Self-lubricating bolt
By designing self-lubricating bolts, automatic lubrication is achieved through an oil reservoir, a spiral main oil channel, and an inclined lubrication channel. This solves the problems of high bolt friction and difficulty in lubrication, thereby improving the service life of the bolts and the ease of operation.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- ZHEJIANG TIANGONG FASTENER CO LTD
- Filing Date
- 2025-06-12
- Publication Date
- 2026-04-21
AI Technical Summary
Existing bolts are difficult to tighten and loosen due to high friction, which leads to wear and reduced service life. At the same time, traditional lubrication methods are prone to leakage and are cumbersome to operate, especially in special environments where continuous lubrication is difficult to achieve.
A self-lubricating bolt was designed, comprising an oil reservoir, a spiral main oil passage, and an inclined lubrication oil passage. It utilizes capillary effect and pressure difference to achieve automatic lubrication, and combines nanocrystalline nickel, CrN/DLC composite layer and fluorinated graphene material to improve lubrication effect and wear resistance.
It achieves automatic and continuous lubrication of bolts, reducing maintenance costs and operational difficulty. It is suitable for special environments such as high-altitude operations and confined spaces, improving ease of use and reliability.
Smart Images
Figure CN224149964U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of bolt technology, specifically to a self-lubricating bolt. Background Technology
[0002] In the field of mechanical assembly and engineering, bolts, as a common fastener, are widely used for connecting and fixing various equipment and components. During actual use, when tightening or loosening bolts, significant friction is generated between the bolt and the connected parts. This not only increases the difficulty of operation but also causes wear on the bolt surface, reducing the bolt's service life and connection reliability.
[0003] Currently, the common method to reduce friction between bolts and connected parts is to apply grease or lubricating oil to the bolt surface. However, this traditional lubrication method has many shortcomings. First, the applied grease or lubricating oil is prone to runoff, failing to provide continuous lubrication to the bolt, and the lubrication effect is difficult to guarantee under prolonged use or harsh working conditions. Second, the manual application of lubricant periodically is cumbersome, increasing maintenance costs and manpower. Furthermore, in some special environments, such as working at heights or in confined spaces, lubricating bolts is extremely inconvenient. Therefore, developing a bolt capable of automatic and continuous lubrication is of great significance for improving bolt performance and reducing maintenance costs. Utility Model Content
[0004] To address the shortcomings of the prior art, this utility model provides a self-lubricating bolt.
[0005] The technical solution adopted by this utility model is: a self-lubricating bolt, including an integrally formed hexagonal screw head and a screw rod, the screw rod being provided with external threads, and also including a lubrication system capable of lubricating the sidewall of the screw rod by oil seepage, the lubrication system including an oil storage cavity, an oil cavity cover, a main oil passage and a lubricating oil passage;
[0006] The oil storage chamber is located on a hexagonal screw head, and the oil chamber cover is used to seal the opening of the oil storage chamber;
[0007] The main oil passage has a spiral structure and is located inside the screw along the length of the screw. One end of the main oil passage has an inlet end that communicates with the oil storage chamber.
[0008] The lubricating oil passages are spaced apart on the outer wall of the screw and connected to the main oil passage. The diameter of the lubricating oil passages gradually decreases from one end of the main oil passage to the other end of the outer wall, and the lubricating oil passages are inclined towards the end away from the hexagonal screw head.
[0009] Furthermore, the inner ring of the opening of the oil storage cavity is provided with a concave surface for installing the sealing ring, and the middle part of the oil cavity cover has a convex part for pressing the sealing ring against the concave surface.
[0010] Furthermore, the surface of the sealing ring is provided with at least two raised rings, and the surface of the concave surface is provided with an annular groove that matches the raised rings.
[0011] Furthermore, the opening of the oil storage chamber and the oil chamber cover are both provided with fixed screw holes at intervals, and the oil chamber cover is fixed to the hexagonal screw head by fixing screws.
[0012] Furthermore, the inner wall of the lubricating oil passage is provided with a base layer, a transition layer and a surface layer from the inside out;
[0013] The substrate layer is nanocrystalline nickel with a thickness of 5-8 μm;
[0014] The transition layer is a CrN / DLC composite layer with a thickness of 2-3 μm;
[0015] The surface layer is fluorinated graphene with a thickness of 50-80 nm.
[0016] Furthermore, the angle α of the lubricating oil passage inclined away from the hexagonal screw head is 25-35°.
[0017] The beneficial effects of this utility model are:
[0018] First, by placing the oil storage chamber in the hexagonal screw head, lubricating oil can be effectively stored, avoiding the problem of lubricant loss in traditional application lubrication methods, and enabling continuous lubrication of the screw outer wall through the lubrication system.
[0019] Second, the main oil passage of the spiral structure is set along the length of the screw, which makes the flow of lubricating oil in the screw smoother and more uniform, and allows the lubricating oil to better cover the surface of the screw.
[0020] Third, the lubricating oil passages are spaced on the outer wall of the screw and connected to the main oil passage. Their diameter gradually decreases from one end of the main oil passage to the other end of the outer wall, and they are inclined towards the end away from the hexagonal screw head. This design forms directional lubrication of the lubricating oil, reduces the possibility of blockage, and allows the lubricating oil to penetrate to the contact area between the screw and the connected parts. This reduces lubricating oil waste and enhances the lubrication effect.
[0021] Fourth, this self-lubricating bolt eliminates the need for regular manual application of lubricant, significantly reducing maintenance costs and manpower. It is particularly suitable for special environments where traditional lubrication methods are difficult to operate, such as high-altitude operations and confined spaces, thus significantly improving the convenience and practicality of bolt use.
[0022] In addition to the objectives, features and advantages described above, this utility model has other objectives, features and advantages.
[0023] The present invention will now be described in further detail with reference to the accompanying drawings. Attached Figure Description
[0024] Figure 1 This is a schematic diagram of the structure of this utility model.
[0025] Figure 2 This is a schematic diagram of the oil cavity seal.
[0026] Figure 3 This is a schematic diagram of the sealing ring.
[0027] Figure 4 This is a cross-sectional schematic diagram of the present invention.
[0028] Figure 1-4 In the middle: 1. Hexagonal screw head; 2. Screw; 3. External thread; 4. Oil reservoir; 5. Oil reservoir cover; 6. Main oil passage; 7. Lubricating oil passage; 8. Inlet end; 9. Sealing ring; 10. Concave surface; 11. Protrusion; 12. Protruding ring; 13. Ring groove; 14. Fixing screw hole; 15. Angle α. Detailed Implementation
[0029] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0030] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.
[0031] This utility model provides a self-lubricating bolt.
[0032] In this embodiment, refer to Figure 1-4 The self-lubricating bolt includes an integrally formed hexagonal screw head 1 and a screw rod 2. The screw rod 2 is provided with an external thread 3. It also includes a lubrication system that can lubricate the side wall of the screw rod by oil seepage. The lubrication system includes an oil storage chamber 4, an oil chamber cover 5, a main oil passage 6, and a lubricating oil passage 7.
[0033] The oil storage chamber 4 is located on the hexagonal screw head, and the oil chamber cover 5 covers the opening of the oil storage chamber;
[0034] The main oil passage 6 has a spiral structure and is located inside the screw along the length of the screw. One end of the main oil passage has an inlet end 8 that communicates with the oil storage chamber.
[0035] The lubricating oil passages 7 are spaced apart on the outer wall of the screw and are connected to the main oil passage. The diameter of the lubricating oil passage gradually decreases from one end of the main oil passage to the other end of the outer wall, and the lubricating oil passage is inclined towards the end away from the hexagonal screw head.
[0036] In the above technical solution, an oil reservoir is set in the hexagonal screw head to store lubricating oil, and the spiral main oil channel delivers the lubricating oil to the far end of the screw. The conical and inclined lubricating oil channel utilizes capillary effect and pressure difference to achieve directional penetration of lubricating oil. This achieves automatic lubrication throughout the bolt's entire life cycle, reducing manual maintenance costs; the spiral main oil channel ensures that the lubricating oil is evenly distributed throughout the screw; and the conical lubricating oil channel prevents foreign objects from entering and clogging the system, extending the life of the lubrication system.
[0037] Specifically, the inner ring of the opening of the oil storage cavity is provided with a concave surface 10 for installing the sealing ring 9, and the middle part of the oil cavity cover has a protrusion 11 for pressing the sealing ring 9 to the concave surface.
[0038] In this embodiment, the concave surface of the oil reservoir opening and the convex part of the oil reservoir cover form a compression structure, causing the sealing ring to elastically deform and fill the gap. This enhances the sealing performance of the oil reservoir, prevents lubricating oil leakage, and avoids external moisture and dust from intruding and contaminating the lubricating oil.
[0039] Specifically, the surface of the sealing ring is provided with at least two convex rings 12, and the surface of the concave surface is provided with an annular groove 13 that matches the convex rings.
[0040] In this embodiment, the convex ring and concave groove on the sealing ring surface form a multi-stage labyrinth seal structure, increasing the leakage path length and resistance. This further improves sealing reliability, making it particularly suitable for vibration environments or high-pressure conditions; and extends the lubricating oil replacement cycle.
[0041] Specifically, the opening of the oil storage chamber and the oil chamber cover are both provided with fixing screw holes at intervals, and the oil chamber cover is fixed to the hexagonal screw head by fixing screws.
[0042] In this embodiment, a multi-point fastening structure is formed by the spaced fixing screw holes 14 and screws to balance the force on the cover, while facilitating the disassembly and maintenance of the oil storage chamber.
[0043] Specifically, the inner wall of the lubricating oil passage is provided with a base layer, a transition layer and a surface layer from the inside out;
[0044] The substrate layer is nanocrystalline nickel with a thickness of 5-8 μm;
[0045] The transition layer is a CrN / DLC composite layer with a thickness of 2-3 μm;
[0046] The surface layer is fluorinated graphene with a thickness of 50-80 nm.
[0047] In this embodiment, the nanocrystalline nickel substrate provides a high-hardness matrix, the CrN / DLC composite transition layer enhances the bonding strength, and the fluorinated graphene surface layer reduces the coefficient of friction. This gives the inner wall of the lubricating oil passage excellent wear resistance and corrosion resistance; reduces the flow resistance of the lubricating oil; and improves the penetration efficiency.
[0048] Specifically, the angle a15 at which the lubricating oil passage is inclined toward the end away from the hexagonal screw head is 25-35°.
[0049] In this embodiment, the 25-35° tilt angle allows the lubricating oil to penetrate towards the bolt tightening direction under the combined force of centrifugal force and the direction of thread rotation, thereby improving the lubrication effect.
[0050] Please note to all technical personnel: Although this utility model has been described according to the specific embodiments above, the concept of this utility model is not limited to this utility model. Any modification that utilizes the concept of this utility model will be included within the scope of protection of this patent right.
Claims
1. A self-lubricating bolt, comprising an integrally formed hexagonal screw head and a screw rod, wherein the screw rod is provided with external threads, characterized in that: It also includes a lubrication system capable of lubricating the screw sidewall with oil seepage, the lubrication system including an oil reservoir, an oil reservoir cover, a main oil passage and a lubricating oil passage; The oil storage chamber is located on a hexagonal screw head, and the oil chamber cover is used to seal the opening of the oil storage chamber; The main oil passage has a spiral structure and is located inside the screw along the length of the screw. One end of the main oil passage has an inlet end that communicates with the oil storage chamber. The lubricating oil passages are spaced apart on the outer wall of the screw and connected to the main oil passage. The diameter of the lubricating oil passages gradually decreases from one end of the main oil passage to the other end of the outer wall, and the lubricating oil passages are inclined towards the end away from the hexagonal screw head.
2. The self-lubricating bolt of claim 1, wherein: The inner ring of the opening of the oil storage chamber is provided with a concave surface for installing a sealing ring, and the middle part of the oil chamber cover has a convex part for pressing the sealing ring against the concave surface.
3. The self-lubricating bolt of claim 2, wherein: The surface of the sealing ring is provided with at least two raised rings, and the surface of the concave surface is provided with an annular groove that matches the raised rings.
4. The self-lubricating bolt of claim 1, wherein: The opening of the oil storage chamber and the oil chamber cover are both provided with fixed screw holes at intervals, and the oil chamber cover is fixed to the hexagonal screw head by fixing screws.
5. The self-lubricating bolt of claim 1, wherein: The inner wall of the lubricating oil passage is provided with a base layer, a transition layer and a surface layer from the inside to the outside; The substrate layer is nanocrystalline nickel with a thickness of 5-8 μm; The transition layer is a CrN / DLC composite layer with a thickness of 2-3 μm; The surface layer is fluorinated graphene with a thickness of 50-80 nm.
6. The self-lubricating bolt of claim 1, wherein: The angle α of the lubricating oil passage inclined away from the hexagonal screw head is 25-35°.