SU1180727A1 - Device for measuring cyclic feed of fuel into internal combustion engine - Google Patents

Abstract

DEVICE / NECK MEASUREMENT OF CYCLE SUPPLY OF POWERING INTO THE INTERNAL COMBUSTION ENGINE, containing sequentially connected fuel pressure sensor, amplifier and measuring device, characterized in that, in order to improve accuracy, the device is equipped with a variable delay circuit, a peak detector, a matching circuit, an integrator, a circuit, a integrator, and a integrator. a switch, wherein the amplifier output is connected in parallel to the first input of the coincidence circuit, to the first input of the variable delay circuit and to the input of the peak detector, the output of the AC circuit This delay is connected to the second input of the coincidence circuit, the output of which is co-. The second input of the variable closing circuit is connected via a switch to the midpoint of the potentiometer, and the peak 9 detector is connected to the measuring device via a switch to the midpoint of the potentiometer.

Description

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PHIL, 1

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The invention relates to the diagnosis of internal combustion engines and can be used in monitoring the technical condition of heat-injection equipment of diesel engines.

The aim of the invention is to improve the accuracy of measuring the cycle fuel supply by introducing an integration of the change in fuel pressure during the injection period and directly fixing the result in the measuring instrument.

The device makes it possible to reduce the laboriousness of the control due to the elimination of computational operations and to simplify the applicable measuring equipment.

FIG. 1 is a block diagram of a device for measuring a feed cycle; in fig. 2 - voltage diagrams for the operation of the device.

The device contains series-connected fuel pressure sensor 1, amplifier 2 and measuring device 3. The device also includes a variable delay circuit 4, a peak detector 5, a coincidence circuit 6, an integrator 7, a potentiometer 8 and a switch 9. The output of amplifier 2 is connected in parallel to the first input of the matching circuit 6, to the first input of the variable delay circuit 4 and the input of the peak detector 5. The output of the variable delay circuit 4 is connected to the second input of the matching circuit 6, the output of which is connected in the measurement mode via The grator 7 and the switch 9 with the measuring device 3. The second input of the variable delay circuit 4, which serves as the control input, is connected to the measuring point via the switch 9 with the midpoint of the potentiometer 8, and the peak detector 5 to its output through the switch 9 is connected to the measuring mode device 3, which is simultaneously connected via switch 9 with the midpoint of potentiometer 8.

The device works as follows.

The signal U (t) from the fuel pressure sensor 1 (Fig. 1) connected at the nozzle of a controlled injector (not shown) is amplified by amplifier 2 and is fed to the first input of circuit 6

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match and the first input of the variable delay circuit 4, start it, and the input of the peak detector 5. The variable delay circuit 4 generates a pulse whose duration t (Fig. 2) is proportional to the control voltage U, which in the position of the switch 9 is measured from the midpoint potentiometer 8. The signal and variable delay circuits 4 are fed to the second input of coincidence circuit 6, which is locked for this time and cuts out of the signal K U (t) a part of duration t ,, corresponding to the delay of the start of fuel injection. The rest of the signal U (t) is fed to the input of the integrator 7, which integrates it, is averaged over the time of incoming pulses, and the level of the output signal of the integrator 7 is proportional to the area of the pressure signal. All other things being equal, the opening time of the nozzle is determined by the tightening of the nozzle spring and the mass of its moving parts, and at idle the maximum fuel injection pressure is approximately equal to the nozzle opening pressure;

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The pressure is generated at the output of the peak detector 5 and in the Monitoring mode is connected to one pole of the measuring device 3, the OTHER pole of which is connected to the midpoint of the potentiometer 8. The position of the potentiometer 8 is adjusted so that the measuring device 3 is set to the zero position. In the Measurement mode, the set voltage is connected to the second input (control) of the variable delay circuit 4. Then the duration tj will be equal to t3, where K-, is the proportionality coefficient. Since U.

then t,

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«- Ko Rd | miksh. Ie delay time t, is determined by the nozzle opening pressure. When calibrating the device, select the resistance of the potentiometer 8 so that t is equal to the actual moment. the beginning of the injection by the nozzle, and the area of the S- area (Fig. 2) is blocked until the moment of the beginning of the injection of fuel and does not pass into the measuring channel.

K U (t}

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Claims (1)

DEVICE FOR MEASURING CYCLE FUEL SUPPLY TO THE INTERNAL COMBUSTION ENGINE, containing a fuel pressure sensor, an amplifier and a measuring device connected in series, characterized in that, in order to increase accuracy, the device is equipped with a variable delay circuit, a peak detector, a matching circuit, an integrator, and a potentiometer a switch, and the amplifier output is connected in parallel to the first input of the matching circuit, to the first input of the variable delay circuit and the input of the peak detector, the output of the variable circuit the delay is connected to the second input of the matching circuit, the output of which is co-. is dined through an integrator and a switch with a measuring device, the second input of the variable delay circuit is connected via a switch to the midpoint of the potentiometer, and the peak detector is connected through its switch through an output to the measuring device, which is simultaneously connected through the switch to the midpoint of the potentiometer. 118372.7