Fluid dynamic bearing and motor device

Abstract

A fluid dynamic bearing and a motor device comprising same. The fluid dynamic bearing (100) comprises a central shaft (20) and a bearing (10) sleeved on the periphery of the central shaft; first flow channels (30), a second flow channel (40) and a connecting flow channel (50) are provided between the bearing and the central shaft; the first flow channels and the second flow channel are alternately arranged in the axial direction of the bearing; the connecting flow channel communicates the first flow channels with the second flow channel; the depth of the connecting flow channel is less than the depths of the first flow channels and the depth of the second flow channel; an included angle is formed between the conduction direction of each first flow channel and the conduction direction of the second flow channel; and the adjacent sides of the first and second flow channels have a smaller depth and / or a larger width than the sides farther apart. The flow channel structure decreases the degree of reduction in the volume of a medium on the adjacent sides of the first and second flow channels, reduces the negative pressure generated by the medium on the adjacent sides of the first and second flow channels, is beneficial to ensuring the suspension of the central shaft, and improves the operation stability of the fluid dynamic bearing.

Description

hydrodynamic bearings and motor equipment

[0001] This application claims priority to Chinese Patent Application No. 202411987768.2, filed with the State Intellectual Property Office of China on December 30, 2024, entitled "Hydrodynamic Bearing and Motor Equipment", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of bearing technology, and in particular to a hydrodynamic bearing and motor equipment. Background Technology

[0003] With the development of bearing technology, the performance requirements for equipment are getting higher and higher. Hydrodynamic bearings usually consist of a central shaft, a bearing, and a medium. During the operation of the hydrodynamic bearing, the medium can generate dynamic pressure to suspend the central shaft, so that the central shaft and the bearing do not come into contact, thereby preventing wear and noise and ensuring the stable operation of the hydrodynamic bearing.

[0004] In some applications, bidirectional rotation of the hydrodynamic bearing is required, resulting in hydrodynamic grooves distributed in both clockwise and counterclockwise directions. This causes the stress concentration area in the hydrodynamic grooves to become a low-pressure area during counterclockwise rotation, and vice versa. The reduced medium in the low-pressure area decreases the levitation support force on the central shaft, making it easier for the central shaft and bearing to come into contact, thus reducing the operational stability of the hydrodynamic bearing. Summary of the Invention

[0005] This application provides a hydrodynamic bearing and motor device. By setting the depth and / or width of the side where the first flow channel and the second flow channel are close together in the hydrodynamic bearing, the negative pressure generated on the side where the first flow channel and the second flow channel are close together is reduced and / or there is always sufficient medium to support the central shaft suspension, thus ensuring the stability of the bidirectional rotation of the hydrodynamic bearing.

[0006] In a first aspect, this application provides a hydrodynamic bearing, comprising: a bearing and a central shaft, the bearing being sleeved on the outer periphery of the central shaft, a first flow channel, a second flow channel, and a connecting flow channel being provided between the bearing and the central shaft, the first flow channel and the second flow channel being alternately arranged in the axial direction of the bearing, the connecting flow channel connecting the first flow channel and the second flow channel, the depth of the connecting flow channel being less than the depth of the first flow channel and the depth of the second flow channel, the conduction direction of the first flow channel and the conduction direction of the second flow channel both having an angle with the radial and axial directions of the bearing, the conduction direction of the first flow channel and the conduction direction of the second flow channel having an angle, and the side of the first flow channel and the second flow channel that are close to each other having a smaller depth and / or a larger width than the side that are far away from each other.

[0007] This application provides a hydrodynamic bearing, which includes a central shaft and a bearing sleeved on the outer periphery of the central shaft. The spacer region between the bearing and the central shaft has a first flow channel, a second flow channel, and a connecting flow channel for distributing a medium. The connecting flow channel connects the first and second flow channels, and there is a depth difference between the connecting flow channel and both the first and second flow channels, allowing the hydrodynamic bearing to generate dynamic pressure during operation, thus suspending the central shaft. The conduction directions of the first and second flow channels form an angle, and both also form angles with the radial and axial directions of the bearing, allowing the dynamic pressure generated by the medium in the first and second flow channels to be superimposed, jointly supporting the suspension of the central shaft. By alternating the first and second flow channels in the axial direction of the bearing, bidirectional rotation of the hydrodynamic bearing in both clockwise and counterclockwise directions is achieved.

[0008] The side of the first and second flow channels that are close together has a smaller depth than the side that is far apart, which reduces the negative pressure generated on the side where the first and second flow channels are close together; and / or, the side of the first and second flow channels that are close together has a larger width than the side that is far apart, which allows the medium lost on the side where the first and second flow channels are close together to be replenished in a timely manner. Both of these factors help to reduce the reduction in the medium volume on the side where the first and second flow channels are close together, ensuring that the side where the first and second flow channels are close together has sufficient medium to support the central shaft suspension, thereby ensuring the stability of the hydrodynamic bearing operation.

[0009] In one possible implementation, at least one of the inner wall of the bearing and the outer wall of the central shaft has a groove, which forms the first flow channel and the second flow channel. By providing a groove on at least one of the inner wall of the bearing and the outer wall of the central shaft, the medium is confined by the groove. By forming the first and second flow channels with the groove, the arrangement of the first and second flow channels is simplified, the spacing between the bearing and the central shaft is ensured, and the miniaturization of the hydrodynamic bearing is achieved.

[0010] In one possible implementation, the groove includes at least two first grooves and at least one second groove. The at least two first grooves are located on opposite sides of the second groove in the axial direction of the bearing. The extension directions of both the first and second grooves form angles with the radial and axial directions of the bearing, respectively. An angle is also formed between the extension directions of the first and second grooves. Both the first and second grooves are located on the inner wall of the bearing or the outer wall of the central shaft, forming the first and second flow channels, respectively. By ensuring that the extension directions of the first and second grooves form angles with each other and with both the radial and axial directions of the bearing, the first and second flow channels formed by the first and second grooves satisfy the required angular relationship, ensuring that the first and second flow channels can generate significant dynamic pressure. By positioning at least two first grooves on opposite sides of the second groove in the bearing axial direction, bidirectional rotation of the hydrodynamic bearing is achieved. The at least two first grooves and at least one second groove are located on the inner wall of the bearing or the outer wall of the central shaft, simplifying the arrangement of the first and second grooves and enabling the hydrodynamic pressure at the first and second grooves to have a better superposition effect.

[0011] In one possible implementation, the depth of the end of the first groove that is close to the second groove is 0 to 1 / 3 times the depth of the other end that is far away. By ensuring that the depth of the first groove satisfies the above relationship, the negative pressure generated on the side where the first and second grooves are close together is reduced, which helps to ensure that the side where the first and second grooves are close together has sufficient medium to support the central shaft suspension.

[0012] In one possible implementation, the first and second grooves are alternately arranged in the axial direction of the bearing. The grooves further include a third and a fourth groove, located on the same side of the first and second grooves in the circumferential direction of the bearing. The third and fourth grooves are parallel to the second and first grooves, respectively, with their adjacent ends corresponding to the ends of the second groove furthest from the first groove. By providing the third and fourth grooves, the number of grooves is increased, which is beneficial for increasing the magnitude of the dynamic pressure generated by the hydrodynamic bearing. By ensuring the third and fourth grooves satisfy the aforementioned positional relationship with the first and second grooves, and by spacing the third and fourth grooves from the first and second grooves, the negative pressure generated in areas where multiple grooves are close together is reduced. Furthermore, the staggered arrangement of the first and second grooves with the third and fourth grooves results in a more compact groove layout, which is beneficial for miniaturizing the hydrodynamic bearing.

[0013] In one possible implementation, the third and fourth grooves are located on the same surface as the first and second grooves, and their adjacent ends are connected. By placing the third and fourth grooves on the same surface as the first and second grooves, and ensuring that their adjacent ends are connected, it is beneficial for the medium to generate greater dynamic pressure, thus supporting the stable levitation of the central shaft.

[0014] In one possible implementation, the two adjacent ends of the first and second grooves are connected. By connecting the adjacent ends of the first and second grooves, the medium can generate greater dynamic pressure in both the first and second grooves, which is beneficial for the stable levitation of the central axis.

[0015] In one possible implementation, the two adjacent ends of the first and second trenches are spaced apart, and the spaced region between the two adjacent ends of the first and second trenches has a groove, which is spaced apart from both the first and second trenches, and forms a portion of the connecting flow channel. By spaced the groove from both the first and second trenches, it is beneficial to reduce the negative pressure generated by the medium at the adjacent ends of the first and second trenches. By forming a portion of the connecting flow channel with the groove, the dynamic pressure at this portion of the connecting flow channel is increased, which is beneficial to increasing the dynamic pressure between the adjacent ends of the first and second flow channels.

[0016] In one possible implementation, the shape of the groove is axially symmetrical about a straight line parallel to the axial direction of the bearing. By making the shape of the groove axially symmetrical about a straight line parallel to the axial direction of the bearing, the groove can increase the dynamic pressure approximately the same when the bearing rotates clockwise or counterclockwise in the circumferential direction, ensuring bidirectional rotation of the dynamic pressure bearing.

[0017] In one possible implementation, the number of grooves corresponding to a single connecting channel is at least two, and the at least two grooves are arranged in an array in the axial and / or circumferential directions of the bearing. By arranging the at least two grooves in an array in the axial and / or circumferential directions of the bearing, the distribution of the at least two grooves is more uniform and regular, which helps to ensure the lifting capacity of the at least two grooves for dynamic pressure.

[0018] In one possible implementation, the number of first grooves corresponding to a single first flow channel is at least two, and the at least two first grooves are arranged in an array along the axial direction of the bearing. The number of second grooves corresponding to a single second flow channel is the same as the number of first grooves corresponding to a single first flow channel. By arranging at least two first grooves in an array along the axial direction of the bearing, the arrangement of the at least two first grooves is more regular, which helps to simplify the setting of the first grooves and ensures that the structure of the first grooves can improve dynamic pressure. By making the number of second grooves corresponding to a single second flow channel the same as the number of first grooves corresponding to a single first flow channel, the dynamic pressure generated by the first flow channel and the second flow channel is comparable, which facilitates the setting of multiple first flow channels and multiple second flow channels to jointly improve dynamic pressure according to actual needs.

[0019] In one possible implementation, the first groove and the second groove are symmetrically arranged, and the axis of symmetry of the first groove and the second groove extends along the circumference of the bearing. By symmetrically arranging the first groove and the second groove, and with the axis of symmetry of the first groove and the second groove extending along the circumference of the bearing, the dynamic pressure near the first flow channel and the dynamic pressure near the second flow channel are made equivalent, further ensuring the stable suspension of the central shaft.

[0020] In one possible implementation, at least one of the inner wall of the bearing and the outer wall of the central shaft has a widening groove, which communicates with at least one of the first groove and the second groove, and is located on the side of the first groove and the second groove that are close to each other. By making the widening groove communicate with at least one of the first groove and the second groove, and by making the widening groove located on the side of the first groove and the second groove that are close to each other, a larger space is provided on the side of the first groove and the second groove that are close to each other to accommodate the medium. This allows the medium lost on the side of the first groove and the second groove that are close to each other to be replenished in a timely manner, which helps to ensure that the side of the first groove and the second groove that are close to each other has sufficient medium to support the levitation of the central shaft.

[0021] In one possible implementation, the widening groove is located at the two ends of the first and second trenches that are close to each other, and the widening groove is connected to both the first and second trenches. By placing the widening groove at the two ends of the first and second trenches that are close to each other, the widening groove is positioned close to the locations in the first and second trenches where negative pressure is likely to be generated, ensuring the widening groove's ability to replenish the medium in the first and second trenches. By making the widening groove connected to both the first and second trenches, the first and second trenches can be connected through a single widening groove, which simplifies the placement of the widening groove and allows for better flow of the medium within the first and second trenches, helping to prevent medium loss.

[0022] In one possible implementation, both the first and second grooves are located on the inner wall of the bearing, and the outer wall of the central shaft has an annular groove arranged circumferentially around the central shaft. The annular groove corresponds to the two adjacent ends of the first and second grooves. By having an annular groove on the outer wall of the central shaft, and the annular groove corresponding to the two adjacent ends of the first and second grooves, a larger space is provided near the adjacent ends of the first and second grooves to accommodate the medium. This allows the medium lost on the adjacent side of the first and second grooves to be replenished in a timely manner, which helps to ensure that the adjacent side of the first and second grooves has sufficient medium to support the levitation of the central shaft.

[0023] In one possible implementation, the central shaft has a flange at at least one end in its axial direction, and the first groove and the second groove are located on at least one of two opposing surfaces of the flange in the axial direction of the central shaft. By positioning the first groove and the second groove on at least one of two opposing surfaces of the flange in the axial direction of the central shaft, the medium generates greater dynamic pressure on the first surface and / or the second surface during the operation of the hydrodynamic bearing, which is beneficial to improving the axial support capacity of the central shaft and enhancing the stability of the hydrodynamic bearing operation.

[0024] Secondly, this application also provides a motor device, including a hydrodynamic bearing and a motor as described in any embodiment of the first aspect, wherein at least one of the bearing and the central shaft of the motor and the hydrodynamic bearing is connected. The beneficial effects in this embodiment are similar to those in the above embodiments, and will not be repeated here. Attached Figure Description

[0025] Figure 1 is a structural schematic diagram of the hydrodynamic bearing provided in the embodiment of this application;

[0026] Figure 2 is a cross-sectional view of the bearing at point AA in the embodiment shown in Figure 1;

[0027] Figure 3 is a cross-sectional view of the hydrodynamic bearing at BB in the embodiment shown in Figure 1;

[0028] Figure 4 is a cross-sectional view of a bearing with a groove having varying depth according to an embodiment of this application;

[0029] Figure 5 is a cross-sectional view of a bearing with a groove having varying width according to an embodiment of this application;

[0030] Figure 6 is a front view of the central axis with grooves provided in an embodiment of this application;

[0031] Figure 7 is a cross-sectional view of a bearing with a third groove and a fourth groove provided in an embodiment of this application;

[0032] Figure 8 is a cross-sectional view of a bearing with grooves provided in an embodiment of this application;

[0033] Figure 9 is a cross-sectional view of a bearing with at least two grooves arranged circumferentially according to an embodiment of this application.

[0034] Figure 10 is a cross-sectional view of a bearing with at least two grooves arranged axially according to an embodiment of this application;

[0035] Figure 11 is a cross-sectional view of a bearing having at least two first grooves and at least two second grooves according to an embodiment of this application;

[0036] Figure 12 is a schematic diagram of the structure of the central shaft with an annular groove provided in an embodiment of this application;

[0037] Figure 13 is a schematic diagram of the structure of the central shaft with flange provided in the embodiment of this application;

[0038] Figure 14 is a system schematic diagram of the motor device provided in the embodiments of this application. Detailed Implementation

[0039] The embodiments of this application are described below with reference to the accompanying drawings.

[0040] For ease of understanding, the English abbreviations and related technical terms used in the embodiments of this application will be explained and described below.

[0041] It should be understood that the described embodiments are merely some, not all, of the embodiments in this application. All other embodiments obtained by those skilled in the art based on the embodiments in this application without inventive effort are within the scope of protection of this application.

[0042] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The singular forms “a,” “the,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0043] It should be understood that the term "and / or" used in this document is merely a description of the same field in the related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, and B alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0044] Depending on the context, the word "if" as used herein can be interpreted as "when," "when," "in response to determination," or "in response to detection." Similarly, depending on the context, the phrase "if determination" or "if detection (of the stated condition or event)" can be interpreted as "when determination," "in response to determination," "when detection (of the stated condition or event)," or "in response to detection (of the stated condition or event)."

[0045] It should be understood that the terms "first," "second," etc., used in this application are for distinguishing purposes only and should not be construed as indicating or implying relative importance or order. "At least one" means "one or more."

[0046] In the description of this application, the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", "clockwise", "counterclockwise", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0047] In the description of this application, it should be noted that due to manufacturing or assembly errors, there may be slight angular deviations in the design that should be perpendicular or parallel. For example, a deviation within 15 degrees is also considered perpendicular or parallel as described in this embodiment.

[0048] The phrase "within the range" used in this application, unless otherwise specified, includes both endpoints of the range by default. For example, in the range of 1 to 5, it includes the values ​​1 and 5.

[0049] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation", "connection" and "joining" should be interpreted broadly, for example, they can be fixed connections, detachable connections, mating connections or integral connections; those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0050] It should be understood that in the description of this application, the terms "connection" and "connected" can refer to a mechanical connection or a physical connection. For example, "A connected to B" or "A connected to B" can mean that there are fastening components (such as screws, bolts, rivets, etc.) between A and B, or that A and B are in contact with each other and are difficult to separate.

[0051] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0052] Ball bearings typically consist of an inner ring, an outer ring, and balls. The balls are located between the inner and outer rings, and both the inner and outer rings have a small contact area with the balls, reducing the friction generated when the inner and outer rings rotate relative to each other. However, due to machining precision limitations, when there are dimensional deviations in the balls, poor contact between the balls and the inner and outer rings can occur. This can lead to ball runout between the inner and outer rings, causing noise and affecting the bearing's operational stability. Furthermore, with increasing operating time, the structural stability between the balls and the inner and outer rings further decreases, further reducing the overall operational stability of the ball bearing.

[0053] A hydrodynamic bearing typically consists of a central shaft, a bearing, and a medium. The medium, usually a fluid, is located between the central shaft and the bearing. During operation, the medium generates dynamic pressure to suspend the central shaft, preventing the central shaft and bearing from contacting each other. This reduces the friction generated when the central shaft and bearing rotate relative to each other, and avoids noise generation and mechanical wear caused by operation, thus ensuring the stability of the hydrodynamic bearing operation.

[0054] To generate sufficient dynamic pressure during the operation of a hydrodynamic bearing, dynamic pressure grooves are typically incorporated inside the bearing. The distribution direction of these grooves is similar to the rotation direction of the shaft and / or bearing to maximize dynamic pressure. When the hydrodynamic bearing rotates in one direction, the stress concentration area of ​​the dynamic pressure groove is located on one side of the groove, making the stress concentration area relatively stable. However, in some applications, bidirectional rotation of the hydrodynamic bearing is required. In this case, the dynamic pressure grooves are distributed in both clockwise and counterclockwise directions. This causes the stress concentration area in the groove to become a low-pressure area during clockwise rotation, and vice versa. The reduced medium in the low-pressure area leads to a decrease in the levitation support force of the low-pressure area on the shaft, making it easier for the shaft and bearing to come into contact, thus reducing the operational stability of the hydrodynamic bearing.

[0055] This application provides a dynamic pressure bearing 100. Referring to Figure 1, Figure 1 shows a schematic diagram of the structure of the dynamic pressure bearing 100 provided in this embodiment. The dynamic pressure bearing 100 includes a central shaft 20 and a bearing 10. The bearing 10 is sleeved on the outer periphery of the central shaft 20, and the bearing 10 and the central shaft 20 are spaced apart. The space between the bearing 10 and the central shaft 20 is used to accommodate a medium, which is typically a fluid. This medium provides buoyancy for the suspension of the central shaft 20. During the operation of the dynamic pressure bearing 100, the medium generates dynamic pressure, further ensuring the suspension of the central shaft 20. The medium ensures the stability of the position of the central shaft 20 relative to the bearing 10, avoids contact between the central shaft 20 and the bearing 10, helps reduce the friction between the central shaft 20 and the bearing 10, avoids noise generation and mechanical wear caused by operation, and ensures the operational stability of the dynamic pressure bearing 100.

[0056] Please refer to Figure 2, which is a cross-sectional view of the bearing 10 at point AA in the embodiment shown in Figure 1. A flow channel exists between the bearing 10 and the central shaft 20, within which the medium is located. The flow channel guides the flow direction of the medium and restricts its flow path. Specifically, the flow channel includes a first flow channel 30, a second flow channel 40, and a connecting flow channel 50. The connecting flow channel 50 connects the first flow channel 30 and the second flow channel 40, allowing the medium to flow between them. Please refer to Figure 3, which is a cross-sectional view of the hydrodynamic bearing 100 at point BB in the embodiment shown in Figure 1. The depth of the connecting flow channel 50 is less than the depth of the first flow channel 30 and the second flow channel 40, enabling the medium to generate dynamic pressure at the first flow channel 30 and the second flow channel 40 during the operation of the hydrodynamic bearing 100, thereby improving the levitation ability and stability of the central shaft 20.

[0057] Referring to Figure 2, during the operation of the hydrodynamic bearing 100, the central shaft 20 and / or bearing 10 rotate approximately clockwise (CW direction as shown in Figure 2) or counterclockwise (CCW direction as shown in Figure 2) along the circumference of bearing 10, such that the rotation direction of the central shaft 20 and / or bearing 10 is approximately perpendicular to the axial direction of bearing 10 (Z direction as shown in Figure 2). The conduction directions of the first flow channel 30 and the second flow channel 40 both form angles with the radial direction (X direction as shown in Figure 2) and the axial direction of bearing 10, so that the conduction directions of the first flow channel 30 and the second flow channel 40 both form angles with the rotation direction. This is beneficial for the medium to generate a large dynamic pressure near the first flow channel 30 and the second flow channel 40, ensuring that the dynamic pressure is sufficient to support the suspension of the central shaft 20.

[0058] Please refer to Figure 2. The conduction direction of the first flow channel 30 and the conduction direction of the second flow channel 40 are at an angle, so that the first flow channel 30 has one end close to the second flow channel 40 and the other end far away from it. The direction from the other end of the first flow channel 30 far away from the second flow channel 40 to the end of the first flow channel 30 close to the second flow channel 40 is similar to the rotation direction of the central shaft 20 and / or the bearing 10. This makes the medium converge toward the end of the first flow channel 30 close to the second flow channel 40 during the operation of the hydrodynamic bearing 100. The medium generates a large dynamic pressure near the side of the first flow channel 30 and the second flow channel 40 that are close to each other. The dynamic pressure generated by the first flow channel 30 and the second flow channel 40 can be positively superimposed to jointly support the suspension of the central shaft 20, thereby improving the suspension ability and stability of the central shaft 20.

[0059] In one possible implementation, please refer to Figure 2. The side of the first flow channel 30 and the second flow channel 40 that is close to each other is located on the side of the first flow channel 30 and the second flow channel 40 that is far apart, in the counterclockwise direction (CCW direction as shown in Figure 2). During the operation of the hydrodynamic bearing 100, the bearing 10 rotates clockwise, causing the medium to converge towards the two ends of the first flow channel 30 and the second flow channel 40 that are close to each other, thereby improving the levitation ability and stability of the central shaft 20.

[0060] Please refer to Figure 2. The first flow channel 30 and the second flow channel 40 are alternately arranged in the axial direction of the bearing 10 (Z direction as shown in Figure 2). The two first flow channels 30 on both sides of the second flow channel 40 in the axial direction of the bearing 10 are the upper first flow channel 31 and the lower first flow channel 32, respectively. The second flow channel 40 is located between the upper first flow channel 31 and the lower first flow channel 32. The second flow channel 40 has a first end 41 and a second end 42 that are opposite to each other in its conduction direction. The first end 41 is close to the upper first flow channel 31, and the second end 42 is close to the lower first flow channel 32, so that the two opposite ends of a single second flow channel 40 can collect the medium, thereby realizing the bidirectional rotation of the hydrodynamic bearing 100 in both clockwise and counterclockwise directions.

[0061] Please refer to Figure 2. When the bearing 10 rotates clockwise (as shown in Figure 2 in the CW direction), the medium collects at the two ends of the second flow channel 40 and the upper first flow channel 31 that are close to each other, and the medium flows out at the two ends of the second flow channel 40 and the lower first flow channel 32 that are close to each other. When the bearing 10 rotates counterclockwise (as shown in Figure 2 in the CCW direction), the medium flows out at the two ends of the second flow channel 40 and the upper first flow channel 31 that are close to each other, and the medium collects at the two ends of the second flow channel 40 and the lower first flow channel 32 that are close to each other. The dynamic pressure generated by the first flow channel 30 and the second flow channel 40 on the side where the medium converges can be positively superimposed to jointly support the suspension of the central shaft 20. The negative pressure generated by the first flow channel 30 and the second flow channel 40 on the side where the medium flows out can also be positively superimposed, causing the medium volume of the first flow channel 30 and the second flow channel 40 on the side where the medium flows out to decrease or even disappear. The dynamic pressure generated by the first flow channel 30 and the second flow channel 40 on the side where the medium flows out is insufficient to support the stable suspension of the central shaft 20. The central shaft 20 and the bearing 10 are even prone to collision on the side where the medium flows out, affecting the stability of the operation of the dynamic pressure bearing 100.

[0062] By setting the shape and size of the first flow channel 30 and the second flow channel 40, excessive loss of medium at the adjacent ends of the first flow channel 30 and the second flow channel 40 can be avoided, ensuring that a large dynamic pressure can be generated at all points in the first flow channel 30 and the second flow channel 40, thereby ensuring the stable suspension of the central shaft 20. The setting of the shape and size of the first flow channel 30 and the second flow channel 40 will be described in detail below with reference to Figures 4 and 5.

[0063] In one embodiment, please refer to FIG4, which shows a cross-sectional view of a bearing 10 with a groove 11 having a depth variation provided in the embodiments of this application. The side of the first flow channel 30 and the second flow channel 40 that is close to each other has a smaller depth than the side that is far away from each other. This reduces the negative pressure that can be generated on the side of the first flow channel 30 and the second flow channel 40 that is close to each other, and reduces the degree of reduction in the medium volume on the side of the first flow channel 30 and the second flow channel 40 that is close to each other. This is beneficial to ensure that the side of the first flow channel 30 and the second flow channel 40 that is close to each other has sufficient medium to support the suspension of the central shaft 20.

[0064] For example, referring to Figure 4, the two ends of the second flow channel 40 and the upper first flow channel 31 that are close to each other have a small depth, while the end of the upper first flow channel 31 that is far from the second flow channel 40 has a large depth. The two ends of the second flow channel 40 and the lower first flow channel 32 that are close to each other have a small depth, while the end of the lower first flow channel 32 that is far from the second flow channel 40 has a large depth. This makes the first end 41 and the second end 42 of the second flow channel 40 have a small depth, and the middle region of the second flow channel 40 has a larger depth than the first end 41 and the second end 42. This is beneficial to ensure the bidirectional rotation of the hydrodynamic bearing 100 in both clockwise (CW direction as shown in Figure 4) and counterclockwise (CCW direction as shown in Figure 4) directions, and to avoid a large negative pressure on the side of the second flow channel 40 and the first flow channel 30 that is close to each other, which would affect the stability of the operation of the hydrodynamic bearing 100.

[0065] In one embodiment, please refer to FIG5, which shows a cross-sectional view of a bearing 10 with a groove 11 having a varying width provided in this application embodiment. The side of the first flow channel 30 and the second flow channel 40 that is close to each other has a larger width than the side that is far away from each other, so that the side of the first flow channel 30 and the second flow channel 40 that is close to each other has a larger space to accommodate the medium. When a negative pressure is generated on the side of the first flow channel 30 and the second flow channel 40 that is close to each other, the medium lost on the side of the first flow channel 30 and the second flow channel 40 that is close to each other can be replenished in time, reducing the degree of reduction in the medium volume on the side of the first flow channel 30 and the second flow channel 40 that is close to each other. This is beneficial to ensure that the side of the first flow channel 30 and the second flow channel 40 that is close to each other has sufficient medium to support the suspension of the central shaft 20.

[0066] For example, referring to Figure 5, the two ends of the second flow channel 40 and the upper first flow channel 31 that are close to each other have a large width, while the end of the upper first flow channel 31 that is far from the second flow channel 40 has a small width. The two ends of the second flow channel 40 and the lower first flow channel 32 that are close to each other have a large width, while the end of the lower first flow channel 32 that is far from the second flow channel 40 has a small width. This makes the first end 41 and the second end 42 of the second flow channel 40 have a large width, and the middle region of the second flow channel 40 has a smaller width than the first end 41 and the second end 42. This is beneficial to ensure the bidirectional rotation of the hydrodynamic bearing 100 in both clockwise (CW direction as shown in Figure 5) and counterclockwise (CCW direction as shown in Figure 5) directions, and to avoid a large negative pressure on the side of the second flow channel 40 and the first flow channel 30 that is close to each other, which would affect the stability of the operation of the hydrodynamic bearing 100.

[0067] It is understandable that the side of the first flow channel 30 and the second flow channel 40 that are close to each other can have a small depth and a large width at the same time, so that the negative pressure generated on the side of the first flow channel 30 and the second flow channel 40 that are close to each other can be reduced and the medium can be replenished in time. That is, the side of the first flow channel 30 and the second flow channel 40 that are close to each other always has enough medium to support the central shaft 20 to suspend, which is beneficial to ensuring the stability of the operation of the hydrodynamic bearing 100.

[0068] This application provides a hydrodynamic bearing 100, which includes a central shaft 20 and a bearing 10 sleeved on the outer periphery of the central shaft 20. The spacer region between the bearing 10 and the central shaft 20 has a first flow channel 30, a second flow channel 40, and a connecting flow channel 50 for distributing a medium. The connecting flow channel 50 connects the first flow channel 30 and the second flow channel 40, and the depth of the connecting flow channel 50 is less than the depth of the first flow channel 30 and the second flow channel 40, so that the hydrodynamic bearing 100 can generate dynamic pressure during operation, thereby suspending the central shaft 20. The conduction directions of the first flow channel 30 and the second flow channel 40 are both at angles to the radial and axial directions of the bearing 10, and there is an angle between the conduction directions of the first flow channel 30 and the second flow channel 40, so that the medium generates a large dynamic pressure near the side of the first flow channel 30 and the second flow channel 40 that are close to each other, and the dynamic pressure generated by the first flow channel 30 and the second flow channel 40 can be positively superimposed to jointly support the suspension of the central shaft 20. By alternating the first flow channel 30 and the second flow channel 40 in the axial direction of the bearing 10, the hydrodynamic bearing 100 can rotate bidirectionally in both clockwise and counterclockwise directions.

[0069] The side of the first flow channel 30 that is close to the second flow channel 40 has a smaller depth than the side that is farther away from the first flow channel 30 and the second flow channel 40, which reduces the negative pressure generated on the side where the first flow channel 30 and the second flow channel 40 are close; and / or, the side of the first flow channel 30 and the second flow channel 40 that is close to the first flow channel 30 and the second flow channel 40 has a larger width than the side that is farther away, which allows the medium lost on the side where the first flow channel 30 and the second flow channel 40 are close to the first flow channel 30 and the second flow channel 40 are close to the first flow channel 30 and the second flow channel 40 to be replenished in time. Both of these factors help to reduce the reduction in the medium volume on the side where the first flow channel 30 and the second flow channel 40 are close to the first flow channel 30 and the second flow channel 40 are close to the first flow channel 30 and the second flow channel 40 are close to the first flow channel 30 and the second flow channel 40 to have sufficient medium to support the suspension of the central shaft 20, thereby ensuring the stability of the operation of the hydrodynamic bearing 100.

[0070] In one possible implementation, referring to Figure 2, the inner wall of the bearing 10 and the outer wall of the central shaft 20 enclose the area between the bearing 10 and the central shaft 20. At least one of the inner wall of the bearing 10 and the outer wall of the central shaft 20 has a groove 11, which restricts the flow of the medium between the bearing 10 and the central shaft 20, thus forming a first flow channel 30 and a second flow channel 40. By setting the groove 11 to construct the first flow channel 30 and the second flow channel 40, the arrangement of the first flow channel 30 and the second flow channel 40 is simplified, the spacing between the bearing 10 and the central shaft 20 is guaranteed, and the dynamic pressure bearing 100 is miniaturized. Furthermore, by adjusting the setting position, shape, and size of the groove 11, the flow of the medium can be controlled to meet different application requirements.

[0071] Please refer to Figure 2. The groove includes a first groove 111 and a second groove 112. The first groove 111 and the second groove 112 form a first flow channel 30 and a second flow channel 40, respectively. The extension direction of the first groove 111 and the extension direction of the second groove 112 are both at an angle to the radial direction (X direction as shown in Figure 2) and the axial direction (Z direction as shown in Figure 2) of the bearing 10. There is also an angle between the extension direction of the first groove 111 and the extension direction of the second groove 112, so that the first flow channel 30 and the second flow channel 40 formed by the first groove 111 and the second groove 112 satisfy the angular relationship, ensuring that the first flow channel 30 and the second flow channel 40 formed by the first groove 111 and the second groove 112 can generate a large dynamic pressure. The number of first grooves 111 is at least two, and the number of second grooves 112 is at least one. The at least two first grooves 111 are located on both sides of the second grooves 112 in the axial direction of the bearing 10, so that the two opposite ends of the second grooves 112 are close to the first grooves 111. The medium can be collected on the side of the two first grooves 111 and the second grooves 112 that are close to each other, so as to realize the bidirectional rotation of the hydrodynamic bearing 100.

[0072] Please refer to Figure 2. At least two first grooves 111 and at least one second groove 112 are on the inner wall of the bearing 10. Alternatively, please refer to Figure 6, which shows a front view of the central shaft 20 with grooves 11 provided in the embodiment of this application. At least two first grooves 111 and at least one second groove 112 are on the outer wall of the central shaft 20, so that the first grooves 111 and the second grooves 112 are located on the same surface. This simplifies the arrangement of the first grooves 111 and the second grooves 112 and makes the dynamic pressure generated by the first flow channel 30 and the second flow channel 40 formed by the first grooves 111 and the second grooves 112 have a better superposition effect during the operation of the dynamic pressure bearing 100, supporting the stable suspension of the central shaft 20.

[0073] Please refer to Figures 2 and 6. When the bearing 10 rotates clockwise (CW direction as shown in Figures 2 and 6) or counterclockwise (CCW direction as shown in Figures 2 and 6) in the circumferential direction, the medium collects at one end of the second groove 112 and flows out at the other end, causing the medium volume near the other end of the second groove 112 to decrease or even disappear, forming a large negative pressure, which affects the stable suspension of the central shaft 20. Similarly, by setting the shape and size of the first groove 111 and the second groove 112, the shape and size of the first flow channel 30 and the second flow channel 40 can be controlled, which can prevent the medium from flowing out too much at the ends of the first groove 111 and the second groove 112 that are close to each other, and ensure that a large dynamic pressure can be generated at all points in the first groove 111 and the second groove 112, thereby ensuring the stable suspension of the central shaft 20. The shape and size of the first groove 111 and the second groove 112 will be described in detail below with reference to Figures 4 and 5.

[0074] In one embodiment, referring to Figure 4, the side of the first groove 111 and the second groove 112 that is close together has a smaller depth than the side that is far apart. This reduces the negative pressure generated on the side of the first groove 111 and the second groove 112 that is close together, which helps to ensure that the side of the first groove 111 and the second groove 112 that is close together has sufficient medium to support the suspension of the central shaft 20. For example, the depth of the end of the first groove 111 that is close together with the second groove 112 is 0 to 1 / 3 times the depth of the end of the first groove 111 that is far apart with the second groove 112. This allows the depth variation of the first groove 111 in its extension direction to be reasonably set, ensuring a large depth difference between the end of the first groove 111 that is close together with the second groove 112 and the end that is far apart with the first groove 111 that is far apart with the second groove 112. This results in a smaller negative pressure generated on the end of the first groove 111 that is close together with the second groove 112, ensuring that the first groove 111 has sufficient medium to support the suspension of the central shaft 20. It is understandable that when the second groove 112 has the first groove 111 on both sides of the bearing 10 in the axial direction (Z direction as shown in Figure 4), the depth of the two ends of the second groove 112 in the extension direction of the second groove 112 can be 0 to 1 / 3 times the depth of its middle region, so as to ensure that there is enough medium in the second groove 112 to support the suspension of the central shaft 20.

[0075] For example, please refer to Figure 2. The depth of the end of the first groove 111 that is close to the second groove 112 is 0, and the depth of the end of the second groove 112 that is close to the first groove 111 is also 0. That is, the two ends of the first groove 111 and the second groove 112 that are close to each other are spaced apart. This simplifies the structural arrangement of the two ends of the first groove 111 and the second groove 112 that are close to each other. It avoids the need to set the first groove 111 and the second groove 112 as stepped grooves to meet the above-mentioned depth changes. At the same time, it also minimizes the amount of negative pressure that can be generated on the side of the first groove 111 and the second groove 112 that are close to each other. This is beneficial to ensure that both the first groove 111 and the second groove 112 have sufficient medium to support the suspension of the central shaft 20.

[0076] In one embodiment, referring to FIG5, at least one of the inner wall of the bearing 10 and the outer wall of the central shaft 20 has a widening groove 13. The widening groove 13 is located on the same surface as the first groove 111 and the second groove 112, which helps to simplify the setting of the widening groove 13. The widening groove 13 communicates with at least one of the first groove 111 and the second groove 112, so that the medium flows between the widening groove 13 and the first groove 111 and / or between the widening groove 13 and the second groove 112, which helps to increase the accommodating space of the first groove 111 and / or the second groove 112 for the medium. The widening groove 13 is located on the side where the first groove 111 and the second groove 112 are close together, so that the side where the first groove 111 and the second groove 112 are close together has a larger space to accommodate the medium. When a negative pressure is generated on the side where the first groove 111 and the second groove 112 are close together, the medium lost on the side where the first groove 111 and the second groove 112 are close together can be replenished in time, reducing the degree of reduction in the medium volume on the side where the first flow channel 30 and the second flow channel 40 are close together. This is beneficial to ensure that the side where the first groove 111 and the second groove 112 are close together has enough medium to support the suspension of the central shaft 20.

[0077] For example, referring to Figure 5, the widening groove 13 is located at the two ends of the first groove 111 and the second groove 112 close to each other. This ensures that the widening groove 13 is positioned close to the locations in the first groove 111 and the second groove 112 where negative pressure is easily generated, thus guaranteeing the ability of the widening groove 13 to replenish the medium in the first groove 111 and the second groove 112. The widening groove 13 is connected to both the first groove 111 and the second groove 112, allowing them to be connected through a single widening groove 13. This simplifies the placement of the widening groove 13 and allows for better flow of the medium in the first groove 111 and the second groove 112, further preventing medium loss. All of these factors contribute to ensuring that the first groove 111 and the second groove 112 have sufficient medium to support the suspension of the central shaft 20.

[0078] In one possible implementation, please refer to FIG7, which shows a cross-sectional view of a bearing 10 with a third groove 113 and a fourth groove 114 provided in this embodiment of the application. The grooves 11 include a first groove 111, a second groove 112, a third groove 113, and a fourth groove 114. The first groove 111 and the second groove 112 are alternately arranged in the axial direction of the bearing 10 (Z direction as shown in FIG7), and the third groove 113 and the fourth groove 114 are alternately arranged in the axial direction of the bearing 10 (Z direction as shown in FIG7). The third groove 113 and the fourth groove 114 are both located on the same side of the first groove 111 and the second groove 112 in the circumferential direction of the bearing 10, which increases the number of grooves 11 and improves the dynamic pressure that the dynamic pressure bearing 100 can generate. At the same time, the multiple grooves 11 are distributed in the circumferential direction of the bearing 10, so that the dynamic pressure generated by the multiple grooves 11 can be superimposed, thereby improving the support capacity of the medium for the central shaft 20.

[0079] Please refer to Figure 7. The third groove 113 and the second groove 112 are parallel, and the fourth groove 114 and the first groove 111 are parallel. This arrangement of the third groove 113 and the second groove 112 and the fourth groove 114 and the first groove 111 results in a smaller negative pressure in the interval between the third groove 113 and the second groove 112, and a smaller negative pressure in the interval between the fourth groove 114 and the first groove 111. This avoids the generation of large negative pressure in the areas where multiple grooves 11 are close to each other, and ensures that multiple grooves 11 can generate sufficient dynamic pressure. Furthermore, the arrangement of multiple grooves 11 is more regular, which helps to simplify the setting of multiple grooves 11. The two ends of the third groove 113 and the fourth groove 114 that are close to each other correspond to the end of the second groove 112 that is away from the first groove 111, so that in the axial direction of the bearing 10, the second groove 112 and the third groove 113 are approximately at the same height, and the fourth groove 114 is located on the side of the second groove 112 that is away from the first groove 111. It can be understood that the two ends of the third groove 113 and the fourth groove 114 that are close to each other correspond to the area near the end of the second groove 112 that is away from the first groove 111.

[0080] By arranging the first groove 111, the second groove 112, the third groove 113, and the fourth groove 114 in the above-mentioned arrangement, the first groove 111 and the second groove 112 are staggered with the third groove 113 and the fourth groove 114 along the circumferential direction of the bearing 10. This makes full use of the space on the outer wall of the central shaft 20 and / or the inner wall of the bearing 10, making the arrangement of the grooves 11 more compact. This increases the number of grooves 11 that can be provided in the hydrodynamic bearing 100, which is beneficial for the medium to generate greater dynamic pressure between the central shaft 20 and the bearing 10 during the operation of the hydrodynamic bearing 100. Alternatively, when the number of grooves 11 that can be provided in the hydrodynamic bearing 100 is fixed, the axial length of the bearing 10 can be reduced, thereby achieving miniaturization of the hydrodynamic bearing 100.

[0081] Please refer to Figure 7. The second groove 112 and the third groove 113 are arranged in parallel. The third groove 113 is located on one side of the second groove 112 in the circumferential direction of the bearing 10, and the second groove 112 and the third groove 113 are approximately at the same height. This allows the medium to collect at the end of the second groove 112 near the first groove 111 when the bearing 10 rotates clockwise in the circumferential direction (CW direction as shown in Figure 7). The medium also collects at the end of the third groove 113 away from the fourth groove 114, so that the dynamic pressure generated by the second groove 112 and the dynamic pressure generated by the third groove 113 can be superimposed to jointly support the stable suspension of the central shaft 20.

[0082] Referring to Figure 7, the number of first grooves 111 can be at least two. Second grooves 112 are arranged in a one-to-one correspondence with the first grooves 111. Two adjacent first grooves 111 are arranged parallel to each other in the circumferential direction of the bearing 10. A third groove 113 is located in the interval region between two adjacent first grooves 111, and the third groove 113 is spaced apart from both the first groove 111 and the second groove 112. This results in a large interval region between adjacent first grooves 111, and the negative pressure generated in this interval region is small, preventing large negative pressure from being generated within the dynamic pressure grooves 11. Simultaneously, by setting the first grooves 111, second grooves 112, third grooves 113, and fourth grooves 114 to satisfy the above arrangement relationship, the arrangement of multiple grooves 11 is more compact, ensuring that the dynamic pressure bearing 100 has a sufficient number of grooves 11 and can generate large dynamic pressure.

[0083] In one embodiment, referring to Figure 7, the first groove 111, the second groove 112, the third groove 113, and the fourth groove 114 are all on the inner wall of the bearing 10 or the outer wall of the central shaft 20, so that the dynamic pressure generated in the first groove 111, the second groove 112, the third groove 113, and the fourth groove 114 has a good superposition effect, jointly supporting the stable suspension of the central shaft 20. The two ends of the third groove 113 and the fourth groove 114 that are close to each other can be connected, so that the medium can generate large dynamic pressure in both the third groove 113 and the fourth groove 114. Similarly, the two ends of the first groove 111 and the second groove 112 that are close to each other can also be connected, so that the medium can generate large dynamic pressure in both the first groove 111 and the second groove 112, which is beneficial to ensuring the support capacity of the medium for the central shaft 20.

[0084] In one possible implementation, please refer to FIG8, which shows a cross-sectional view of a bearing 10 with a groove 12 provided in the embodiment of this application. The two ends of the first groove 111 and the second groove 112 are spaced apart, which helps to reduce the negative pressure generated at the two ends of the first groove 111 and the second groove 112. However, during the operation of the dynamic pressure bearing 100, the dynamic pressure generated when the two ends of the first groove 111 and the second groove 112 are spaced apart is less than the dynamic pressure generated when the two ends of the first groove 111 and the second groove 112 are connected.

[0085] A groove 12 is provided in the space between the two adjacent ends of the first groove 111 and the second groove 112. The groove 12 is spaced apart from both the first groove 111 and the second groove 112 to avoid the groove 12 causing a large negative pressure at the adjacent ends of the first groove 111 and the second groove 112. The connecting channel 50 connects the first channel 30 formed by the first groove 111 and the second channel 40 formed by the second groove 112. The groove 12 forms a partial connecting channel 50, and this partial connecting channel 50 is located between the adjacent ends of the first channel 30 and the second channel 40. The groove 12 increases the dynamic pressure at this partial connecting channel 50, thereby increasing the dynamic pressure between the adjacent ends of the first channel 30 and the second channel 40.

[0086] In one embodiment, please refer to Figures 9 and 10. Figure 9 shows a cross-sectional view of a bearing 10 with at least two grooves 12 arranged circumferentially according to an embodiment of this application. Figure 10 shows a cross-sectional view of a bearing 10 with at least two grooves 12 arranged axially (in the Z direction as shown in Figures 9 and 10) according to an embodiment of this application. The number of grooves 12 corresponding to a single connecting flow channel 50 is at least two, so that the specific number of grooves 12 can be set according to actual needs, thereby controlling the degree of dynamic pressure increase near the two ends of the first flow channel 30 and the second flow channel 40. The at least two grooves 12 can be arranged in an array in the axial direction of the bearing 10, or the at least two grooves 12 can be arranged in an array in the axial direction of the bearing 10, so that the distribution of the at least two grooves 12 is more uniform and regular, which is beneficial to ensuring the ability of the at least two grooves 12 to increase dynamic pressure. It can be understood that the at least two grooves 12 can be arranged in an array both in the axial direction and in the circumferential direction of the bearing 10 to ensure the stable suspension of the central shaft 20.

[0087] In one embodiment, referring to Figures 8, 9, and 10, the bearing 10 rotates clockwise (CW direction as shown in Figures 8, 9, and 10) or counterclockwise (CCW direction as shown in Figures 8, 9, and 10) in the circumferential direction. The shape of the groove 12 is symmetrical about a line parallel to the axial direction of the bearing 10 (Z direction as shown in Figures 8, 9, and 10), such that the increase in dynamic pressure of the groove 12 is approximately equivalent when the bearing 10 rotates clockwise or counterclockwise in the circumferential direction, ensuring bidirectional rotation of the dynamic pressure bearing 100. Exemplarily, the shape of the groove 12 includes, but is not limited to, a circle or a rectangle.

[0088] In one possible implementation, please refer to Figure 11, which shows a cross-sectional view of a bearing 10 with at least two first grooves 111 and at least two second grooves 112 provided by an embodiment of this application. The number of first grooves 111 corresponding to a single first flow channel 30 is at least two, and the number of second grooves 112 corresponding to a single second flow channel 40 is at least two. This allows the medium to generate significant dynamic pressure near both the first flow channel 30 and the second flow channel 40, which is beneficial for ensuring that the dynamic bearing 100 has sufficient dynamic pressure to support the suspension of the central shaft 20. The number of second grooves 112 in a single second flow channel 40 can be the same as the number of first grooves 111 in a single first flow channel 30, making the dynamic pressure of the medium near the first flow channel 30 and the dynamic pressure near the second flow channel 40 approximately equivalent. This simplifies the setting and arrangement of the first grooves 111 and the second grooves 112, and facilitates setting different numbers of first flow channels 30 and second flow channels 40 according to actual needs, so that the dynamic bearing 100 has sufficient dynamic pressure to support the suspension of the central shaft 20.

[0089] In one embodiment, referring to Figure 11, the first groove 111 and the second groove 112 have the same shape and size, which further improves the regularity of the first groove 111 and the second groove 112 and simplifies the setting and arrangement of the first groove 111 and the second groove 112; at the same time, the dynamic pressure near the first flow channel 30 and the dynamic pressure near the second flow channel 40 are comparable, which helps to ensure the stability of the dynamic pressure at various points in the dynamic pressure bearing 100, thereby ensuring the stable suspension of the central shaft 20.

[0090] In one embodiment, referring to FIG11, at least two first grooves 111 and at least two second grooves 112 are arranged in an array along the axial direction of the bearing 10 (Z direction as shown in FIG11), making the arrangement of at least two first grooves 111 and at least two second grooves 112 more regular, which is beneficial to ensuring the lifting capacity of at least two first grooves 111 and at least two second grooves 112 for dynamic pressure, and further ensuring the stable suspension of the central shaft 20.

[0091] Please refer to Figure 11. At least two first grooves 111 and at least two second grooves 112 are symmetrically arranged. The axis of symmetry of the first grooves 111 and the second grooves 112 extends along the circumference of the bearing 10, so that the dynamic pressure of the medium near the first flow channel 30 formed by the first groove 111 is equivalent to the dynamic pressure near the second flow channel 40 formed by the second groove 112, which further ensures the stable suspension of the central shaft 20.

[0092] In one possible implementation, please refer to Figures 2 and 12. Figure 12 shows a schematic diagram of the structure of a central shaft 20 with an annular groove 21 provided in the embodiment of this application. The first groove 111 and the second groove 112 are both located on the inner wall of the bearing 10. The outer wall of the central shaft 20 has an annular groove 21. The annular groove 21 is arranged around the circumference of the central shaft 20 to increase the accommodating space of the medium. The two ends of the annular groove 21 that are close to the first groove 111 and the second groove 112 are opposite to each other, so that the setting position of the annular groove 21 is close to the position where the first groove 111 and the second groove 112 are prone to generate negative pressure, thus ensuring the replenishment capacity of the annular groove 21 for the medium in the first groove 111 and the second groove 112. When a negative pressure is generated near the end of the first flow channel 30 and the second flow channel 40 formed by the first groove 111 and the second groove 112, the medium lost at the end of the first groove 111 and the second groove 112 can be replenished in time, reducing the reduction in the medium volume at the end of the first flow channel 30 and the second flow channel 40, and further ensuring that the end of the first groove 111 and the second groove 112 has sufficient medium to support the suspension of the central shaft 20.

[0093] In one possible implementation, please refer to FIG13, which shows a schematic diagram of the structure of a central shaft 20 with a flange 22 provided in the embodiment of this application. The central shaft 20 has a flange 22 at at least one end in its axial direction (Z direction as shown in FIG13), so that the central shaft 20 has a large diameter at the flange 22. The diameter of the central shaft 20 at the flange 22 is larger than the inner diameter of the bearing 10, so that the flange 22 can limit the height of the central shaft 20 in the axial direction of the bearing 10, which is beneficial to ensuring the stability of the position of the central shaft 20 relative to the bearing 10. The flange 22 has a first surface 221 and a second surface 222 facing away from each other in the axial direction of the central shaft 20. The first groove 111 and the second groove 112 are located on at least one of the first surface 221 and the second surface 222, so that the medium near the first groove 111 and the second groove 112 on the flange 22 can provide axial support force for the central shaft 20. When the central shaft 20 rotates clockwise (CW direction as shown in Figure 13) or counterclockwise (CCW direction as shown in Figure 13) along the circumference of the bearing 10, the medium can generate a large dynamic pressure near the central shaft 20, thereby ensuring the suspension of the central shaft 20 and improving the stability of the operation of the dynamic pressure bearing 100.

[0094] In one embodiment, referring to FIG13, the outer wall of the central shaft 20 and the first surface 221 and the second surface 222 of the flange 22 both have a first groove 111 and a second groove 112, such that the medium near the first groove 111 and the second groove 112 on the outer wall of the central shaft 20 provides radial support force for the central shaft 20, and the medium near the first groove 111 and the second groove 112 on the first surface 221 and the second surface 222 provides axial support force for the central shaft 20. The central shaft 20 is simultaneously subjected to radial and axial support forces, which is beneficial to ensure the stable suspension of the central shaft 20 and improve the operational stability of the hydrodynamic bearing 100.

[0095] In one embodiment, referring to FIG13, the diameter of the first surface 221 of the flange 22 is larger than the inner diameter of the bearing 10, and the diameter of the second surface 222 of the flange 22 is larger than the inner diameter of the bearing 10, so that both the first surface 221 and the second surface 222 of the flange 22 have a large area to provide the first groove 111 and the second groove 112. The first surface 221 and / or the second surface 222 of the flange 22 have at least two first grooves 111 and at least one second groove 112, and the at least two first grooves 111 and at least one second groove 112 are located on the same surface, so as to ensure that the medium can generate a large dynamic pressure near the first surface 221 and / or the second surface 222 during the rotation of the bearing 10, further ensuring the stable suspension of the central shaft 20 and improving the stability of the dynamic pressure bearing 100. Meanwhile, the extension direction of the first groove 111 and the extension direction of the second groove 112 are both approximately radial to the central axis 20, so as to ensure that the medium near the first groove 111 and the second groove 112 can provide axial support force for the central axis 20.

[0096] This application also provides a motor device 200. Please refer to Figures 1 and 14. Figure 14 shows a system schematic diagram of the motor device 200 provided in an embodiment of this application. The motor device 200 includes a dynamic pressure bearing 100 and a motor 201. The motor 201 is connected to at least one of the bearing 10 and the central shaft 20 of the dynamic pressure bearing 100. The motor 201 is used to provide power to the dynamic pressure bearing 100 so that the dynamic pressure bearing 100 can rotate clockwise and counterclockwise.

[0097] It is understood that the motor device 200 in this embodiment has the dynamic pressure bearing 100 in the above embodiments. Therefore, the motor device 200 in this embodiment has all the technical effects of the dynamic pressure bearing 100 in the above embodiments. Since the technical effects of the dynamic pressure bearing 100 have been fully explained in the above embodiments, they will not be repeated here.

[0098] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A hydrodynamic bearing, characterized in that, include: Bearing and central shaft, the bearing being sleeved on the outer circumference of the central shaft. The bearing and the central shaft have a first flow channel, a second flow channel, and a connecting flow channel. The first flow channel and the second flow channel are alternately arranged in the axial direction of the bearing. The connecting flow channel connects the first flow channel and the second flow channel. The depth of the connecting flow channel is less than the depth of the first flow channel and the depth of the second flow channel. The conduction direction of the first flow channel and the conduction direction of the second flow channel both have an angle with the radial and axial directions of the bearing. There is an angle between the conduction directions of the first flow channel and the conduction direction of the second flow channel. The side of the first flow channel and the second flow channel that is closer to each other has a smaller depth and / or a larger width than the side that is farther away from each other.

2. The hydrodynamic bearing according to claim 1, characterized in that, At least one of the inner wall of the bearing and the outer wall of the central shaft has a groove, the groove forming the first flow channel and the second flow channel.

3. The hydrodynamic bearing according to claim 2, characterized in that, The groove includes at least two first grooves and at least one second groove. The at least two first grooves are located on both sides of the second groove in the axial direction of the bearing. The extension directions of the first groove and the second groove are both at angles with the radial and axial directions of the bearing. There is an angle between the extension directions of the first groove and the extension directions of the second groove. The first groove and the second groove are both on the inner wall of the bearing or the outer wall of the central shaft. The first groove and the second groove respectively form the first flow channel and the second flow channel.

4. The hydrodynamic bearing according to claim 3, characterized in that, The depth of the end of the first trench that is close to the second trench is 0 to 1 / 3 times the depth of the other end that is far away.

5. The hydrodynamic bearing according to claim 3 or 4, characterized in that, The first groove and the second groove are alternately arranged in the axial direction of the bearing. The groove also includes a third groove and a fourth groove. The third groove and the fourth groove are located on the same side of the first groove and the second groove in the circumferential direction of the bearing. The third groove and the fourth groove are parallel to the second groove and the first groove, respectively. The two ends of the third groove and the fourth groove that are close to each other correspond to the end of the second groove that is away from the first groove.

6. The hydrodynamic bearing according to claim 5, characterized in that, The third and fourth grooves are located on the same surface as the first and second grooves, and the two ends of the third and fourth grooves that are close to each other are connected.

7. The hydrodynamic bearing according to any one of claims 3 to 6, characterized in that, The two ends of the first trench and the second trench that are close to each other are connected.

8. The hydrodynamic bearing according to any one of claims 3 to 6, characterized in that, The first groove and the second groove are spaced apart at their adjacent ends, and the spaced area between the adjacent ends of the first groove and the second groove has a groove. The groove is spaced apart from both the first groove and the second groove, and the groove forms part of the connecting flow channel.

9. The hydrodynamic bearing according to claim 8, characterized in that, The shape of the groove is symmetrical about a straight axis parallel to the axial direction of the bearing.

10. The hydrodynamic bearing according to claim 8 or 9, characterized in that, The number of grooves corresponding to a single connecting channel is at least two, and the at least two grooves are arranged in an array in the axial and / or circumferential directions of the bearing.

11. The hydrodynamic bearing according to any one of claims 3 to 10, characterized in that, The number of first grooves corresponding to a single first flow channel is at least two, and the at least two first grooves are arranged in an array along the axial direction of the bearing. The number of second grooves corresponding to a single second flow channel is the same as the number of first grooves corresponding to a single first flow channel.

12. The hydrodynamic bearing according to any one of claims 3 to 11, characterized in that, The first groove and the second groove are symmetrically arranged, and the axis of symmetry of the first groove and the second groove extends along the circumference of the bearing.

13. The hydrodynamic bearing according to any one of claims 3 to 12, characterized in that, At least one of the inner wall of the bearing and the outer wall of the central shaft has a widening groove, the widening groove communicating with at least one of the first groove and the second groove, and the widening groove being located on the side of the first groove and the second groove that are close to each other.

14. The hydrodynamic bearing according to claim 13, characterized in that, The widening groove is located at the two ends of the first groove and the second groove that are close to each other, and the widening groove is connected to both the first groove and the second groove.

15. The hydrodynamic bearing according to any one of claims 3 to 14, characterized in that, Both the first groove and the second groove are located on the inner wall of the bearing. The outer wall of the central shaft has an annular groove, which is arranged circumferentially around the central shaft. The annular groove corresponds to the two ends of the first groove and the second groove that are close to each other.

16. The hydrodynamic bearing according to any one of claims 3 to 15, characterized in that, The central shaft has a flange at at least one end in its axial direction, and the first groove and the second groove are located on at least one of two surfaces of the flange that are opposite each other in the axial direction of the central shaft.

17. A motor device, characterized in that, Includes the hydrodynamic bearing and motor as described in any one of claims 1 to 16, wherein the motor and at least one of the bearing and the central shaft of the hydrodynamic bearing are connected.

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