Composite sliding bearing, double-rotor adjustable-speed motor and lubricating method

Abstract

The invention relates to the technical field of bearings, and discloses a composite sliding bearing, a double-rotor adjustable-speed motor and a lubricating method, and the bearing integrates a first bearing bush assembly and a second bearing bush assembly which are used for supporting an inner rotor and an outer rotor into the same bearing seat. The first oil inlet path and the second oil inlet path independently lead to the two bearing bush assemblies, and the oil guide structures and the oil rings are arranged on the bearing bush assemblies and used for establishing oil films for lubricating the inner rotor and the outer rotor respectively. And a first oil return cavity and a second oil return cavity for collecting two paths of return oil respectively are arranged in the lower bearing seat, are communicated with each other and are converged into the same return oil outlet. The double-rotor speed regulation motor adopting the bearing is axially compact in structure, independent supporting and integrated lubrication of the double rotors are realized through a single bearing body, an external oil way is simplified, the bearing capacity is improved, and the rotating speed range is widened.

Description

Technical Field

[0001] This invention relates to the field of bearing technology, specifically to composite sliding bearings, dual-rotor speed-regulating motors, and lubrication methods. Background Technology

[0002] Dual-rotor speed-regulating motors, especially permanent magnet coupled speed-regulating motors, are highly efficient electromechanical energy conversion and speed regulation devices. Due to their compact structure, wide speed range, and high efficiency, they have demonstrated significant advantages in industrial energy-saving retrofitting fields such as fans and pumps. The core feature of this type of motor lies in its coaxial arrangement and relatively independent rotation of inner and outer rotors. The inner rotor typically carries the armature winding, while the outer rotor is fitted with permanent magnets. Stepless speed regulation of the output shaft is achieved by adjusting the relative speed difference (slip) between the two. This unique operating mechanism places stringent requirements on the design of the support system: the bearings must be able to simultaneously and stably support two coaxial rotating components with potentially different speeds and loads.

[0003] Currently, rolling bearings are commonly used as the support system in these dual-rotor motors. While rolling bearings offer advantages such as low friction, low starting torque, and high standardization, their dynamic load-bearing capacity and limiting speed are inherently limited by physical constraints (e.g., rolling element contact fatigue, cage strength, etc.). With the continuous increase in motor power density and speed, especially in high-power, high-speed applications, rolling bearings have become the primary bottleneck for system performance and reliability. Since both internal and external bearings directly bear the motor's electromagnetic torque and some of the unbalanced magnetic pull, they face challenges in terms of speed and load capacity; therefore, they also struggle to meet the requirements of higher operating conditions. This fundamentally restricts the development of dual-rotor permanent magnet speed-regulating motors towards higher power levels and wider speed ranges.

[0004] To push the performance limits of rolling bearings, the industry naturally considers using sliding bearings. Sliding bearings rely on a hydrodynamic oil film for non-contact support, theoretically offering higher limiting speeds, greater load-bearing capacity, and superior damping characteristics. However, simply applying sliding bearings to a dual-rotor structure presents significant engineering challenges:

[0005] Structural complexity and axial space conflict: While a hybrid arrangement of "external sliding bearing - internal rolling bearing" is relatively simple, from a mechanical transmission path analysis, the external sliding bearing needs to bear the load of the internal rotor and transmit it through the frame, while the internal rolling bearing needs to bear the load of the external rotor. The significant difference in support stiffness between the two can easily cause vibration coupling, making it a suboptimal mechanical design. Using an "external rolling bearing - internal sliding bearing" scheme, in principle, could make the force distribution more reasonable, but the oil supply, return, and sealing system of the internal sliding bearing needs to be arranged through the external rotor structure, resulting in an exceptionally complex overall structure and making assembly and maintenance extremely difficult.

[0006] The inherent drawbacks of a dual sliding bearing arrangement: The most straightforward approach is to configure separate sliding bearing assemblies for the inner and outer rotors. However, this would significantly increase the axial dimension of the motor, which is unacceptable in many applications with strict space constraints. Furthermore, two independent bearings mean two completely independent lubrication supply systems, return lines, and sealing devices are required. This not only significantly increases system complexity and manufacturing costs but also introduces more potential leakage points and higher maintenance requirements. The type of lubricant may need to be differentiated based on the different operating conditions of the inner and outer bearings, further complicating operation and management.

[0007] Therefore, there is a lack of existing bearing solutions that can balance high speed and high load capacity, compact structure, simplified lubrication system and easy installation and maintenance, so as to fully unleash the performance potential of dual rotor speed-regulating motors. Summary of the Invention

[0008] This invention provides a composite sliding bearing, a dual-rotor speed-regulating motor, and a lubrication method to solve the above-mentioned problems.

[0009] In a first aspect, the present invention provides a composite sliding bearing, comprising: A bearing housing, comprising a lower bearing housing and an upper bearing housing, wherein the lower bearing housing is provided with a first bearing bush mounting portion and a second bearing bush mounting portion; The first bearing assembly and the second bearing assembly are respectively installed in the first bearing mounting part and the second bearing mounting part, and are used to support the inner rotor and the outer rotor that are coaxially arranged respectively. The lubrication circuit includes a first oil inlet and a second oil inlet provided in the lower bearing housing, and an oil guiding structure provided on the first bearing assembly and the second bearing assembly; The first oil inlet passage is connected to the first bearing assembly, and the second oil inlet passage is connected to the second bearing assembly; The lower bearing housing is provided with a first oil return chamber and a second oil return chamber that are respectively connected to the first bearing assembly and the second bearing assembly. The first oil return chamber and the second oil return chamber are interconnected and have a common oil return outlet.

[0010] In one alternative implementation: The first bearing bush mounting part includes a first cavity formed by the lower bearing bush of the lower bearing seat and the upper bearing bush of the upper bearing seat; The second bearing mounting portion includes a second cavity formed by the lower bearing housing and the upper bearing housing.

[0011] In one alternative implementation: The oil guiding structure includes an oil inlet groove disposed on the first bearing assembly and the second bearing assembly, and an oil inlet groove port communicating with the oil inlet groove; Oil rings are respectively provided on the first bearing assembly and the second bearing assembly.

[0012] In one alternative implementation: Both the first and second bearing assemblies include an upper bearing and a lower bearing, which are fixed together by a connector. The upper bearing housing is provided with a positioning pin hole, and the upper bearing shell is provided with a corresponding positioning pin hole, so as to realize the circumferential positioning of the bearing shell assembly through the positioning pin.

[0013] In one alternative implementation: The bearing housing is provided with a viewing structure for observing the oil level inside the bearing assembly; and The bearing housing is provided with a temperature measuring hole for mounting a temperature measuring element; and The bearing housing is provided with a vibration measuring structure for mounting a vibration sensor; and The upper bearing housing is provided with a vent hole, and a venting device is installed at the vent hole; and The upper bearing housing is equipped with a lifting structure.

[0014] In one alternative embodiment, the first bearing assembly and the second bearing assembly are sliding bearing bearings, and their inner working surfaces are covered with a friction-reducing layer.

[0015] Secondly, the present invention also provides a dual-rotor speed-regulating motor, comprising: A composite sliding bearing, serving as both a first and a second sliding bearing; Base; The stator winding is fixed inside the frame; An inner rotor is rotatably disposed within the machine base; The outer rotor is coaxially sleeved outside the inner rotor and can rotate independently of the inner rotor; The first sliding bearing and the second sliding bearing are respectively installed at both axial ends of the machine base; the first bearing assembly of the first sliding bearing and the first bearing assembly of the second sliding bearing jointly support the inner rotor; The second bearing assembly of the first sliding bearing and the second bearing assembly of the second sliding bearing together support the outer rotor.

[0016] In one alternative embodiment, a sealing structure is further included, disposed between the inner rotor and the outer rotor, to prevent bearing lubricating oil from entering the cavity between the inner and outer rotors.

[0017] In one alternative embodiment, of the first and second sliding bearings, one is axially fixed relative to the machine base, while the other is allowed to float axially.

[0018] Thirdly, the present invention also provides a lubrication method for a dual-rotor speed-regulating motor, employing the aforementioned composite sliding bearing, the method comprising: Provide one fuel supply line and then split it into a first branch line and a second branch line; The first branch lubricating oil is directed to the first bearing assembly, and an oil film is formed between the first bearing assembly and the inner rotor shaft. The second branch lubricating oil is led to the second bearing assembly, and an oil film is formed between the second bearing assembly and the outer rotor bearing housing; Collect the return oil from the first bearing assembly and the second bearing assembly, and then discharge it after they are combined. Attached Figure Description

[0019] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 This is a front view of a composite sliding bearing according to an embodiment of the present invention; Figure 2 for Figure 1 A cross-sectional view along the AA direction; Figure 3 This is a cross-sectional view of the oil inlet section in a composite sliding bearing according to an embodiment of the present invention; Figure 4 This is a cross-sectional view of the temperature measuring part in a composite sliding bearing according to an embodiment of the present invention; Figure 5 This is a schematic diagram of the structure of the lower bearing housing in a composite sliding bearing according to an embodiment of the present invention; Figure 6 This is a schematic diagram of the oil return cavity in a composite sliding bearing according to an embodiment of the present invention; Figure 7 This is a schematic diagram of the upper bearing housing in a composite sliding bearing according to an embodiment of the present invention; Figure 8 This is a schematic diagram of the internal structure of the upper bearing housing in a composite sliding bearing according to an embodiment of the present invention; Figure 9 This is a schematic diagram of the structure of a composite sliding bearing bush assembly according to an embodiment of the present invention; Figure 10 This is a schematic diagram of the upper bearing structure in a composite sliding bearing according to an embodiment of the present invention; Figure 11This is a schematic diagram of the structure of the lower bearing in a composite sliding bearing according to an embodiment of the present invention; Figure 12 This is a schematic diagram of the structure of a dual-rotor speed-regulating motor according to an embodiment of the present invention.

[0021] Explanation of reference numerals in the attached figures: 11. Lower bearing housing; 111. Small bearing lower housing; 112. Large bearing lower housing; 12. Upper bearing housing; 121. Small bearing upper housing; 122. Large bearing upper housing; 13. Temperature measuring hole; 14. Exhaust hole; 15. Exhaust device; 16. Oil return hole; 17. Oil inlet hole; 18. Inspection hole; 19. Temperature probe hole; 20. Vibration measuring hole; 21. Lifting hole; 22. Lifting ring; 201. First bearing assembly; 202. Second bearing assembly; 31. Upper tile; 32. Lower tile; 33. First oil return chamber; 34. Second oil return chamber; 41. Oil inlet groove; 42. Oil inlet groove opening; 43. Oil ring; 51. Machine base; 52. Left bearing housing; 53. Right bearing housing; 61. Stator winding; 62. Inner rotor; 621. Inner rotor winding; 622. Shaft; 63. Outer rotor; 631. First bearing housing; 632. Support cylinder; 633. First permanent magnet; 634. Second permanent magnet; 635. Second bearing housing; 71. First sliding bearing; 72. Second sliding bearing; 81. First bearing isolator; 82. Second bearing isolator; 91. Slip ring; 92. Connecting disc; 93. Brush holder; 94. Protective cover. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] Dual-rotor speed-regulating motors, especially permanent magnet coupled speed-regulating motors, are highly efficient electromechanical energy conversion and speed regulation devices. Due to their compact structure, wide speed range, and high efficiency, they have demonstrated significant advantages in industrial energy-saving retrofitting fields such as fans and pumps. The core feature of this type of motor lies in its coaxial arrangement and relatively independent rotation of inner and outer rotors. The inner rotor typically carries the armature winding, while the outer rotor is fitted with permanent magnets. Stepless speed regulation of the output shaft is achieved by adjusting the relative speed difference (slip) between the two. This unique operating mechanism places stringent requirements on the design of the support system: the bearings must be able to simultaneously and stably support two coaxial rotating components with potentially different speeds and loads.

[0024] Currently, rolling bearings are commonly used as the support system in these dual-rotor motors. While rolling bearings offer advantages such as low friction, low starting torque, and high standardization, their dynamic load-bearing capacity and limiting speed are inherently limited by physical constraints (e.g., rolling element contact fatigue, cage strength, etc.). With the continuous increase in motor power density and speed, especially in high-power, high-speed applications, rolling bearings have become the primary bottleneck for system performance and reliability. Since both internal and external bearings directly bear the motor's electromagnetic torque and some of the unbalanced magnetic pull, they face challenges in terms of speed and load capacity; therefore, they also struggle to meet the requirements of higher operating conditions. This fundamentally restricts the development of dual-rotor permanent magnet speed-regulating motors towards higher power levels and wider speed ranges.

[0025] To push the performance limits of rolling bearings, the industry naturally considers using sliding bearings. Sliding bearings rely on a hydrodynamic oil film for non-contact support, theoretically offering higher limiting speeds, greater load-bearing capacity, and superior damping characteristics. However, simply applying sliding bearings to a dual-rotor structure presents significant engineering challenges: Structural complexity and axial space conflict: While a hybrid arrangement of "external sliding bearing - internal rolling bearing" is relatively simple, the external sliding bearing must bear the load of the internal rotor and transmit it through the frame, while the internal rolling bearing must bear the load of the external rotor. The significant difference in support stiffness between the two can easily lead to vibration coupling, making it less than optimal mechanical design. Using an "external rolling bearing - internal sliding bearing" scheme, in principle, could make the force distribution more reasonable, but the oil supply, return, and sealing systems of the internal sliding bearing must pass through the external rotor structure, resulting in an exceptionally complex overall structure and making assembly and maintenance extremely difficult.

[0026] The inherent drawbacks of a dual sliding bearing arrangement: The most straightforward approach is to configure separate sliding bearing assemblies for the inner and outer rotors. However, this would significantly increase the axial dimension of the motor, which is unacceptable in many applications with strict space constraints. Furthermore, two independent bearings mean two completely independent lubrication supply systems, return lines, and sealing devices are required. This not only significantly increases system complexity and manufacturing costs but also introduces more potential leakage points and higher maintenance requirements. The type of lubricant may need to be differentiated based on the different operating conditions of the inner and outer bearings, further complicating operation and management.

[0027] Therefore, there is a lack of existing bearing solutions that can balance high speed and high load capacity, compact structure, simplified lubrication system and easy installation and maintenance, so as to fully unleash the performance potential of dual rotor speed-regulating motors.

[0028] The following is combined Figures 1 to 12 The following describes embodiments of the present invention.

[0029] According to an embodiment of the present invention, a composite sliding bearing is provided, comprising a bearing housing, a first bearing assembly 201 and a second bearing assembly 202, and a lubrication oil passage. The bearing housing includes a lower bearing housing 11 and an upper bearing housing 12. The lower bearing housing 11 is provided with a first bearing mounting portion and a second bearing mounting portion. The first bearing assembly 201 and the second bearing assembly 202 are respectively mounted in the first bearing mounting portion and the second bearing mounting portion, for supporting an inner rotor 62 and an outer rotor 63 coaxially arranged, respectively. The lubrication oil passage includes a first oil inlet passage and a second oil inlet passage provided in the lower bearing housing 11, and an oil guiding structure provided on the first bearing assembly 201 and the second bearing assembly 202. The first oil inlet passage is connected to the first bearing assembly 201, and the second oil inlet passage is connected to the second bearing assembly 202. The lower bearing housing 11 is provided with a first oil return chamber 33 and a second oil return chamber 34, which are respectively connected to the first bearing assembly 201 and the second bearing assembly 202. The first oil return chamber 33 and the second oil return chamber 34 are interconnected and have a common oil return outlet.

[0030] The core of this composite sliding bearing lies in the high integration of two independent bearing bushes and their lubrication circuits, used to support coaxial dual rotors, into a unified bearing housing. Specifically, the bearing housing consists of a lower bearing housing 11 and an upper bearing housing 12 connected by bolts arranged on both sides of the bearing housing, forming a complete bearing housing. Inside the housing, a first bearing bush mounting part and a second bearing bush mounting part are integrally machined, arranged side by side along the bearing axis and having different inner diameters to respectively accommodate and position the first bearing bush assembly 201 and the second bearing bush assembly 202.

[0031] The first bearing assembly 201 and the second bearing assembly 202 are two independent cylindrical sliding bearings, installed inside corresponding mounting portions within the bearing housing. The first bearing assembly 201 has a smaller inner bore for engaging with the journal of the inner rotor 62 to form a first friction pair; the second bearing assembly 202 has a larger inner bore for engaging with the journal (or bearing housing) of the outer rotor 63 to form a second friction pair. The two bearing assemblies are coaxially fixed within the bearing housing.

[0032] The lubrication circuit is key to achieving dual-path independent lubrication in this invention. Inside the side wall of the lower bearing housing 11, a first oil inlet and a second oil inlet are machined, isolated from each other. The outlet of the first oil inlet leads to the first bearing bush mounting area and communicates with the oil guide structure provided on the first bearing bush assembly 201; correspondingly, the outlet of the second oil inlet leads to the second bearing bush mounting area and communicates with the oil guide structure provided on the second bearing bush assembly 202. The oil guide structure can be an oil groove formed on the inner surface of the bearing bush and an oil inlet 42 communicating with it, used to guide pressurized lubricating oil to the working surfaces of the bearing bush and the rotating shaft.

[0033] At the bottom of the lower bearing housing 11, a first oil return chamber 33 and a second oil return chamber 34, which are independent of each other, are cast or machined. The first oil return chamber 33 is located directly below the first bearing assembly 201 and is used to collect lubricating oil flowing out from the first friction pair; the second oil return chamber 34 is located directly below the second bearing assembly 202 and is used to collect lubricating oil flowing out from the second friction pair. The first oil return chamber 33 and the second oil return chamber 34 are not completely isolated; they are interconnected at the end of the bearing housing through a connecting channel, allowing the two oil return paths to merge. Finally, the merged lubricating oil is discharged from the bearing through a common oil return hole 16 opened on the lower bearing housing 11 and returns to the external oil tank.

[0034] This embodiment achieves independent support and lubrication of a dual-rotor system within a compact bearing housing through the aforementioned structure. Its lubrication circuit adopts an integrated design of "dual oil inlets, dual oil returns, and end-combination," requiring only one set of inlet and return oil pipe interfaces to meet the needs of both friction pairs. This greatly simplifies external oil circuit connections, reduces leakage risk, and significantly shortens the axial dimension of the bearing components, providing a solution for the application of dual-rotor motors in space-constrained environments.

[0035] In one embodiment, the first bearing mounting portion includes a first cavity formed by the small bearing lower seat 111 of the lower bearing seat 11 and the small bearing upper seat 121 of the upper bearing seat 12; the second bearing mounting portion includes a second cavity formed by the large bearing lower seat 112 of the lower bearing seat 11 and the large bearing upper seat 122 of the upper bearing seat 12.

[0036] In this embodiment, the structure inside the bearing housing for accommodating and positioning the bearing bush assembly is not a simple through hole, but a dedicated seat formed by the precise fitting of two upper and lower parts. Specifically, a first groove and a second groove are integrally machined or cast on the inner surface of the lower bearing housing 11. The outline of the first groove matches the shape of the lower half of the first bearing bush assembly 201, forming the small bearing bush lower seat 111 as referred to in this embodiment; the outline of the second groove matches the shape of the lower half of the second bearing bush assembly 202, forming the large bearing bush lower seat 112 as referred to in this embodiment. Correspondingly, a groove corresponding to the lower bearing housing 11 is also machined on the inner surface of the upper bearing housing 12. The portion that is vertically opposite to the small bearing bush lower seat 111 forms the small bearing bush upper seat 121 as referred to in this embodiment; the portion that is vertically opposite to the large bearing bush lower seat 112 forms the large bearing bush upper seat 122 as referred to in this embodiment.

[0037] After the upper bearing housing 12 and the lower bearing housing 11 are fastened together with bolts, the lower small bearing housing 111 and the upper small bearing housing 121 together form a complete first cavity. The shape and size of this first cavity are designed so that the first bearing assembly 201 can be installed inside it, thereby accurately accommodating and fixing the first bearing assembly 201, forming the first bearing mounting part. Similarly, the lower large bearing housing 112 and the upper large bearing housing 122 together form a second cavity, which is used to accurately accommodate and fix the second bearing assembly 202, forming the second bearing mounting part.

[0038] This structure, where the upper and lower seats enclose a cavity, ensures that the bearing assembly is securely and precisely installed within the bearing housing, providing excellent radial positioning accuracy and load-bearing stability. Simultaneously, the separate upper and lower seat design facilitates the installation, adjustment, and subsequent maintenance and replacement of the bearing assembly.

[0039] The lower bearing housing 11 is provided with two oil inlet holes 17, which are used to supply oil to the first oil inlet and the second oil inlet respectively.

[0040] In one embodiment, the oil guiding structure includes an oil inlet groove 41 disposed on the first bearing assembly 201 and the second bearing assembly 202, and an oil inlet port 42 communicating with the oil inlet groove 41; an oil ring 43 is disposed on the first bearing assembly 201 and the second bearing assembly 202 respectively.

[0041] On the inner working surfaces of both the first bearing assembly 201 and the second bearing assembly 202, an annular oil inlet groove 41 is provided circumferentially. This oil inlet groove 41 serves as the main temporary storage and distribution channel for lubricating oil. At the bottom of the oil inlet groove 41 (i.e., on the side near the inner wall of the bearing assembly), a number of oil inlet openings 42 are provided circumferentially at intervals, which directly connect the oil inlet groove 41 to the inner surface of the bearing.

[0042] To achieve more efficient lubricant delivery and oil film establishment, this embodiment provides oil rings 43 on the first bearing assembly 201 and the second bearing assembly 202, respectively. Specifically, each oil ring 43 is installed in a specific annular groove of its respective bearing assembly. A portion of the oil ring 43 is immersed in the lubricant collected by the oil inlet groove 41. When the rotor journal supported by it rotates, it will drive the oil ring 43 to rotate together (or the oil ring 43 will rotate under the action of friction). The rotating oil ring 43 continuously "carries" lubricant from the oil inlet groove 42 and coats it into the gap between the working surfaces of the bearing and the rotating shaft, thereby efficiently promoting the formation of a hydrodynamic oil film.

[0043] In one embodiment, both the first bearing assembly 201 and the second bearing assembly 202 include an upper bearing 31 and a lower bearing 32, which are fixed by a connector; the upper bearing seat 12 is provided with a positioning pin hole, and the upper bearing 31 is provided with a corresponding positioning pin hole, so as to realize the circumferential positioning of the bearing assembly by the positioning pin.

[0044] In this embodiment, both the first bearing assembly 201 and the second bearing assembly 202 adopt a split structure, each consisting of an upper bearing shell 31 and a lower bearing shell 32 assembled together. The inner surfaces of the upper bearing shell 31 and the lower bearing shell 32 together form a complete circular bearing hole. The two are fastened together by several connectors (such as bolts and nuts) to form a rigid integral bearing assembly. This split structure facilitates the machining, assembly, and maintenance and replacement of the bearing shells after wear.

[0045] To ensure that the bearing bush assembly does not rotate circumferentially within the mounting cavity of the bearing housing, and thus to guarantee precise alignment of structures such as the oil inlet groove 41 with the oil passage interface on the bearing housing, this embodiment employs a dedicated circumferential positioning structure. Specifically, positioning pin holes are machined at corresponding positions on the upper bearing housing 12, such as the tops of its small bearing bush upper seat 121 and large bearing bush upper seat 122. Correspondingly, coaxial positioning pin holes a are also machined at corresponding positions on the back of the upper bearing bush 31 of each bearing bush assembly. Figure 10 (As shown). During assembly, one end of a locating pin b is inserted into the locating pin hole of the upper bearing seat 12, and the other end is inserted into the locating pin hole a of the upper bearing shell 31, thereby firmly fixing the upper bearing shell 31 (and thus the entire bearing shell assembly) in the circumferential direction and preventing it from rotating.

[0046] In one embodiment, the bearing housing is provided with an inspection structure for observing the oil level inside the bearing assembly, such as two inspection holes 18 on the upper bearing housing 12, and correspondingly, an inspection window c corresponding to the inspection holes 18 on the upper bearing shell 31. The bearing housing is provided with two temperature measuring holes 13 for mounting temperature measuring elements, and correspondingly, a temperature measuring probe hole 19 connected to the temperature measuring holes 13 is provided on the lower bearing shell 32 for measuring the temperature of the bearing assembly through the temperature measuring probe. The bearing housing is provided with a vibration measuring structure for mounting a vibration sensor; the vibration measuring structure consists of vibration measuring holes 20 on the upper bearing housing 12 and the lower bearing housing 11. The vibration measuring hole 20 on the lower bearing housing 11 is used to measure the horizontal vibration of the sliding bearing; the vibration measuring hole 20 on the upper bearing housing 12 is used to measure the vertical vibration of the sliding bearing. The upper bearing housing 12 is provided with an exhaust hole 14, and an exhaust device 15, such as an automatic exhaust valve, is installed at the exhaust hole 14; the upper bearing housing 12 is provided with a lifting structure. The lifting structure consists of a lifting hole 21 on the upper bearing seat 12 and a lifting ring 22 installed on the lifting hole 21.

[0047] In one embodiment, the first bearing assembly 201 and the second bearing assembly 202 are sliding bearing bearings, and their inner working surfaces are covered with a friction-reducing layer.

[0048] The sliding bearing bush can be cylindrical, elliptical, or tilting bush, among other forms. To improve the bearing's wear resistance, anti-seize properties, compliance, and affinity for lubricating oil, thereby ensuring the formation of a stable and reliable oil film under high-speed, heavy-load, or frequent start-stop conditions, this embodiment features a friction-reducing layer specifically designed for the working surface. This friction-reducing layer is firmly attached to the bearing bush substrate, which is made of cast iron, cast steel, or copper alloy, through processes such as centrifugal casting, electroplating, spraying, or sintering. Typical friction-reducing layer materials include Babbitt alloys (such as tin-based or lead-based Babbitt alloys), copper-based alloys (such as aluminum bronze or lead bronze), or self-lubricating polymer composite materials.

[0049] According to an embodiment of the present invention, in another aspect, a dual-rotor speed-regulating motor is also provided, comprising two composite sliding bearings, a frame 51, a stator winding 61, an inner rotor 62, and an outer rotor 63; comprising two composite sliding bearings as a first sliding bearing 71 and a second sliding bearing 72; the stator winding 61 is fixed inside the frame 51; the outer rotor 63 is coaxially sleeved outside the inner rotor 62 and can rotate independently of the inner rotor 62; wherein, the first sliding bearing 71 and the second sliding bearing 72 are respectively installed at both axial ends of the frame 51; the first bearing assembly 201 of the first sliding bearing 71 and the first bearing assembly 201 of the second sliding bearing 72 jointly support the inner rotor 62; the second bearing assembly 202 of the first sliding bearing 71 and the second bearing assembly 202 of the second sliding bearing 72 jointly support the outer rotor 63.

[0050] In one embodiment, a sealing structure is further included, disposed between the inner rotor 62 and the outer rotor 63, for preventing bearing lubricating oil from entering the cavity between the inner and outer rotors 63.

[0051] In one embodiment, of the first sliding bearing 71 and the second sliding bearing 72, one is axially fixed relative to the base 51, while the other is allowed to float axially.

[0052] The motor includes a frame 51, a stator winding 61 fixed inside the frame 51, an inner rotor 62, an outer rotor 63, and two composite sliding bearings (serving as a first sliding bearing 71 and a second sliding bearing 72). Specifically, the frame 51 has a cylindrical or box-shaped structure. The left bearing housing 52 and the right bearing housing 53 are coaxially and fixedly connected to the left and right ends of the frame 51, respectively.

[0053] The inner rotor 62 is mainly composed of an inner rotor winding 621 and a shaft 622. The inner rotor winding 621 is fixedly sleeved on the shaft 622, forming the armature part of the motor.

[0054] The outer rotor 63 mainly consists of a first bearing housing 631, a support cylinder 632, a first permanent magnet 633, a second permanent magnet 634, and a second bearing housing 635. The support cylinder 632 is a rotating structure. The first permanent magnet 633 is fixed to the outer surface of the support cylinder 632, and the second permanent magnet 634 is fixed to the inner surface of the support cylinder 632. The first bearing housing 631 and the second bearing housing 635 are respectively fixedly connected to the left and right ends of the support cylinder 632.

[0055] The first sliding bearing 71 is fixedly mounted on the left bearing housing 52, and the second sliding bearing 72 is fixedly mounted on the right bearing housing 53. The first bearing bush assembly 201 of the first sliding bearing 71 and the first bearing bush assembly 201 of the second sliding bearing 72 are respectively sleeved on the left and right end journals of the shaft 622 of the inner rotor 62, together forming the rotational support for the inner rotor 62. The second bearing bush assembly 202 of the first sliding bearing 71 and the second bearing bush assembly 202 of the second sliding bearing 72 are respectively sleeved on the first bearing housing 631 and the second bearing housing 635 of the outer rotor 63, together forming the rotational support for the outer rotor 63. Thus, the inner rotor 62 and the outer rotor 63 are arranged coaxially from the inside to the outside, and can rotate independently without interfering with each other.

[0056] To further optimize the structure, prevent lubricating medium leakage, and isolate different chambers, the motor also includes a sealing structure, comprising a first bearing isolator 81 and a second bearing isolator 82. The inner ring of the first bearing isolator 81 is fitted and fixed to the shaft 622 at the left end, and its outer ring is coaxially mounted within the first bearing housing 631 of the outer rotor 63. The inner ring of the second bearing isolator 82 is fitted and fixed to the shaft 622 at the right end, and its outer ring is coaxially mounted within the second bearing housing 635 of the outer rotor 63. A non-contact sealing gap exists between the inner and outer rings of the two bearing isolators, which prevents lubricating oil in the sliding bearing cavity from leaking outwards and simultaneously prevents it from entering the cavity between the outer rotor 63 and the inner rotor 62.

[0057] In terms of axial positioning, the first sliding bearing 71 and the second sliding bearing 72 adopt a design with one end fixed and the other end floating. Specifically, the first sliding bearing 71 is completely positioned axially relative to the left bearing housing 52 to determine the axial reference of the entire rotor system and bear the axial force of the entire shaft system; while the second sliding bearing 72 is allowed to have a small axial relative displacement with the right bearing housing 53 to absorb the axial thermal expansion of the rotor caused by temperature rise during motor operation and prevent the bearing from seizing.

[0058] In addition, to achieve electrical connection between the inner rotor winding 621 and an external static power source, a slip ring 91 is installed at the right end of the shaft 622. A connecting plate 92 is coaxially fixed to the right bearing seat 53, and a brush holder 93 is fixed to the connecting plate 92. The carbon brushes on the brush holder 93 maintain sliding contact with the rotating slip ring 91 to transmit electrical signals. A protective cover 94 is fixed to the connecting plate 92, enclosing the slip ring 91 and the brush holder 93 within it, providing safety protection and dust prevention.

[0059] According to an embodiment of the present invention, in another aspect, a lubrication method for a dual-rotor speed-regulating motor is also provided, employing a composite sliding bearing, the method comprising: Provide one fuel supply line and then split it into a first branch line and a second branch line; The first branch lubricating oil is led to the first bearing assembly 201, and an oil film is formed between the first bearing assembly 201 and the inner rotor 62 shaft; The second branch lubricating oil is led to the second bearing assembly 202, and an oil film is formed between the second bearing assembly 202 and the bearing housing of the outer rotor 63. Collect the return oil from the first bearing assembly 201 and the second bearing assembly 202, and discharge it after they merge.

[0060] Specifically, the method includes the following steps: Step S1 (Oil Supply and Diversion): A single lubricating oil pump provides a stable flow of lubricating oil, which is delivered to the vicinity of the composite sliding bearing via a main oil supply pipeline. Subsequently, this oil supply is divided into a first branch and a second branch via a tee joint or a diverter integrated into the bearing housing. Optionally, an independent valve can be installed on each branch for initial adjustment or shut-off of the oil circuit.

[0061] Step S2 (Lubrication of the inner rotor 62 friction pair): The lubricating oil in the first branch is introduced through the first oil inlet 17 provided on the side wall of the lower bearing housing 11 of the composite sliding bearing. This first oil inlet 17 is directly connected to the oil inlet groove 41 on the lower bearing shell 32 of the first bearing assembly 201 installed inside the bearing housing. The lubricating oil fills the oil inlet groove 41 and seeps out through multiple oil inlet ports 42 distributed at the bottom of the groove. When the inner rotor 62 rotates, the first oil ring 43 installed on the first bearing assembly 201 rotates accordingly, carrying the lubricating oil from the oil inlet ports 42 and evenly coating it into the wedge-shaped gap between the inner bore surface of the first bearing assembly 201 and the journal of the inner rotor 62. Under the action of hydrodynamic pressure, the lubricating oil forms a stable pressure oil film in this gap, lifting the journal of the inner rotor 62, achieving non-contact support and lubrication.

[0062] Step S3 (Lubricating the outer rotor 63 friction pair): Simultaneously, lubricating oil from the second branch is introduced through the second oil inlet 17 on the lower bearing housing 11. This oil inlet 17 is connected to the oil inlet groove 41 on the lower bearing 32 of the second bearing assembly 202. Similarly, the lubricating oil, via its oil inlet 42 and transported by the rotation of the second oil ring 43, enters the gap between the inner surface of the second bearing assembly 202 and the journal (or bearing housing) of the outer rotor 63, forming an independent pressure oil film, thereby achieving non-contact support and lubrication of the outer rotor 63.

[0063] Step S4 (Oil Return Collection and Convergence): After the lubrication task is completed, the lubricating oil flowing from between the first bearing assembly 201 and the inner rotor 62 drips downwards due to gravity and collects in the first oil return chamber 33 located directly below it and machined into the lower bearing housing 11. Similarly, the lubricating oil flowing from between the second bearing assembly 202 and the outer rotor 63 collects in the second oil return chamber 34.

[0064] Step S5 (Unified Oil Return): The first oil return chamber 33 and the second oil return chamber 34 are not completely isolated inside the bearing housing; they are interconnected through a connecting channel. Therefore, the two independent oil return flows merge at this connecting channel, forming a single general oil return flow. Finally, this merged lubricating oil is discharged from the bearing housing through a common oil return outlet located on the bearing housing.

[0065] Step S6 (Oil Circulation): The lubricating oil discharged from the return oil outlet flows back to the external oil tank through the return oil pipe. In the oil tank, the lubricating oil is cooled and filtered to remove heat and impurities before being drawn back by the oil pump, thus completing a complete lubrication cycle.

[0066] This lubrication method, through a highly integrated bearing structure, requires only a single oil supply inlet and return outlet to achieve parallel lubrication and oil return collection for two independent friction pairs in a dual-rotor system. This greatly simplifies the external piping system, reduces leakage points, improves reliability, and is particularly suitable for dual-rotor motor applications with strict limitations on axial installation space.

[0067] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A composite sliding bearing, characterized in that, include: The bearing housing includes a lower bearing housing (11) and an upper bearing housing (12), wherein the lower bearing housing (11) is provided with a first bearing bush mounting part and a second bearing bush mounting part; The first bearing assembly (201) and the second bearing assembly (202) are respectively installed in the first bearing mounting part and the second shaft, and are used to support the inner rotor (62) and the outer rotor (63) that are coaxially arranged respectively. The lubrication circuit includes a first oil inlet and a second oil inlet provided in the lower bearing housing (11), and an oil guiding structure provided on the first bearing assembly (201) and the second bearing assembly (202); The first oil inlet passage is connected to the first bearing assembly (201), and the second oil inlet passage is connected to the second bearing assembly (202); The lower bearing housing (11) is provided with a first oil return chamber (33) and a second oil return chamber (34) that are respectively connected to the first bearing assembly (201) and the second bearing assembly (202). The first oil return chamber (33) and the second oil return chamber (34) are connected to each other and have a common oil return outlet.

2. The composite sliding bearing according to claim 1, characterized in that: The first bearing bush mounting part includes a first cavity formed by the small bearing bush lower seat (111) of the lower bearing seat (11) and the small bearing bush upper seat (121) of the upper bearing seat (12); The second bearing mounting part includes a second cavity formed by the large bearing lower seat (112) of the lower bearing seat (11) and the large bearing upper seat (122) of the upper bearing seat (12).

3. The composite sliding bearing according to claim 1 or 2, characterized in that: The oil guiding structure includes an oil inlet groove (41) disposed on the first bearing assembly (201) and the second bearing assembly (202), and an oil inlet port (42) communicating with the oil inlet groove (41). Oil rings (43) are respectively provided on the first bearing assembly (201) and the second bearing assembly (202).

4. The composite sliding bearing according to claim 1, characterized in that: The first bearing assembly (201) and the second bearing assembly (202) both include an upper bearing (31) and a lower bearing (32), and are fixed by a connector; The upper bearing seat (12) is provided with a positioning pin hole, and the upper bearing shell (31) is provided with a corresponding positioning pin hole. The circumferential positioning of the bearing shell assembly is achieved through the positioning pin.

5. The composite sliding bearing according to claim 1, characterized in that: The bearing housing is provided with a viewing structure for observing the oil level inside the bearing assembly; and The bearing housing is provided with a temperature measuring hole (13) for mounting a temperature measuring element; and The bearing housing is provided with a vibration measuring structure for mounting a vibration sensor; and The upper bearing housing (12) is provided with an exhaust port (14), and an exhaust device (15) is installed at the exhaust port (14); and The upper bearing housing (12) is equipped with a lifting structure.

6. The composite sliding bearing according to claim 1, characterized in that, The first bearing assembly (201) and the second bearing assembly (202) are sliding bearings, and their inner working surfaces are covered with a friction-reducing layer.

7. A dual-rotor speed-regulating motor, characterized in that, include: The composite sliding bearing as described in any one of claims 1 to 6 serves as the first sliding bearing (71) and the second sliding bearing (72). Base (51); The stator winding (61) is fixed inside the frame (51); The inner rotor (62) is rotatably disposed within the base (51); The outer rotor (63) is coaxially sleeved outside the inner rotor (62) and can rotate independently of the inner rotor (62); The first sliding bearing (71) and the second sliding bearing (72) are respectively installed at both ends of the axial direction of the base (51); the first bearing assembly (201) of the first sliding bearing (71) and the first bearing assembly (201) of the second sliding bearing (72) together support the inner rotor (62). The second bearing assembly (202) of the first sliding bearing (71) and the second bearing assembly (202) of the second sliding bearing (72) together support the outer rotor (63).

8. The dual-rotor speed-regulating motor according to claim 7, characterized in that, It also includes a sealing structure disposed between the inner rotor (62) and the outer rotor (63) to prevent bearing lubricating oil from entering the cavity between the inner and outer rotors (63).

9. The dual-rotor speed-regulating motor according to claim 7, characterized in that, Of the first sliding bearing (71) and the second sliding bearing (72), one is axially fixed relative to the base (51), while the other is allowed to float axially.

10. A lubrication method for a dual-rotor speed-regulating motor, characterized in that, The method, employing a composite sliding bearing as described in any one of claims 1 to 6, comprises: Provide one fuel supply line and then split it into a first branch line and a second branch line; The first branch lubricating oil is led to the first bearing assembly (201) and an oil film is formed between the first bearing assembly (201) and the inner rotor (62) shaft; The second branch lubricating oil is led to the second bearing assembly (202) and an oil film is formed between the second bearing assembly (202) and the outer rotor (63) bearing housing; Collect the return oil from the first bearing assembly (201) and the second bearing assembly (202), and discharge it after they are combined.

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