Rocker arm bearing

Abstract

A rocker arm bearing comprises an outer ring and a mandrel, the outer ring and the mandrel are in direct contact to form a rotating relation, a lubricating groove is formed in the end face of the side, corresponding to the mandrel, of the outer ring, and the inner diameter of the lubricating groove is larger than that of the outer ring. The lubricating groove comprises a plurality of oil storage grooves filled with lubricating grease, the oil storage grooves are connected with one another, and an oil film is formed between the lubricating groove and the mandrel through the lubricating grease in the oil storage grooves. The bearing has the advantages that the lubricating groove is formed in the end face of the outer ring, lubricating grease is filled in the lubricating groove to form the oil storage groove, and continuous and effective lubrication is achieved. The inner diameter of the lubricating groove is larger than that of the outer ring, the storage amount of lubricating grease is increased, and the lubricating requirement of the bearing in long-term operation is met. And the formation of the oil film is beneficial to reducing direct contact, reducing friction and heat generation, prolonging the service life of the bearing, and improving the rotating efficiency and reliability at the same time.

Description

Technical Field

[0001] The utility model relates to a bearing, in particular to a rocker arm bearing. Background Art

[0002] Rocker bearings are key components in large automotive and marine engines, primarily guiding and supporting reciprocating components such as pistons and connecting rods. Designed to withstand the stresses of high loads and high-speed operation, these bearings require excellent wear resistance and stability. Rocker bearings typically consist of a core shaft, outer ring, and needle rollers, all made from bearing steel or similar steels.

[0003] Chinese patent document CN213039661U discloses a rocker arm bearing comprising a roller and a retaining frame, wherein the retaining frame comprises two annular frames, a plurality of locking strips being arranged between the two annular frames, the plurality of locking strips being evenly distributed along the circumference of the annular frames, the locking strips being used to separate the rollers, and a window hole being formed between two adjacent locking strips and the two annular frames, the window hole being capable of accommodating the plurality of rollers.

[0004] The above solution can accommodate medium-to-high speed or high-speed operation. However, it has the following drawbacks: When load capacity needs to be increased, this can only be achieved by increasing the diameter and length of the needle rollers. This results in an increase in the size of the retainer, as well as the outer diameter and axial dimensions of the entire rocker bearing. Therefore, it cannot meet the current trend towards miniaturization of overall structures. Furthermore, the increased size of the needle rollers leads to speed differences between the radial and axial ends, which in turn increases friction during rocker bearing operation. Utility Model Content

[0005] In view of the deficiencies in the prior art, the utility model provides a rocker arm bearing which reduces friction during operation.

[0006] To achieve the above-mentioned purpose, the technical solution of the present invention is as follows: a rocker arm bearing, comprising an outer ring and a core shaft, the outer ring and the core shaft are in direct contact to form a rotational relationship, a lubrication groove is provided on the end face of the outer ring corresponding to the side of the core shaft, the lubrication groove forms a space between the outer ring and the core shaft, the lubrication groove comprises a plurality of oil storage tanks filled with grease and the oil storage tanks are interconnected, the lubrication groove forms an oil film between the grease in the oil storage tank and the core shaft.

[0007] The beneficial effects of the present invention are as follows: the design of this rocker bearing achieves continuous and effective lubrication by providing a lubrication groove on the end face of the outer ring and filling the groove with grease to form an oil reservoir. The inner diameter of the lubrication groove is larger than the inner diameter of the outer ring, which increases the storage capacity of grease and ensures the lubrication requirements of the bearing during long-term operation. The interconnected design between the oil reservoirs allows the grease to be evenly distributed, reducing wear caused by uneven lubrication. In addition, the formation of an oil film helps to reduce direct contact, reduce friction and heat generation, extend the service life of the bearing, and improve rotational efficiency and reliability. In addition, since the needle rollers are eliminated, the direct contact between the outer ring and the core shaft can effectively reduce the impact of the needle rollers on the entire rocker bearing.

[0008] Furthermore, an oil filling hole is provided on the outer ring, and a connecting channel is formed between the oil filling hole and the oil storage tank, and the aperture of the connecting channel is smaller than the apertures of the oil storage tank and the oil filling hole.

[0009] The addition of an oil filling hole and a connecting channel allows for more convenient grease replenishment and maintenance. The connecting channel between the oil filling hole and the oil reservoir allows grease to be added directly to the reservoir. The smaller diameter of the connecting channel than the reservoir and oil filling hole helps control the flow of grease, preventing the rapid injection of excessive grease and thus avoiding grease spillage or waste. This structure also helps maintain internal bearing cleanliness, reduces the ingress of impurities, and further improves bearing stability and durability. This improvement makes bearing maintenance more efficient, extends bearing maintenance cycles, reduces maintenance costs, and improves equipment operating efficiency.

[0010] Furthermore, the outer ring is also provided with an oil pressure piece that cooperates with the oil filling hole. A sealing fit is formed between the oil pressure piece and the oil filling hole. During the process of cooperation between the oil pressure piece and the oil filling hole, the grease in the oil filling hole is squeezed into the oil storage tank.

[0011] The seal between the oil pressure piece and the oil filling hole improves grease injection efficiency and sealing. The oil pressure piece squeezes the grease from the oil filling hole into the oil reservoir during the filling process, ensuring even distribution and effectively filling the reservoir. This design not only improves grease injection efficiency but also reduces grease leakage and waste caused by improper operation. Furthermore, the seal helps prevent the intrusion of external contaminants, keeps the bearing interior clean, reduces wear, and extends bearing life. Overall, this improvement improves bearing maintenance convenience, enhances bearing sealing and durability, and thus improves the reliability and economic benefits of the entire equipment.

[0012] Furthermore, the oil filling hole includes an extrusion hole arranged near one side of the core shaft, the extrusion hole is connected to the connecting channel and its cross section is gradually reduced in diameter toward the core shaft, and the front end of the oil pressure piece is arranged corresponding to the shape of the extrusion hole.

[0013] By providing an extrusion hole in the oil filling hole, with its aperture tapering toward the core shaft, combined with the corresponding external design of the front end of the oil pressure piece, more precise and efficient grease injection is achieved. The tapered extrusion hole design helps to push the grease evenly and continuously into the oil reservoir during extrusion of the oil pressure piece, ensuring a more uniform distribution of grease inside the bearing and reducing local over-lubrication or under-lubrication. At the same time, this structure also helps to reduce the resistance of the grease during the injection process, making it easier for the grease to flow to the areas that need lubrication. The matching design of the front end of the oil pressure piece and the external shape of the extrusion hole ensures sealing and ease of operation during the oil filling process, avoiding grease leakage and waste. This improvement not only improves the lubrication effect of the bearing, but also enhances the durability of the bearing and the ease of maintenance, helping to reduce maintenance costs and improve the operating efficiency of the equipment.

[0014] Furthermore, the outer ring is sintered from silicon nitride material, with a sintered porosity of ≤0.2%, a maximum pore diameter of ≤20 μm, and a surface hardness of HV1 1650-1800.

[0015] The outer ring, sintered from silicon nitride, has extremely low porosity and finely controlled pore size, which significantly improves the strength and wear resistance of the bearing. Silicon nitride is known for its excellent thermal stability, high hardness, and good chemical inertness, properties that enable bearings to perform well in high-temperature, high-pressure, and corrosive environments. The sintered porosity is controlled below 0.2%, ensuring the density and uniformity of the material, reducing internal weaknesses, and thus improving the reliability and durability of the bearing. The maximum pore size is controlled within 20 microns, further enhancing the overall performance of the material and reducing stress concentration caused by porosity. The surface hardness reaches HV1 1650-1800, which means that the bearing surface has extremely high wear resistance and impact resistance, which can effectively resist wear and extend service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is an axonometric diagram of an embodiment of the present utility model;

[0017] Figure 2 A cross-sectional view of an embodiment of the present utility model;

[0018] Figure 3 This is a partial enlarged view of the lubrication groove of the embodiment of the utility model. DETAILED DESCRIPTION

[0019] The utility model embodiment of a rocker arm bearing is as follows Figure 1-3 As shown, the bearing comprises an outer ring 1 and a core shaft 2 in direct contact for rotational engagement. A lubrication groove 11 is provided on the end face of the outer ring 1 on the side corresponding to the core shaft 2. This lubrication groove 11 creates a certain space between the outer ring 1 and the core shaft 2. Within the lubrication groove 11 are several interconnected, semicircular oil reservoirs 111, forming a wavy pattern when connected. Grease is stored in the oil reservoirs 111 to form an oil film between the outer ring 1 and the core shaft 2 during bearing operation, effectively reducing friction between them.

[0020] To facilitate the refilling of consumed grease, the outer ring 1 is provided with an oil filling hole 12 and an oil pressure piece 13 that forms a seal with it. This seal can be achieved by forming a threaded fit between the oil filling hole 12 and the oil pressure piece 13, or by providing a slot in the middle of the oil pressure piece 13 for the sealing ring to achieve a better sealing effect, or by combining the two. An extrusion hole 121 is provided near the core shaft 2, with its cross-section tapering toward the core shaft 2. The front end of the oil pressure piece 13 is provided with an extrusion portion 131 that matches the shape of the extrusion hole 121. At the front end of the extrusion hole 121 is a connecting channel 122 that connects to the oil reservoir 111.

[0021] In addition, without affecting the overall strength of the bearing, the above-mentioned lubrication grooves 11, oil filling holes 12 and oil pressure pieces 13 can be provided in multiple groups to further reduce the friction between the outer ring 1 and the core shaft 2; or multiple lubrication grooves 11 can be provided and the oil filling action of multiple lubrication grooves 11 can be achieved through a group of oil filling holes 12 and oil pressure pieces 13.

[0022] The above embodiment is only one preferred embodiment of the present invention. Common changes and substitutions made by those skilled in the art within the scope of the technical solution of the present invention are all included in the protection scope of the present invention.

Claims

1. A rocker arm bearing, comprising an outer ring and a core shaft, characterized in that: The outer ring and the core shaft are in direct contact to form a rotational relationship. A lubrication groove is provided on the end face of the outer ring corresponding to the core shaft. The lubrication groove forms a space between the outer ring and the core shaft. The lubrication groove includes several oil storage tanks filled with grease and the oil storage tanks are interconnected. The lubrication groove forms an oil film between the grease in the oil storage tank and the core shaft.

2. The rocker arm bearing according to claim 1, characterized in that: The outer ring is also provided with an oil filling hole, and a connecting channel is formed between the oil filling hole and the oil storage tank. The aperture of the connecting channel is smaller than the apertures of the oil storage tank and the oil filling hole.

3. The rocker arm bearing according to claim 2, characterized in that: The outer ring is also provided with an oil pressure piece that cooperates with the oil filling hole. A sealing fit is formed between the oil pressure piece and the oil filling hole. During the process of cooperation between the oil pressure piece and the oil filling hole, the grease in the oil filling hole is squeezed into the oil storage tank.

4. The rocker arm bearing according to claim 3, characterized in that: The oil filling hole includes an extrusion hole arranged near one side of the core shaft. The extrusion hole is connected to the connecting channel and its cross section is gradually reduced in diameter toward the core shaft. The front end of the oil pressing member is arranged corresponding to the shape of the extrusion hole.

5. The rocker arm bearing according to claim 1, characterized in that: The outer ring is sintered from silicon nitride material, with a sintered porosity of ≤0.2%, a maximum pore diameter of ≤20 μm, and a surface hardness of HV1 1650-1800.

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