Testing device for low-pressure gear pump of high-pressure common rail system

Abstract

The utility model provides a testing device for a low-pressure gear pump of a high-pressure common rail system, and particularly relates to the technical field of high-pressure common rail fuel pumps of diesel engines, which comprises a transmission assembly, a sealing assembly, a gear pump fixing assembly, a gear pump pressure monitoring and control assembly, a support L-shaped plate and a hydraulic joint assembly, according to the testing device for the low-pressure gear pump of the high-pressure common rail system, the low-pressure gear pump is connected with a gear pump driving shaft through an external variable frequency motor for transmission, and the required rotating speed is obtained. The opening degree of the control valve is adjusted in a closed-loop mode through an external control system and the pressure sensor of the device, so that output pressure or flow needed by performance testing is obtained. Different types of low-pressure gear pumps are tested by replacing different gear pump driving shafts, so that the purpose of saving the test period and resources is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of diesel engine high-pressure common rail fuel pumps, in particular to a test device for a low-pressure gear pump in a high-pressure common rail system. Background Technique

[0002] Adopting a high-pressure common rail fuel injection system on a diesel engine has become one of the main development trends of diesel engine technology in the world today and is an important means for diesel engines to reduce pollutant emissions. The high-pressure common rail fuel injection system can not only achieve stable high-pressure injection and a perfect combustion process, but also independently control the fuel injection characteristics, greatly improving the power performance, economy and emissions of the diesel engine.

[0003] The high-pressure common rail fuel system includes components such as a common rail pump, a common rail pipe, an injector, an ECU, and sensors. Fuel is input from the fuel tank to the common rail pump through a fuel filter, pressurized in the plunger chamber and then sent into the common rail pipe. The pressure in the common rail pipe is controlled according to the pressure regulation signal sent by the ECU. The fuel is supplied to the injector through a high-pressure fuel pipe, and the injector injects the fuel into the combustion chamber of the diesel engine according to the command sent by the ECU for combustion to provide the required driving power or torque. The common rail pump is an important component of the high-pressure common rail fuel injection system. The common rail pump sucks fuel from the fuel tank into the distribution valve of the common rail pump through its own low-pressure gear pump, then supplies the fuel to the common rail pipe as required through the distribution valve, and injects high-pressure fuel into the engine cylinder at an appropriate time through the injector for combustion to provide the required driving power or torque. Therefore, the low-pressure gear pump has an important impact on the performance of the common rail pump, and it is of great significance to study its related performance. The related device for its performance test plays an important role in specific applications. Summary of the Invention

[0004] The purpose of the utility model is to provide a test device for a low-pressure gear pump in a high-pressure common rail system to solve the problem proposed in the above background technique that the common rail pump is an important component of the high-pressure common rail fuel injection system. The common rail pump sucks fuel from the fuel tank into the distribution valve of the common rail pump through its own low-pressure gear pump, then supplies the fuel to the common rail pipe as required through the distribution valve, and injects high-pressure fuel into the engine cylinder at an appropriate time through the injector for combustion to provide the required driving power or torque. Therefore, the low-pressure gear pump has an important impact on the performance of the common rail pump, and it is of great significance to study its related performance.

[0005] To achieve the above object, the utility model provides the following technical solutions: A test device for a low-pressure gear pump of a high-pressure common rail system, including a transmission assembly, a sealing assembly, a gear pump fixing assembly, a gear pump pressure monitoring and control assembly, a supporting L-shaped plate, and a hydraulic joint assembly. The transmission assembly is installed on the gear pump fixing assembly, the transmission assembly penetrates through the sealing assembly, the hydraulic joint assembly is arranged outside the gear pump fixing assembly, the gear pump pressure monitoring and control assembly is connected to the gear pump fixing assembly through the hydraulic joint assembly, and the gear pump fixing assembly is arranged on one side of the supporting L-shaped plate.

[0006] Preferably, the transmission assembly includes a transmission shaft, a transmission bearing, a first circlip, a front bearing adjusting washer, a rear bearing adjusting washer, and an inner bearing adjusting washer. The transmission bearing is in interference fit with the outer side of the transmission shaft. The inner bearing adjusting washer and the first circlip are arranged at one end of the transmission shaft. The front bearing adjusting washer is arranged on one side of the transmission bearing, and the rear bearing adjusting washer is arranged on the other side of the transmission bearing.

[0007] Preferably, the sealing assembly includes an adjusting washer, a hydraulic oil seal, and a second circlip. The hydraulic oil seal is connected to the gear pump fixing plate in interference fit. The adjusting washer is arranged on one side of the hydraulic oil seal, and the second circlip is arranged on the other side of the hydraulic oil seal.

[0008] Preferably, the gear pump fixing assembly includes a gear pump fixing plate and a bearing retaining ring; the bearing retaining ring and the gear pump fixing plate are in precise clearance fit.

[0009] Preferably, the gear pump pressure monitoring and control assembly includes a mounting valve block, a control valve, a pressure sensor, and a standard hydraulic joint. An orifice is provided on the mounting valve block. The control valve is connected to the mounting valve block through the orifice. The pressure sensor is connected to the mounting valve block by a standard thread. The gear pump pressure monitoring and control assembly is connected to and hydraulically sealed with the hydraulic joint assembly on the gear pump fixing assembly through the standard hydraulic joint.

[0010] Compared with the prior art, the beneficial effect of the utility model is that: for the test device of the low-pressure gear pump of the high-pressure common rail system, the low-pressure gear pump is driven by an external variable-frequency motor connected to the gear pump drive shaft to obtain the required rotational speed. The opening of the control valve is adjusted in a closed-loop manner by an external control system and the pressure sensor of this device to obtain the output pressure or flow rate required for performance testing. By replacing different gear pump drive shafts, different types of low-pressure gear pumps can be tested, so as to achieve the purpose of saving the test cycle and resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a hydraulic system diagram;

[0012] Figure 2It is a schematic structural diagram of the present utility model;

[0013] Figure 3 It is a schematic structural diagram of the transmission component of the present utility model;

[0014] Figure 4 It is a schematic structural diagram of the sealing component of the present utility model;

[0015] Figure 5 It is a schematic structural diagram of the gear pump fixing component of the present utility model;

[0016] Figure 6 It is a schematic structural diagram of the pressure monitoring and control valve component of the present utility model;

[0017] Figure 7 It is a schematic diagram of the supporting L-shaped plate of the present utility model.

[0018] In the figure: 1. Transmission component; 2. Sealing component; 3. Gear pump fixing component; 4. Gear pump pressure monitoring and control component; 5. Supporting L-shaped plate; 6. Hydraulic joint component; 1-1. Transmission shaft; 1-3. Transmission bearing; 1-6. First circlip; 1-2. Front adjusting washer for bearing; 1-4. Rear adjusting washer for bearing; 1-5. Inner ring adjusting washer for bearing; 2-3. Adjusting washer; 2-2. Hydraulic oil seal; 2-1. Second circlip; 3-1. Gear pump fixing plate; 3-2. Bearing retaining ring; 4-3. Installation valve block; 4-1. Control valve; 4-2. Pressure sensor; 4-4. Standard hydraulic joint. Specific embodiments

[0019] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments in the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0020] It should be noted that the structures, ratios, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those familiar with this technology to understand and read, and are not used to limit the limited conditions that can be implemented in this application. Therefore, they do not have technical substance significance. Any modification of the structure, change of the proportional relationship, or adjustment of the size, without affecting the effects that can be produced by this application and the purposes that can be achieved, should still fall within the scope that can be covered by the technical content disclosed in this application. Embodiment

[0021] Please refer to Figure 1 、 Figure 2 、 Figure 3 、 Figure 4, Figure 5 , Figure 6 and Figure 7 , a test device for a low-pressure gear pump of a high-pressure common rail system of the present utility model: includes a transmission assembly 1, a sealing assembly 2, a gear pump fixing assembly 3, a gear pump pressure monitoring and control assembly 4, a supporting L-shaped plate 5, and a hydraulic joint assembly 6. The transmission assembly 1 is installed on the gear pump fixing assembly 3, the transmission assembly 1 penetrates through the sealing assembly 2, the hydraulic joint assembly 6 is arranged outside the gear pump fixing assembly 3, the gear pump pressure monitoring and control assembly 4 is connected to the gear pump fixing assembly 3 through the hydraulic joint assembly 6, and the gear pump fixing assembly 3 is arranged on one side of the supporting L-shaped plate 5.

[0022] Further, the transmission assembly 1 includes a transmission shaft 1-1, a transmission bearing 1-3, a first circlip 1-6, a bearing front adjusting washer 1-2, a bearing rear adjusting washer 1-4, and a bearing inner ring adjusting washer 1-5. The transmission bearing 1-3 is in interference fit with the outside of the transmission shaft 1-1. The bearing inner ring adjusting washer 1-5 and the first circlip 1-6 are arranged at one end of the transmission shaft 1-1. The bearing front adjusting washer 1-2 is arranged on one side of the transmission bearing 1-3, and the bearing rear adjusting washer 1-4 is arranged on the other side of the transmission bearing 1-3. Precise connection is carried out through the measurement of the front and rear axial distances. The transmission bearing 1-3 and the transmission shaft 1-1 are in interference fit, and the two are press-fitted and assembled, and the bearing inner ring adjusting washer 1-5 and the first circlip 1-6 are used for stopping and fixing at the other end. When the transmission assembly 1 is assembled, the axial movement of the transmission shaft in its axial direction is controlled by adjusting the bearing front adjusting gasket 1-2 and the bearing rear adjusting gasket 1-4 to meet the actual situation of the installation of the low-pressure fuel transfer pump on the common rail pump.

[0023] Further, the sealing assembly 2 includes an adjusting washer 2-3, a hydraulic oil seal 2-2, and a second circlip 2-1. The hydraulic oil seal 2-2 is connected to the gear pump fixing plate 3-1 in interference fit. The adjusting washer 2-3 is arranged on one side of the hydraulic oil seal 2-2, and the circlip 2-1 is arranged on the other side of the hydraulic oil seal 2-2. The hydraulic oil seal 2-2 and the gear pump fixing plate 3-1 are in interference fit and press-fitted. Before press-fitting, its appropriate position is adjusted through the adjusting washer 2-3, and the circlip 2-1 is used for stopping and fixing. The hydraulic oil seal 2-2 is adjusted to an appropriate position through the adjusting washer 2-3 and is tightened and fixed by the circlip 2-1, and is matched with the transmission shaft 1-1 in the transmission assembly 1 to achieve a sealing effect. When the sealing assembly 2 is assembled, the axial movement of the oil seal during assembly caused by the dimensional error generated during machining is offset by replacing the adjusting washer 2-3, improving the sealing effect and service life of the oil seal.

[0024] Further, the gear pump fixing assembly 3 includes a gear pump fixing plate 3-1 and a bearing retaining ring 3-2; the bearing retaining ring 3-2 and the gear pump fixing plate 3-1 are in precise clearance fit. The outer ring of the drive bearing 1-3 in the drive assembly 1 and the inner ring of the gear pump fixing plate 3-1 are in precise clearance fit. The position is adjusted using the front bearing adjusting washer 1-2 and the rear bearing adjusting washer 1-4, and they are locked and fixed with bolts. The gear pump fixing plate 3-1 has oil passages required for gear pump testing and grooves or screw threads for installing related components.

[0025] Further, the gear pump pressure monitoring and control assembly 4 includes a mounting valve block 4-3, a control valve 4-1, a pressure sensor 4-2, and a standard hydraulic joint 4-4. The mounting valve block 4-3 is provided with orifices. The control valve 4-1 is connected to the mounting valve block 4-3 through the orifices. The pressure sensor 4-2 is connected to the mounting valve block 4-3 by standard threads. The gear pump pressure monitoring and control assembly 4 is connected and hydraulically sealed to the hydraulic joint assembly 6 on the gear pump fixing assembly 3 through the standard hydraulic joint 4-4. The control valve is in the form of a spool valve, and its opening degree is controlled by an external controller to achieve a throttling effect and regulate the pressure of the gear pump under test. The pressure sensor 4-2 is used to monitor the pipeline pressure at the oil outlet of the gear pump and feedback it to the external controller.

[0026] Working principle: The low-pressure gear pump is driven by an external variable-frequency motor connected to the gear pump drive shaft to obtain the required speed. The opening degree of the control valve is adjusted in a closed-loop manner through the external control system and the pressure sensor of this device to obtain the output pressure or flow rate required for performance testing. By replacing different gear pump drive shafts, different types of low-pressure gear pumps can be tested, thereby achieving the purpose of saving the test cycle and resources.

[0027] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A test device for a low-pressure gear pump of a high-pressure common rail system, comprising a transmission assembly (1), a sealing assembly (2), a gear pump fixing assembly (3), a gear pump pressure monitoring and control assembly (4), a supporting L-shaped plate (5) and a hydraulic joint assembly (6), characterized in that: The transmission assembly (1) is mounted on the gear pump fixing assembly (3); the transmission assembly (1) penetrates the sealing assembly (2); the hydraulic joint assembly (6) is arranged on the outside of the gear pump fixing assembly (3); the gear pump pressure monitoring and control assembly (4) is connected to the gear pump fixing assembly (3) via the hydraulic joint assembly (6); and the gear pump fixing assembly (3) is arranged on one side of the supporting L-shaped plate (5).

2. A test device for a low-pressure gear pump of a high-pressure common rail system according to claim 1, characterized in that: The transmission assembly (1) comprises a transmission shaft (1-1), a transmission bearing (1-3), a first retaining spring (1-6), a bearing front adjustment washer (1-2), a bearing rear adjustment washer (1-4) and a bearing inner ring adjustment washer (1-5); the transmission bearing (1-3) is interference-fitted on the outer side of the transmission shaft (1-1); the bearing inner ring adjustment washer (1-5) and the first retaining spring (1-6) are arranged at one end of the transmission shaft (1-1); a bearing front adjustment washer (1-2) is arranged on one side of the transmission bearing (1-3); and a bearing rear adjustment washer (1-4) is arranged on the other side of the transmission bearing (1-3).

3. A test device for a low-pressure gear pump of a high-pressure common rail system according to claim 1, characterized in that: The sealing assembly (2) comprises an adjusting washer (2-3), a hydraulic oil seal (2-2) and a second retaining spring (2-1); the hydraulic oil seal (2-2) is connected to a gear pump fixing plate (3-1) by interference fit; an adjusting washer (2-3) is arranged on one side of the hydraulic oil seal (2-2) and a second retaining spring (2-1) is arranged on the other side of the hydraulic oil seal (2-2).

4. A test device for a low-pressure gear pump of a high-pressure common rail system according to claim 1, characterized in that: The gear pump fixing assembly (3) comprises a gear pump fixing plate (3-1) and a bearing retaining ring (3-2); the bearing retaining ring (3-2) and the gear pump fixing plate (3-1) are precisely clearance matched.

5. A test device for a low-pressure gear pump of a high-pressure common rail system according to claim 1, characterized in that: The gear pump pressure monitoring and control component (4) comprises a mounting valve block (4-3), a control valve (4-1), a pressure sensor (4-2) and a standard hydraulic connector (4-4); an orifice is provided on the mounting valve block (4-3); the control valve (4-1) is connected to the mounting valve block (4-3) via the orifice; the pressure sensor (4-2) is connected to the mounting valve block (4-3) via a standard thread; the gear pump pressure monitoring and control component (4) is connected to and hydraulically sealed with a hydraulic connector component (6) on a gear pump fixing component (3) via the standard hydraulic connector (4-4).

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