A drive structure for a roller vertical mill

Abstract

This utility model relates to a drive structure for a roller vertical mill, belonging to the field of roller vertical mill equipment. The technical solution is as follows: a drive structure for a roller vertical mill includes a drive motor, which comprises a motor housing and a motor shaft. The two ends of the motor shaft are the drive end and the non-drive end, respectively. A first roller bearing and a deep groove ball bearing are provided on the portion of the motor shaft near the drive end, with the deep groove ball bearing located on the side of the first roller bearing closest to the drive end. A second roller bearing is provided on the portion of the motor shaft near the non-drive end. This solution employs a combination of roller bearings and deep groove ball bearings. The deep groove ball bearing can bear both radial and axial loads. Located on the drive end side, it helps to counteract the axial vibration and impact transmitted by the mill through the coupling, complementing the first roller bearing, effectively reducing bearing temperature and vibration, and improving the motor's operational stability and lifespan.

Description

Technical Field

[0001] This utility model relates to the field of roller vertical mill equipment, and in particular to a roller vertical mill drive structure. Background Technology

[0002] A vertical roller mill is a large-scale grinding equipment used for fine powder processing, widely applied to the fine grinding of materials such as slag and cement. Its core working principle is to process lumpy or granular materials into fine powder through the squeezing and grinding action between the rollers and the grinding disc. In this equipment, the main motor is the core power source of the drive system, providing continuous power for the mill's grinding operation. The drive shaft of the main motor is supported at both ends by bearings. One end, connected to the coupling, is the shaft extension end (drive end), responsible for transmitting torque and power to the reducer, thereby driving the mill's grinding disc and rollers. The other end, the non-shaft extension end (slip ring side, non-drive end), mainly serves to support the drive shaft.

[0003] The existing main motor bearings employ a combination structure with one self-aligning roller bearing on each of the drive and non-drive ends. The outer ring raceway of the self-aligning roller bearings is spherical, providing excellent self-aligning performance. This compensates for coaxiality errors between the drive shaft and the bearing housing, reducing impacts caused by installation misalignment or vibration. For the drive end, vibrations from the vertical roller mill may be transmitted to this end through the coupling. The self-aligning function of the self-aligning roller bearings effectively buffers vibration loads and reduces impact on the shaft extension end, thus it is generally considered a reasonable bearing configuration.

[0004] However, the non-drive end, as a "movable end" that needs to adapt to thermal expansion and contraction during equipment operation, requires a certain axial movement capability to release stress caused by temperature changes and loads, and to avoid excessive force between the bearing and the drive shaft and bearing housing. Self-aligning roller bearings cannot withstand pure axial loads; their axial displacement is strictly limited to their own axial clearance range, making it difficult to meet the axial movement requirements of the non-drive end. Therefore, bearing damage and downtime frequently occur during actual equipment use. Summary of the Invention

[0005] This invention addresses the problem that current roller mill main motors, which use self-aligning roller bearings at both ends, cannot meet the requirements for axial movement, leading to easy motor damage. It provides a new drive structure for roller mills.

[0006] To solve the above problems, the technical solution adopted by this utility model is a drive structure for a roller vertical mill, including a drive motor. The drive motor includes a motor housing and a motor shaft. The two ends of the motor shaft are a drive end and a non-drive end, respectively. A first shoulder is provided on the part of the motor shaft near the drive end. A first roller bearing and a deep groove ball bearing are provided at the first shoulder. The deep groove ball bearing is located on the side of the first roller bearing near the drive end. A second shoulder is provided on the part of the motor shaft near the non-drive end. A second roller bearing is provided at the second shoulder. The outer rings of the first roller bearing, the deep groove ball bearing, and the second roller bearing are fixedly connected to the motor housing. This design changes the traditional bearing arrangement of the main motor of a roller mill. The roller bearings mainly bear radial loads, while the deep groove ball bearings have radial clearance. When the inner and outer rings of the deep groove ball bearings undergo radial displacement, they can function as angular contact ball bearings, thus possessing both radial and axial load-bearing capabilities. Positioned on one side of the drive end, they can help offset the axial vibration and impact transmitted by the mill through the coupling, complementing the first roller bearing, effectively reducing bearing temperature and vibration, and improving the stability and lifespan of the motor.

[0007] As a preferred implementation of the drive structure for a vertical roller mill, the motor housing includes a rotor cavity, which is cylindrical. A first roller bearing and a deep groove ball bearing are mounted on the first end face of the rotor cavity, and the drive end of the motor shaft extends beyond the first end face of the rotor cavity. A second roller bearing is mounted on the second end face of the rotor cavity. This improves the coaxiality accuracy of the bearing installation, reduces the additional torque caused by reference deviation, and the symmetrical distribution of the bearings makes load transmission smoother, reduces the risk of localized wear, and further reduces vibration and heat generation.

[0008] As a preferred implementation of the drive structure for a roller mill, the motor housing further includes a thrust chamber located outside the second end face of the rotor cavity. The non-driving end of the motor shaft passes through the second end face of the rotor cavity and is located within the thrust chamber. A thrust mechanism is provided within the thrust chamber and connected to the non-driving end. The thrust mechanism presses the motor shaft axially towards the drive end. The thrust mechanism provides a pre-clamping force in the axial direction towards the drive end, reducing axial movement during operation and ensuring relative axial stability of the motor shaft.

[0009] In a preferred embodiment of the drive structure for a roller mill, the thrust mechanism includes a sliding sleeve slidably mounted in the thrust chamber. The sliding sleeve has two through-holes, and a spacer ring is provided within the hole of the sliding sleeve. An angular contact ball bearing is located on the side of the spacer ring facing the drive end, with its point of action located on its own side facing the drive end. The non-drive end is connected to the inner ring of the angular contact ball bearing. A spring is provided on the side of the spacer ring facing away from the drive end. The angular contact ball bearing, with its point of action facing the drive end, can withstand the reverse axial force transmitted from the drive end and transmit the force to the spring through the spacer ring. The spring absorbs axial impact through elastic deformation and simultaneously generates a continuous clamping force to balance axial displacement.

[0010] As a preferred implementation of the drive structure for a roller mill, the outer circumferential surface of the sliding sleeve slides in contact with the inner circumferential surface of the thrust cavity. The contact fit between the sliding sleeve and the inner surface of the thrust cavity reduces radial runout, ensures a single and stable motion pattern at the non-drive end, and guarantees a buffering effect.

[0011] As a preferred implementation of the drive structure for a roller mill, a threaded hole is provided at the center of the second end face of the thrust chamber. A threaded rod is installed in the threaded hole. A pressure plate is provided at one end of the threaded rod inside the thrust chamber, and the pressure plate abuts against the end of the spring away from the spacer ring. A rotation operation structure is provided at the end of the threaded rod outside the thrust chamber. The thrust can be flexibly adjusted according to the motor operating conditions to adapt to the axial force requirements under different operating conditions. The adjustable preload avoids abnormal bearing stress caused by excessive or insufficient spring force, improving the versatility and adaptability of the structure.

[0012] As a preferred implementation of the drive structure for a roller mill, the rotating operating structure is a bolt head. The bolt head can be easily rotated using tools such as wrenches, driving the threaded rod to rotate and adjusting the preload. Using common tools reduces the difficulty of adjusting the thrust mechanism and facilitates quick adjustments by on-site maintenance personnel.

[0013] As a preferred implementation of the drive structure for a roller mill, bearing chambers are respectively provided on both end faces of the motor housing, and the first roller bearing, the deep groove ball bearing, and the second roller bearing are all located in the bearing chambers. The impact of the coupling on the motor drive end bearings is reduced by minimizing mill vibration, and the bearing assembly at the drive end further buffers the load, preventing bearing damage due to vibration overload and improving the overall stability of the drive system.

[0014] As a preferred implementation of the drive structure for a roller mill, the drive end is equipped with a metal diaphragm coupling, which is connected to an external load. The coupling reduces the impact of mill vibration on the motor drive end bearings, and the bearing assembly at the drive end further buffers the load, preventing bearing damage due to vibration overload and improving the overall stability of the drive system.

[0015] As a preferred implementation of the drive structure for a roller mill, the first side of the metal diaphragm coupling is connected to the drive end, and the second side of the metal diaphragm coupling is equipped with a reduction gearbox. This achieves efficient power transmission, meets the mill's torque requirements, reduces the mutual vibration interference between the motor and the reduction gearbox, protects the bearings at both ends, and improves the operational reliability of the entire drive chain.

[0016] As can be seen from the above technical solutions, the advantages of this utility model are as follows: This solution adopts a combination of roller bearings and deep groove ball bearings, which solves the problem of axial movement restriction in traditional self-aligning roller bearings. Roller bearings mainly bear radial loads and allow axial movement to adapt to thermal expansion and contraction, while deep groove ball bearings have both radial and axial load-bearing capabilities, which can help offset the axial vibration and impact transmitted by the mill, complementing the roller bearings and effectively reducing bearing temperature and vibration, significantly improving the stability and service life of the motor operation; The symmetrical installation design of the cylindrical rotor cavity and the bearings at both ends improves the coaxiality accuracy of the bearing installation, reduces the additional torque caused by the reference deviation, makes the load transmission smoother, reduces the risk of local wear, and further reduces vibration and heat generation; The thrust mechanism set at the non-drive end provides pre-tightening force in the direction of the drive end, reducing the amount of axial movement during operation and ensuring the relative stability of the motor shaft in the axial direction. Among them, the angular contact ball bearing can withstand the reverse axial force, and the spring passes through... Elastic deformation absorbs axial impact and generates continuous clamping force to balance axial displacement; the sliding contact between the sliding sleeve and the thrust chamber reduces radial runout, ensuring the single and stable motion of the non-drive end and ensuring a buffering effect; the design of the threaded rod and bolt head in the thrust mechanism allows for flexible adjustment of the thrust according to the motor's operating conditions, adapting to the axial force requirements under different conditions, avoiding bearing stress problems caused by abnormal spring force, improving the versatility and adaptability of the structure, and can be easily operated with common tools, reducing adjustment difficulty and facilitating quick adjustments by on-site maintenance personnel; the bearing chambers at both ends of the motor housing provide stable protection for the bearings; the cooperation between the metal diaphragm coupling and the gearbox not only reduces the impact of mill vibration on the motor drive end bearings, further buffering the load and preventing bearing damage due to vibration overload, but also achieves efficient power transmission, meeting the mill's torque requirements, reducing the mutual influence of vibration between the motor and the gearbox, protecting the bearings at both ends, and comprehensively improving the operational reliability of the entire drive chain. Attached Figure Description

[0017] To more clearly illustrate the technical solution of this utility model, the drawings used in the description will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a structural schematic diagram of a specific embodiment of the present utility model.

[0019] Explanation of main figure symbols 1. Drive motor, 2. First shoulder, 3. Second shoulder, 4. First roller bearing, 5. Deep groove ball bearing, 6. Second roller bearing, 7. Sliding sleeve, 8. Spacer ring, 9. Angular contact ball bearing, 10. Spring, 11. Motor housing, 11-1. Rotor cavity, 11-2. Thrust cavity, 12. Motor shaft, 12-1. Drive end, 12-2. Non-drive end, 13. Threaded rod, 14. Pressure plate, 15. Metal diaphragm coupling, 16. Gearbox. Detailed Implementation

[0020] To make the objectives, features, and advantages of this utility model more apparent and understandable, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings of the specific embodiments. Obviously, the embodiments described below are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this patent, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this patent.

[0021] like Figure 1As shown, a drive structure for a roller mill includes a drive motor 1. The drive motor 1 includes a motor housing 11 and a motor shaft 12. The two ends of the motor shaft 12 are a drive end 12-1 and a non-drive end 12-2, respectively. A first shoulder 2 is provided on the portion of the motor shaft 12 near the drive end 12-1. A first roller bearing 4 and a deep groove ball bearing 5 are provided at the first shoulder 2. The deep groove ball bearing 5 is located on the side of the first roller bearing 4 near the drive end 12-1. A second shoulder 3 is provided on the portion of the motor shaft 12 near the non-drive end 12-2. A second roller bearing 6 is provided at the second shoulder 3. The outer rings of the first roller bearing 4, the deep groove ball bearing 5, and the second roller bearing 6 are fixedly connected to the motor housing 11. Correspondingly, the motor housing 11 includes a rotor cavity 11-1, which is cylindrical. Bearing chambers 11-3 are respectively provided on the two end faces of the motor housing 11. The first roller bearing 4 and the deep groove ball bearing 5 are installed in the bearing chamber on the first end face of the rotor cavity 11-1. The drive end 12-1 of the motor shaft 12 extends out of the first end face of the rotor cavity 11-1. The second roller bearing 6 is installed in the bearing chamber on the second end face of the rotor cavity 11-1. Therefore, the first and second roller bearings are preferably single-row roller bearings. The first roller bearing mainly bears radial loads, and its structure allows for a certain amount of axial movement of the motor shaft. The deep groove ball bearing has both radial and axial load-bearing capacity and, located on the drive end side, can help offset the axial vibration and impact transmitted by the mill through the coupling, complementing the first roller bearing. The second roller bearing only bears radial loads, and due to the structural characteristics of roller bearings, it provides axial movement space for the non-drive end, accommodating the axial displacement of the motor shaft caused by thermal expansion and contraction. The outer rings of all three bearings are fixed to the motor housing, while the inner rings rotate with the motor shaft. By combining bearing types, the radial and axial loads are balanced and stress is released, solving the problem of the original self-aligning roller bearings at both ends restricting axial movement. The roller bearings at the non-drive end can freely adapt to axial displacement, avoiding stress concentration. The deep groove ball bearings at the drive end enhance the axial load-bearing capacity, compensating for the weak axial load of roller bearings, effectively reducing bearing temperature and vibration, and improving the stability and lifespan of the motor operation.

[0022] The cylindrical rotor cavity provides a stable mounting reference for the motor shaft and bearings, ensuring the coaxiality of the bearing outer ring with the motor housing. The drive end bearing is installed on the first end face of the rotor cavity, and the non-drive end bearing is installed on the second end face, so that the bearings are symmetrically distributed along the motor shaft axis. The bearing housing provides precise installation positioning and radial support for the bearings, ensuring the rigid connection between the bearing outer ring and the motor housing, while isolating external dust and impurities and protecting the internal raceways and rollers of the bearing.

[0023] Furthermore, the drive structure also includes a thrust mechanism. The motor housing 11 further includes a thrust cavity 11-2, in which the thrust mechanism is located. The thrust cavity 11-2 is located outside the second end face of the rotor cavity 11-1. The non-driving end 12-2 of the motor shaft 12 passes through the second end face of the rotor cavity 11-1 and is located in the thrust cavity 11-2. The thrust mechanism is connected to the non-driving end 12-2 and presses the motor shaft 12 towards the driving end 12-1. The thrust mechanism includes a sliding sleeve 7, which is slidably installed in the thrust cavity 11-2. The outer circumferential surface of the sliding sleeve 7 is in sliding contact with the inner circumferential surface of the thrust cavity 11-2. The two ends of the sliding sleeve 7 are open. A spacer 8 is provided in the hole of the sliding sleeve 7. An angular contact ball bearing 9 is provided on the side of the spacer 8 facing the driving end 12-1. The point of action of the angular contact ball bearing 9 is ( Figure 1 Point A in the diagram represents the point of action of the angular contact ball bearing, which is the intersection of the normal direction of the contact point between the rolling elements inside the bearing and the inner and outer raceways, and the bearing axis. This point is the point of force transmission when the bearing is under load. Point A is located on the side of the angular contact ball bearing facing the drive end 12-1. The non-drive end 12-2 is connected to the inner ring of the angular contact ball bearing 9. A spring 10 is provided on the side of the spacer 8 facing away from the drive end 12-1. The sliding sleeve can slide in the thrust chamber, providing buffer space for the axial displacement of the motor shaft. The point of action of the angular contact ball bearing faces the drive end, allowing it to withstand the reverse axial force from the non-drive end, and transmits the force to the spring through the spacer. The spring absorbs axial impact through elastic deformation, while simultaneously generating a continuous clamping force to balance the axial displacement, preventing the inner ring of the bearing from separating from the shaft shoulder or excessive clearance due to reverse axial movement of the motor shaft, thus avoiding increased vibration. The clamping force maintains stable bearing clearance, reduces impact loads, and extends bearing life.

[0024] A threaded hole is also provided at the center of the second end face of the thrust chamber 11-2. A threaded rod 13 is installed in the threaded hole. One end of the threaded rod 13 inside the thrust chamber 11-2 is provided with a pressure plate 14. The pressure plate 14 abuts against the end of the spring 10 away from the spacer ring 8. The other end of the threaded rod 13 outside the thrust chamber 11-2 is provided with a rotation operating structure. In this embodiment, the rotation operating structure is a bolt head 13-1. The bolt head can be easily rotated with a wrench or other tools to drive the threaded rod to rotate, thereby adjusting the preload. The operation is simple and conforms to conventional mechanical maintenance habits. Thus, by rotating the external operating structure to adjust the screw depth of the threaded rod, the pressure plate moves with the threaded rod to change the compression of the spring, thereby adjusting the spring preload and achieving precise control of the motor shaft clamping force.

[0025] The drive end 12-1 is equipped with a metal diaphragm coupling 15, which is connected to an external load. The first side of the metal diaphragm coupling 15 is connected to the drive end 12-1, and the second side of the metal diaphragm coupling 15 is equipped with a reduction gearbox 16. The metal diaphragm coupling, through the elastic deformation of the metal diaphragm and the internal component clearances of the reduction gearbox, compensates for coaxiality errors and slight axial and radial displacements between the drive end and the external load, reducing vibration transmission. The metal diaphragm coupling connects the motor drive end and the reduction gearbox, converting the high speed and low torque of the motor into low speed and high torque output from the reduction gearbox, adapting to the grinding conditions of the mill. The elastic deformation of the coupling also isolates vibration transmission between the motor and the reduction gearbox.

[0026] As can be seen from the above embodiments, the beneficial effects of this utility model are as follows: This solution uses a combination of roller bearings and deep groove ball bearings. The roller bearings bear radial loads and allow axial movement, while the deep groove ball bearings have both radial and axial load-bearing capabilities, assisting in offsetting axial vibration and impact. They complement the roller bearings, reducing bearing temperature and vibration, and improving motor operating stability and lifespan. The cylindrical rotor cavity and the bearings at both ends are symmetrically installed, improving the bearing installation coaxiality accuracy, reducing additional torque, ensuring smooth load transmission, reducing the risk of local wear, and reducing vibration and heat generation. The non-drive end thrust mechanism provides pre-clamping force to the drive end, reducing axial movement and ensuring axial stability of the motor shaft. The angular contact ball bearings in the thrust mechanism... Under reverse axial force, the spring absorbs axial impact and generates continuous clamping force to balance axial displacement; the sliding sleeve slides in contact with the thrust chamber, reducing radial runout, ensuring stable movement at the non-drive end, and ensuring a buffering effect; the threaded rod and bolt head design allows for flexible adjustment of thrust to adapt to different axial force requirements under different working conditions, avoiding abnormal bearing stress, improving versatility and adaptability, and facilitating operation and on-site adjustment; the bearing chambers at both ends of the motor housing protect the bearings, and the metal diaphragm coupling cooperates with the gearbox to reduce the impact of vibration on the drive end bearings, buffer the load, avoid bearing damage, achieve efficient power transmission, meet the mill torque requirements, reduce the vibration impact between the motor and the gearbox, protect the bearings at both ends, and improve the reliability of the entire drive chain.

[0027] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A drive structure for a roller mill, comprising a drive motor (1), the drive motor (1) comprising a motor housing (11) and a motor shaft (12), the two ends of the motor shaft (12) being a drive end (12-1) and a non-drive end (12-2), characterized in that, The motor shaft (12) near the drive end (12-1) is provided with a first shoulder (2), and a first roller bearing (4) and a deep groove ball bearing (5) are provided at the first shoulder (2). The deep groove ball bearing (5) is located on the side of the first roller bearing (4) near the drive end (12-1). The motor shaft (12) near the non-drive end (12-2) is provided with a second shoulder (3), and a second roller bearing (6) is provided at the second shoulder (3). The outer rings of the first roller bearing (4), the deep groove ball bearing (5) and the second roller bearing (6) are fixedly connected to the motor housing (11).

2. The roller mill drive structure according to claim 1, characterized in that, The motor housing (11) includes a rotor cavity (11-1), which is cylindrical. The first roller bearing (4) and the deep groove ball bearing (5) are mounted on the first end face of the rotor cavity (11-1). The drive end (12-1) of the motor shaft (12) extends out of the first end face of the rotor cavity (11-1). The second roller bearing (6) is mounted on the second end face of the rotor cavity (11-1).

3. The roller mill drive structure according to claim 2, characterized in that, The motor housing (11) also includes a thrust cavity (11-2), which is located outside the second end face of the rotor cavity (11-1). The non-driving end (12-2) of the motor shaft (12) passes through the second end face of the rotor cavity (11-1). The non-driving end (12-2) is located in the thrust cavity (11-2). A thrust mechanism is provided in the thrust cavity (11-2). The thrust mechanism is connected to the non-driving end (12-2). The thrust mechanism pushes the motor shaft (12) towards the driving end (12-1).

4. The roller mill drive structure according to claim 3, characterized in that, The thrust mechanism includes a sliding sleeve (7), which is slidably installed in the thrust cavity (11-2). The two ends of the sliding sleeve (7) are open. A spacer (8) is provided in the hole of the sliding sleeve (7). An angular contact ball bearing (9) is provided on the side of the spacer (8) facing the drive end (12-1). The point of action of the angular contact ball bearing (9) is located on the side of itself facing the drive end (12-1). The non-drive end (12-2) is connected to the inner ring of the angular contact ball bearing (9). A spring (10) is provided on the side of the spacer (8) facing away from the drive end (12-1).

5. The roller mill drive structure according to claim 4, characterized in that, The outer peripheral surface of the sliding sleeve (7) slides in contact with the inner peripheral surface of the thrust cavity (11-2).

6. The roller mill drive structure according to claim 4, characterized in that, A threaded hole is provided at the center of the second end face of the thrust cavity (11-2), and a threaded rod (13) is installed in the threaded hole. One end of the threaded rod (13) located inside the thrust cavity (11-2) is provided with a pressure plate (14). The pressure plate (14) abuts against the end of the spring (10) away from the spacer ring (8). The end of the threaded rod (13) located outside the thrust cavity (11-2) is provided with a rotation operation structure.

7. The roller mill drive structure according to claim 6, characterized in that, The rotating operating structure is a bolt head (13-1).

8. The roller mill drive structure according to any one of claims 1-7, characterized in that, The motor housing (11) has bearing chambers (11-3) on both ends, and the first roller bearing (4), the deep groove ball bearing (5) and the second roller bearing (6) are all located in the bearing chambers (11-3).

9. The roller mill drive structure according to any one of claims 1-7, characterized in that, The drive end (12-1) is provided with a metal diaphragm coupling (15), which is connected to an external load.

10. The roller mill drive structure according to claim 9, characterized in that, The first side of the metal diaphragm coupling (15) is connected to the drive end (12-1), and the second side of the metal diaphragm coupling (15) is provided with a reduction gearbox (16).

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