A positioning pin structure of an oil injection pump

Abstract

The application discloses a kind of oil injection pump positioning pin structures, belong to engine diesel engine technical field, this kind of oil injection pump positioning pin structure, including driving shaft, the driving shaft taper surface is provided with taper pin hole, the bottom end of the taper pin hole is slidably connected with fixed base, the top end of the fixed base is slidably connected with taper column, the top end of the taper column is rotatably connected with hollow column, the top end of the hollow column is installed with top cover.The application is changed into coil spring by half round key, the solid structure of half round key is changed into hollow structure, so that positioning pin is assembled, coil spring is deformed, pin hole is not deformed, pin hole is greatly reduced, and simultaneously, fixed base is provided with pressing locking structure inside, when the taper surface of driving shaft is pressed and adhered, it will press locking structure, ensure the close cooperation of taper pin hole and positioning pin, to improve the adhesion of taper surface, ensure the high-precision adhesion of taper surface, eliminate the influence of positioning pin on taper surface precision, improve product reliability.

Description

Technical Field

[0001] This invention belongs to the technical field of fuel supply systems, and specifically relates to a fuel injection pump positioning pin structure. Background Technology

[0002] The fuel injection pump is a crucial component of a diesel engine. The fuel injection pump assembly typically consists of the pump itself, a governor, and other components mounted together. The governor ensures low-speed operation and limits the maximum engine speed, maintaining a specific relationship between the injection quantity and the engine speed. The fuel injection pump, on the other hand, is the most critical component, considered the "heart" of the diesel engine. Powered by a drive shaft connected to a gear train via a conical surface, the pump compresses the plunger, converting low-pressure fuel into high-pressure fuel. The locating pin design on the drive shaft reduces the stress on the gear train, minimizing pump noise and improving product reliability.

[0003] Currently, the upper locating pin structure of the drive shaft tapered surface is a semi-circular key structure, which is interference-fitted with the pin hole on the drive shaft. However, the drive shaft transmits power by pressing the tapered surface together, which requires high precision. When assembling the semi-circular key, because it is an interference fit and the semi-circular key is a solid structure, the tapered surface is deformed. After assembly, the accuracy of the tapered surface is reduced, and even the contact area is reduced, affecting the product function. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a fuel injection pump positioning pin structure.

[0005] The technical solution adopted to solve the above technical problems is: a fuel injection pump positioning pin structure, including a drive shaft, a tapered pin hole provided on the tapered surface of the drive shaft, a fixed base slidably connected to the bottom end of the tapered pin hole, a tapered column slidably connected to the top end of the fixed base, a hollow column rotatably connected to the top end of the tapered column, and a top cover installed on the top end of the hollow column.

[0006] Furthermore, the fixed base is a cylindrical concave structure, and the outer side of the fixed base is provided with a slot, which is arranged in a circumferential array. A pressure column is slidably connected through the bottom of the inner side of the fixed base. The top of the pressure column is concave, and the concave end of the pressure column engages with the conical end of the conical column. Several L-shaped plates are provided on the cylindrical surface of the pressure column, which are arranged in a circumferential array.

[0007] Through the above technical solution, the fixed base moves by pressing down the pressure column, thereby driving the locking structure to achieve a tight fit between the tapered pin hole and the drive shaft, further improving the contact force of the tapered surface, ensuring high-precision contact of the tapered surface, reducing tapered surface deformation, thereby improving the reliability of the fuel injection pump and reducing noise.

[0008] Furthermore, a square card plate is slidably connected to the middle of the L-shaped plate, and a rotating seat is rotatably connected to the end of the square card plate near the fixed base. The rotating seat is fixedly connected to the fixed base, and the end of the square card plate away from the rotating seat is slidably connected to the slot. A rubber head is fixedly connected to the end of the square card plate located inside the slot.

[0009] With the above technical solution, when the pressure column moves downward, one end of the square clamping plate is installed inside the fixed base through the rotating seat. The middle part of the L-shaped plate presses down on the square clamping plate, causing the other end of the square clamping plate to rotate and extend out of the slot to contact the surface of the tapered pin hole. The rubber head is tightly fitted with the surface of the tapered pin hole, thereby achieving a more precise fit between the tapered pin hole and the drive shaft. The elasticity of the rubber head can absorb some vibration, further reducing noise and improving the stability and service life of the fuel injection pump.

[0010] Furthermore, a trapezoidal push block is fixedly connected to the end of the L-shaped plate away from the pressure column, a top block is slidably connected to one side of the trapezoidal push block, a curved plate is fixedly connected to the end of the top block away from the trapezoidal push block, the curved plate is slidably connected to the inner surface of the fixed base, a sliding column is fixedly connected to both sides of the end of the curved plate where the top block is installed, the sliding column is slidably connected to the fixed base, and a limit plate is fixedly connected to the end of the sliding column inside the fixed base.

[0011] Through the above technical solution, when the pressure column moves downward, the trapezoidal push block cooperates with the top block to push the four curved plate plates inward and apply uniform pressure to the surface of the conical column, ensuring a tight fit between the conical column and the conical pin hole. The curved surface design of the plate plates makes the applied pressure more uniform, avoiding local stress concentration, thereby improving the stability and reliability of the overall structure. The cooperation between the sliding column and the limiting plate ensures the positioning accuracy of the curved plate plates during the sliding process and prevents structural damage caused by excessive pressure.

[0012] Furthermore, the top end of the conical column is slidably fitted with the bottom end of the hollow column, the top end of the conical column is rotatably connected to a rotating shaft, the end of the rotating shaft is fixedly connected to a cross slide plate, and the inner wall of the hollow column is fixedly connected to several sliding grooves, the sliding grooves are arranged in a circumferential array, and the sliding grooves engage and slide with the cross slide plate.

[0013] Through the above technical solution, the conical column can rotate freely with the hollow column through the rotating shaft and the cross slide plate. The circumferential array arrangement of the slide groove can ensure the stable positioning of the cross slide plate in the slide groove, further improving the flexibility and accuracy of the positioning pin structure.

[0014] Furthermore, a slot is fixedly connected to the top of the slide, a fixing plate is provided inside the slot, the top of the fixing plate is fixedly connected to the inside of the top cover, and a coiled spring is provided at the bottom of the top cover, with the bottom of the coiled spring rotatably connected to the cross slide plate.

[0015] Through the above technical solution, the presence of the coiled spring provides a certain elastic support for the cross slide, enabling it to maintain a certain rebound force when subjected to external force, thereby ensuring the stability and reliability of the fuel injection pump positioning pin structure during operation.

[0016] The beneficial effects of this invention are as follows:

[0017] 1. This invention transforms the semicircular key into a coiled spring and the solid structure of the semicircular key into a hollow structure. During assembly, the coiled spring pin deforms while the pin hole remains undeformed, greatly reducing the force on the pin hole. This eliminates the impact of the positioning pin on the accuracy of the conical surface and improves product reliability.

[0018] 2. This invention provides a pressing and locking structure inside the fixed base. When the tapered surface of the drive shaft is pressed and fitted, the pressing and locking structure is activated to ensure a tight fit between the tapered pin hole and the positioning pin. This improves the fitting force of the tapered surface, ensures high-precision fitting of the tapered surface, reduces tapered surface deformation, and thus improves the reliability of the fuel injection pump and reduces noise.

[0019] 3. This invention provides a groove on the outside of the fixed base and installs a rubber head with elastic properties in the groove, which makes the fit between the tapered pin hole and the drive shaft more precise. At the same time, the elastic properties of the rubber head can absorb some vibration, further reduce noise, and improve the stability and service life of the fuel injection pump.

[0020] 4. This invention uses a combination of trapezoidal push blocks and curved plate to ensure a tight fit between the conical column and the conical pin hole. The curved design of the curved plate makes the applied pressure more uniform, avoids local stress concentration, and thus improves the stability and reliability of the overall structure. Attached Figure Description

[0021] Figure 1 This is a cross-sectional schematic diagram of the drive shaft of the present invention;

[0022] Figure 2 This is a schematic diagram of the fuel injection pump positioning pin structure of the present invention;

[0023] Figure 3 This is a first cross-sectional view of the fixed base of the present invention;

[0024] Figure 4 This is a second cross-sectional view of the fixed base of the present invention;

[0025] Figure 5 This is a third sectional view of the fixed base of the present invention;

[0026] Figure 6 This is a schematic diagram of the conical column structure of the present invention;

[0027] Figure 7 This is a cross-sectional schematic diagram of the hollow column of the present invention;

[0028] Figure 8 This is a top view of the hollow column of the present invention.

[0029] Reference numerals: 1. Drive shaft; 2. Tapered pin hole; 3. Fixed base; 4. Tapered column; 5. Hollow column; 6. Top cover; 7. Pressure column; 8. L-shaped plate; 9. Square clamping plate; 10. Rotating seat; 11. Slot; 12. Rubber head; 13. Trapezoidal push block; 14. Top block; 15. Curved clamping plate; 16. Limiting plate; 17. Sliding column; 18. Rotating shaft; 19. Cross slide plate; 20. Slide groove; 21. Slot; 22. Fixed plate; 23. Coil spring. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0031] like Figures 1 to 8 As shown, a positioning pin structure for an injection pump in this embodiment includes a drive shaft 1. The drive shaft 1 has a tapered pin hole 2 on its tapered surface. A fixed base 3 is slidably connected to the bottom end of the tapered pin hole 2. A tapered column 4 is slidably connected to the top end of the fixed base 3. A hollow column 5 is rotatably connected to the top end of the tapered column 4. A top cover 6 is installed on the top end of the hollow column 5. The semi-circular key is changed into a coiled spring 23, and the solid structure of the semi-circular key is changed into a hollow structure. When the positioning pin is assembled, the coiled spring 23 deforms, but the pin hole does not deform, and the force on the pin hole is greatly reduced.

[0032] The fixed base 3 has a cylindrical concave structure. The outer side of the fixed base 3 is provided with a slot 11, which is arranged in a circumferential array. The bottom of the inner side of the fixed base 3 is slidably connected to a pressure column 7. The top of the pressure column 7 is concave, and the concave end of the pressure column 7 engages with the conical end of the conical column 4. Several L-shaped plates 8 are provided on the cylindrical surface of the pressure column 7, which are arranged in a circumferential array. The fixed base 3 moves by pressing down the pressure column 7, thereby driving the locking structure to achieve a tight fit between the conical pin hole 2 and the drive shaft 1, further improving the contact strength of the conical surface.

[0033] A square clamping plate 9 is slidably connected to the middle of the L-shaped plate 8. A rotating seat 10 is rotatably connected to one end of the square clamping plate 9 near the fixed base 3. The rotating seat 10 is fixedly connected to the fixed base 3. The end of the square clamping plate 9 away from the rotating seat 10 is slidably connected to the slot 11. A rubber head 12 is fixedly connected to one end of the square clamping plate 9 inside the slot 11. The rubber head 12 fits tightly against the surface of the tapered pin hole 2, thereby achieving a more precise fit between the tapered pin hole 2 and the drive shaft 1. The elasticity of the rubber head 12 can absorb some vibration, further reduce noise, and improve the stability and service life of the fuel injection pump.

[0034] A trapezoidal push block 13 is fixedly connected to the end of the L-shaped plate 8 away from the pressure column 7. A top block 14 is slidably connected to one side of the trapezoidal push block 13. A curved plate 15 is fixedly connected to the end of the top block 14 away from the trapezoidal push block 13. The curved plate 15 is slidably connected to the inner surface of the fixed base 3. Through the cooperation of the trapezoidal push block 13 and the top block 14, the four curved plates 15 are pushed inward and evenly press on the surface of the conical column 4 to ensure a tight fit between the conical column 4 and the conical pin hole 2. Sliding columns 17 are fixedly connected to both sides of the curved plate 15 where the top block 14 is installed. The sliding columns 17 are slidably connected to the fixed base 3. A limit plate 16 is fixedly connected to the end of the sliding column 17 inside the fixed base 3. The cooperation between the sliding column 17 and the limit plate 16 ensures the positioning accuracy of the curved plate 15 during the sliding process and prevents structural damage caused by excessive pressure.

[0035] The top of the conical column 4 slides and engages with the bottom of the hollow column 5. A rotating shaft 18 is rotatably connected through the top of the conical column 4. A cross slide plate 19 is fixedly connected through the end of the rotating shaft 18. The conical column 4 and the hollow column 5 can rotate freely through the rotating shaft 18 and the cross slide plate 19. Several sliding grooves 20 are fixedly connected to the inner wall of the hollow column 5. The sliding grooves 20 are arranged in a circumferential array. The sliding grooves 20 engage and slide with the cross slide plate 19, which can ensure the stable positioning of the cross slide plate 19 in the sliding grooves 20, and further improve the flexibility and accuracy of the positioning pin structure.

[0036] The top of the slide 20 is fixedly connected to the slot 21, and the inside of the slot 21 is provided with a fixing plate 22. The top of the fixing plate 22 is fixedly connected to the inside of the top cover 6. The bottom of the top cover 6 is provided with a coil spring 23, and the bottom of the coil spring 23 is rotatably connected to the cross slide plate 19. The presence of the coil spring 23 provides a certain elastic support for the cross slide plate 19, so that it can maintain a certain rebound force when subjected to external force, thereby ensuring the stability and reliability of the fuel injection pump positioning pin structure during operation.

[0037] The working principle of this embodiment is as follows:

[0038] During operation, the drive shaft 1 achieves precise contact between the tapered pin hole 2 and the tapered column 4 through a tight fit. The tapered column 4 is connected to the cross slide plate 19 via a rotating shaft 18. The cross slide plate 19 slides within the groove 20, ensuring the flexibility and accuracy of the positioning pin structure. When the drive shaft 1 rotates, the pressure between the tapered pin hole 2 and the tapered column 4 is transmitted to the L-shaped plate 8 through the pressure column 7, causing the L-shaped plate 8 to slide within the slot 11. The sliding connection between the square clamping plate 9 and the L-shaped plate 8 allows it to be adjusted according to the tapered shape of the tapered pin hole 2, thereby ensuring a tight fit between the tapered pin hole 2 and the tapered column 4. The rubber head 12, located at one end inside the slot 11, can absorb some vibration, reduce noise, and improve the stability and service life of the fuel injection pump. Meanwhile, the elastic properties of the rubber head 12 ensure a more precise fit between the tapered pin hole 2 and the drive shaft 1. The combination of the trapezoidal push block 13 and the curved plate 15 ensures a tight fit between the tapered column 4 and the tapered pin hole 2. The curved surface design of the curved plate 15 makes the applied pressure more uniform, avoiding local stress concentration, thereby improving the stability and reliability of the overall structure. The presence of the coil spring 23 provides a certain elastic support for the cross slide plate 19, enabling it to maintain a certain rebound force when subjected to external force, thereby ensuring the stability and reliability of the fuel injection pump positioning pin structure during operation. This invention not only improves the performance of the fuel injection pump but also reduces noise and extends its service life, demonstrating significant practical value.

[0039] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention.

Claims

1. A fuel injection pump positioning pin structure, comprising a drive shaft (1), characterized in that: The drive shaft (1) has a tapered pin hole (2) on its tapered surface. A fixed base (3) is slidably connected to the bottom end of the tapered pin hole (2). A tapered column (4) is slidably connected to the top end of the fixed base (3). A hollow column (5) is rotatably connected to the top end of the tapered column (4). A top cover (6) is installed on the top end of the hollow column (5). The fixed base (3) is a cylindrical concave structure. The fixed base (3) has a slot (11) on its outer side. The slot (11) is arranged in a circular array. The bottom of the fixed base (3) is slidably connected to a pressure column (7). The top of the pressure column (7) is concave. The concave end of the pressure column (7) meshes with the conical end of the conical column (4). The cylindrical surface of the pressure column (7) is provided with several L-shaped plates (8). The L-shaped plates (8) are arranged in a circular array. A square card plate (9) is slidably connected to the middle of the L-shaped plate (8). A rotating seat (10) is rotatably connected to one end of the square card plate (9) near the fixed base (3). The rotating seat (10) is fixedly connected to the fixed base (3). The end of the square card plate (9) away from the rotating seat (10) is slidably connected to the slot (11). A rubber head (12) is fixedly connected to one end of the square card plate (9) inside the slot (11). The L-shaped plate (8) is fixedly connected to a trapezoidal push block (13) at the end away from the pressure column (7). A top block (14) is slidably connected to one side of the trapezoidal push block (13). A curved plate (15) is fixedly connected to the end of the top block (14) away from the trapezoidal push block (13). The curved plate (15) is slidably connected to the inner surface of the fixed base (3). A sliding column (17) is fixedly connected to both sides of one end of the curved plate (15) where the top block (14) is installed. The sliding column (17) is slidably connected to the fixed base (3). A limit plate (16) is fixedly connected to one end of the sliding column (17) inside the fixed base (3). The top of the conical column (4) is slidably fitted with the bottom of the hollow column (5). A rotating shaft (18) is rotatably connected through the top of the conical column (4). A cross slide plate (19) is fixedly connected through the end of the rotating shaft (18). Several sliding grooves (20) are fixedly connected to the inner wall of the hollow column (5). The sliding grooves (20) are arranged in a circumferential array. The sliding grooves (20) engage and slide with the cross slide plate (19). The top of the slide (20) is fixedly connected to a slot (21), and a fixing plate (22) is provided inside the slot (21). The top of the fixing plate (22) is fixedly connected to the inside of the top cover (6). A coiled spring (23) is provided at the bottom of the top cover (6), and the bottom of the coiled spring (23) is rotatably connected to the cross slide plate (19).

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