloads etc.

B. SHOCK Detection - simple shock detector clamped (as above) to provide warning of possible cataylist damage from rough terrain etc/abuse.

Items A & B are relayed to the driver via the dashboard display also, and are counted and stored in the sensing unit which can be 'downloaded' to the fleet car owner as to the number of warnings issued in a given period if required.

The interior dashboard display unit remains the same in all variants, it consists of a small unit similar to a cigarette packet in size with a display of a greenlight for unit operating OK. Red light + Buzzer for warning, A small circuit test button (optional). The display unit is supplied with a fixed wire to be connected to Sensor using the jack Plug attached.

The system can be provided up to 12 cylinder Cars.

Claims

CAT GUARD - CATALYTIC CONVERTOR PROTECTION CLAIMS

The catalytic convertor devive is universal to all types and makes of petrol driven vehicles which incorporate a catalytic convertor.

The unit is designed to be easily installed without specialist knowledge by DIY if required.

The device requires no interference with the vehicle existing ignition systems control.

The device gives the vehicles owner an audio/visual warning of spark failure which would result in unburnt fuel deing driven into the catalyser which will cause rapid destruction of internal components.

In addition to the primary function as above I have incorporated the ability to add on further protection, for fleet car users and hire car operators, These are impact/shock detection to 'count' the number of warinings issued to the driver and be able to 'download' this information to the owner as required.

All the variants described are able to be transferred to another vehicle easily and only require the same number of cylinders to be compatible.