Device and method for synchronously measuring plunger lift and oil supply starting point of diesel engine

Abstract

The invention discloses a diesel engine plunger lift and oil supply starting point synchronous measurement device and method, and the device comprises a high-pressure oil pump, an oil guide cavity supporting barrel is installed in an oil outlet valve installation hole in the upper end of the high-pressure oil pump, and the upper end and the lower end of the oil guide cavity supporting barrel are respectively provided with an upper cover plate and a lower cover plate. Central holes are formed in the middle positions of the upper cover plate and the lower cover plate; a fixing support is installed at the upper end of the oil guide cavity supporting barrel, an electronic digital display stroke module is installed at the upper end of the fixing support, and the lower end of the electronic digital display stroke module is connected with a measuring rod. According to the diesel engine plunger lift and oil supply starting point synchronous measurement device and method, the problems of disassembly loss, manual errors and incapability of cross validation of data in a traditional method are solved, two-parameter in-situ synchronous measurement is realized, meanwhile, an oil outlet valve does not need to be disassembled and a plunger cavity does not need to be opened, risks such as foreign matter invasion are avoided, and the measurement precision and convenience are greatly improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of diesel engine detection, in particular to a diesel engine plunger lift and oil supply start point synchronous measurement device and method. BACKGROUND

[0002] In the field of diesel engines, accurate measurement of the oil supply advance angle is a key technical parameter for optimizing engine power performance and emission indicators.

[0003] The traditional measurement system is based on two independent measurement paths: (1) the drop oil method determines the oil supply start point by detecting the flow change of fuel in the oil pipe, but it needs to disassemble the oil outlet valve of the high-pressure oil pump and remove the internal precision components. This operation can cause the cumulative gap of the internal parts of the oil outlet valve to expand, affecting the sealing performance and service life of the oil outlet valve; (2) the pre-lift method uses mechanical instruments (such as traditional dial gauges) to track the displacement of the plunger, but it needs to disassemble the oil outlet valve and open the plunger cavity for manual reading. This operation has the risk of foreign matter intrusion and aggravates the wear of the components.

[0004] The above measurement methods cannot achieve synchronous measurement of the "plunger lift-oil supply start point" double parameters, resulting in the lack of correlation data between the oil supply advance angle and the plunger lift: too late or too early oil supply will cause problems such as high diesel fuel consumption, difficulty in starting, overheating, abnormality, and poor smoke color, and the measurement achieved by alternating manual operation of naked eye observation of oil droplets and manual adjustment of dial gauge readings still faces the bottleneck of insufficient synchronous accuracy and limited working condition adaptability. SUMMARY

[0005] The technical problem to be solved by the present application is to overcome the existing defects and provide a diesel engine plunger lift and oil supply start point synchronous measurement device and method to solve the problems of disassembly and wear, manual error, and data that cannot be cross-verified in traditional methods, achieve in-situ synchronous measurement of double parameters, and avoid the risk of foreign matter intrusion without disassembling the oil outlet valve and opening the plunger cavity, effectively solving the problems in the background art.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical scheme: a diesel engine plunger lift and oil supply start point synchronous measurement device, comprising a high-pressure oil pump, a guide oil chamber support barrel is installed in the upper end oil outlet valve mounting hole of the high-pressure oil pump, upper and lower ends of the guide oil chamber support barrel are respectively provided with an upper cover plate and a lower cover plate, and a center hole is arranged in the middle position of the upper cover plate and the lower cover plate;

[0007] A fixed support is installed at the upper end of the guide oil chamber support barrel, an electronic digital display stroke module is installed at the upper end of the fixed support, the lower end of the electronic digital display stroke module is connected with a measuring rod, and the lower end of the measuring rod passes through the center holes of the upper cover plate and the lower cover plate and contacts the top surface of the plunger of the high-pressure oil pump;

[0008] The center hole of the lower end cover is symmetrically provided with oil guide holes on both sides, one side of the oil guide cavity support barrel is provided with an inclined hole, one side of the oil guide cavity support barrel is provided with a transparent oil pipe, the drainage pipe of the transparent oil pipe is connected with the inclined hole, and the outer side of the transparent oil pipe is provided with a photoelectric liquid drop counting module for capturing the refractive index change of liquid drops.

[0009] As a preferred technical solution of the present application, the outer side of the lower end of the oil guide cavity support barrel is provided with external threads, and the oil guide cavity support barrel is connected with the oil outlet valve mounting hole of the high-pressure oil pump through threads.

[0010] As a preferred technical solution of the present application, a sealing ring groove is arranged in the center hole of the upper cover plate, and an O-ring is arranged in the sealing ring groove.

[0011] As a preferred technical solution of the present application, the upper cover plate and the lower cover plate are both threadedly connected with the oil guide cavity support barrel.

[0012] As a preferred technical solution of the present application, the photoelectric liquid drop counting module comprises an infrared emitter and a receiver, and the infrared emitter and the receiver are oppositely arranged on both sides of the transparent oil pipe.

[0013] A measurement method of a diesel engine piston stroke and oil supply start point synchronous measurement device, comprising the following steps:

[0014] S1: rotate the crankshaft, the piston of the high-pressure oil pump pushes the measuring rod upwards, the electronic digital display stroke module outputs the displacement signal in real time to the industrial computer, and a time curve is generated;

[0015] S2: as the crankshaft rotates, the camshaft of the high-pressure oil pump drives the piston to move, fuel flows into the transparent oil pipe through the oil guide hole of the lower cover plate and the inclined hole of the oil guide cavity support barrel, the liquid drops cause the refractive index of the infrared light path to change, and when the preset value is reached, the photoelectric liquid drop counting module generates a pulse signal, and the industrial computer synchronously triggers the electronic digital display stroke module to align the stroke and the liquid drop signal;

[0016] S3: observe the angle value on the flywheel of the diesel engine, determine the oil supply advance angle calibration value by the difference between the angle value of the flywheel at this time and the angle value of the flywheel corresponding to the top dead center of the first cylinder, and cross-verify by observing the display value on the electronic digital display stroke module.

[0017] Compared with the prior art, the present application has the following advantages: (1) the mechanical displacement signal of the plunger stroke and the optical drop signal of the oil supply starting point are collected at the same time reference, ensuring the alignment of the two signal time points and eliminating the timing error of the traditional method of observing drops by eyes and manual reading operation; (2) the oil guide cavity support barrel structure is used to replace the original high-pressure oil pump oil outlet valve, which retains the original fuel passage function and realizes in-situ synchronous measurement, realizes the guidance of the measuring rod while retaining the sealing, and avoids the risk of foreign matter intrusion; (3) the mechanical reference of the crank angle is cross-verified with electronic data, reducing the synchronization error and improving the measurement accuracy. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a structural schematic diagram of the present application;

[0019] Figure 2 is a structural schematic diagram of the oil guide cavity support barrel;

[0020] Figure 3 is a structural schematic diagram of the upper cover plate;

[0021] Figure 4 is a structural schematic diagram of the lower cover plate;

[0022] Figure 5 is a structural schematic diagram of the measuring rod;

[0023] Figure 6 is a structural schematic diagram of the electronic digital display stroke module;

[0024] Figure 7 is a structural schematic diagram of the photoelectric drop counting module.

[0025] In the figure: 1 oil guide cavity support barrel, 2 upper cover plate, 3 lower cover plate, 4 measuring rod, 5 electronic digital display stroke module, 6 fixed support, 7 O-ring, 8 transparent oil pipe, 9 photoelectric drop counting module, 10 high-pressure oil pump, 11 center hole, 12 oil guide hole, 13 inclined hole. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments (for the convenience of description and understanding, the following description is made with the upper side as the upper side). Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application. Figure 1

[0027] Please refer to Figures 1-7 ​The application provides a technical scheme: a diesel engine plunger lift and oil supply starting point synchronous measurement device, which comprises a high-pressure oil pump 10, an oil guide cavity support barrel 1, a measuring rod 4, a fixed support 6, an electronic digital display stroke module 5, a transparent oil pipe 8 and a photoelectric liquid drop counting module 9.

[0028] The upper end oil outlet valve mounting hole of the high-pressure oil pump 10 is provided with the oil guide cavity support barrel 1, the oil guide cavity support barrel 1 is made of 304 stainless steel, the original oil outlet valve is replaced and mounted on the high-pressure oil pump 10, and the upper end and the lower end of the oil guide cavity support barrel 1 are respectively provided with an upper cover plate 2 and a lower cover plate 3, and the middle positions of the upper cover plate 2 and the lower cover plate 3 are provided with a center hole 11.

[0029] The upper end of the oil guide cavity support barrel 1 is provided with the fixed support 6, the fixed support 6 is made of 6061 aluminum alloy, is connected with the oil guide cavity support barrel 1 through screws, the upper end of the fixed support 6 is provided with the electronic digital display stroke module 5, the electronic digital display stroke module 5 is a modified vernier caliper, and a built-in displacement sensor group outputs plunger lift data in real time.

[0030] The lower end of the electronic digital display stroke module 5 is connected with the measuring rod 4, the lower end of the measuring rod 4 penetrates through the center holes 11 of the upper cover plate 2 and the lower cover plate 3 and is in contact with the plunger top surface of the high-pressure oil pump 10, wherein the measuring rod 4 is made of 6061 aluminum alloy, and the contact force of the lower end of the measuring rod 4 against the plunger top surface is less than or equal to 5N.

[0031] The center hole 11 of the lower end cover 3 is symmetrically provided with oil guide holes 12 on both sides, one side of the oil guide cavity support barrel 1 is provided with an inclined hole 13, one side of the oil guide cavity support barrel 1 is provided with the transparent oil pipe 8, a drainage pipe of the transparent oil pipe 8 is connected with the inclined hole 13, and a fuel passage is formed.

[0032] The outer side of the transparent oil pipe 8 is provided with the photoelectric liquid drop counting module 9 for capturing the refractive index change of liquid drops, the photoelectric liquid drop counting module 9 comprises an infrared emitter and a receiver, the infrared emitter and the receiver are oppositely installed on the two sides of the transparent oil pipe 8, a fuel supply starting point pulse signal is generated by capturing the refractive index change of liquid drops.

[0033] In order to facilitate the quick disassembly and assembly of the oil guide cavity support barrel 1 and the high-pressure oil pump 10, the lower end outer side of the oil guide cavity support barrel 1 is provided with external threads, and the oil guide cavity support barrel 1 and the oil outlet valve mounting hole of the high-pressure oil pump 10 are connected through threads.

[0034] In order to prevent fuel from overflowing the oil guide cavity support barrel 1, a sealing ring groove is arranged in the center hole of the upper cover plate 2, an O-shaped ring 7 is arranged in the sealing ring groove, and the upper cover plate 2 and the measuring rod 4 are sealingly connected through the O-shaped ring 7.

[0035] In order to facilitate the installation of the upper cover plate 2 and the lower cover plate 3, the upper cover plate 2 and the lower cover plate 3 are threadedly connected with the oil guide cavity support barrel 1.

[0036] A measurement method of a diesel engine plunger lift and oil supply start point synchronous measurement device, comprising the following steps:

[0037] S1: installation process: sequentially install the lower cover plate 3, the measuring rod 4, and the upper cover plate 2, and ensure that the O-ring 7 is tightly sealed;

[0038] The electronic digital display stroke module 5 is fixedly connected with the oil guide cavity support barrel 1 through the fixing support 6;

[0039] The transparent oil pipe assembly 8 is installed in position with the photoelectric liquid drop counting module 9;

[0040] The original high-pressure oil pump 10 and the original oil outlet valve assembly are disassembled, and the installation surface is cleaned;

[0041] The lower part of the oil guide cavity support barrel 1 is screwed into the oil outlet valve mounting hole of the high-pressure oil pump 10;

[0042] S2: rotate the crankshaft, the plunger of the high-pressure oil pump 10 is pushed up to drive the measuring rod 4, the electronic digital display stroke module 5 outputs the displacement signal in real time to the industrial computer, and a time curve is generated;

[0043] S3: with the rotation of the crankshaft, the plunger is driven to move by the camshaft of the high-pressure oil pump 10, fuel flows into the transparent oil pipe 8 through the oil guide hole 12 of the lower cover plate 3 and the inclined hole 13 of the oil guide cavity support barrel 1, the liquid drop causes the refractive index of the infrared light path to change, and when the preset value is reached, the photoelectric liquid drop counting module 9 generates a pulse signal (at this time, an audible and visual prompt is given to determine the oil supply start point), and the industrial computer synchronously triggers the electronic digital display stroke module 5 to align the lift and the liquid drop signal;

[0044] S4: observe the angle value of the diesel engine flywheel (the flywheel is installed on the crankshaft and rotates with the crankshaft, and there is an angle scale on the circumference), and determine the oil supply advance angle calibration value by the difference between the angle value of the flywheel at this time and the angle value of the flywheel corresponding to the top dead center of the first cylinder, and cross verification can be performed by observing the displayed value of the electronic digital display stroke module 5.

[0045] The signal time mark is aligned through the configuration of a double-channel synchronous acquisition system, the fuel change signal in the oil pipe and the plunger lift trajectory are captured respectively, and the synchronous precision reaches ±0.1° of the crankshaft rotation angle.

[0046] The present application realizes in-situ synchronous measurement of double parameters, does not need to disassemble the oil valve and open the plunger cavity, avoids the risk of foreign matter invasion, avoids accelerating the wear of parts, cross verifies the mechanical reference of the crankshaft rotation angle and the electronic data, reduces the synchronous error, and greatly improves the measurement precision.

[0047] While the application has been shown and described with reference to particular embodiments thereof, it will be understood by those skilled in the art that various changes in form and details can be made therein without departing from the spirit and scope of the application. What is claimed is:

Claims

1. A synchronous measuring device for diesel engine plunger lift and fuel injection start point, comprising a high-pressure oil pump (10), characterized in that: The high-pressure oil pump (10) has an oil guide chamber support barrel (1) installed in the oil outlet valve mounting hole at the upper end. The upper and lower ends of the oil guide chamber support barrel (1) are respectively provided with an upper cover plate (2) and a lower cover plate (3). A center hole (11) is provided in the middle position of both the upper cover plate (2) and the lower cover plate (3). The upper end of the oil guide chamber support barrel (1) is equipped with a fixed bracket (6), the upper end of the fixed bracket (6) is equipped with an electronic digital display stroke module (5), the lower end of the electronic digital display stroke module (5) is connected to the measuring rod (4), and the lower end of the measuring rod (4) passes through the center hole (11) of the upper cover plate (2) and the lower cover plate (3) and contacts the top surface of the plunger of the high pressure oil pump (10). The lower end cap (3) has symmetrical oil guide holes (12) on both sides of the central hole (11). The oil guide cavity support barrel (1) has an oblique hole (13) on one side. The oil guide cavity support barrel (1) has a transparent oil pipe (8) on one side. The drain pipe of the transparent oil pipe (8) is connected to the oblique hole (13). The outer side of the transparent oil pipe (8) is provided with a photoelectric droplet counting module (9) for capturing the change of the refractive index of the droplets.

2. The synchronous measuring device for diesel engine plunger lift and fuel injection start point according to claim 1, characterized in that: The lower outer side of the oil guide cavity support barrel (1) is provided with an external thread, and the oil guide cavity support barrel (1) is connected to the oil outlet valve mounting hole of the high pressure oil pump (10) by a thread.

3. The synchronous measuring device for diesel engine plunger lift and fuel injection start point according to claim 1, characterized in that: A sealing groove is provided in the center hole of the upper cover plate (2), and an O-ring (7) is provided in the sealing groove. The upper cover plate (2) and the measuring rod (4) are sealed together by the O-ring (7).

4. The synchronous measuring device for diesel engine plunger lift and fuel injection start point according to claim 1, characterized in that: Both the upper cover plate (2) and the lower cover plate (3) are threadedly connected to the oil guide cavity support barrel (1).

5. The synchronous measuring device for diesel engine plunger lift and fuel injection start point according to claim 1, characterized in that: The photoelectric droplet counting module (9) includes an infrared transmitter and a receiver, which are installed opposite each other on both sides of the transparent oil pipe (8).

6. The measurement method of the synchronous measuring device for diesel engine plunger lift and fuel injection start point according to claims 1-5, characterized in that: Includes the following steps: S1: Turning the crankshaft causes it to rotate, and the piston of the high-pressure oil pump (10) moves upward to push the measuring rod (4). The electronic digital display stroke module (5) outputs the displacement signal in real time and transmits it to the industrial control computer to generate a time curve. S2: As the crankshaft rotates, it drives the high-pressure oil pump (10) camshaft to move the plunger. Fuel flows into the transparent oil pipe (8) through the oil guide hole (12) of the lower cover plate (3) and the inclined hole (13) of the oil guide chamber support barrel (1). The droplets cause the refractive index of the infrared light path to change. After reaching the preset value, the photoelectric droplet counting module (9) generates a pulse signal. The industrial control computer synchronously triggers the electronic digital display stroke module (5) to align the stroke and droplet signal. S3: Observe the angle value on the diesel engine flywheel. Determine the fuel injection advance angle calibration value by the difference between the flywheel angle value at this time and the flywheel angle value corresponding to the top dead center of the first cylinder. At the same time, cross-verify by observing the value displayed on the electronic digital display stroke module (5).

Images