Integrated dismounting device for roller bearing system

By designing an integrated disassembly device of the roller bearing system including a roller placing frame and a pulling drive frame, the problems of long disassembly, large errors and insecurity in the prior art are solved, and an efficient and safe bearing disassembly process is achieved. .

CN222472428UInactive Publication Date: 2025-02-14SHANG HAI WU GANG SHE BEI GONG CHENG YOU XIAN GONG SI +1
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Patent Information

Application Number
CN202421083674.8
Authority / Receiving Office
CN · China
Patent Type
Utility models(China)
Current Assignee / Owner
Filing Date
2024-05-17
Publication Date
2025-02-14
Estimated Expiration
Not applicable · inactive patent

AI Technical Summary

Technical Problem

In the prior art, when disassembling bearing seats and other components on roller ducts, the error is large, time-consuming, multiple people need to cooperate, and there are unsafe factors, resulting in mechanical damage and damage to the roller surface.

Method used

An integrated disassembly device for roller bearing system is designed, including a roller placing frame and a pulling drive frame. The vertical lifting mechanism, jaw mechanism and transverse ejection mechanism are used to realize automatic disassembly of bearing seats and other components to ensure that The jaw and ejection mechanism are coaxial with the roller to avoid skew and damage.

Benefits of technology

Through the automated disassembly process, the manpower demand and working time are significantly reduced, the disassembly efficiency is improved, the damage and mechanical damage to the roller surface are avoided, and unsafe factors are reduced.

✦ Generated by Eureka AI based on patent content.

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Abstract

The utility model relates to the technical field of equipment maintenance, in particular to an integrated dismounting device for a roller way bearing system. The dismounting device comprises a carrier roller placing frame and a drawing driving frame, wherein the carrier roller placing frame and the drawing driving frame are both arranged on the horizontal ground of a workshop; a plurality of carrier roller placing areas capable of horizontally and transversely placing carrier rollers are arranged at the top of the carrier roller placing frame in parallel at intervals; the drawing driving frame is provided with a frame body, a vertical lifting mechanism, a clamping jaw mechanism and a transverse ejection mechanism, the vertical lifting mechanism is arranged on the frame body, the clamping jaw mechanism and the transverse ejection mechanism are both arranged on a lifting block of the vertical lifting mechanism, and the transverse ejection mechanism is located in the interval space among a plurality of clamping jaws on the clamping jaw mechanism. According to the dismounting device, the to-be-dismounted part can be prevented from inclining in the dismounting process, so that the dismounting efficiency is improved, damage to the surface of the carrier roller is avoided, manpower is reduced, and the operation time is shortened.
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Description

Technical Field

[0001] The utility model relates to the technical field of equipment maintenance, in particular to an integrated disassembly device for a roller bearing system. Background Art

[0002] In rolling production, medium plates, thick plates and other steel plates rolled by the equipment need to be transported by rollers. With the long-term transportation of steel plates, parts such as the bearing seats on the rollers of the rollers will wear out. Therefore, it is necessary to frequently replace the bearing seats, bearings and couplings on the rollers.

[0003] At present, the construction process for dismantling the bearing seat and other components on the roller is to first make a simple frame, and place the bearing seat and other components in the simple frame, one end of the hydraulic jack is abutted against the inner wall of the simple frame, and the other end is abutted against the circumferential outer end of the roller, so that the simple frame, together with the bearing seat, bearing or coupling on the roller, is driven to move relative to the roller by lifting the hydraulic jack, thereby realizing the dismantling of the bearing seat and other components on the roller.

[0004] However, since the above-mentioned process is relatively simple and has large errors, the hydraulic jack is often not coaxial with the roller of the roller. During the disassembly process, the parts to be disassembled will be stuck on the roller due to skewness and cannot move. Therefore, it is necessary to use a sledgehammer to continuously hit the parts to be disassembled so that the parts to be disassembled can be successfully ejected through the hydraulic jack. In addition, when using the above-mentioned process to disassemble the parts, it is necessary to heat the bearings first and then use the hydraulic jack to eject them, which is time-consuming; in the process of removing the bearing seat, a crane is also required to cooperate with the operation. For this reason, it takes nearly a day to completely remove the bearing seat, bearings and couplings on a roller of the roller using the above-mentioned process, and 4-5 people are required to cooperate with the operation. The use of a crane to cooperate with the operation during the disassembly process will also produce unsafe factors, which is prone to mechanical injuries, and the knocking of the sledgehammer will also cause relatively large damage to the surface of the roller. Utility Model Content

[0005] In order to solve the above technical problems, the utility model provides an integrated disassembly device for a roller bearing system which can reduce unsafe factors, reduce manpower and shorten operation time.

[0006] The utility model adopts the following technical solutions:

[0007] The utility model provides an integrated disassembly device for a roller bearing system, comprising a roller placing frame and a pulling drive frame, wherein the roller placing frame and the pulling drive frame are both arranged on the horizontal ground of a workshop; a plurality of supporting areas capable of horizontally and laterally placing rollers are arranged in parallel and at intervals on the top of the roller placing frame; a frame body, a vertical lifting mechanism, a clamping claw mechanism and a horizontal ejecting mechanism are arranged on the pulling drive frame, the vertical lifting mechanism is arranged on the frame body, the clamping claw mechanism and the horizontal ejecting claw mechanism are both arranged on the lifting block of the vertical lifting mechanism, and the horizontal ejecting claw mechanism is located in the interval space between a plurality of clamping claws on the clamping claw mechanism.

[0008] Preferably, two lifting supporting platforms are arranged at intervals in each supporting area on the top of the roller placement frame, the tops of the two lifting supporting platforms are provided with concave arc grooves for supporting the rollers, and the two lifting supporting platforms are lifted and lowered synchronously.

[0009] Preferably, a universal wheel set is installed at the bottom of the roller placement frame, and each universal wheel in the universal wheel set is equipped with a stop locking assembly.

[0010] Preferably, the vertical lifting mechanism includes a lifting rail, a lifting block and a lifting drive assembly. The two lifting rails are maintained parallel and erected at intervals at the edge of the top of the frame. The lifting block can be freely slidably installed on the two lifting rails. The lifting drive assembly is arranged on the frame and located above the lifting rails, and a connecting rope is wrapped around the driving end of the lifting drive assembly. The end of the connecting rope is connected and fixed to the top center of the lifting block.

[0011] Preferably, the lifting drive assembly includes a driving motor and a fixed pulley group, the driving motor is arranged on the frame, the fixed pulley group is arranged directly above the lifting track, the connecting rope is wrapped around the driving end of the driving motor, and the end of the connecting rope passes around the fixed pulley group and is connected and fixed to the top center of the lifting block.

[0012] Preferably, the clamping mechanism comprises a clamping jaw, a telescopic driving assembly and a connecting rod assembly, the two clamping jaws are symmetrically hinged on the lateral side of the lifting block away from the frame body, the telescopic driving assembly is arranged on the lifting block and is located between the two clamping jaws, one end of the connecting rod assembly is connected to the driving end of the telescopic driving assembly, and the other end is connected to the two clamping jaws at the same time.

[0013] Preferably, the lateral ejection mechanism includes an ejection drive assembly and an ejection shaft. The ejection drive assembly is arranged in the lifting block, and the ejection end of the ejection drive assembly passes through the lifting block and is arranged away from the lateral side of the frame. The ejection shaft is axially fixed on the ejection end of the ejection drive assembly.

[0014] Preferably, a push-pull handle is installed on the top of the frame, a pair of fixed wheels is installed on the front side of the bottom of the frame, a pair of universal wheels is installed on the rear side of the bottom, and the pair of universal wheels are equipped with a stop locking assembly.

[0015] Compared with the prior art, the beneficial effects of the utility model are:

[0016] When the roller bearing system integrated disassembly device of the utility model is in use, the rollers on the roller are first transferred to the supporting area of ​​the roller placement frame by the crane, and then the drawing drive frame is moved to the position of the roller by the crane. After that, the height of the lifting block can be adjusted by the vertical lifting mechanism, so that the clamping claw mechanism and the horizontal ejection mechanism are coaxial with the roller, and then the clamping claw of the clamping claw mechanism is controlled to open and hook on the part to be disassembled, and finally the roller is lifted horizontally by the horizontal ejection mechanism, so that the part to be disassembled can be moved relative to the roller and finally separated from the roller.

[0017] Since the entire disassembly process is basically carried out automatically by the integrated disassembly device of the roller bearing system, the operator only needs to control the movement of the device, and the adjustment of the height of the lifting block by the vertical lifting mechanism can make the clamping mechanism and the lateral ejection mechanism coaxial with the roller, avoiding the skew of the parts to be disassembled during the disassembly process, thereby improving the disassembly efficiency, avoiding damage to the roller surface, and helping to reduce manpower and shorten the operation time. At the same time, the crane is only involved before the disassembly begins, and after the disassembly work officially begins, the crane is no longer needed, thereby reducing unsafe factors and avoiding mechanical injuries. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the use status of the integrated disassembly device of the roller bearing system in the embodiment of the utility model.

[0019] Figure 2 It is a structural schematic diagram of a roller placement frame on an integrated disassembly device of a roller bearing system in an embodiment of the utility model.

[0020] Figure 3 It is a schematic diagram of the structure of a pulling drive frame on an integrated disassembly device of a roller bearing system in an embodiment of the utility model.

[0021] The reference numerals are described as follows:

[0022] 1. Roller rack 210, hydraulic station

[0023] 2. Pull-out drive frame 211, push-pull handle

[0024] 201, frame 212, directional wheel

[0025] 202, lifting block 213, universal wheel

[0026] 203, clamp 3, roller

[0027] 204, lifting track 301, bearing seat

[0028] 205, connecting rope 4, transfer fixture

[0029] 207, fixed pulley block 5, lifting support platform

[0030] 208, ejector drive assembly 501, concave arc groove

[0031] 209. Ejector shaft DETAILED DESCRIPTION

[0032] The following is a further detailed description of the specific implementations of the present invention in conjunction with the accompanying drawings. These implementations are only used to illustrate the present invention, but not to limit the present invention.

[0033] In the description of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0034] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] In addition, in the description of the present invention, unless otherwise specified, “plurality” means two or more.

[0036] See also Figures 1 to 3The present embodiment provides an integrated disassembly device for a roller bearing system, comprising a roller placing rack 1 and a pulling drive rack 2, both of which are arranged on the horizontal ground of a workshop; a plurality of supporting areas capable of horizontally placing rollers 3 are arranged in parallel and at intervals on the top of the roller placing rack 1; a frame body 201, a vertical lifting mechanism, a clamping mechanism and a horizontal ejection mechanism are provided on the pulling drive rack 2, the vertical lifting mechanism is arranged on the frame body 201, the clamping mechanism and the horizontal ejection mechanism are both arranged on the lifting block 202 of the vertical lifting mechanism, and the horizontal ejection mechanism is located in the interval space between the plurality of clamping jaws 203 on the clamping mechanism.

[0037] When the integrated disassembly device of the roller bearing system of this embodiment is in use, the roller 3 on the roller is first transferred to the supporting area of ​​the roller placement frame 1 by the crane, and then the drawing drive frame 2 is moved to the position of the roller 3 by the crane. After that, the height of the lifting block 202 can be adjusted by the vertical lifting mechanism, so that the clamping mechanism and the lateral ejection mechanism are coaxial with the roller 3, and then the clamping jaws 203 of the clamping mechanism are controlled to open and hook on the part to be disassembled, and finally the roller 3 is lifted horizontally by the lateral ejection mechanism, so that the part to be disassembled can be moved relative to the roller 3 and finally separated from the roller 3.

[0038] Since the entire disassembly process is basically carried out automatically by the integrated disassembly device of the roller bearing system, the operator only needs to control the movement of the device, and the adjustment of the height of the lifting block 202 by the vertical lifting mechanism can make the clamping mechanism and the lateral ejection mechanism coaxial with the roller 3, avoiding the skew of the parts to be disassembled during the disassembly process, thereby improving the disassembly efficiency, avoiding damage to the surface of the roller, and helping to reduce manpower and shorten the operation time. At the same time, the crane is only involved before the disassembly begins, and after the disassembly work officially begins, the crane is no longer needed, thereby reducing unsafe factors and avoiding mechanical injuries.

[0039] It should be noted that since the parts to be disassembled include the bearing seat, bearing and coupling on the roller 3, and the bearing and coupling can be directly hooked with the clamping claw 203 on the clamping claw mechanism, but the bearing seat 301 is inconvenient to hook due to its own structural characteristics, therefore, see Figure 1 The integrated disassembly device for the roller bearing system of this embodiment only needs to make a transfer fixture 4 (such as a steel plate with a connecting hole) when disassembling the bearing seat 301. After the transfer fixture 4 is integrally connected to the bearing seat 301 through a threaded part, the clamping claw 203 on the clamping claw mechanism can indirectly hook the bearing seat 301 by hooking on the transfer fixture 4.

[0040] Preferably, see Figure 1 and Figure 2Two lifting supporting platforms 5 are arranged at intervals in each supporting area on the top of the roller placement frame 1. The tops of the two lifting supporting platforms 5 are provided with concave arc grooves 501 for supporting the rollers 3, and the two lifting supporting platforms 5 rise and fall synchronously.

[0041] The setting of the lifting and lowering supporting platform 5 makes the height of the roller 3 adjustable, so that the height of the roller 3 can be adjusted while adjusting the height of the lifting block 202, so as to more quickly reach the state where the clamping mechanism and the lateral ejection mechanism are coaxial with the roller 3; and because the two lifting and lowering supporting platforms 5 in a single supporting area must ensure that the supported roller 3 is in a horizontal and lateral state, the two lifting and lowering supporting platforms 5 in a single supporting area must maintain synchronous lifting; and in order to facilitate the disassembly of the components on the roller 3, a concave arc groove 501 is specially opened, and the groove surface of the concave arc groove 501 is abutted against the arc surface of the roller 3 to prevent the roller 3 from rolling.

[0042] It should be noted that the control of the two lifting platforms 5 in a single supporting area of ​​the roller placement rack 1 can be achieved by electronic control using a single-chip microcomputer or a PLC controller. Since these two electronic control technologies are relatively mature, the specific electronic control implementation method is not required here.

[0043] Preferably, a universal wheel set (not shown in the figure) is installed at the bottom of the roller rack 1, and each universal wheel in the universal wheel set is equipped with a stop lock assembly. The setting of the universal wheel set enables the roller rack 1 to move freely on the horizontal ground of the workshop, which is convenient for adjusting the position of the roller rack 1, and the setting of the stop lock assembly can lock the roller rack 1 when it is idle to ensure safety.

[0044] It should be noted that the universal wheel equipped with a stop-lock assembly is also a mature technology and will not be described in detail here.

[0045] Preferably, see Figure 3 The vertical lifting mechanism includes a lifting rail 204, a lifting block 202 and a lifting drive assembly. The two lifting rails 204 are maintained parallel and spaced apart and erected at the edge position of the top of the frame 201. The lifting block 202 can be freely slidably installed on the two lifting rails 204. The lifting drive assembly is arranged on the frame 201 and is located above the lifting rails 204. A connecting rope 205 is wrapped around the driving end of the lifting drive assembly, and the end of the connecting rope 205 is connected and fixed to the top center of the lifting block 202.

[0046] See also Figure 3When the vertical lifting mechanism is working, the driving end of the lifting drive assembly pulls the connecting rope 205 to move in the direction of the lifting drive assembly, thereby driving the lifting block 202 to gradually rise along the two lifting rails 204. If the driving end of the lifting drive assembly moves in the opposite direction, the lifting block 202 will gradually fall along the two lifting rails 204 under the action of gravity, and the connecting rope 205 will always remain in a straight state.

[0047] Preferably, see Figure 3 The lifting drive assembly includes a driving motor (not shown in the figure) and a fixed pulley block 207. The driving motor is arranged on the frame 201. The fixed pulley block 207 is arranged just above the lifting track 204. The connecting rope 205 is wound around the driving end of the driving motor, and the end of the connecting rope 205 passes through the fixed pulley block 207 and is connected and fixed to the top center of the lifting block 202. The setting of the fixed pulley block 207 makes it unnecessary to set the lifting drive assembly too high, and the height adjustment of the lifting block 202 can also be achieved.

[0048] Preferably, in this embodiment, in order to enhance the connection strength between the driving motor and the lifting block 202 , the connection rope 205 is a steel wire rope.

[0049] Preferably, see Figure 3 The clamp mechanism includes a clamp 203, a telescopic drive assembly (not shown in the figure) and a connecting rod assembly (not shown in the figure). The two clamps 2023 are symmetrically hinged on the lateral side of the lifting block 202 away from the frame 201. The telescopic drive assembly is arranged on the lifting block 202 and located between the two clamps 203. One end of the connecting rod assembly is connected to the driving end of the telescopic drive assembly, and the other end is connected to the two clamps 203 at the same time. When the clamp mechanism is working, the driving end of the telescopic drive assembly moves, and then drives the two clamps 203 to move synchronously through the connecting rod assembly, so as to realize the opening and closing of the two clamps 203.

[0050] Preferably, see Figure 3 The lateral ejection mechanism includes an ejection drive assembly 208 and an ejection shaft 209. The ejection drive assembly 208 is disposed in the lifting block 202, and the ejection end of the ejection drive assembly 208 passes through the lifting block 202 and is disposed away from the lateral side of the frame 201. The ejection shaft 209 is axially fixed on the ejection end of the ejection drive assembly 208. When the lateral ejection mechanism is working, the driving end of the ejection drive assembly 208 is ejected or retracted, thereby driving the ejection shaft 209 to be ejected or retracted synchronously.

[0051] Preferably, see Figure 3In this embodiment, the driving motor on the vertical lifting mechanism adopts a hydraulic motor, the telescopic driving component on the clamping mechanism (not shown in the figure) and the ejection driving component 208 on the horizontal ejection mechanism both adopt hydraulic cylinders, and the frame 201 of the pulling drive frame 2 is equipped with a hydraulic station 210, which supplies oil to the hydraulic motor and two hydraulic cylinders.

[0052] Furthermore, the hydraulic motor and the two hydraulic cylinders are all integrated and controlled through a button box. After the power of the pulling drive frame 2 is turned on, the button box can be used to control the clamping jaw 203 to be loosened, and the height of the clamping jaw 203 can be adjusted so that the clamping jaw mechanism and the lateral ejection mechanism are coaxial with the roller 3, and then the clamping jaw 203 is tightened to hook on the part to be disassembled, and finally the button box is used to control the hydraulic cylinder to drive the ejection shaft 209 to eject, thereby pulling out the part to be disassembled.

[0053] Preferably, see Figure 3 A push-pull handle 211 is installed on the top of the frame 201, and a pair of fixed wheels 212 are installed on the front side of the bottom of the frame 201, and a pair of universal wheels 213 are installed on the rear side of the bottom, and the pair of universal wheels 213 are equipped with a stop and lock assembly. The push-pull handle 211, fixed wheels 212 and universal wheels 213 can facilitate the movement of the pull-out drive frame 2, and the stop and lock assembly can facilitate the movement and locking of the pull-out drive frame 2, which is beneficial to the safety of the workshop.

[0054] In terms of benefit generation, one roller is replaced for each overhaul. After using the device of this embodiment, the working hours are reduced from 4 hours to 2 hours, and the labor is reduced from 8 people to 2 people, which can save costs: (8×4-2×2) / 8 working hours×500 yuan=1750 yuan, and 5 rollers need to be replaced for each overhaul project, which can save a total of 8750 yuan. After the device is manufactured, it can be used for all rollers in the medium and thick plate rolling area. Since 50 rollers need to be replaced on the rollers in the medium and thick plate rolling area every six months, that is, 100 rollers are replaced every year, it can save 175,000 yuan every year.

[0055] In summary, the integrated disassembly device for the roller bearing system of this embodiment can complete the disassembly of the bearings, bearing seats and couplings of rollers of different models, and is simple to operate, highly efficient, and can eliminate safety hazards.

[0056] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principle of the present invention. These improvements and substitutions should also be regarded as the protection scope of the present invention.

Claims

1. An integrated disassembly device for a roller bearing system, characterized in that: The invention comprises a roller placing frame (1) and a drawing drive frame (2), wherein the roller placing frame (1) and the drawing drive frame (2) are both arranged on the horizontal ground of a workshop; a plurality of supporting areas capable of horizontally placing rollers (3) are arranged in parallel and at intervals on the top of the roller placing frame (1); a frame body (201), a vertical lifting mechanism, a clamping mechanism and a horizontal ejection mechanism are provided on the drawing drive frame (2); the vertical lifting mechanism is arranged on the frame body (201), the clamping mechanism and the horizontal ejection mechanism are both arranged on the lifting block (202) of the vertical lifting mechanism, and the horizontal ejection mechanism is located in the interval space between the plurality of clamping jaws (203) on the clamping mechanism.

2. The integrated disassembly device for roller bearing system according to claim 1, characterized in that: Two lifting supporting platforms (5) are arranged at intervals in each supporting area on the top of the roller placement frame (1); the tops of the two lifting supporting platforms (5) are each provided with a concave arc groove (501) for supporting the rollers (3); and the two lifting supporting platforms (5) are lifted and lowered synchronously.

3. The integrated disassembly device for roller bearing system according to claim 2, characterized in that: A universal wheel set is installed at the bottom of the roller placement rack (1), and each universal wheel in the universal wheel set is equipped with a stop locking assembly.

4. The integrated disassembly device for roller bearing system according to claim 1, characterized in that: The vertical lifting mechanism comprises a lifting rail (204), a lifting block (202) and a lifting drive assembly. The two lifting rails (204) are maintained parallel and spaced apart and erected at the edge position of the top of the frame (201). The lifting block (202) can be freely slidably installed on the two lifting rails (204). The lifting drive assembly is arranged on the frame (201) and is located above the lifting rails (204). A connecting rope (205) is wound around the driving end of the lifting drive assembly. The end of the connecting rope (205) is connected and fixed to the top center of the lifting block (202).

5. The integrated disassembly device for roller bearing system according to claim 4, characterized in that: The lifting drive assembly comprises a driving motor and a fixed pulley block (207); the driving motor is arranged on the frame (201); the fixed pulley block (207) is arranged directly above the lifting track (204); the connecting rope (205) is wound around the driving end of the driving motor, and the end of the connecting rope (205) passes around the fixed pulley block (207) and is connected and fixed to the top center of the lifting block (202).

6. The integrated disassembly device for roller bearing system according to claim 1, characterized in that: The clamping mechanism comprises a clamping jaw (203), a telescopic driving assembly and a connecting rod assembly; the two clamping jaws (203) are symmetrically hinged on the lateral side of the lifting block (202) away from the frame (201); the telescopic driving assembly is arranged on the lifting block (202) and located between the two clamping jaws (203); one end of the connecting rod assembly is connected to the driving end of the telescopic driving assembly, and the other end is connected to the two clamping jaws (203) at the same time.

7. The integrated disassembly device for roller bearing system according to claim 1, characterized in that: The lateral ejection mechanism comprises an ejection drive assembly (208) and an ejection shaft (209); the ejection drive assembly (208) is arranged in the lifting block (202), and the ejection end of the ejection drive assembly (208) passes through the lifting block (202) and is arranged away from the lateral side of the frame (201); the ejection shaft (209) is axially fixed on the ejection end of the ejection drive assembly (208).

8. The integrated disassembly device for roller bearing system according to claim 1, characterized in that: A push-pull handle (211) is installed on the top of the frame (201), a pair of directional wheels (212) is installed on the front side of the bottom of the frame (201), and a pair of universal wheels (213) is installed on the rear side of the bottom, and the pair of universal wheels (213) is equipped with a stop locking assembly.