IL44146A - Method and apparatus for testing exhaust gas emission from vehicle engines - Google Patents

Abstract

1468838 Regulating IC engines LARS COLLIN CONSULT AB 11 Feb 1974 [15 Feb 1973] 06152/74 Heading F1B [Also in Division G1] Apparatus for determining certain gases, for example the carbon monoxide, hydrocarbon and nitrogen oxides content of vehicle engine exhaust gases comprises a device for operating the fuel supply system of the engine, which is to be disengaged from the transmission, in accordance with a predetermined program to cause over a fixed period of time at least one momentary increase in fuel supply sufficient to raise the speed of the engine to a speed not exceeding the maximum value, and a gas sampling unit for connecting to the engine exhaust to collect a given fraction of the exhaust gas and to determine the certain gases in the given fraction. In the apparatus shown, the throttle pedal 28 is operated as required by an electronic control unit 29 by a compressed air motor 36 which is governed by a solenoid operated valve 37 controlled by unit 29 and fed with air from bottle 40. A given fraction of the exhaust gases from exhaust pipe 27 is collected in bladder shaped bag 31 by attachment of hose 33 to one of a series of pipes 32 which are connected to exhaust gas receiver 30 and are of accurately determined length and i.d. The exhaust gas fraction collected may be led through an absorbing indicator mixture or to analyzing equipment. [GB1468838A]

Claims (4)

1. A method for determining the emission contents of the exhaust products of internal combustion engines , by directing a proportionate fraction of the exhaust products generated to a sample-receiver unit, whereby the emission products are determined, the improvement comprising the steps of A. running an internal combustion engine of a vehicle at an idling speed with the driving transmission disengaged; and B. during a fixed period of time, repeatedly subjecting the engine to a series of load variations by momentarily varying the fuel suppl to the idling engin and accelerating the engine repeatedly against its own inertia to a speed approaching but not exceeding maximum speed and immediately after an acceleration causing the engine to decelerate to the initial idling speed due to internal power losses.

2. An apparatus for determining the emission contents of the exhaust of an internal combustion of a vehicle including, in combination, a master control unit for automatically operating the fuel supply system of the engine according to a predetermined program; means for connecting to the engine exhaust system including means for dividing the exhaust into proportionat parts; and a receiver operatively connected to said means for dividing the exhaust for capturing a proportionate part of the entire exhaust during a test cycle, the improvement comprising: valve means operatively connected between said receiver and means for dividing said exhaust for controlling exhaust product flow into said receiver; the master control unit including a program selected so as to hold the engine, when out of driving relationship, at idling speed and to cause, during a fixed period of time. 44146/2 a number of fuel supply variations during which the fuel supplied does not exceed that amount which is required to raise the speed of the, engine against its own Inertial to its full speed, said program spacing the. fuel supply variations sufficiently to permit the engine to return to the idling speed due to internal engine power losses ; and means to issue a first signal at the beginning of a fixed period of time to open said valve means and means to issue a second signal at the termination of the fixed period of time to close said valve means.

3. The apparatus as claimed in Claim 2 , in which the gas proportioning means includes a chamber connectable to the engine exhaust system and comprises a plurality of equal-resistance outlets open to ambient air, and conduit means for connecting the receiver to said chamber, the receiver being so arranged that it, together with the conduit means, within the actual flow gas range, have substantially, the same resistance, as any one of the open outlets of the chamber.

4. The apparatus according to Claim 2 including a double-acting, pneumatic motor operatively connected to a fuel control pedal of the vehicle for operating the fuel supply to the internal combustion engine, a solenoid control operatively connected to the pneumatic motor for operating the same, the master control unit including electronic means for issuing signals for activating the solenoid control according to the program of the roaster control unit.