Pretightening force self-adaptive mechanism for conical surface sealing of diesel injector

Abstract

The invention discloses a pre-tightening force self-adaptive mechanism for conical surface sealing of a diesel injector, and relates to the technical field of diesel injectors. The needle valve comprises a needle valve body, a first needle valve guide column is fixedly connected to the inner wall of the needle valve body, a pressure-bearing conical block is fixedly connected to the bottom of the first needle valve guide column, a second needle valve guide column is fixedly connected to the bottom of the pressure-bearing conical block, and a sealing conical block is fixedly connected to the bottom of the second needle valve guide column. The top of the first needle valve guide column is fixedly connected with a memory alloy pre-tightening T-shaped block, and an anti-clearance device is arranged on the inner wall of the needle valve body. Through cooperation of the memory alloy pre-tightening T-shaped block, the moving ring, the rubber sealing bag and the first spring, the gaps between the memory alloy pre-tightening T-shaped block and the needle valve body and between the memory alloy pre-tightening T-shaped block and the first needle valve guide column can be sealed through deformation of the rubber sealing bag, the problem of poor sealing of a local area is solved, and therefore the overall sealing performance is improved, and the leakage risk is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of diesel engine injectors, in particular to a pre-tightening force adaptive mechanism for a conical surface seal of a diesel engine injector. Background Art

[0002] As an important component of diesel engines, the sealing performance of diesel engine injectors directly affects the accuracy of injection and the quality of fuel atomization, thereby affecting the engine's combustion efficiency and exhaust emission levels. Traditional injector seals mostly use a mechanical pre-tightening method, providing sealing pressure through a fixed position and pre-tightening device. However, as engine operating conditions (such as temperature, pressure, and operating conditions) change, this pre-tightening force is difficult to maintain the optimal sealing state, resulting in unsatisfactory injection results, reduced fuel utilization, and increased emissions.

[0003] However, the current preload adaptive mechanism has the following problems: In the current preload adaptive mechanism, since the memory alloy preload T-shaped block can change according to the working conditions, especially when the pressure and temperature fluctuate, the change of the memory alloy preload T-shaped block will cause the gap between the memory alloy preload T-shaped block 6 and the needle valve body 1 and the needle valve guide column 1 to change, making it difficult for the memory alloy preload T-shaped block 6 to seal these gaps. Therefore, we propose a preload adaptive mechanism for the conical surface seal of the diesel engine injector. Summary of the Invention

[0004] In view of the deficiencies in the prior art, the present invention provides a preload adaptive mechanism for the conical seal of a diesel engine injector, which solves the problems raised in the above-mentioned background technology.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: a pre-tightening force adaptive mechanism for the conical surface seal of a diesel engine injector, comprising a needle valve body, the inner wall of the needle valve body is fixedly connected to a needle valve guide column 1, the bottom of the needle valve guide column 1 is fixedly connected to a pressure-bearing cone block, the bottom of the pressure-bearing cone block is fixedly connected to a needle valve guide column 2, the bottom of the needle valve guide column 2 is fixedly connected to a sealing cone block, the top of the needle valve guide column 1 is fixedly connected to a memory alloy pre-tightening T-shaped block, the inner wall of the needle valve body is provided with an anti-gap device, the anti-gap device comprises a movable ring, the outer wall of the movable ring is slidably connected to the inner wall of the needle valve body, the top of the movable ring is fixedly connected to a rubber sealing bag, and a spring is provided between the movable ring and the needle valve body. During the operation of the engine, the memory alloy of the memory alloy pre-tightening T-shaped block can sense temperature changes and adjust its shape, thereby realizing dynamic adjustment of the sealing pre-tightening force. When the memory alloy of the memory alloy pre-tightening T-shaped block is changing, the memory alloy pre-tightening T-shaped block will contact the rubber sealing bag, causing the rubber sealing bag to move downward. The downward movement of the rubber sealing bag drives the moving ring to move downward, and the downward movement of the moving ring will squeeze the spring 1. After the change of the memory alloy pre-tightening T-shaped block is completed, the spring 1 will reset by its own elastic force, and the reset of the spring 1 will push the moving ring to move upward. The upward movement of the moving ring will squeeze the rubber sealing bag. Therefore, the rubber sealing bag will be deformed due to the interaction between the moving ring and the memory alloy pre-tightening T-shaped block.

[0006] According to the above technical solution, the anti-gap device also includes two rubber strips, the bottoms of the two rubber strips are fixedly connected to the top of the rubber sealing bag, the rubber sealing bag is located on the displacement track of the memory alloy pre-tightening T-shaped block, and the two rubber strips are located on the displacement track of the memory alloy pre-tightening T-shaped block. At the same time, the rubber sealing bag will drive the rubber strip to contact the memory alloy pre-tightening T-shaped block. When the rubber strip contacts the memory alloy pre-tightening T-shaped block, it can increase friction and help the rubber sealing bag to remain stably on the bottom of the memory alloy pre-tightening T-shaped block.

[0007] According to the above technical solution, an anti-corrosion device is provided on the top of the needle valve body, and the anti-corrosion device includes a shell, and the top of the inner wall of the shell is fixedly connected to an air pressure spray bag, and the bottom of the air pressure spray bag is fixedly connected to a pressure plate, and a plurality of guide holes are opened at the bottom of the pressure plate, and the outer wall of the shell is fixedly penetrated by a liquid inlet pipe, and the end of the liquid inlet pipe away from the shell is fixedly connected to the outer wall of the air pressure spray bag, and the bottom of the pressure plate is in contact with the top of the memory alloy pre-tightening T-shaped block, and the epoxy resin coating is injected into the air pressure spray bag through the liquid inlet pipe. When the memory alloy pre-tightening T-shaped block is deformed, the upper part of the memory alloy pre-tightening T-shaped block will push the pressure plate to squeeze the air pressure spray bag. After the air pressure spray bag is squeezed, the epoxy resin coating inside the air pressure spray bag will flow to the surface of the memory alloy pre-tightening T-shaped block through the guide hole.

[0008] According to the above technical solution, a number of long grooves are provided at the bottom of the pressure plate. When the pressure plate contacts the memory alloy pre-tightening T-shaped block, the long grooves at the bottom of the pressure plate contact the memory alloy pre-tightening T-shaped block. The long grooves can help to evenly distribute the contact pressure between the pressure plate and the memory alloy pre-tightening T-shaped block.

[0009] According to the above technical solution, the outer wall of the shell is slidably connected with an arc block, a spring 2 is arranged between the arc block and the needle valve body, and a long block for pushing the arc block to move is fixed on the outer arc surface of the arc block. When the epoxy resin coating does not need to be injected, the arc block will block the liquid inlet of the liquid inlet pipe.

[0010] The present invention provides a preload adaptive mechanism for the conical seal of a diesel engine injector. It has the following beneficial effects:

[0011] (1) The present invention cooperates with the memory alloy pre-tightening T-shaped block, the moving ring, the rubber sealing bag and the spring 1, so that the moving ring moves downward and squeezes the spring 1. After the change of the memory alloy pre-tightening T-shaped block is completed, the spring 1 will reset by its own elastic force. The reset of the spring 1 will push the moving ring to move upward. The upward movement of the moving ring will squeeze the rubber sealing bag. Therefore, the rubber sealing bag will be deformed by the interaction between the moving ring and the memory alloy pre-tightening T-shaped block. Therefore, the deformation of the rubber sealing bag will seal the gap between the memory alloy pre-tightening T-shaped block and the needle valve body and the needle valve guide column 1, thereby preventing the problem of poor sealing in local areas, thereby improving the overall sealing performance and reducing the risk of leakage.

[0012] (2) The present invention cooperates with the rubber strip, the rubber sealing bag and the memory alloy pre-tightening T-shaped block so that the rubber sealing bag drives the rubber strip to contact the memory alloy pre-tightening T-shaped block. When the rubber strip contacts the memory alloy pre-tightening T-shaped block, the friction force is increased, which helps the rubber sealing bag to stably remain on the bottom of the memory alloy pre-tightening T-shaped block, and prevents the memory alloy pre-tightening T-shaped block from being displaced or offset from the rubber sealing bag after deformation. Through the action of friction, the durability and reliability between the rubber sealing bag and the memory alloy pre-tightening T-shaped block are enhanced.

[0013] (3) The present invention cooperates with the air pressure spray bag, the pressure plate, the guide hole and the liquid inlet pipe so that the epoxy resin coating inside the air pressure spray bag flows to the surface of the memory alloy pre-tightening T-shaped block through the guide hole, and can form a strong protective film on the surface of the memory alloy pre-tightening T-shaped block to prevent moisture, oil and other dirt in the external environment from corroding the metal surface; at the same time, through the cooperation of the long groove, the pressure plate and the memory alloy pre-tightening T-shaped block, the long groove can help to evenly distribute the contact pressure between the pressure plate and the memory alloy pre-tightening T-shaped block, thereby preventing the problem of damage or fatigue of the surface of the memory alloy pre-tightening T-shaped block caused by uneven pressure; at the same time, through the cooperation of the guide hole and the arc block, the arc block will block the liquid inlet of the liquid inlet pipe, thereby preventing oil and dirt from entering the interior of the liquid inlet pipe, causing the problem of blockage of the liquid inlet pipe. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 A schematic diagram of the present invention as a whole;

[0015] Figure 2 A schematic diagram of a side section of the present invention;

[0016] Figure 3 This is a structural diagram of a needle valve guide column of the present invention;

[0017] Figure 4 For the present invention Figure 3 Schematic diagram of the structure at A in the middle;

[0018] Figure 5 This is a structural diagram of the anti-gap device of the present invention;

[0019] Figure 6 This is a schematic diagram of the structure of the air pressure spray bag of the present invention;

[0020] Figure 7 This is a structural diagram of the pressure plate of the present invention;

[0021] Figure 8 It is a structural schematic diagram of the arc block of the present invention.

[0022] In the figure: 1. Needle valve body; 2. Needle valve guide column 1; 3. Pressure-bearing cone block; 4. Needle valve guide column 2; 5. Sealing cone block; 6. Memory alloy pre-tightening T-shaped block; 7. Anti-gap device; 71. Moving ring; 72. Rubber sealing bag; 73. Spring 1; 74. Rubber strip; 8. Anti-corrosion device; 81. Housing; 82. Air pressure spray bag; 83. Pressure plate; 84. Guide hole; 85. Liquid inlet pipe; 86. Long groove; 87. Arc block; 88. Spring 2. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0024] See also Figures 1-8 One embodiment of the present invention is: a preload adaptive mechanism for the conical seal of a diesel engine injector, comprising a needle valve body 1, which is made of a high temperature and high pressure resistant alloy material such as Inconel as the frame of the entire structure. 718 or GH4169 manufacturing, the inner wall of the needle valve body 1 is fixedly connected with a needle valve guide column 2, the bottom of the needle valve guide column 2 is fixedly connected with a pressure-bearing cone block 3, the bottom of the pressure-bearing cone block 3 is fixedly connected with a needle valve guide column 2 4, the bottom of the needle valve guide column 2 4 is fixedly connected with a sealing cone block 5, the surface of the sealing cone block 5 is coated with a diamond-like film with a thickness of 5-10μm, and the deposition process of the diamond-like film adopts the PECVD method with a gas ratio of CH4:H2=1:3-1:5. The top of the needle valve guide column 2 is fixedly connected with a memory alloy pre-tightening T-shaped block 6, the phase change hysteresis temperature of the memory alloy in the memory alloy pre-tightening T-shaped block 6 is ≤10℃, and the strain rate is 0.3-0.8mm / 10℃. The inner wall of the needle valve body 1 is provided with an anti-clearance device 7, which includes a moving ring 71, the outer wall of the moving ring 71 is slidably connected to the inner wall of the needle valve body 1, and the top of the moving ring 71 is fixed. A rubber sealing bag 72 is fixedly connected, and a spring 73 is arranged between the movable ring 71 and the needle valve body 1. Through the arrangement of the above structure, the upward movement of the movable ring 71 will squeeze the rubber sealing bag 72, so the rubber sealing bag 72 will be deformed due to the interaction between the movable ring 71 and the memory alloy pre-tightening T-block 6. Since the memory alloy pre-tightening T-block 6 can change according to the working conditions, especially when the pressure and temperature fluctuate, the change of the memory alloy pre-tightening T-block 6 will cause the gap between the memory alloy pre-tightening T-block 6 and the needle valve body 1 and the needle valve guide column 2 to change, making it difficult for the memory alloy pre-tightening T-block 6 to seal these gaps. Therefore, the deformation of the rubber sealing bag 72 will seal the gap between the memory alloy pre-tightening T-block 6 and the needle valve body 1 and the needle valve guide column 2, preventing the problem of poor sealing in local areas, thereby improving the overall sealing performance and reducing the risk of leakage.

[0025] The anti-gap device 7 also includes two rubber strips 74, the bottoms of the two rubber strips 74 are fixedly connected to the top of the rubber sealing bag 72, the rubber sealing bag 72 is located on the displacement trajectory of the memory alloy pre-tightening T-shaped block 6, and the two rubber strips 74 are located on the displacement trajectory of the memory alloy pre-tightening T-shaped block 6. Through the setting of the above structure, the rubber sealing bag 72 will drive the rubber strips 74 to contact the memory alloy pre-tightening T-shaped block 6. When the rubber strips 74 contact the memory alloy pre-tightening T-shaped block 6, the friction force can be increased to help the rubber sealing bag 72 remain stably on the bottom of the memory alloy pre-tightening T-shaped block 6, and prevent the memory alloy pre-tightening T-shaped block 6 from being displaced or offset from the rubber sealing bag 72 after deformation. Through the action of friction, the durability and reliability between the rubber sealing bag 72 and the memory alloy pre-tightening T-shaped block 6 are enhanced.

[0026] When in use, during the operation of the engine, the memory alloy of the memory alloy pre-tightening T-shaped block 6 can sense temperature changes and adjust its shape, thereby realizing dynamic adjustment of the sealing pre-tightening force. When the memory alloy of the memory alloy pre-tightening T-shaped block 6 is changing, the memory alloy pre-tightening T-shaped block 6 will contact the rubber sealing bag 72, thereby causing the rubber sealing bag 72 to move downward. The downward movement of the rubber sealing bag 72 drives the moving ring 71 to move downward. The downward movement of the moving ring 71 will squeeze the spring 1 73. When the change of the memory alloy pre-tightening T-shaped block 6 is completed, the spring 1 73 will reset by its own elastic force. The reset of the spring 1 73 will push the moving ring 71 to move upward. The upward movement of the moving ring 71 will squeeze the rubber sealing bag 72. Therefore, the rubber sealing bag 72 will be deformed by the interaction between the moving ring 71 and the memory alloy pre-tightening T-shaped block 6. Since the memory alloy pre-tightening T-shaped block 6 can change according to working conditions, especially when pressure and temperature fluctuate. The change of the memory alloy pre-tightening T-shaped block 6 will cause the gap between the memory alloy pre-tightening T-shaped block 6 and the needle valve body 1 and the needle valve guide column 2 to change, making it difficult for the memory alloy pre-tightening T-shaped block 6 to seal these gaps. Therefore, the deformation of the rubber sealing bag 72 will seal the gap between the memory alloy pre-tightening T-shaped block 6 and the needle valve body 1 and the needle valve guide column 2, preventing the problem of poor sealing in local areas, thereby improving the overall sealing performance and reducing the risk of leakage; at the same time, the rubber sealing bag 72 will drive the rubber strip 74 to contact the memory alloy pre-tightening T-shaped block 6. When the rubber strip 74 contacts the memory alloy pre-tightening T-shaped block 6, it can increase the friction and help the rubber sealing bag 72 to remain stably on the bottom of the memory alloy pre-tightening T-shaped block 6, preventing the memory alloy pre-tightening T-shaped block 6 from being displaced or offset from the rubber sealing bag 72 after deformation. Through the action of friction, the durability and reliability between the rubber sealing bag 72 and the memory alloy pre-tightening T-shaped block 6 are enhanced.

[0027] See also Figure 1 - Figure 8On the basis of the above embodiment, in another embodiment of the present invention, an anti-corrosion device 8 is provided on the top of the needle valve body 1, and the anti-corrosion device 8 includes a shell 81, and an air pressure spray bag 82 is fixedly connected to the top of the inner wall of the shell 81, and a pressure plate 83 is fixedly connected to the bottom of the air pressure spray bag 82. A plurality of guide holes 84 are opened at the bottom of the pressure plate 83, and a liquid inlet pipe 85 is fixedly passed through the outer wall of the shell 81. The end of the liquid inlet pipe 85 away from the shell 81 is fixedly connected to the outer wall of the air pressure spray bag 82, and the bottom of the pressure plate 83 is in contact with the top of the memory alloy pre-tightening T-shaped block 6. Through the arrangement of the above structure, the epoxy resin coating inside the air pressure spray bag 82 will flow to the surface of the memory alloy pre-tightening T-shaped block 6 through the guide holes 84, and can form a solid protective film on the surface of the memory alloy pre-tightening T-shaped block 6 to prevent moisture, oil and other dirt in the external environment from corroding the metal surface.

[0028] Several long grooves 86 are provided at the bottom of the pressure plate 83. Through the above-mentioned structural arrangement, the long grooves 86 can help to evenly distribute the contact pressure between the pressure plate 83 and the memory alloy pre-tightening T-shaped block 6, thereby preventing the surface of the memory alloy pre-tightening T-shaped block 6 from being damaged or fatigued due to uneven pressure.

[0029] The outer wall of the shell 81 is slidably connected to an arc block 87, and a spring 2 88 is arranged between the arc block 87 and the needle valve body 1. The outer arc surface of the arc block 87 is fixed with a long block for pushing the arc block 87 to move. Through the setting of the above structure, the arc block 87 will block the liquid inlet of the liquid inlet pipe 85, thereby preventing oil and dirt from entering the interior of the liquid inlet pipe 85 and causing the problem of blockage of the liquid inlet pipe 85.

[0030] When in use, the epoxy resin coating is injected into the air pressure spraying bag 82 through the liquid inlet pipe 85. When the memory alloy pre-tightening T-shaped block 6 is deformed, the upper part of the memory alloy pre-tightening T-shaped block 6 pushes the pressure plate 83 to squeeze the air pressure spraying bag 82. After the air pressure spraying bag 82 is squeezed, the epoxy resin coating inside the air pressure spraying bag 82 flows through the guide hole 84 to the surface of the memory alloy pre-tightening T-shaped block 6, which can form a solid protective film on the surface of the memory alloy pre-tightening T-shaped block 6 to prevent moisture, oil and other dirt in the external environment from corroding the metal surface. When the disc 83 contacts the memory alloy pre-tightening T-shaped block 6, the long groove 86 at the bottom of the pressure plate 83 contacts the memory alloy pre-tightening T-shaped block 6. The long groove 86 can help to evenly distribute the contact pressure between the pressure plate 83 and the memory alloy pre-tightening T-shaped block 6, thereby preventing the surface of the memory alloy pre-tightening T-shaped block 6 from being damaged or fatigued due to uneven pressure; when the epoxy resin coating does not need to be injected, the arc block 87 will block the liquid inlet of the liquid inlet pipe 85, thereby preventing oil and dirt from entering the interior of the liquid inlet pipe 85, causing the liquid inlet pipe 85 to be blocked.

[0031] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A preload force adaptive mechanism for a conical seal of a diesel engine injector, comprising a needle valve body (1), characterized in that: The inner wall of the needle valve body (1) is fixedly connected to a needle valve guide column 1 (2), the bottom of the needle valve guide column 1 (2) is fixedly connected to a pressure-bearing cone block (3), the bottom of the pressure-bearing cone block (3) is fixedly connected to a needle valve guide column 2 (4), the bottom of the needle valve guide column 2 (4) is fixedly connected to a sealing cone block (5), the top of the needle valve guide column 1 (2) is fixedly connected to a memory alloy pre-tightening T-shaped block (6), the inner wall of the needle valve body (1) is provided with an anti-gap device (7), the anti-gap device (7) includes a moving ring (71), the outer wall of the moving ring (71) is slidably connected to the inner wall of the needle valve body (1), the top of the moving ring (71) is fixedly connected to a rubber sealing bag (72), and a spring 1 (73) is provided between the moving ring (71) and the needle valve body (1).

2. The preload force adaptive mechanism for the conical seal of a diesel engine injector according to claim 1, characterized in that: The anti-gap device (7) further comprises two rubber strips (74), the bottoms of the two rubber strips (74) being fixedly connected to the top of the rubber sealing bag (72).

3. The preload force adaptive mechanism for the conical seal of a diesel engine injector according to claim 2, characterized in that: The rubber sealing bag (72) is located on the displacement track of the memory alloy pre-tightening T-shaped block (6), and the two rubber strips (74) are located on the displacement track of the memory alloy pre-tightening T-shaped block (6).

4. The preload force adaptive mechanism for the conical seal of a diesel engine injector according to claim 1, characterized in that: The top of the needle valve body (1) is provided with an anti-corrosion device (8), and the anti-corrosion device (8) includes a shell (81), the top of the inner wall of the shell (81) is fixedly connected to a pneumatic spray bag (82), the bottom of the pneumatic spray bag (82) is fixedly connected to a pressure plate (83), and the bottom of the pressure plate (83) is provided with a plurality of guide holes (84), and the outer wall of the shell (81) is fixedly penetrated by a liquid inlet pipe (85), and the end of the liquid inlet pipe (85) away from the shell (81) is fixedly connected to the outer wall of the pneumatic spray bag (82).

5. The preload force adaptive mechanism for the conical seal of a diesel engine injector according to claim 4, characterized in that: The bottom of the pressure plate (83) is provided with a plurality of long grooves (86).

6. The preload force adaptive mechanism for the conical seal of a diesel engine injector according to claim 4, characterized in that: The outer wall of the housing (81) is slidably connected to an arc block (87), and a second spring (88) is provided between the arc block (87) and the needle valve body (1).

7. The self-adaptive preload mechanism for the conical seal of a diesel engine injector according to claim 4, characterized in that: The bottom of the pressure plate (83) contacts the top of the memory alloy pre-tightening T-shaped block (6).

8. The preload force adaptive mechanism for the conical seal of a diesel engine injector according to claim 6, characterized in that: A long block for pushing the arc block (87) to move is fixed on the outer arc surface of the arc block (87).

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