SU1564373A1 - Device for determining parameters of fuel spraying process by atomizer of diesel engine - Google Patents

Abstract

The invention relates to engine-building, can be used for testing fuel-injection equipment of diesel engines, and allows you to extend the functionality. The device contains a jet pressure sensor 3 mounted on an elastic element 2 in the chamber opposite the spray nozzles of the nozzle 5, as well as a measuring complex containing sensor 3, amplifier 6, mode switches, low 11 and high 7 frequency filters, amplitude 8 and peak 12 detectors , comparator 9, driver 10, analog-to-digital converter 13, digital processing device 14 with an indicator 15. The device has three modes of operation implemented using switches 16 and 17, which allows determining the quality of pylivani fuel needle mobility spray nozzles and throughput capacity. 1 sec. f-ly, 1 ill.

Description

can be determined using the switches 16 and 17, which makes it possible to determine the quality of sawing fuel, the mobility of the needle of the sprayer and the throughput of the nozzle. 1 sec. f-ly, 1 ill.

The invention relates to engine-building and can be used for testing fuel-injecting equipment.

The purpose of the invention is to expand the functionality of the device in determining the parameters of the injection nozzle process.

The drawing shows a schematic block diagram of a device for determining the parameters of a nozzle injection process.

The device comprises a housing 1 in which an elastic element 2 is fixed with a jet pressure sensor 3 and a 4 fuel jets catcher located opposite the spraying rejects of the tested nozzle 5, which is fixed to the housing 1. The 4 jets of fuel fuel catcher is installed 5 nozzle tip nozzle 5. In addition, the device contains an amplifier 6, the input of which is connected to the output of the sensor 3, and the output is connected with a series-connected high-frequency filter 7, an amplitude detector 8, a comparator 9 and form 10, made in the form of a standby multivibrator. The output of amplifier 6 is also connected to a low-pass filter 11 in series, a peak detector 12, an analog-to-digital converter (A1SCH) 13, and an input to a digital processing device 14 (DSP), the output of which is connected to an indicator 15.

A three-section switch 16 connects the output of amplifier 6 to the inputs of filters 7 and 11, and the input of peak detector 12 to the output of amplitude detector 8 or the output of filter 11 of low frequencies. A two-way switch 17 connects the output of the comparator 9 to the control input A1SCH 13 directly or through the driver 10. The output of the comparator 9 is also connected to the control input of the central monitoring station 14, and the control output AID 13 is connected to the pack

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equal input of the peak detector 12.

The device determines the quality of fuel spraying, the mobility of the nozzle atomizer needle under the crushing injection mode, and the nozzle capacity when pumping the test nozzle from the bench section of the high pressure fuel pump (not shown).

The device has three modes of operation.

In the first mode, when determining the quality of fuel spraying, the output of sensor 3 is connected in series through amplifier 6, switch 16, high-frequency filter 7, amplitude detector 8, peak detector 12. ASH1 13 and UCO 14 and indicator 15. In addition, the output of amplitude detector 8 is consecutive connected via a comparator 9, a switch 17 and a standby multivibrator 10 to the control input of the analog-digital converter 13. i

When fuel is supplied from a control pump (not shown) through the tested jet nozzle 5, the fuel jets act on the fuel jets catcher 4, the displacement of which through the elastic element 2 is transmitted to the sensing element Hbtfi of the sensor 3, the signal of which passes through the amplifier 6, high-frequency filter 7 The spectral components distinguishing themselves due to the cutting of fuel jets are fed to the input of the amplitude detector 8, the output of which is a signal whose amplitude characterizes the quality of atomization of the fuel. Peak detector 12, which receives this signal at its input, operates in discrete mode, i.e. remembers the maximum amplitude of the signal at the time of its measurement by the ADC 13, followed by resetting itself. The signal from the output of the A / D converter 13 is fed to the DSCO 14, which sums and averages the amplitudes of the signals over a given number of cycles N by the formula ACJ,

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ZA m and gives the measurement result

signal amplitudes on a digital indicator 15.

In order to perform the above operations from cycle to cycle during the cycling of the nozzle, the synchronization circuit works in parallel, containing a comparator 9 and a waiting multi-vibrator 10, which cut off the signal from the A1SCh 13, after measuring the amplitude of the A1SC signal during a single fuel injection, the peak readings are reset detector 12 from controlled output ASChT13

Introduction to the standby multivibrator 10 is due to the fact that when determining the quality of fuel spraying under the mode of spraying fuel injection, the signal at the comparator output in the process of single injection consists of a burst of pulses formed as a result of oscillatory movement of the dispensing needle of the atomizer nozzle. While waiting, the multivibrator 10 generates a rectangular pulse, the front of which corresponds to the start of injection along the front of the signal of the comparator 9, and the slice of the rectangular pulse has a constant delay time sufficient for the end of the injection process and A1C1 13 is triggered by the cut of this pulse for one injection, measure the maximum amplitude of the signal at the output of the peak detector 12.

In the second mode, when determining the needle mobility of the nozzle atomizer on the crushing injection mode, the device works in the same way as in the first mode, with the difference that the indicator 15 displays information on the total number of jumps To the needle of the atomizer during N fuel injections, which is achieved by setting the switch 17 to the position in which the input of the ADC 13 is connected directly with the comparator 9.

During the oscillatory motion of the needle of the nozzle 5, separate jets of fuel are formed, which are detected by the jet pressure sensor 3, the signal from which the amplitude detector 8 passing through the high-frequency filter 7 converts the comparator 9 into a pack of rectangular pulses that enter the input

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UCO 14, where the number of pulses K is calculated for N fuel injections.

The mobility of the nozzle needle is determined by the complex parameter, equal to the product of the average signal amplitude selected by the high-frequency filter 7 and the number of jumps of the needle needle.

In the third mode, when determining the throughput of the nozzle, the signal from sensor 3 through amplifier 6, switch 16 and low-pass filter 11 is fed to the input of peak detector 12, the output signal of which is processed by the circuit, similarly to the pre-next modes. The difference compared with the previous modes is the selection of the sensor signal in the low-frequency region and the start control of the A1SC 13 through the switch 17 directly from the cut-off signal of the comparator 9, taking into account that the nozzle capacity is determined at the frequencies of rotation of the control pump shaft, providing a single needle single fuel injection time. The front and cut of the comparator signal corresponds to the start and end of the injection. The result of measuring the maximum amplitude of the signal for a given number of cycles N is displayed on the indicator 15.

The jet pressure sensor can be designed as a piezo accelerometer.

OCC 14 allows the following operations:

- sum the magnitudes of the amplitudes of the signals for a given number of cycles;

- averaging the amplitude of the signal A; for a given number of cycles)

- count the number of pulses received from the comparator for a given number of cycles.

In the crushing injection mode of the nozzle when starting the analog-digital converter from the waiting multivibrator K 5 N. KN, if the spray needle rises once per injection.

Claims (1)

The error of the device in determining the bandwidth by the magnitude of the signal amplitude in the low-frequency region is 1% compared with time meters. Invention Formula A device for determining parameters of a fuel injection process by a diesel engine injector containing A housing with a chamber, an elastic element mounted along the perimeter in the chamber, an injector mounted in the housing with nozzle holes directed toward the elastic element, on the other side of which a jet pressure sensor is installed, made in the form of a piezoaccelerometer, and measuring a unit having a series-connected amplifier, a high and low frequency filter, and an indicator, the amplifier input being connected to the output of the jet pressure sensor, and the elastic element is designed with a half-period of natural oscillations greater than flax possible duration of injection, characterized in that, to improve the neither the functionality, the device is provided with an amplitude detector, the input of which is connected to the output of the high-pass filter, a comparator, the input of which is connected to the output of the amplitude detector, and a series-connected peak detector, an analog-to-digital converter, the control output of which is connected to the control input a peak detector, a digital processing device, whose control input is connected to the comparator output, Editor A.L. Compiled by L.Petrov Tehred L.Sfdyukova Order 1148 Tyr g 439 VPIISH1 of the State Committee on and i gains and Kpi i pi--, at 1: 111 (, (.. 113035, Moscow, F, Z, Raushsk nag.,; I. / S 0 five 0 five 0 738 and an indicator, as well as a three-section switch, the input of the third section of which is connected to the input of the peak detector, a two-section switch, the input of the second section of which is connected to the control input of the analog-digital converter and a pulse shaper in the form of a waiting multivibrator, the input of which is connected to the second output the first section of the on-off switch, the second output of the second section of which is connected to the output of the pulse former, the input of the first section of the on-off switch The first output of the first section is connected to the first output of the second section, the output of the amplifier is connected to the inputs of the first and second sections of the three-position switch, the second output of the first section of which is connected to the input of the high-pass filter, and the first output of the second section to the input of the filter low frequencies, the output of which is connected with the first output of the third section of the three-part unclamped unit, the second output of the third section of which is connected with the output of the detector, and the first output of the first session with the filter input see t h. Koppi-ktor l l h i. : k l l h Subscription