Plunger and barrel assembly of fuel injection pump of marine diesel engine

Abstract

The utility model discloses a plunger and barrel assembly of a fuel injection pump of a marine diesel engine, and relates to the technical field of plunger and barrel assemblies. A connecting cavity is formed in the connecting cap, a piston mechanism is arranged in the plunger sleeve and comprises an oil outlet valve, a first buffer spring is connected to the top of the oil outlet valve, a plunger shaft is arranged in the plunger sleeve, an attaching pad is arranged at the top of the plunger shaft, the top of the attaching pad is attached to the oil outlet valve, and a second buffer spring is arranged at the bottom of the plunger shaft. And buffer bases are mounted at the bottoms of the second buffer springs. Through the arrangement of a piston mechanism, after an oil inlet groove conveys oil into a connecting cap and a plunger sleeve, an oil outlet valve and a plunger shaft can descend, after the oil is conveyed to an oil injection hole to be discharged, a first buffer spring can drive the oil outlet valve to reset, and a second buffer spring can also drive the plunger shaft to reset; therefore, when the equipment is reset, the equipment can be more convenient to reset.

Description

Technical Field

[0001] This utility model relates to the field of plunger assembly technology, specifically to a plunger assembly for a marine diesel engine fuel injection pump. Background Technology

[0002] The plunger assembly of a marine diesel engine injection pump is a core component of the diesel injection system, primarily used for precise control of fuel injection pressure, quantity, and timing. Its performance directly affects the diesel engine's power, economy, and emissions. However, existing marine diesel engine injection pump plunger assemblies have some shortcomings, such as:

[0003] Application No.: CN202420157282.5 discloses a high-pressure fuel injection pump plunger assembly. The connector part of the device can be made of a lower-cost casting. At the same time, the plunger head stores lubricating oil inside and releases oil through the oil hole to lubricate the plunger head. However, in actual use, the device is difficult to drive the piston mechanism to reset, which may lead to oil leakage in the plunger assembly during use.

[0004] Therefore, we proposed a plunger assembly for marine diesel engine injection pumps to address the problems mentioned above. Utility Model Content

[0005] The purpose of this utility model is to provide a plunger assembly for a marine diesel engine injection pump, in order to solve the problem mentioned in the background art that the plunger assemblies of injection pumps on the market are difficult to drive the piston mechanism to reset, which may lead to oil leakage during the use of the plunger assembly.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a marine diesel engine fuel injection pump plunger assembly, including a connecting cap and a plunger sleeve installed at the bottom of the connecting cap, wherein the top of the connecting cap is provided with an oil inlet groove;

[0007] The connecting cap has a connecting cavity inside, and the plunger sleeve has a piston mechanism inside. The piston mechanism includes an oil outlet valve. The top of the oil outlet valve is connected to a first buffer spring. The plunger sleeve has a plunger shaft inside, and the top of the plunger shaft has a fitting pad. The top of the fitting pad fits against the oil outlet valve. The bottom of the plunger shaft has a second buffer spring, and the bottom of the second buffer spring is equipped with a buffer base.

[0008] By setting up the piston mechanism, after the oil inlet groove transmits the oil to the connecting cap and the plunger sleeve, the oil outlet valve and the plunger shaft will descend. After the oil is discharged through the oil inlet hole, the first buffer spring will drive the oil outlet valve to reset, and the second buffer spring will also drive the plunger shaft to reset, making the device more convenient to reset.

[0009] As a preferred technical solution of this utility model, a connecting bolt is provided on the top of the connecting cap, and the connecting cap is fixedly connected to other equipment through the connecting bolt.

[0010] The above technical solution makes the top of the connector cap more stable when it is fixedly connected to other devices, thereby increasing the stability of the device during installation.

[0011] As a preferred technical solution of this utility model, a sealing groove is provided on the outer side of the plunger sleeve, and the plunger sleeve is sealed to the bottom of the connecting cap through the sealing groove.

[0012] The above technical solution enables the plunger sleeve to be more stable when sealing with the connecting cap, thereby increasing the stability of the equipment during installation.

[0013] As a preferred technical solution of this utility model, a wear-resistant ring is provided inside the plunger sleeve, and the inner side of the wear-resistant ring is slidably connected to the plunger shaft, and the inner side of the wear-resistant ring is slidably connected to the oil outlet valve.

[0014] The above technical solution enables the wear-resistant ring to protect the inside of the plunger sleeve when the plunger shaft slides and fits inside the plunger sleeve, thereby increasing the protection of the equipment during use.

[0015] As a preferred technical solution of this utility model, the top of the oil outlet valve is provided with a top block, the top of the first buffer spring is connected and fixed to the connecting cap, and the bottom of the plunger sleeve is provided with a sealing ring.

[0016] The above technical solution enables the plunger sleeve to slide more stably when it is in contact with the plunger shaft, thereby increasing the stability of the equipment during use.

[0017] As a preferred technical solution of this utility model, the left end of the sealing ring is provided with an oil injection hole, and the inner side of the sealing ring is provided with a tight-fitting ring.

[0018] The above technical solution enables the equipment to drain oil through the oil injection hole during oil draining, thereby increasing the stability of the equipment during use.

[0019] As a preferred embodiment of this utility model, the outer side of the plunger shaft is in close contact with the sealing ring, and the top of the second buffer spring is fixedly connected to the sealing ring.

[0020] The above technical solution enables the bottom of the plunger shaft to be sealed and limited by a tight-fitting ring when it is slidingly connected with the inside of the plunger sleeve, thereby increasing the sealing performance of the equipment during operation.

[0021] Compared with the prior art, the beneficial effects of this utility model are: by setting the piston mechanism, after the oil inlet groove transmits the oil to the inside of the connecting cap and the plunger sleeve, the oil outlet valve and the plunger shaft will descend, so that after the oil is transmitted to the oil filling hole for discharge, the first buffer spring will drive the oil outlet valve to reset, and the second buffer spring will also drive the plunger shaft to reset, thus making the device more convenient to reset;

[0022] Furthermore, the use of connecting bolts makes the top of the connecting cap more stable when it is fixedly connected to other equipment, thereby increasing the stability of the equipment during installation.

[0023] Furthermore, by setting a tight-fitting ring inside the sealing ring, the bottom of the plunger shaft can be sealed and limited by the tight-fitting ring when it slides with the plunger sleeve, thereby increasing the sealing performance of the device during operation. Attached Figure Description

[0024] Figure 1 This is a front view elevation diagram of the present utility model;

[0025] Figure 2 This is a schematic diagram of the layered structure of the front elevation of this utility model;

[0026] Figure 3 This is a three-dimensional structural schematic diagram of the plunger sleeve of this utility model, showing a frontal cross-section.

[0027] Figure 4 This is a schematic diagram of the layered three-dimensional structure of the plunger sleeve of this utility model.

[0028] Figure 5 This is a three-dimensional structural diagram of the plunger shaft of this utility model.

[0029] In the diagram: 1. Connecting cap; 2. Oil inlet groove; 3. Connecting bolt; 4. Connecting cavity; 5. Plunger sleeve; 6. Sealing groove; 7. Wear-resistant ring; 8. Sealing ring; 9. Oil injection hole; 10. Sealing ring; 11. First buffer spring; 12. Oil outlet valve; 13. Top block; 14. Plunger shaft; 15. Fitting pad; 16. Second buffer spring; 17. Buffer base. Detailed Implementation

[0030] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0031] To address the issue in existing fuel injection pump plunger assemblies where the piston mechanism is difficult to reset, potentially leading to oil leakage during operation, the following solution is disclosed. Please refer to [link / reference]. Figures 1-5 This utility model provides a technical solution: a plunger assembly for a marine diesel engine fuel injection pump, including a connecting cap 1 and a plunger sleeve 5 installed at the bottom of the connecting cap 1, wherein the top of the connecting cap 1 is provided with an oil inlet groove 2;

[0032] The connecting cap 1 has a connecting cavity 4 inside, and the plunger sleeve 5 has a piston mechanism inside. The piston mechanism includes an oil outlet valve 12. The top of the oil outlet valve 12 is connected to a first buffer spring 11. The plunger sleeve 5 has a plunger shaft 14 inside, and the top of the plunger shaft 14 has a fitting pad 15. The top of the fitting pad 15 fits against the oil outlet valve 12. The bottom of the plunger shaft 14 has a second buffer spring 16, and the bottom of the second buffer spring 16 is equipped with a buffer base 17.

[0033] The top of the connecting cap 1 is provided with a connecting bolt 3, and the connecting cap 1 is fixedly connected to other equipment through the connecting bolt 3. The outer side of the plunger sleeve 5 is provided with a sealing groove 6, and the plunger sleeve 5 is sealed to the bottom of the connecting cap 1 through the sealing groove 6.

[0034] The plunger sleeve 5 is provided with a wear-resistant ring 7 inside, and the inner side of the wear-resistant ring 7 is slidably connected to the plunger shaft 14, and the inner side of the wear-resistant ring 7 is slidably connected to the oil outlet valve 12. The top of the oil outlet valve 12 is provided with a top block 13, and the top of the first buffer spring 11 is connected and fixed to the connecting cap 1. The bottom of the plunger sleeve 5 is provided with a sealing ring 8.

[0035] The sealing ring 8 has an oil injection hole 9 at the left end, and a tight-fitting ring 10 is provided on the inner side of the sealing ring 8. The outer side of the plunger shaft 14 is in close contact with the tight-fitting ring 10, and the top of the second buffer spring 16 is fixedly connected to the sealing ring 8.

[0036] Working principle: When using the marine diesel engine fuel injection pump plunger assembly, firstly, the connecting cap 1 and the plunger sleeve 5 are sealed and fixedly connected. Then, the fuel is transmitted to the connecting cavity 4 through the oil inlet groove 2. At the same time, due to the pressure of the fuel, the oil outlet valve 12 will drop, causing the first buffer spring 11 to extend. Simultaneously, the plunger shaft 14 will also drop, causing the second buffer spring 16 to contract. The fuel will then be discharged through the oil outlet hole. When the fuel is discharged, the oil outlet valve 12 will reset under the action of the first buffer spring 11, thereby blocking the oil inlet groove 2 by the top block 13 at the top of the oil outlet valve 12.

[0037] When the plunger shaft 14 slides inside the plunger sleeve 5, the sealing ring 10 inside the sealing ring 8 will fit against the outside of the plunger shaft 14, so that the plunger shaft 14 will not leak oil when sliding. The buffer base 17 will also fix the bottom of the second buffer spring 16. When the oil is discharged, it can be discharged through the oil injection hole 9 as the oil outlet, so that the equipment can be more stable during the oil pumping process.

[0038] This completes a series of tasks. The contents not described in detail in this specification are existing technologies known to those skilled in the art.

[0039] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A plunger assembly for a marine diesel engine fuel injection pump, comprising a connecting cap (1) and a plunger sleeve (5) installed at the bottom of the connecting cap (1), wherein the top of the connecting cap (1) is provided with an oil inlet groove (2); Its features are: The connecting cap (1) has a connecting cavity (4) inside, and the plunger sleeve (5) has a piston mechanism inside, and the piston mechanism includes an oil outlet valve (12). The top of the oil outlet valve (12) is connected to a first buffer spring (11), and the plunger sleeve (5) has a plunger shaft (14) inside, and the top of the plunger shaft (14) has a fitting pad (15). The top of the fitting pad (15) fits against the oil outlet valve (12), and the bottom of the plunger shaft (14) has a second buffer spring (16), and the bottom of the second buffer spring (16) is equipped with a buffer base (17).

2. The marine diesel engine fuel injection pump plunger assembly according to claim 1, characterized in that, The top of the connecting cap (1) is provided with a connecting bolt (3), and the connecting cap (1) is fixedly connected to other equipment through the connecting bolt (3).

3. The marine diesel engine fuel injection pump plunger assembly according to claim 2, characterized in that, The plunger sleeve (5) is provided with a sealing groove (6) on the outside, and the plunger sleeve (5) is sealed to the bottom of the connecting cap (1) through the sealing groove (6).

4. The marine diesel engine fuel injection pump plunger assembly according to claim 3, characterized in that, The plunger sleeve (5) is provided with a wear-resistant ring (7) inside, and the inner side of the wear-resistant ring (7) is slidably connected to the plunger shaft (14), and the inner side of the wear-resistant ring (7) is slidably connected to the oil outlet valve (12).

5. The marine diesel engine fuel injection pump plunger assembly according to claim 4, characterized in that, The oil outlet valve (12) is provided with a top block (13) at the top, and the top of the first buffer spring (11) is connected and fixed to the connecting cap (1), and the bottom of the plunger sleeve (5) is provided with a sealing ring (8).

6. The marine diesel engine fuel injection pump plunger assembly according to claim 5, characterized in that, The sealing ring (8) has an oil injection hole (9) at its left end, and a tight-fitting ring (10) is provided on the inner side of the sealing ring (8).

7. The marine diesel engine fuel injection pump plunger assembly according to claim 6, characterized in that, The outer side of the plunger shaft (14) is in close contact with the sealing ring (10), and the top of the second buffer spring (16) is fixedly connected to the sealing ring (8).

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