Camshaft forced lubrication structure and oil injection system
By designing a forced lubrication structure on the camshaft of the high-pressure oil supply pump, the main oil passage and the secondary oil passage are used to guide the pressure oil to key components, the problem of failure of lubrication performance in the high-pressure oil supply pump is solved, effective lubrication and cooling of the camshaft and other key components is achieved, and the service life of the equipment is extended.
Patent Information
- Application Number
- CN202421805303.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-29
- Publication Date
- 2025-06-24
- Estimated Expiration
- 2034-07-29
AI Technical Summary
In high-pressure oil supply pumps, the camshaft and other key pressure-bearing components bear alternating loads during the high-pressure oil supply process, resulting in failure of lubricating performance, which in turn leads to intensified wear between mechanisms and failure of the high-pressure oil supply pump function.
A forced lubrication structure of camshaft is designed, and lubrication and cooling of these parts is achieved by setting an oil cavity and an oil inlet on the camshaft, and guiding the pressure oil to the mating and connecting parts that produce relative movement with the camshaft through the main oil passage and the secondary oil passage.
It effectively prevents wear of the camshaft and other key components, maintains the stable oil supply function of the high-pressure oil supply pump, and extends the service life of the equipment.
Smart Images
Figure CN223018700U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of fuel injection systems, in particular to a camshaft forced lubrication structure and a fuel injection system. Background Art
[0002] As all the oil supply mechanisms in the high-pressure common rail system, the high-pressure fuel supply pump continuously supplies oil to the high-pressure common rail system according to the actual working conditions of the engine, ensuring the oil supply pressure and oil supply flow inside the common rail system, and ensuring the stability of the oil supply pressure and oil supply flow. During the high-pressure fuel supply process, key pressure-bearing components such as the camshaft, bearings, and camshaft sleeves are subjected to alternating loads at multiple parts, and their working environment is very harsh. Once the lubrication performance of the key contact parts inside the high-pressure fuel supply pump fails, it will directly lead to increased wear between the mechanisms, and then lead to the failure of the oil supply function of the high-pressure fuel supply pump. Summary of the Utility Model
[0003] Aiming at the deficiencies in the prior art, the first object of the utility model is to provide a camshaft forced lubrication structure, which can not only lubricate and cool the mating parts that rotate relative to the camshaft, but also lubricate and cool the fuel transfer pump shaft and its connecting parts.
[0004] To achieve the above object, the utility model adopts the following technical solutions:
[0005] A camshaft forced lubrication structure and a fuel injection system, comprising: a camshaft connected to a fuel transfer pump shaft through a connecting part, the camshaft having an oil cavity and an oil inlet communicating with the oil cavity, the camshaft having a main oil passage communicating the oil cavity and a mating part that moves relative to the camshaft; the camshaft having a secondary oil passage communicating the oil cavity with the connecting part.
[0006] Compared with the prior art, the utility model has the following beneficial effects:
[0007] During operation, external force causes pressure oil to enter the oil cavity of the camshaft from the oil inlet, and the pressure oil enters the mating clearance of the mating part that moves relative to the camshaft through the main oil passage, realizing lubrication and cooling of this part. Another part of the pressure oil enters the connecting part through the secondary oil passage, playing a role in lubricating and cooling the connecting part, the camshaft and the fuel transfer pump shaft.
[0008] As a preferred solution, the diameter of the secondary oil passage is less than or equal to that of the main oil passage.
[0009] As a preferred solution, at least one end of the camshaft penetrates axially, and a damping plug is installed at this end, and holes are processed on the damping plug to form the secondary oil passage.
[0010] As a preferred solution, the extension path of the secondary oil passage has a narrow flow area.
[0011] As a preferred solution, an annular protrusion is provided on the damping plug, and the narrow flow area is formed by the protrusion and the inner wall of the camshaft.
[0012] As a preferred solution, both ends of the camshaft penetrate axially along its axis, and a plug is provided at one end of the camshaft facing away from the damping plug.
[0013] As a preferred solution, the fitting includes a retaining ring and / or a sliding sleeve and / or a sliding bearing.
[0014] The second object of the present invention is to provide an injection system which can not only lubricate and cool the fitting that rotates relative to the camshaft, but also lubricate and cool the fuel transfer pump shaft and its connecting parts.
[0015] To achieve the above object, the present invention adopts the following technical solutions:
[0016] An injection system includes the camshaft forced lubrication structure described in any one of the above. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 It is a schematic cross-sectional structure diagram of the lubrication structure;
[0018] Figure 2 For Figure 1 The partial enlarged view at A in
[0019] In the above drawings:
[0020] 1. Camshaft; 2. Fuel transfer pump shaft; 3. Oil cavity; 4. Connecting part; 5. Oil inlet; 6. Retaining ring; 7. Sliding sleeve; 8. Sliding bearing; 9. Main oil passage; 10. Secondary oil passage; 11. Damping plug; 12. Protrusion; 13. Plug. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0021] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments; the structures described in various embodiments can be freely combined without conflict in terms of structure or principle.
[0022] In the present utility model, unless otherwise clearly defined and limited, terms such as "installation", "connection", "attachment", "fixation", etc. shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral one; it may be a mechanical connection or an electrical connection; it may be a direct connection or an indirect connection through an intermediate medium, and it may be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.
[0023] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by terms such as "center", "upper", "lower", "left", "right", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of this utility model is usually placed during use. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present utility model. In addition, terms such as "first", "second", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.
[0024] The following describes some embodiments of the present utility model with reference to the drawings:
[0025] In the prior art, when the high-pressure fuel supply pump is working, the camshaft 1 at the pressure-bearing support part rotates relative to the mating parts and bears alternating loads. If lubrication cannot be timely and sufficient, it will lead to an increase in the friction force between the mating parts, resulting in wear and deformation, and the local temperature will rise, reducing the viscosity of the pressure oil and affecting the lubrication effect. When the poor lubrication continues to deteriorate, it will affect the service life of the high-pressure fuel supply pump and ultimately cause the high-pressure fuel supply pump to fail.
[0026] To solve this problem, as Figure 1 shown, the present utility model proposes a forced lubrication structure for the camshaft, including: a camshaft 1. The left end of the camshaft 1 is connected to an oil transfer pump shaft 2 through a connecting member 4. The camshaft 1 has an oil cavity 3 extending along its axial direction. The right end of the oil cavity 3 is provided with an oil inlet 5 communicating with it. A mating part that rotates relative to the camshaft 1 during operation is installed on the camshaft 1. The camshaft 1 and the mating part are connected through a main oil passage 9. The main oil passage 9 is specifically divided into multiple oil holes, and each oil hole corresponds to the mating part. The main oil passage 9 serves to guide the pressure oil in the oil cavity 3 to the mating clearance between the camshaft 1 and the mating part.
[0027] The types and quantities of the mating parts can be selected and designed according to actual requirements. Exemplarily, the mating parts include a retaining ring 6, a sliding sleeve 7, and / or a sliding bearing 8, etc. Among them, taking the retaining ring 6 as an example, the retaining ring 6 is installed at the left and right supports of the camshaft 1 and forms an integral body with the camshaft 1; communication oil holes are provided on the retaining ring 6 and the camshaft 1, and pressure oil enters the mating clearance between the sliding bearing 8 and the camshaft 1 through this hole to lubricate the sliding bearing 8. In this structure, the oil holes provided at each pressure-bearing support of the camshaft 1, the oil cavity 3 of the camshaft 1, the retaining ring 6, the sliding bearing 8, and the sliding sleeve 7 together form a lubrication system for the camshaft 1, and lubricate the rotating pairs between the camshaft 1 and the sliding bearing 8, and between the camshaft 1 and the sliding bearing 8.
[0028] Combined Figure 2 As shown, the camshaft 1 also has a secondary oil passage 10, and the secondary oil passage 10 connects the oil cavity 3 with the connecting part 4, playing a role in guiding the pressure oil.
[0029] During operation, an external force causes the pressure oil to enter the oil cavity 3 of the camshaft 1 from the oil inlet 5, and the pressure oil enters the mating clearance of the mating parts that move relative to the camshaft 1 through the main oil passage 9 to achieve lubrication and cooling of this part. Another part of the pressure oil flows along Figure 2 the arrow direction of to enter the connecting part 4 through the secondary oil passage 10, playing a role in lubricating and cooling the connecting part 4, the camshaft 1, and the fuel transfer pump shaft 2.
[0030] As a preferred solution, as Figure 2 shown, the diameter of the secondary oil passage 10 is designed to be less than or equal to that of the main oil passage 9. In this way, not only the pressure in the oil cavity 3 is ensured to be stable, but also the pressure oil plays a role in lubricating and cooling the connection part of the camshaft 1, the connecting part 4, and the fuel transfer pump shaft 2.
[0031] As a preferred solution, as Figure 1 shown, the oil cavity 3 is designed as a through hole that penetrates from left to right, which is more convenient in processing and more feasible in technology. At the same time, the through hole is beneficial for cleaning and is more advantageous in ensuring the cleanliness of the product. In order to ensure the pressure in the oil cavity 3, plug caps 13 are also designed at the left and right ends of the through hole.
[0032] As a preferred solution, as Figure 1 and Figure 2 shown, one of the plug caps 13 is designed as a damping plug 11 and is press-fitted at the left end of the oil cavity 3. The damping plug 11 is processed with holes to form the secondary oil passage 10. Part of the pressure oil flows through the damping plug 11 to the connection part of the camshaft 1, the connecting part 4, and the fuel transfer pump shaft 2; during this process, the damping plug 11 can slow down the flow rate of the pressure oil and reduce the flow rate of the pressure oil, so that a small amount of the pressure oil in the oil cavity 3 flows out through the damping holes, which is beneficial for stabilizing the pressure in the oil cavity 3.
[0033] As a preferred solution, asFigure 1 and Figure 2 As shown in Figure 2 , the extension path of the secondary oil passage 10 has a narrow flow area. Exemplarily, an annular protrusion 12 is provided on the damping plug 11, and the protrusion 12 and the inner wall of the camshaft 1 enclose a narrow flow area. The narrow flow area can reduce the flow rate of the pressurized oil flowing out of the secondary oil passage 10.
[0034] The present utility model further provides an injection system, including the camshaft forced lubrication structure described in any one of the above. It can not only lubricate and cool the mating parts that rotate relative to the camshaft 1, but also lubricate and cool the fuel transfer pump shaft 2 and its connecting parts 4. The pressurized oil entering the lubrication system has a certain pressure, which belongs to forced lubrication for the entire lubrication system, and can also take away the heat at the friction part in time through the oil pressure difference, and has a better lubrication and cooling effect between each rotating pair. In addition, this structure can make the lubrication of the pressure-bearing support mating part more sufficient, and is simpler in processing, and is more advantageous in terms of practicability and processability.
Claims
1. A camshaft forced lubrication structure, characterized in that: include: A camshaft (1) connected to an oil pump shaft (2) via a connecting piece (4), the camshaft (1) having an oil chamber (3) and an oil inlet (5) connected to the oil chamber (3), the camshaft (1) having a main oil passage (9) connecting the oil chamber (3) and a matching piece that generates relative motion with the camshaft (1); and the camshaft (1) having a secondary oil passage (10) connecting the oil chamber (3) and the connecting piece (4).
2. A camshaft forced lubrication structure according to claim 1, characterized in that: The diameter of the secondary oil passage (10) is smaller than or equal to the main oil passage (9).
3. A camshaft forced lubrication structure according to claim 2, characterized in that: At least one end of the camshaft (1) is penetrated along its axial direction, and a damping plug (11) is installed on the end, and a hole is processed on the damping plug (11) to form the secondary oil channel (10).
4. A camshaft forced lubrication structure according to claim 3, characterized in that: The extension path of the secondary oil passage (10) has a narrow flow area.
5. The camshaft forced lubrication structure according to claim 4, characterized in that: The damping plug (11) is provided with an annular protrusion (12), and the protrusion (12) and the inner wall of the camshaft (1) form the narrow flow area.
6. A camshaft forced lubrication structure according to any one of claims 3 to 5, characterized in that: Both ends of the camshaft (1) are connected in the axial direction thereof, and a blocking cover (13) is provided at one end of the camshaft (1) away from the damping plug (11).
7. A camshaft forced lubrication structure according to any one of claims 1 to 5, characterized in that: The matching parts include a retaining ring (6) and / or a sliding sleeve (7) and / or a sliding bearing (8).
8. A fuel injection system, characterized in that: It comprises the camshaft forced lubrication structure according to any one of claims 1 to 7.