CN109139323B - A compound fuel injection pump camshaft phase and fuel supply timing detection device and method - Google Patents

Abstract

The invention belongs to the technical field of diesel engine testing, and provides a device and a method for detecting the phase and the oil supply time of a cam shaft of a compound oil injection pump by an oil pump test bed. The device for detecting the phase and the oil supply time of the cam shaft of the compound oil injection pump by the oil pump test bed is provided, wherein the compound oil injection pump is formed by compounding an oil injection pump I and an oil injection pump II; the driving end of the fuel injection pump I is connected with the output end of the stepping driving motor; the output end of the stepping driving motor is provided with a gear disc I with a missing tooth, and the gear disc I corresponds to a magneto-electric sensor I; a gear disc II with teeth missing is arranged between the coupling I and the driving end of the fuel injection pump I; a magneto-electric sensor II is arranged corresponding to the gear plate II; the output end of the fuel injection pump I is connected with the driving end of the fuel injection pump II through a coupling II, and an angle indicator is arranged at the output end of the fuel injection pump II; the invention improves the accuracy of the oil pump test bed in measuring and evaluating the oil injection pump and the oil injector.

Description

A compound fuel injection pump camshaft phase and fuel supply timing detection device and method

technical field

The invention belongs to the technical field of diesel engine testing, and specifically describes a device and method for detecting the camshaft phase and fuel supply timing of a composite fuel injection pump on an oil pump test bench.

Background technique

The fuel injection pump is the most important part of the diesel engine, and it is regarded as the "heart" part of the diesel engine. Once the fuel injection pump fails, the entire diesel engine will malfunction. The fuel injection pump of the high-speed and high-power diesel engine with more than 12 cylinders generally adopts multi-cylinder fuel injection pumps. Flexible elastic couplings are connected together to form a composite multi-cylinder fuel injection pump. As the speed and load of the high-speed and high-power diesel engine increase during the test, the required fuel supply increases, resulting in a composite multi-cylinder fuel injection pump. The load on the composite multi-cylinder fuel injection pump is increased, and the loads on the fuel injection pumps of the compound multi-cylinder fuel injection pump are not exactly the same. The phase consistency of the camshafts of each fuel injection pump is changed, which in turn affects the fuel supply timing of each cylinder of the high-speed and high-power diesel engine.

The traditional oil pump test bench can complete the functions of fuel supply detection of single multi-cylinder fuel injection pump, pre-stroke adjustment of fuel injection pump, fuel injection pump and fuel injector non-uniformity detection and other functions. However, due to the limitations of equipment functions, it is impossible to perform the function of camshaft phase detection and fuel supply timing test of the compound multi-cylinder fuel injection pump, and it is impossible to detect the phase difference of the camshaft after the compound multi-cylinder fuel injection pump is connected together through a coupling , and the difference of fuel injection timing to further analyze the fuel injection pump.

Contents of the invention

In order to solve the above problems, the purpose of the present invention is to provide a device and method for detecting the camshaft phase and fuel supply timing of the compound fuel injection pump for the oil pump test bench.

For reaching above object of the invention, the present invention adopts following technical scheme:

A device for testing the camshaft phase and fuel supply timing of a composite fuel injection pump on an oil pump test bench. The composite fuel injection pump is composed of fuel injection pump I and fuel injection pump II; the driving end of the fuel injection pump I is connected to the The output end of the stepping drive motor is connected; the output end of the stepping driving motor is equipped with a toothless gear plate I, and the corresponding gear plate I is provided with a magnetic field for detecting the speed and phase signal of the output end of the stepping drive motor. Electric sensor Ⅰ; a tooth-missing gear plate II is installed between the coupling I and the driving end of the fuel injection pump Ⅰ; the structure of the gear plate II is the same as that of the gear plate Ⅰ; corresponding to the gear plate II There is a magnetic sensor II for detecting the rotational speed and phase signal of the driving end of the fuel injection pump I; the output end of the fuel injection pump I and the driving end of the fuel injection pump II are connected through the coupling II, and the output end of the fuel injection pump II is installed with The angle marker is used to detect the rotation speed and phase signal of the output end of the fuel injection pump II; the tops of the fuel injection pump I and the fuel injection pump II are provided with a plurality of oil outlet valves, and each of the oil outlet valves passes through the corresponding high-pressure The oil pipe is connected to the fuel injector; a pressure measurement joint I connected with the high pressure oil pipe is installed between the high pressure oil pipe and the corresponding oil outlet valve, and a pressure measurement joint I is installed on the pressure measurement joint I to detect the high pressure oil pipe pump The pressure sensor Ⅰ for the pressure of the oil pipe at the end; the pressure measuring joint II connected with the high-pressure oil pipe is installed between the high-pressure oil pipe and the corresponding injector, and a pressure measuring joint II is installed on the pressure measuring joint II to detect the nozzle end of the high-pressure oil pipe. The pressure sensor II of the oil pipe pressure; the magnetoelectric sensor I and the magnetoelectric sensor II are all connected with the pressure sensor I, the pressure sensor II and the host computer, and the synchronous acquisition is carried out; by comparing the motor output end and the fuel injection pump I drive Judging the phase consistency of the camshafts of each pump under the actual connection state of the two fuel injection pumps by the consistency of the speed and phase signals of the fuel injection pump II output terminal.

Corresponding to each of the fuel injectors, a measuring cup for measuring the fuel injection quantity of the fuel injector is provided.

The racks of the fuel injection pump I and the fuel injection pump II are connected together, and the rack adjustment device

Control the stroke of the rack; the rack adjustment device is installed at the input end of the fuel injection pump I, the protruding rack passes through the adjustment hole of the fixing bracket, and the elongation of the rack is fixed by the compression nuts at the front and rear of the adjustment hole; The determination of the bar extension is the length of the rack at the front end of the adjustment hole in the pulling state minus the length of the rack at the front end of the adjustment hole in the free state.

The method of detecting the camshaft phase and fuel supply timing of the composite fuel injection pump by using a device for detecting the camshaft phase and fuel supply timing of the compound fuel injection pump on the oil pump test bench is: connect the water and oil required to complete the test of the oil pump test bench Road-related supporting equipment, determine the angle difference between the grating reference position of the angle marker and the camshaft top dead center position of the last fuel delivery valve of fuel injection pump II, and determine the relative position of each fuel delivery valve of high-pressure fuel pipe I and fuel injection pump II relative to the last fuel injection pump II The angle difference of the upper dead center position of the camshaft of an oil delivery valve; start the stepping drive motor, set the measurement speed and cycle number; adjust the rack adjustment device, and set the rack stroke; use the host computer to synchronously collect different speeds and different rack strokes The speed and phase signals measured by the subscript instrument and the pressure sensor Ⅰ and pressure sensor Ⅱ1 are used to obtain the pressure data of the pump end and mouth end; in order to ensure the measurement accuracy and accuracy, the high pressure oil pipe Ⅰ and the oil outlet valve position of the fuel injection pump II When the oil pipe is detected, the pressure of all high-pressure oil pipe pump ends and mouth ends connected to the high-pressure oil pipe I and the fuel injection pump II are measured simultaneously; the speed and phase signals measured by the magnetoelectric sensor The position of missing teeth of the gear plate and gear plate II and the reference position of the grating of the angle marker are used as references to analyze the speed and phase of each revolution of the stepping drive motor, high-pressure oil pipe I and fuel injection pump II at different speeds and rack strokes Signal consistency, to judge the consistency of the camshaft phase of the high-pressure oil pipe I and the fuel injection pump II under the actual installation state of the compound fuel injection pump; obtain the different speeds and different The pressure curves of the pump end and nozzle end of the high-pressure oil pipe based on the rotation angle signal under the rack stroke;

Control rack travel. The rack adjusting device is installed at the input end of the fuel injection pump I, and the protruding rack passes through the adjusting hole of the fixing bracket, and the elongation of the rack is fixed by the compression nuts before and after the adjusting hole. The amount of rack extension is determined as the length of the rack at the front end of the adjustment hole in the pulled state minus the length of the rack at the front end of the adjustment hole in the free state.

Under the same speed and the same rack stroke, the corresponding rotation angle value of each pressure value point of the high-pressure oil pipe pump end and mouth end pressure curve of each oil outlet valve corresponding to the rack stroke is compared with the interval angle, and at the same time, the opening pressure and closing pressure of the oil outlet valve are obtained. The opening time, end time and duration of the oil outlet valve; analyze the consistency of the oil outlet rules of the high-pressure oil pipe I and the oil outlet valves of the fuel injection pump II; as shown in Figure 4, this is the high-pressure oil pipe of the first oil outlet valve of the fuel injection pump I The pressure curve at the pump end, the opening pressure of the outlet valve is 400bar, the corresponding camshaft rotation angle is -23deg, the closing pressure is 340 bar, the corresponding camshaft rotation angle is -1deg, and the fuel injection duration of the outlet valve is -1-(-23 )=22deg; according to this method, the opening pressure and closing pressure of all the oil outlet valves of the fuel injection pump I and the fuel injection pump II can be obtained to obtain the opening time, end time and duration of the oil outlet valves, that is, the oil outlet valves of the high-pressure fuel pipe I and the fuel injection pump II Consistency of the oil output law; replace different types of injectors for experiments, and obtain high-pressure oil pipe pump ends based on rotation angle signals at different speeds and different rack strokes when various injectors are replaced. , Nozzle end pressure curve; In the above test process, the end of each injector is equipped with a measuring cup, which can analyze the consistency of the oil volume of the high-pressure oil pipe I and the oil outlet valve of the fuel injection pump II under different speeds and different rack strokes.

The invention proposes a device for detecting the camshaft phase and fuel supply timing of a composite fuel injection pump on an oil pump test bench. The above technical scheme can realize the detection of the spray quality of the fuel injector, the flow detection of the fuel injector, and the detection of the fuel flow of the fuel injector. It can detect the phase consistency of the camshaft of each fuel injection pump at different speeds and different rack strokes of the compound fuel injection pump under actual working conditions, and the consistency of the pressure at the pump end and nozzle end of the high-pressure oil pipe; The scope of use of the equipment is expanded, and the accuracy of the fuel pump test bench for the measurement and evaluation of fuel injection pumps and fuel injectors is improved.

Description of drawings

Figure 1 is a schematic diagram of the compound fuel injection pump installed on the fuel pump test bench:

Figure 2 is a schematic diagram of the structure of the gear plate:

Fig. 3 is A-A sectional view of Fig. 2;

Figure 4 is a schematic diagram of the rack stroke adjustment device:

Fig. 5 is a schematic diagram of the pressure curve at the pump end;

Figure 6 is a schematic diagram of the mouth end pressure curve.

In the figure: 1. Stepping drive motor, 2. Gear disc Ⅰ, 3. Coupling Ⅰ, 4. Gear disc Ⅱ, 5. Fuel injection pump Ⅰ, 6. Coupling Ⅱ, 7. Fuel injection pump Ⅱ, 8. Angle marker, 9. High pressure oil pipe, 10. Pressure measuring joint Ⅰ, 11. Pressure measuring joint Ⅱ, 12. Fuel injector, 13. Measuring cup, 14. Slide rail, 15. Magnetic sensor Ⅱ, 16. Magnetic sensor Ⅰ, 17. Host computer, 18. Pressure sensor Ⅰ, 19. Pressure sensor Ⅱ, 21. Rack adjustment device, 22. Oil outlet valve, 23. Fixed bracket, 24. Front rack, 25. Compression nut.

Detailed ways

The specific embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings. Some non-essential improvements and adjustments made by those skilled in the art according to the contents of the present invention still belong to the present invention.

As shown in Figure 1, a device for detecting the camshaft phase and fuel supply timing of a compound fuel injection pump on an oil pump test bench. The compound fuel injection pump is composed of a fuel injection pump I5 and a fuel injection pump II7; the driving end of the fuel injection pump I5 The output end of the stepping drive motor 1 is connected to the output end of the stepping drive motor 1 through the coupling I3; the output end of the stepping drive motor 1 is equipped with a tooth-missing gear plate I2, and the corresponding gear plate I2 is provided for outputting the stepping drive motor The rotation speed and phase signal at the end are detected by the magnetoelectric sensor I16; the toothless gear plate II4 is installed between the coupling I3 and the driving end of the fuel injection pump I5; the structure of the gear plate II4 is the same as that of the gear plate I2; The structures of gear plate II4 and gear plate I2 are shown in Figure 2 and Figure 3; corresponding to the gear plate II4, there is a magnetoelectric sensor II15 for detecting the rotational speed and phase signal of the driving end of the fuel injection pump I; the fuel injection pump I5 The output end is connected to the driving end of the fuel injection pump II7 through the coupling II6, and the output end of the fuel injection pump II7 is equipped with an angle marker 8 to detect the speed and phase signal of the output end of the fuel injection pump II7; the fuel injection pump I5, The top of the fuel injection pump II7 is provided with a plurality of oil outlet valves 22, and each of the oil outlet valves 22 communicates with the fuel injector 12 through the corresponding high-pressure oil pipe 9; 22 is installed with a pressure measurement joint I10 connected with the high-pressure oil pipe, and a pressure sensor I18 for detecting the pressure of the oil pipe at the pump end of the high-pressure oil pipe is installed on the pressure measurement joint I; the high-pressure oil pipe and the corresponding fuel injector A pressure measurement joint II11 connected with the high-pressure oil pipe is installed between them, and a pressure sensor II19 for detecting the pressure of the oil pipe at the nozzle end of the high-pressure oil pipe is installed on the pressure measurement joint II; the magnetoelectric sensor I16, magnetoelectric Sensor II15, pressure sensor I18, and pressure sensor II19 are all connected to the host computer 17, and the magnetoelectric sensor I16 and magnetoelectric sensor II15 are used to measure the speed and phase signals of the gear plate I2 and gear plate II4 and communicate with the pressure sensor I10 , The pressure sensor II11 is connected with the upper computer 17, and performs synchronous acquisition. By comparing the consistency of the output end of motor 1, the driving end of fuel injection pump I5, and the output end of fuel injection pump II7, the phase consistency of the camshafts of each pump is judged under the actual connection state of the two fuel injection pumps.

Corresponding to each of the fuel injectors, a measuring cup for measuring the fuel injection quantity of the fuel injector is provided.

As shown in Figure 4, the racks of the fuel injection pump I and II are connected together, and the stroke of the rack is controlled by the rack adjustment device 21; the rack adjustment device 21 is installed at the input end of the fuel injection pump I5, extending The front end rack 24 passes the adjustment hole of the fixed bracket 23, and the elongation of the rack is fixed by the compression nut 25 before and after the adjustment hole. The amount of rack extension is determined as the length of the rack at the front end of the adjustment hole in the pulled state minus the length of the rack at the front end of the adjustment hole in the free state.

The method of detecting the camshaft phase and fuel supply timing of the composite fuel injection pump by using a device for detecting the camshaft phase and fuel supply timing of the compound fuel injection pump on the oil pump test bench is: connect the water and oil required to complete the test of the oil pump test bench Road and other related supporting equipment, adjust the tooth-missing position of gear plate I2 and gear plate II4 and the grating reference position of angle marker 8 to the same angle. Start stepper motor 1, set the measurement speed and number of cycles. Adjust the rack adjusting device 21 to set the rack stroke. Use the host computer 17 to synchronously collect the rotational speed and phase signals measured by the magnetoelectric sensor Ⅰ16, magnetoelectric sensor Ⅱ15, and angle marker 8 at different speeds and rack strokes, and use the tooth missing positions and angle markers of gear plate 2 and gear plate Ⅱ4 Using the raster reference position of instrument 8 as a reference, analyze the consistency of the speed and phase signals of stepper motor 1, high-pressure oil pipe I5 and fuel injection pump II7 per revolution at different speeds and rack strokes, and judge the performance of the compound fuel injection pump in practice. The phase consistency of the high-pressure oil pipe Ⅰ5 and the camshaft of the fuel injection pump Ⅱ7 in the installed state; judging method: before the test, adjust the tooth-missing positions of the gear plate Ⅰ2, the gear plate Ⅱ4 and the angle marker 8 to the same position, start the oil pump test bench, and the speed Fixed to 900r/min. Assuming that the number of teeth of gear plate I2 and gear plate II4 is 90 and one tooth is missing, and the number of gratings of angle marker 8 is 720 and one tooth is missing, the signals obtained by gear plate I2 and gear plate II4 through magnetic electromagnetic sensor I16 and magnetoelectric sensor II15 It is a positive rotation signal, and one tooth is a positive rotation signal, and there should be 90 missing 1 in one circle, and the signal obtained by the angle marker 8 is a square wave signal, and 720 should appear in one circle, and 1 missing. The square wave signal of the one-corner scale is eight times the forward rotation signal of gear plate Ⅰ2 and gear plate Ⅱ4. When the rotation speed and phase signal of the output end of the oil pump II7 are the same, except for the missing tooth position, when the gear plate I4 collects a positive rotation signal, the gear plate II4 should also just collect a positive rotation signal, and the angle marker 8 should just collect the 8 a square wave signal. When there is more or less than one positive rotation signal collected by the gear plate II4, it can be considered that the rotation speed increases or decreases, and the time difference is recorded. When the number of square wave signals collected by the angle marker 8 is more than or less than 8, it can be considered that the rotational speed increases or decreases, and the time difference is recorded. The consistency of the speed at each position of the output end of the stepping drive motor 1, the driving end of the fuel injection pump I5, and the output end of the fuel injection pump II7 is obtained after one rotation of the shaft system. Convert the speed signals of the output end of the stepping drive motor 1, the driving end of the fuel injection pump I5, and the output end of the fuel injection pump II7 into long-angle domain signals. The phase angle difference is calculated by the time difference between the gear plate I2, the gear plate II4 and the angle marker 8 in each positive rotation signal. Obtain the consistency of the phase angle of each position of the output end of the stepping drive motor 1, the driving end of the fuel injection pump I5, and the output end of the fuel injection pump II7 when the shaft system rotates one revolution;

Through the rotation speed of the fuel injection pump II7 detected by the angle marker 8, the signals of the pressure sensor I18 and the pressure sensor II19, the pressure curve of the pump end and mouth end of the high-pressure oil pipe is obtained with the rotation angle signal of the fuel injection pump II as the abscissa, and the rotation angle signal is obtained through The rotation speed of the angle marker 8 is obtained. The angle marker is 720 missing a grating, and a circle of 720 is missing a square wave signal. Each square wave signal represents 0.5deg. Before the test, determine the position of the angle marker 8 and the fuel injection pump. The included angle between the camshaft top dead center position at position 22 of each oil outlet valve of Ⅰ5 and Ⅱ7, start the oil pump test bench, measure the pressure curve of the pump end and mouth end of the high-pressure oil pipe and the speed signal of the angle marker. Convert the speed signal of the angle marker 8 into an angle signal, take the angle signal as the abscissa, and the pressure value as the ordinate, import the pressure data of the pump end and nozzle end of the oil pipe, and form a high-pressure oil pipe pump with the rotation angle signal of the fuel injection pump II as the abscissa End and mouth end pressure curves.

There is a fixed opening pressure for the oil outlet valve 22 of each fuel injection pump, assuming that the opening pressure is 400 bar, record the pressure on the left side of the pump end pressure curve of all high pressure oil pipes of the fuel injection pump I5 and fuel injection pump II7 when the pressure reaches 400 bar for the first time Corresponding crankshaft angle value, and calculate the difference between them, the difference is the actual fuel injection interval angle of each outlet valve of fuel injection pump Ⅰ5 and fuel injection pump Ⅱ7, for fuel injection pump Ⅰ and fuel injection pump Ⅱ, there is theoretical fuel injection interval angle The interval angle, comparing the difference between the actual fuel injection interval angle and the theoretical fuel injection interval angle, can determine the consistency of the fuel injection opening time of each fuel outlet valve 22 of the fuel injection pump. Similarly, the corresponding crankshaft angle value is obtained according to the oil outlet closing pressure of the oil outlet valve 22 of the fuel injection pump I5 and the fuel injection pump II7, and the difference between the crankshaft angle value of the oil outlet closing pressure of the oil outlet valve 22 and the crankshaft angle value of the oil outlet opening pressure of the oil outlet valve 22 is calculated. The crank angle difference between the fuel injection pump Ⅰ5 and the fuel injection pump Ⅱ7 is obtained by the fuel injection duration of the outlet valve 22, and the consistency of the fuel injection duration of the fuel injection pump Ⅰ5 and the fuel injection pump Ⅱ7 is compared with the fuel injection duration of the fuel outlet valve 22 of the fuel injection pump Ⅱ7 to judge the fuel injection pump The consistency of the fuel injection duration, fuel injection pressure and fuel injection timing data of the 22 positions of the fuel injection pumps of all fuel injection pumps Ⅰ5 and Ⅱ7, and judge the consistency of the fuel injection pressure and phase of each fuel injection valve position of all fuel injection pumps.

After the installation of each component is completed, connect the relevant supporting equipment such as water and oil circuits required for the test of the oil pump test bench, and determine the reference position of the grating of the angle marker 8 and the top dead center position of the camshaft of the last oil delivery valve of the fuel injection pump II7. Angle difference, determine the angle difference between the high-pressure oil pipe I5 and each outlet valve of the fuel injection pump II7 relative to the top dead center position of the camshaft of the last oil outlet valve of the fuel injection pump II7. Start stepper motor 1, set the measurement speed and number of cycles. Adjust the rack adjusting device 21 to set the rack stroke. Use the upper computer 17 to synchronously collect the speed and phase signals measured by the angle marker 8 at different speeds and different rack strokes, as well as the pressure sensor I18 and pressure sensor II19 to obtain the pressure data of the pump end and the mouth end; in order to ensure the measurement accuracy and accuracy, the When the high-pressure fuel pipe I5 and the high-pressure fuel pipe 9 at the outlet valve 22 of the fuel injection pump II7 are detected, the pressure of all high-pressure fuel pipe pump ends and mouth ends connected to the high-pressure fuel pipe I5 and fuel injection pump II7 is simultaneously measured. The rotation speed and phase signal measured by magnetoelectric sensor Ⅰ16, magnetoelectric sensor Ⅱ 15, and angle marker 8 are based on the position of missing teeth of gear plate 2 and gear plate Ⅱ 4 and the reference position of the grating of angle marker 8, and are analyzed at different speeds, The consistency of the speed and phase signals of the stepping motor 1, high-pressure fuel pipe I5 and fuel injection pump II7 per revolution under different rack strokes can be used to judge the camshaft phase of the high-pressure fuel pipe I5 and fuel injection pump II7 in the actual installation state of the composite fuel injection pump consistency. Obtain the pressure curves of the high-pressure fuel pipe Ⅰ5 and fuel injection pump II7 based on the rotation angle signal at the pump end and mouth end of the high-pressure fuel pipe 9 at different speeds and different rack strokes without replacing the injector 12; as shown in Figure 5 and Figure 6, Figure 5 is the pump end curve of the high-pressure oil pipe based on the rotation angle signal, and Figure 6 is the nozzle end curve of the high-pressure oil pipe based on the rotation angle signal. The two curves take the rotation angle signal of the fuel injection pump II as the abscissa and the pressure value as the ordinate.

Under the same rotation speed and the same rack stroke, each oil outlet valve 22 corresponds to the pump end and mouth end pressure curve of the high-pressure oil pipe 9, and the rotation angle value corresponding to each pressure value point is compared with the interval angle. The closing pressure is used to obtain the opening time, end time and duration of the oil delivery valve; the consistency of the oil delivery law of each delivery valve 22 of the high-pressure oil pipe Ⅰ5 and the fuel injection pump Ⅱ7 is analyzed.

Different types of fuel injectors were replaced for the test, and the pressure curves of the high-pressure fuel pipe pump end and mouth end of the high-pressure fuel pipe I5 and fuel injection pump II7 based on the rotation angle signal were obtained at different speeds and different rack strokes under the condition of replacing various injectors.

Under the same rotation speed and the same rack stroke, the rotation angle values corresponding to each pressure value point of the high-pressure oil pipe 9 pump end and nozzle end pressure curve corresponding to each oil outlet valve 22 are compared by removing the interval angle, and at the same time, according to the opening pressure and The closing pressure results in the opening time, closing time and duration of the injector 12 . Analyze the consistency of fuel injection rules of each fuel injector 12.

During the above test process, the end of each injector 12 is equipped with a measuring cup 13, which can analyze the consistency of the oil volume of the high-pressure oil pipe I5 and the oil outlet valve of the fuel injection pump II7 under different speeds and rack strokes.

The camshaft phase and fuel supply timing detection device and method of the compound fuel injection pump adopt the angle marker 365C of AVL Lister Testing Equipment Co., Ltd.

Claims (3)

1. A device that is used for oil pump test bench to detect compound injection pump camshaft phase place and oil feed moment, its characterized in that: the compound fuel injection pump is formed by compounding a fuel injection pump I and a fuel injection pump II; the driving end of the fuel injection pump I is connected with the output end of the stepping driving motor through a coupling I; the output end of the stepping driving motor is provided with a gear disc I with a missing tooth, and a magneto-electric sensor I for detecting the rotating speed and phase signals of the output end of the stepping driving motor is arranged corresponding to the gear disc I; a gear disc II with teeth missing is arranged between the coupling I and the driving end of the fuel injection pump I; the structure of the gear plate II is the same as that of the gear plate I; a magneto-electric sensor II for detecting the rotating speed and phase signals of the driving end of the fuel injection pump I is arranged corresponding to the gear plate II; the output end of the fuel injection pump I is connected with the driving end of the fuel injection pump II through a coupling II, and an angle indicator is arranged at the output end of the fuel injection pump II and used for detecting the rotating speed and phase signals of the output end of the fuel injection pump II; the top of the oil injection pump I and the top of the oil injection pump II are respectively provided with a plurality of oil outlet valves, and each oil outlet valve is communicated with an oil injector through a corresponding high-pressure oil pipe; a pressure measuring joint I communicated with the high-pressure oil pipe is arranged between the high-pressure oil pipe and the corresponding oil outlet valve, and a pressure sensor I used for detecting the oil pipe pressure at the pump end of the high-pressure oil pipe is arranged on the pressure measuring joint I; a pressure measuring joint II communicated with the high-pressure oil pipe is arranged between the high-pressure oil pipe and the corresponding oil sprayer, and a pressure sensor II used for detecting the pressure of the oil pipe at the nozzle end of the high-pressure oil pipe is arranged on the pressure measuring joint II; the phase consistency of each pump camshaft in the actual connection state of the two fuel injection pumps is judged by comparing the consistency of the rotation speeds and phase signals of the output end of the motor, the driving end of the fuel injection pump I and the output end of the fuel injection pump II; the rack of the oil injection pump I and the rack of the oil injection pump II are connected together, and the stroke of the rack is controlled by the rack adjusting device; the rack adjusting device is arranged at the input end of the oil injection pump I, and the extending racks penetrate through adjusting holes of the fixed bracket and fix the elongation of the racks through compression nuts at the front and rear sides of the adjusting holes; the determination of the amount of rack extension is the length of the rack at the front end of the lifting state adjusting hole minus the length of the rack at the front end of the free state adjusting hole.

2. The device for detecting the phase and the oil supply time of the camshaft of the compound oil injection pump by using the oil pump test bed as claimed in claim 1, wherein: and a measuring cup for measuring the oil injection quantity of the oil injector is arranged corresponding to each oil injector.

3. The method for detecting the phase and the oil supply time of the composite oil injection pump camshaft by using the device for detecting the phase and the oil supply time of the composite oil injection pump camshaft by the oil pump test stand according to any one of claims 1-2 comprises the following steps:

the method comprises the steps of connecting water and oil-way related matched equipment required by completing an oil pump test bed test, determining the angle difference between a grating reference position of an angle indicator and the top dead center position of a last oil outlet valve cam shaft of an oil injection pump II, and determining the angle difference between each oil outlet valve of a high-pressure oil pipe I and the oil injection pump II relative to the top dead center position of the last oil outlet valve cam shaft of the oil injection pump II; starting a stepping driving motor, and setting a measurement rotating speed and a circulation number; the rack adjusting device is used for adjusting the rack stroke; synchronously acquiring rotation speed and phase signals measured by angle markers under different rotation speeds and different rack strokes by using an upper computer, and measuring by a pressure sensor I and a pressure sensor II 1 to obtain pressure data of a pump end and a mouth end; in order to ensure measurement accuracy and precision, when the high-pressure oil pipe of each oil outlet valve position of the high-pressure oil pipe I and the oil injection pump II is detected, the pressures of the pump ends and the nozzle ends of all the high-pressure oil pipes connected with the high-pressure oil pipe I and the oil injection pump II are synchronously measured; the rotation speed and phase signals measured by the magneto-electric sensor I, the magneto-electric sensor II and the angle marker are used as references, the missing tooth positions of the gear disc and the gear disc II and the grating reference positions of the angle marker are used as references, the consistency of the rotation speed and phase signals of each rotation of the stepping driving motor, the high-pressure oil pipe I and the oil injection pump II under different rotation speeds and different rack strokes is analyzed, and the consistency of the camshaft phases of the high-pressure oil pipe I and the oil injection pump II in the actual installation state of the compound oil injection pump is judged; obtaining pressure curves of a high-pressure oil pipe pump end and a nozzle end based on corner signals under different rotation speeds and different rack strokes of the high-pressure oil pipe I and the oil injection pump II under the condition of not replacing the oil injector; the rack of the oil injection pump I and the rack of the oil injection pump II are connected together, and the stroke of the rack is controlled by a rack adjusting device; the rack adjusting device is arranged at the input end of the oil injection pump I, and the extending racks penetrate through adjusting holes of the fixed bracket and fix the elongation of the racks through compression nuts at the front and rear sides of the adjusting holes; the determination of the extension amount of the racks is that the length of the racks at the front end of the lifting state adjusting hole is subtracted by the length of the racks at the front end of the free state adjusting hole; comparing the rotation angle value removal interval angle corresponding to each pressure value point of the pressure curve of the pump end and the mouth end of the high-pressure oil pipe corresponding to each oil outlet valve under the same rotation speed and the same rack stroke, and obtaining the opening time, the ending time and the duration of the oil outlet valve according to the opening pressure and the closing pressure of the oil outlet valve; analyzing the consistency of oil discharge rules of all oil outlet valves of the high-pressure oil pipe I and the oil injection pump II; the oil injection valve is characterized in that the oil injection valve is a high-pressure oil pipe pump end pressure curve of a first oil outlet valve of an oil injection pump I, the opening pressure of the oil outlet valve is 400bar, the corresponding cam shaft rotation angle is-23 deg, the closing pressure is 340 bar, the corresponding cam shaft rotation angle is-1 deg, and the oil injection duration of the oil outlet valve is-1- (-23) =22 deg; the method is used for obtaining the opening pressure and the closing pressure of all the oil outlet valves of the oil injection pump I and the oil injection pump II, and obtaining the opening time, the ending time and the duration of the oil outlet valves, namely the consistency of the oil outlet rules of the oil outlet valves of the high-pressure oil pipe I and the oil injection pump II; the method comprises the steps of replacing different types of oil injectors for testing, and obtaining pressure curves of a pump end and a nozzle end of the high-pressure oil pipe based on corner signals under different rotation speeds and different rack strokes of the high-pressure oil pipe I and the oil injection pump II under the condition of replacing various oil injectors; in the test process, measuring cups are arranged at the tail ends of all the oil injectors, and the consistency of the oil quantity of the high-pressure oil pipe I and the oil outlet valve of the oil injection pump II under different rotating speeds and different rack strokes can be analyzed.