RU124801U1 - DEVICE FOR DIAGNOSIS OF DEVICES OF POWER SYSTEM, ELECTRIC START-UP, INFORMATION-MEASURING SYSTEM OF DIESEL - Google Patents

Abstract

A device for diagnosing devices of the power system, electric start-up, information and measuring system of a diesel engine containing a stand base on which the tested high pressure fuel pump (TNVD), nozzles, graduated cylinders, a fuel distributor, upper and lower fuel tanks, a booster booster pump, a fuel filter, a pressure gauge damper, a pressure gauge, a fuel cylinder through which high pressure fuel lines (HPT) pass, and the fuel cylinder is connected to a high pressure battery Ia fuel and hydraulic oscillation damper with a fuel in the cylinder, and the shaft is placed the test disc pump mounted with a permanent magnet valve opening control hydraulic oscillation damper fuel and the permanent magnet timer top dead center (TDC) of the first cylinder; an electric circuit for detecting changes in fuel pressure in a fuel engine containing a fuel pressure sensor located in the fuel cylinder and connected by a switch and electric circuits to a current amplifier, analog-to-digital converter (ADC), a port and a computer, the computer being connected to the display; an electric circuit of the TDC marker of the first cylinder, comprising an electric coil located on the high pressure fuel pump housing and connected through an electric circuit to an electric unit; an electric control circuit for the spool of the fuel cylinder with a damper for hydraulic vibrations of fuel, consisting of an electric coil mounted on the injection pump housing, a direct current amplifier and an electric coil of the spool of the fuel cylinder with a damper

Description

The utility model relates to devices for measuring parameters of a power system, an electric start-up system, an information-measuring system of a diesel engine and can be used to diagnose fuel equipment, a tachometer, a starter, and a starter circuit.

A device for diagnosing diesel systems is known (patent for the invention of the Russian Federation No. 2370745 IPC G01M 15/04 dated 10/20/2009) [1-3] containing the base of the stand on which the tested high-pressure fuel pump (TNVD), nozzles, measured cylinders, a fuel distributor, upper and lower fuel tanks, a booster booster pump, a fuel filter, a pressure gauge damper, a pressure gauge, a fuel cylinder through which high pressure fuel lines (HPT) pass, moreover, the fuel cylinder is connected to the high pressure fuel accumulator and to the gas an hydraulic fluid vibration oscillator in the cylinder, and a disk with a permanent magnet for controlling the opening of the hydraulic vibration damper spool and a permanent top dead center marker (TDC) of the first cylinder is mounted on the shaft of the test pump; an electric circuit for detecting changes in fuel pressure in a fuel engine containing a fuel pressure sensor located in the fuel cylinder and connected by a switch and electric circuits to a current amplifier, analog-to-digital converter (ADC), a port and a computer, the computer being connected to the display; an electric circuit of the TDC marker of the first cylinder, comprising an electric coil located on the high pressure fuel pump housing and connected through an electric circuit to an electric unit; an electric control circuit for the spool of the fuel cylinder with a damper for hydraulic vibrations of the fuel, consisting of an electric coil mounted on the injection pump housing, a direct current amplifier and an electric coil for the spool of the fuel cylinder with a damper for hydraulic vibrations of the fuel, interconnected by an electric circuit, a DC voltmeter connected parallel to the vehicle’s battery and an ammeter with a current sensor mounted on a wire connecting the positive terminal One battery with a starter and its clamps clasping it, fixed on the stand base.

The disadvantage of this device is the small number of diagnosed parameters of the diesel engine, affecting its performance.

The technical result is aimed at expanding the number of diagnosed diesel parameters.

The technical result is achieved by the fact that in a device for diagnosing diesel systems containing a stand base on which the tested high pressure fuel pump is located, nozzles, graduated cylinders, a fuel distributor, upper and lower fuel tanks, a booster pump, fuel filter, pressure gauge damper, pressure gauge, fuel a cylinder through which the high pressure fuel pump passes, moreover, the fuel cylinder is connected to a high-pressure fuel accumulator and to a damper for hydraulic oscillations of the fuel in the cylinder, and is located on the shaft of the test pump claim mounted with a permanent magnet valve opening control damper hydraulic fuel oscillations and the permanent magnet timer TDC of the first cylinder; an electric circuit for detecting changes in fuel pressure in a fuel engine containing a fuel pressure sensor located in the fuel cylinder and connected by a switch and electric circuits to a current amplifier, ADC, port, and computer, the computer being connected to the display; an electric circuit of the TDC marker of the first cylinder, comprising an electric coil located on the high pressure fuel pump housing and connected through an electric circuit to an electric unit; an electric control circuit for the spool of the fuel cylinder with a damper for hydraulic vibrations of the fuel, consisting of an electric coil mounted on the injection pump housing, a direct current amplifier and an electric coil for the spool of the fuel cylinder with a damper for hydraulic vibrations of the fuel, interconnected by an electric circuit, a DC voltmeter connected parallel to the vehicle’s battery and an ammeter with a current sensor mounted on a wire connecting the positive terminal One battery with a starter and clasping it with its own clamps, an additional unit for diagnosing tachometers is installed, mounted on the base of the stand, consisting of a logic element "I", a differentiating circuit with a diode at the output, a resistor connected to the output of the logic element, multivibrator, working in self-oscillating mode, a summing electronic counter, light emitting diodes.

Comparative analysis with the prototype shows that the proposed device is distinguished by the introduction of additional elements into it and the scheme of their connection to the vehicle’s information-measuring system, namely: a unit for diagnosing tachometers, consisting of a logical element "I", a differentiating circuit with an output diode, a resistor , its findings connected to the output of a logical element, a multivibrator operating in self-oscillating mode, a summing electronic counter, light emitting diodes, which is fixed ene based on the stand and connected to a tachometer diagnosed.

The introduction of these elements allows you to further control the performance of the tachometer, which extends the number of diagnosed parameters and allows us to conclude that the claimed device meets the criterion: "Significant differences".

The device is illustrated by drawings:

figure 1 and 2 presents a device for diagnosing devices of the power system, electric start, informational-measuring system of a diesel engine, figure 3 - current-voltage characteristic of the battery, figure 4 is a diagram of the change in fuel pressure in the theater depending on the angle of rotation of the camshaft .

A device for diagnosing devices of a power system, electric start-up, information and measuring system of a diesel engine contains a stand base 1 (FIG. 1), on which the tested high-pressure fuel pump 2, nozzles 3, graduated cylinders 4, fuel distributor 5, upper 6 and lower 7 fuel tanks are placed, a booster pump 8, a fuel filter 9, a pressure gauge damper 10, a pressure gauge 11, a fuel cylinder 12 through which the theater 13 pass, is connected by a pipe 14 to a fuel high pressure accumulator 15, and a pipe 16 to a hydraulic vibration damper fuel 17 in the cylinder 12. The damper of hydraulic vibrations of the fuel 17 is made in the form of a ball connected by a pipe 16 to the fuel cylinder 12 through an opening 18 made in the spool 19, which is designed to communicate the damper of hydraulic vibrations 17 with the fuel cylinder 12 at intervals between feeds fuel in separate sections of the high-pressure fuel pump 2. The return spring 21 is placed above the spool 19 in its housing 20, an electric coil 22 is installed over the other part of the spool 19, forming a solenoid. The electric coil 22 of the solenoid is connected by electric lines 23 and 24 through a DC amplifier 25 to an electric coil 26 mounted on the front of the injection pump 2. At the front end of the cam shaft 27 of the injection pump 2, a movable disk 28 is mounted together with a permanent magnet 29 mounted on it, consisting of four permanent magnets placed in relation to each other at a certain angle. A fuel pressure strain gauge 30 located in the fuel cylinder is connected by a switch 41 and electric circuits 31, 32, 33 and 34 to a current amplifier 35, an ADC 36, a port 37, a computer 38 and a display 39. The TDC sensor of the first cylinder containing an electric coil is connected electrical circuits 40, 32, 33 and 34 with an electrical unit consisting of an ADC 36, port 37, computer 38 and display 39. All electrical circuits are switched on using switches 41, 58, 59. A DC 56 voltmeter connected in parallel with the battery car batteries For 43 and an ammeter 44 with a current sensor 45 mounted on a wire connecting the positive terminal of the battery 43 to the starter 46 and wrapping it around its clamps, a tachometer diagnostic unit 47, mounted on the base of stand 1, consisting of an AND gate 50, a differentiating circuit 48 with a diode 49 at the output, a resistor 51, connected to the output of the logic element “I” 50, connected to the diagnosed tachometer 55, a multivibrator 54 operating in a self-oscillating mode, summing the electronic count Chica 53, light emitting diodes 52 (FIG. 2).

The fuel high-pressure accumulator 15 is designed to maintain an excess fuel pressure of 150 MPa in the fuel cylinder 12. This amount of excess pressure eliminates both erosive destruction of the outer surfaces of the theater 13 due to the elimination of the occurrence of cavitation, and to increase the response speed of the electric circuit for registering pressure in the theater.

For a four-cylinder four-stroke diesel engine, the angles φ ₁ , φ ₂ , φ ₃ , φ ₄ between the permanent magnets 29 are 20 ° of the camshaft rotation, since it is known that the duration of the full supply of diesel engines does not exceed 40 ° of the crankshaft rotation or 20 ° of the camshaft rotation. Angles φ ₅ , φ ₆ , φ ₇ , φ ₈ are 70 ° of the camshaft. This value corresponds to the rotation angles of the camshaft of the injection pump 2 in the intervals between the fuel supply to the nozzles 3 by separate sections of the injection pump 2.

The presence in the device of a summing electronic counter 53, connected to the output of the logic element “I” 50, light-emitting diodes 52, a differentiating circuit 48 with a diode 49 at the output, allows the counter 53 to be “reset”, counted, and converted into short pulses at its output "from a multivibrator 54 operating in self-oscillating mode for a time equal to the duration of the pulses coming from the diagnosed tachometer 55, as well as read and register the code at the output of the summing electronic counter 53, compare it with normative and decide on the technical condition of the diagnosed tachometer 55.

The device for diagnosing devices of the power supply system, electric start-up, information-measuring system of the diesel engine operates in two modes: in the first mode, the electric start-up system is diagnosed, in the second mode, the fuel equipment and tachometer are diagnosed.

In the first mode of operation, when the direct gear in the gearbox is engaged, the engine is braked by the parking and service brakes. Special stops are placed under the wheels of the car. When connecting the device, the voltmeter 42 shows the EMF of the battery 43 (E _b ). Turning on the switch of devices and the car’s starter and starting the diesel engine through the starter 46, the full braking current I _pt flows, which is recorded by ammeter 44, the voltmeter 56 in this case shows the voltage on the starter (U _st ). According to the results obtained, the maximum electromagnetic power of the starter P _elm , the total resistance of the circuit R _{article are estimated} , and the current-voltage characteristic of the battery is built at two points (Fig. 3), which allows you to determine the short-circuit current I _{kz of the} battery 43 and its internal resistance R _b .

Calculations are carried out according to the formulas:

Based on the results obtained, a conclusion is made about the technical condition of the starter and starter circuit.

In the second mode of operation, the engine is released and fuel is supplied to the high-pressure fuel pump 2 from the lower fuel tank 7 through the fuel distributor 5 and the fuel filter 9 using the fuel pump 8. The high-pressure fuel pump 2 delivers fuel to the nozzles 3 under high pressure through the high-pressure fuel pump 13.

To diagnose the technical condition of the high pressure fuel pump 2, nozzles 3 and high pressure fuel pump 13, it is necessary to close the contacts of the switches 41, 58.59, respectively. In this case, the electric control circuits of the control valve of the fuel cylinder 12 with the damper of hydraulic vibrations of the fuel 17, registration of changes in fuel pressure in the theater 13 and the TDC of the first cylinder will work.

The electrical control circuit for the control valve of the fuel cylinder 12 with the damper of hydraulic vibrations of the fuel 17 operates as follows: when the fuel flows through the theater 13 with a variable pressure, they are subject to vibrations that are transmitted to the fuel in the fuel cylinder 12. Under the influence of vibrations of the theater 13 the wave phenomena that adversely affect the operation of the fuel pressure sensor 30. This is due to the occurrence of resonance during the addition of oscillations caused by vibrations of the fuel assembly 13, according to which th fuel is supplied to the injectors.

When the movable disk 28 is rotated by an angle of 45 °, the permanent magnet 29 moves at the turns of the electric coil 26, in which an electric current occurs. The electric current through the electric circuits 24 and 23 through the current amplifier enters the electric coil 22. Under the influence of the electric field arising in the coil 22, the spool 19 moves to the left, compressing the return spring 21. In this case, the hole 18 in the spool 19 is aligned with the hole of the pipe 16. In this case, part of the fuel from the fuel cylinder 12 will flow into the ball 17, in which there is air. Due to the periodic compression of the air in the ball 17, the wave oscillations in the cylinder 12 are rapidly damped. When the cam shaft is rotated through the angles φ ₁ , φ ₃ , φ ₄ and φ ₂ , fuel is supplied to the first, third, second, and fourth sections of the high-pressure fuel pump 2 and to the first , third, second and fourth nozzles, respectively. However, the damper 17 does not work. At time intervals corresponding to the angles φ ₅ , φ ₆ , φ ₇ and φ ₈ , the ball 17 through the hole 18 in the spool 19 communicates with the fuel cylinder 12, in which the hydraulic oscillations in the fuel are damped.

Thus, the damping of wave phenomena arising in the fuel cylinder 12 due to vibrations of the fuel assembly 13 occurs in the time intervals between the fuel supply of the injection pump 2 to the nozzles 3.

The principle of operation of the electrical circuit for detecting changes in fuel pressure in the fuel assembly 13 is that the pressure change is recorded by the fuel pressure sensor 30, the electrical signal supplied to the sensor 30 is amplified by a current amplifier 35 and fed to the ADC 36, which converts the analog signal to its corresponding code . This code through port 37 enters the computer 38, the output of which is connected to the display 39, which displays information about the change in fuel pressure in the theater 13.

When the camshaft 27 of the injection pump 2 rotates, the fuel is pumped in sections under high pressure in the order of the diesel cylinders through the theater 13 to the nozzles 3. When the fuel flows through the section of the theater 13 located in the fuel cylinder 12, the fuel pressure pulse is transmitted through the walls of the theater 13 and fuel, being under pressure of 150 MPa in the fuel cylinder 12, to the pressure sensor 30, from which the electric signal is supplied through the electric circuit 31 to the current amplifier 35 and ADC 36. The accuracy of the registration of the fuel supply process is determined by the amplitude-frequency and the characteristics of measuring instruments, by which is generally understood transformation ratio signal dependent on the frequency. The idea of the necessary frequency spectrum describing the processes in the fuel equipment with a given accuracy can be obtained on the basis of triangular and rectangular pulses, the shape of which is close to the oscillograms of the processes studied in the fuel equipment (for example, the curve of the change in fuel injection pressure depending on the angle of rotation of the cam shaft Injection pump 2).

The limits of the necessary spectrum can be established by the example of the analysis of a triangular impulse described by a function in the form of a series:

where A ₀ is the value of the input signal;

a is the wavelength of the input signal;

k is the order of the considered harmonic.

When registering the fuel supply process with steep fronts, the necessary spectrum can be determined by the magnitude of the phase shift caused by the fact that the amplitude of the transmission pulse does not reach the nominal value immediately, but after some period φ _n , which is usually called the rise time.

The largest increase in the fuel supply front is observed for pulses approaching rectangular in shape, and are described by the following expression in the form of a series:

The signal from the ADC 36 is supplied through electric circuits 32, 33 and 34 to port 37, computer 38 and to the display 39 as a graphical representation of the change in fuel pressure in the fuel assembly 13 from the angle of rotation of the camshaft of the injection pump 2 (Fig. 4).

In the case of fuel supply by the first section of the high-pressure fuel pump 2, the electric circuit of the TDC marker of the first cylinder is triggered, since when the permanent magnet 57 moves near the electric coil 42, a magnetic flux Φ occurs in the gap between these parts, and at some point in time t it reaches a maximum, and then decreases. In accordance with the change in the magnetic flux, the magnitude of the emf created in the coil 42, determined by the formula, also changes;

, между которыми кривая ЭДС проходит через ВМТ. Электрический импульс от электрической катушки 42 передается по электрическим цепям 40, 32, 33 и 34 на дисплей 39 в виде импульса 8 (фиг.4).In accordance with expression (4), the EMF reaches its maximum value at maximum

between which the EMF curve passes through the TDC. The electric pulse from the electric coil 42 is transmitted through electric circuits 40, 32, 33 and 34 to the display 39 in the form of a pulse 8 (figure 4).

On the diagram of the change in pressure of fuel injection into the engine cylinders, depending on the angle of rotation of the camshaft (Fig. 4), point 1 corresponds to the beginning of the increase in pressure coinciding with the rise of the discharge valve. At point 2, the fuel pressure reaches a value at which the torque of the nozzle spring is overcome, the needle breaks away from its seat, and injection occurs. In section 3-4, there is a decrease in the rate of increase in injection pressure due to an increase in the volume in the atomizer when the nozzle needle is raised. At point 5, the injection pressure reaches its maximum value. Point 6 corresponds to the moment the nozzle needle fits into the saddle, and at point 7 the pressure valve fits into the saddle.

The diagram shows, as an example, measurements of fuel injection into cylinders in one working cycle of a four-stroke four-cylinder diesel engine. These diagrams can be compared with reference design diagrams and determine malfunctions in the operation of the injection pump sections and nozzles both on the stand and on the engine mounted on the stand or on the vehicle. For example, Fig. 4 shows that the injection pump section of the third cylinder has low pressures at points 1 and 7, which indicates a loose fit of the discharge valve in the seat and wear of the plunger pair. The section of the fourth cylinder has an insufficient tightening of the nozzle needle spring, which therefore rises earlier. The pressure at point 5 of this section does not reach the maximum value. This will lead to a deterioration in atomization of the fuel in the combustion chamber and to a deterioration in the flow of the combustion process.

The volume of fuel injected by the nozzles 3 (figure 1) is determined using graduated cylinders 4.

To diagnose the information-measuring system in the second mode, the diagnosed tachometer 55 is connected to the unit for diagnosing tachometers 47, the engine is started. As a result, a voltage pulse from the diagnosed tachometer 55 is fed to the input of the logical element "And" 50 and to the input of the differentiating circuit 48 with the diode 49 at the output. At the output of the differentiating circuit 48, a pulse will be generated, which will be fed to the zero setting input of the summing electronic counter 53, and the counter will be reset to zero, and short pulses will be transmitted to the output of the And element 50 only for a time equal to the pulse duration from the diagnosed tachometer 55. The pulses are counted the summing electronic counter 53 and are converted into a code, each bit of which is recorded by the corresponding light emitting diode 52. The resulting code is compared with a regulatory code that corresponds to and Prawna of diagnosed tachometer 55. The comparison result signal light-emitting diode 52 will make a conclusion on the technical state of the diagnosed tachometer 55.

Thus, a device for diagnosing devices of the power supply system, electric start-up, information and measuring system of a diesel engine in the modes of diagnosing diesel starting indicators, diagnosing fuel equipment and a tachometer measures the maximum electromagnetic power of the starter, the total resistance of the starter circuit, EMF, internal resistance, and battery short-circuit current battery, checks the performance of fuel equipment, determines the technical condition of the tachometer. The number of monitored parameters has been expanded.

Information sources:

1. Nechaev V.V. et al. Device for diagnosing diesel systems [Text] Patent for invention of the Russian Federation No. 2370745 IPC G01M 15/04, F02M 65/00 Applicant and patent holder Ryaz. military man. car Inst. - 2008115352/06; declared 04/18/2008; publ. 10/20/2009, bull. No. 29.

2. Nechaev V.V. et al. Device for diagnosing diesel systems and mechanisms [Text] Patent for utility model of the Russian Federation No. 844557 IPC G01M 15/00. Applicant and patent holder Ryaz. military man. car Inst. - 2009110722/22; declared 03/24/2009; publ. 07/10/2009, bull. No. 19.

3. Nechaev V.V. et al. Device for diagnosing diesel engines, systems and mechanisms [Text] Patent for utility model of the Russian Federation No. 95839 Russian Federation, IPC G01M 15/00. Applicant and patent holder Ryaz. military man. car institute - 2010109638/22; declared 03/15/2010; publ. 07/10/2010, Bull. No. 19.

Claims (1)

A device for diagnosing devices of the power system, electric start-up, information and measuring system of a diesel engine containing a stand base on which the tested high pressure fuel pump (TNVD), nozzles, graduated cylinders, a fuel distributor, upper and lower fuel tanks, a booster booster pump, a fuel filter, a pressure gauge damper, a pressure gauge, a fuel cylinder through which high pressure fuel lines (HPT) pass, and the fuel cylinder is connected to a high pressure battery Ia fuel and hydraulic oscillation damper with a fuel in the cylinder, and the shaft is placed the test disc pump mounted with a permanent magnet valve opening control hydraulic oscillation damper fuel and the permanent magnet timer top dead center (TDC) of the first cylinder; an electric circuit for detecting changes in fuel pressure in a fuel engine containing a fuel pressure sensor located in the fuel cylinder and connected by a switch and electric circuits to a current amplifier, analog-to-digital converter (ADC), a port and a computer, the computer being connected to the display; an electric circuit of the TDC marker of the first cylinder, comprising an electric coil located on the fuel pump housing and connected through an electric circuit to an electric unit; an electric control circuit for the spool of the fuel cylinder with a damper for hydraulic vibrations of the fuel, consisting of an electric coil mounted on the injection pump housing, a direct current amplifier and an electric coil for the spool of the fuel cylinder with a damper for hydraulic vibrations of the fuel, interconnected by an electric circuit, a DC voltmeter connected parallel to the vehicle’s battery and an ammeter with a current sensor mounted on a wire connecting the positive terminal One battery with a starter and clasping it with its own clamps, characterized in that it additionally includes a unit for tachometer diagnostics, mounted on the base of the stand, consisting of a logical element And, a differentiating circuit with a diode at the output, a resistor connected to the output of the logical output an element, a multivibrator operating in self-oscillating mode, a summing electronic counter, light-emitting diodes.

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