Deep groove ball bearings for electric compressors in new energy vehicles

Abstract

A deep groove ball bearing for an electric compressor of a new energy vehicle includes an outer ring, an inner ring, and a plurality of balls. The balls are placed in a raceway between the outer ring and the inner ring and are fixed by a retaining frame. The retaining frame is composed of a first frame and a second frame, both of which are provided with a ball pocket and a riveted portion. The first frame and the second frame are fixed by rivets on the riveted portion. The ball pocket cooperates to place and limit the balls. The riveted portion of the first frame is provided with a positioning block, and the corresponding position of the second frame is provided with a positioning groove. During riveting, the positioning block deforms and snaps into the positioning groove. The present invention achieves dual fixation during the riveting process through the cooperation of the positioning block and the positioning groove, thereby improving the reliability of the bearing under high speed and high load conditions. At the same time, it simplifies the assembly process, reduces the risk of loosening, and extends the service life. It has significant practicality and economic benefits.

Description

Technical Field

[0001] The present invention relates to a deep groove ball bearing, and in particular to a deep groove ball bearing for an electric compressor of a new energy vehicle. Background Art

[0002] In new energy vehicles, electric compressors are key components, and their core supporting components, deep groove ball bearings, are widely used in high-speed operating environments. Deep groove ball bearings are primarily responsible for supporting the rotor of the electric compressor and ensuring smooth operation under high speed and high load conditions. Their operating scenarios typically include high temperatures, high speeds, and complex dynamic load environments. During use, the bearings need to withstand axial and radial forces from within the electric compressor while ensuring low noise, high reliability, and long life. To meet these requirements, deep groove ball bearings typically use a rivet-connected cage structure to separate the rolling elements and guide their motion trajectory to reduce friction and wear.

[0003] However, existing deep groove ball bearings have significant drawbacks. Particularly under harsh operating conditions such as rapid speed changes, lean lubrication, or impact loads, the retainer-rivet connection is susceptible to fracture due to stress concentration. This failure mode not only causes unstable bearing operation but can also trigger failure of the entire electric compressor, impacting the performance and reliability of new energy vehicles. Furthermore, the resulting fragments can further damage the bearing's internal structure, leading to more severe secondary damage and limiting its application in high-performance scenarios. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the present invention provides a deep groove ball bearing for an electric compressor of a new energy vehicle, which has a more stable structure after the retainer is riveted.

[0005] To achieve the above-mentioned objectives, the technical solution of the present invention is as follows: a deep groove ball bearing for an electric compressor of a new energy vehicle, comprising a matching outer ring and an inner ring, a raceway for uniformly placing a plurality of balls being formed between the outer ring and the inner ring, and the plurality of balls being all sleeved in the same retaining frame, the retaining frame comprising a first frame body and a second frame body that match each other, the first frame body and the second frame body both comprising a ball pocket portion for placing the balls and a riveted portion for riveting, the first frame body and the second frame body are fixed by riveting rivets on the riveted portion, and after the first frame and the second frame are fixed, the two ball pocket portions cooperate to place and limit the rolling elements, a positioning block protruding from the end face is provided on the riveted portion of the first frame body corresponding to the end face of the second frame body, a positioning groove for placing the positioning block is provided on the riveted portion of the second frame body corresponding to the end face of the first frame body, and the positioning block is deformed in the positioning groove after riveting and is stuck in the positioning groove.

[0006] The beneficial effects of the present invention are as follows: by providing a positioning block on the riveting portion of the first frame and providing a positioning groove at the corresponding position of the second frame, the positioning block is deformed and clamped in the positioning groove during the riveting process. This design not only enhances the overall connection strength of the retaining frame, but also avoids the singleness of relying solely on rivet fixation. As a preferred method, the connection effect can be optimized by controlling the height and deformation of the positioning block. For example, the height of the positioning block can be slightly greater than the depth of the positioning groove to ensure that sufficient compressive stress is generated during riveting to complete the deformation embedding. In addition, due to the clamping effect between the positioning block and the positioning groove, even if the rivet is loose or fails, the retaining frame can still maintain a certain structural stability, thereby extending the service life of the bearing.

[0007] Furthermore, an arc surface is provided between the side end surface and the top end surface of the positioning block, and guide grooves are provided around the bottom of the positioning groove corresponding to the arc surface of the positioning block.

[0008] The design of providing an arc surface between the side end face and the top end face of the positioning block, and providing a guide groove at the bottom of the positioning groove, can effectively improve the assembly efficiency and uniformity during the deformation process. The arc surface reduces the friction resistance when the positioning block enters the positioning groove. At the same time, the guide groove can guide the positioning block to quickly align and enter the positioning groove, reducing the difficulty of assembly. As a preferred method, the width of the guide groove can be slightly larger than the maximum lateral dimension of the positioning block to facilitate initial positioning. This design can also promote uniform deformation of the positioning block along the guide groove direction during the riveting process, avoid material cracking due to local stress concentration, and further improve the reliability of the retaining frame.

[0009] Furthermore, the positioning groove is rectangular, and embedding grooves are provided at the four corners of the guide groove. The deformation of the positioning block during the riveting process can extend into the embedding groove.

[0010] The positioning groove adopts a rectangular design, and embedded grooves are set at its four corners, so that the positioning block can absorb excess deformation through the embedded grooves during the riveting process, thereby enhancing the firmness of the connection. The rectangular positioning groove has a high shape accuracy, which is convenient for cooperation with the positioning block, while the embedded groove provides additional space for the positioning block to deform and expand, avoiding damage to other components due to excessive deformation pressure. As a preferred method, the depth of the embedded groove can be designed to be about half the depth of the positioning groove to ensure that the positioning block can be embedded after deformation without protruding excessively and affecting the overall structure. In addition, the presence of the embedded groove can also disperse the internal stress generated during the riveting process and reduce the risk of fatigue failure.

[0011] Furthermore, the embedding groove includes an entry section and a locking section, and the entry section and the locking section are arranged to be smaller in the front and larger in the back, and are in a water drop shape when connected.

[0012] The embedding groove is divided into an entry section and a clamping section, and is designed in a teardrop shape, which can significantly improve the fixing effect of the positioning block after deformation. The smaller opening of the entry section facilitates the initial embedding of the positioning block, while the larger space of the clamping section provides a stable accommodation area for the positioning block after deformation to prevent it from rebounding and detaching. This design not only improves the efficiency of deformation fixation, but also enhances the impact resistance of the retaining frame. As a preferred method, the width of the entry section can be designed to be 60%-70% of the width of the clamping section to ensure that the positioning block enters smoothly while having sufficient fixing force. In addition, the teardrop-shaped embedding groove can also reduce the restriction on the flow of positioning block material during riveting and reduce the probability of micro cracks.

[0013] Furthermore, a transition arc is provided between the ball pocket portion and the riveted portion on each side, and the ball pocket portion and the riveted portion are connected by a transition arc, and the radius of the transition arc is 0.6-0.8 mm.

[0014] The transition arc connecting the ball pocket and the riveted portion effectively alleviates stress concentration at their interface, improving the overall strength and durability of the cage. The rational design of the transition arc avoids material fatigue fractures caused by sharp edges and corners, while optimizing the force transmission path. As a preferred approach, a transition arc radius of 0.7mm can be selected as the standard value, meeting stress dispersion requirements while taking into account the feasibility of the manufacturing process. Furthermore, the transition arc improves the cage's dynamic performance under high-speed operating conditions, reducing vibration and noise, thereby enhancing the bearing's operating smoothness and service life.

[0015] Furthermore, the inner ring curvature coefficient is 0.505, the outer ring curvature coefficient is 0.520, the inner and outer ring rib coefficients are 0.2-0.3, and the cage ball pocket radius coefficient is 0.510.

[0016] The above curvature setting minimizes the contact stress between the balls and the inner and outer rings, optimizes the bearing load-bearing performance, and can maintain smooth rotation of the balls between the inner and outer rings without jamming.

[0017] Furthermore, the inner ring, outer ring and balls are all subjected to surface heat treatment, the inner ring and outer ring are subjected to CN co-penetration treatment and the surface has a penetration layer depth of more than 0.30mm, the cage material is a metal cage and the carbon content of the cage material is more than 0.1%.

[0018] The cage and rivets are subjected to special surface heat treatment to improve the assembly stress of the cage after riveting from the perspective of material and heat treatment, thereby improving its own strength and thus improving the riveting quality of the cage. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A partial cross-sectional view of an embodiment of the present invention;

[0020] Figure 2 A partial cross-sectional view of a positioning groove according to an embodiment of the present invention;

[0021] Figure 3 This is a partial enlarged view of the connection between the riveting portion and the ball pocket portion of an embodiment of the present invention;

[0022] Figure 4 This is a diagram of contact stress ratio-inner ring curvature coefficient according to an embodiment of the present invention. DETAILED DESCRIPTION

[0023] The embodiment of the present invention is a deep groove ball bearing for an electric compressor of a new energy vehicle. Figure 1 Figure 4 shows an outer ring 1 and an inner ring 2, with a raceway 3 formed between them for accommodating a number of balls 5. These balls 5 are collectively housed within a cage 4, which consists of a first frame 41 and a second frame 42. The first and second frames 41, 42 are secured together by riveting, specifically by applying rivets to the riveting portion 44.

[0024] To enhance the connection strength of retainer 4, a positioning structure is added in addition to the rivet pressing. The riveting portion 44 of the first frame 41 is equipped with a protruding positioning block 411, while the riveting portion 44 of the second frame 42 is equipped with a corresponding positioning groove 421. The positioning block 411 deforms during the riveting process and snaps into the positioning groove 421, further strengthening the connection between the two. The positioning block 411 is designed with a circular arc surface 412 between its side end face and top face to reduce stress concentration and facilitate positioning. Guide grooves are also provided around the bottom of the positioning groove 421, which match the circular arc surface 412 of the positioning block 411. The positioning groove 421 is generally rectangular, with embedded grooves 422 designed at its four corners to facilitate the positioning block 411 to deform during riveting and extend into the embedded groove 422. The embedded groove 422 includes an entry section 4221 and a locking section 4222, both of which are designed in a teardrop shape with a smaller front and a larger rear. This design allows the positioning block 411 to more easily enter the embedding groove 422 during deformation, and can better fix the first frame 41 and the second frame 42 after deformation is completed.

[0025] Furthermore, both the first and second frames 41, 42 of the retainer 4 include a ball-shaped pocket 43 and a rivet-shaped portion 44, connected by a transition arc 45. The radius of the transition arc 45 is 0.6-0.8 mm, effectively avoiding stress concentration issues caused by a too-small arc. The ball-shaped pocket 43 houses and positions the ball 5, ensuring smooth rolling within the raceway 3, while the rivet-shaped portion 44 secures the first and second frames 41, 42.

[0026] Because the outer ring curvature coefficient and retainer pocket radius coefficient share the same contact stress trend as the inner ring, this embodiment only provides the inner ring contact stress curve. The relationship between the inner ring curvature coefficient and contact stress ratio shows that a curvature coefficient of 0.505 minimizes contact stress and optimizes bearing load-bearing performance. However, a lower curvature coefficient can easily cause the bearing to seize and become inflexible. Therefore, 0.505 is a suitable minimum curvature coefficient. The outer ring curvature coefficient and retainer pocket radius coefficient share the same contact stress trend as the inner ring, but meet the requirements of equal contact stress design. When the inner ring curvature coefficient is 0.505, the outer ring curvature coefficient is 0.520, and the retainer pocket radius coefficient is 0.510, achieving equal contact stress on the inner and outer rings. The outer ring curvature coefficient is larger than the inner ring, providing a certain degree of centering, thereby facilitating flexible bearing rotation.

[0027] In addition, the inner ring 2, the outer ring 1 and the ball 5 are all subjected to surface heat treatment. The inner ring 2 and the outer ring 1 are subjected to CN co-penetration treatment and the surface has a penetration layer depth of more than 0.30 mm. The retainer 4 is made of metal and the carbon content of the retainer 4 material is more than 0.1% to improve the material properties of the above components.

[0028] The operating principle of this embodiment is as follows: When the bearing is operating, the balls 5 between the outer ring 1 and the inner ring 2 roll along the raceway 3, with the movement of the balls 5 limited and guided by the retainer 4. The first and second frames 41, 42 of the retainer 4 are riveted together, and the positioning block 411 cooperates with the positioning groove 421 to form a stable structure. During the riveting process, the positioning block 411 deforms and snaps into the positioning groove 421. In particular, the design of the embedding groove 422 allows the deformed positioning block 411 to be more firmly fixed in the positioning groove 421, thereby enhancing the overall strength of the retainer 4. Furthermore, the design of the transition arc 45 reduces the possibility of stress concentration, thereby improving the durability of the retainer 4.

[0029] 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 deep groove ball bearing for an electric compressor of a new energy vehicle, comprising a mating outer ring and an inner ring, wherein a raceway is formed between the outer ring and the inner ring for uniformly placing a plurality of balls, wherein the plurality of balls are all sleeved in the same retaining frame, wherein the retaining frame comprises a first frame body and a second frame body that cooperate with each other, wherein the first frame body and the second frame body both comprise a ball pocket portion for placing the balls and a riveting portion for riveting, wherein the first frame body and the second frame body are fixed to each other by riveting rivets on the riveting portion, and after the first frame body and the second frame body are fixed, the two ball pocket portions cooperate to place and limit the rolling elements, and the characteristics are as follows: The riveted portion of the first frame is provided with a positioning block protruding from the end surface corresponding to the second frame, and the riveted portion of the second frame is provided with a positioning groove for placing the positioning block on the end surface corresponding to the first frame, and the positioning block is deformed in the positioning groove and clamped in the positioning groove after riveting; an arc surface is provided between the side end surface and the top end surface of the positioning block, and guide grooves are provided on the four sides of the bottom of the positioning groove corresponding to the arc surface of the positioning block; the positioning groove is rectangular, and embedding grooves are provided at the four corners of the guide groove, and the deformation of the positioning block can extend into the embedding groove during the riveting process; the embedding groove includes an entry section and a clamping section, and the entry section and the clamping section are arranged to be small in the front and large in the back, and are in the shape of a water drop when connected.

2. The deep groove ball bearing for the electric compressor of new energy vehicles according to claim 1, characterized in that: A transition arc is provided between the ball pocket portion and the riveted portion on each side, and the ball pocket portion and the riveted portion are connected by a transition arc, and the radius of the transition arc is 0.6-0.8 mm.

3. The deep groove ball bearing for the electric compressor of new energy vehicles according to claim 1, characterized in that: The inner ring curvature coefficient is 0.505, the outer ring curvature coefficient is 0.520, the inner and outer ring rib coefficients are 0.2-0.3, and the cage ball pocket radius coefficient is 0.

510.

4. The deep groove ball bearing for the electric compressor of new energy vehicles according to claim 1, characterized in that: The inner ring, outer ring and balls are all subjected to surface heat treatment. The inner ring and outer ring are subjected to CN co-penetration treatment and the surface has a penetration layer depth of more than 0.30mm. The cage material is a metal cage and the carbon content of the cage material is more than 0.1%.

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