omnidirectional wheels and chassis structure equipped with them

Abstract

This application relates to the field of caster technology, providing a swivel wheel and a chassis structure equipped with it. The swivel wheel includes a mounting top, a wheel seat rotatably connected to the mounting top, and a wheel system rotatably connected to the wheel seat. The wheel system includes a first wheel body and second wheel bodies. The first wheel body has second wheel bodies on both sides along its own axial direction, and the hardness of the first wheel body is less than that of the second wheel body. The swivel wheel provided by this application not only reduces wheel edge wear, thereby reducing the problem of rubber coating peeling, but also reduces the reaction force on the chassis, improving the chassis's operational stability.

Description

Technical Field

[0001] This application relates to the field of caster technology, and in particular to a swivel caster and a chassis structure equipped with it. Background Technology

[0002] The chassis of an AGV (Automated Guided Vehicle) is equipped with casters, which facilitates automatic steering and improves the flexibility of transportation.

[0003] However, because AGVs are typically used to transport heavy objects and require long-term operation, involving a large amount of continuous rotational motion, the casters on AGVs are prone to wear and tear over time, leading to the peeling of the rubber coating. Additionally, sudden changes in stress at the wheel rubber contact surface can create a reaction force on the chassis, resulting in overall instability of the chassis. Utility Model Content

[0004] Therefore, it is necessary to provide a universal wheel that can not only reduce wheel edge wear and thus reduce the problem of rubber coating peeling, but also reduce the reaction force on the chassis and improve the chassis running stability.

[0005] A universal wheel includes a mounting top, a wheel seat rotatably connected to the mounting top, and a wheel system rotatably connected to the wheel seat. The wheel system includes a first wheel body and a second wheel body. The second wheel body is provided on both sides of the first wheel body along its own axial direction. The hardness of the first wheel body is less than the hardness of the second wheel body.

[0006] Understandably, the mounting bracket allows the swivel wheel to be installed in the target position. The wheel seat is rotatably connected to the mounting bracket, and the wheel system is rotatably connected to the wheel seat to ensure the swivel wheel's operational flexibility. Since the first wheel has second wheels on both sides along its axial direction, it's equivalent to using at least three wheels in contact with and supporting the ground, distributing the force as evenly as possible to each wheel and reducing the load on any single wheel. Furthermore, this arrangement places the less rigid first wheel in the center and the harder second wheels on the sides, increasing wheel edge strength and reducing edge wear. The higher edge hardness also reduces frictional resistance during rotation, thus reducing the force on the central first wheel and consequently reducing the reaction force on the chassis. Simultaneously, the lower hardness of the central first wheel ensures the overall grip of the wheel system, reducing the risk of deviation during rotation.

[0007] In some embodiments, the width of the first wheel is greater than the width of the second wheel.

[0008] In some embodiments, the first wheel and the second wheel have a width ratio and a hardness ratio, wherein the ratio of the width ratio to the hardness ratio is between 1.3 and 2.9.

[0009] In some embodiments, the width ratio of the first wheel body to the second wheel body is between 2 and 3.5; and / or, the hardness ratio of the first wheel body to the second wheel body is between 1.2 and 1.5.

[0010] In some embodiments, an assembly gap is provided between the first wheel and the second wheel.

[0011] In some embodiments, the wheel seat includes at least a top plate, the mounting top seat includes a base plate, a mounting shaft and a limiting plate, the mounting shaft passes through the top plate, the base plate and the limiting plate are respectively disposed on both sides of the top plate along the axial direction of the mounting shaft and are both connected to the mounting shaft, a first bearing is provided between the limiting plate and the top plate and between the top plate and the base plate, and the first bearing is sleeved on the outside of the mounting shaft.

[0012] In some embodiments, the caster wheel further includes a first mounting shaft passing through the mounting shaft, with its two ends abutting against opposite sides of the base plate and the limiting plate; and / or, the first bearing is a thrust bearing.

[0013] In some embodiments, the omnidirectional wheel further includes a second assembly shaft connected to the wheel system and the wheel seat, and a second bearing is provided between the first wheel body and / or the second wheel body and the second assembly shaft.

[0014] In some embodiments, the caster wheel further includes a washer, which is provided between the first wheel body and the second wheel body and / or between the second wheel body and the wheel seat. The washer is sleeved on the second assembly shaft and abuts against the inner ring of the second bearing.

[0015] This application also provides a chassis structure, including a chassis body and the aforementioned casters, wherein the casters are mounted on the chassis body via the mounting top seat. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 A schematic diagram of a swivel wheel provided in an embodiment of this application;

[0018] Figure 2An exploded view of a swivel wheel provided in an embodiment of this application;

[0019] Figure 3 This is a front view of a swivel wheel provided in an embodiment of this application;

[0020] Figure 4 A force diagram of the wheel system in a swivel caster provided in an embodiment of this application;

[0021] Figure 5 A partial sectional view of a caster wheel at the first assembly shaft provided in an embodiment of this application;

[0022] Figure 6 This is a partial cross-sectional view of the caster wheel at the second assembly shaft, provided in an embodiment of this application.

[0023] Reference numerals: 10, Assembly top seat; 11, Base plate; 12, Mounting shaft; 13, Limiting plate; 20, Wheel seat; 21, Top plate; 22, Enclosure plate; 30, Wheel system; 31, First wheel body; 32, Second wheel body; 41, First bearing; 42, First assembly shaft; 43, Second assembly shaft; 44, Second bearing; 45, Shim; 101, Through hole; 111, Plate body; 112, Cover body; 113, Assembly protrusion; 201, Assembly space; 301, Assembly gap; 451, First shim; 452, Second shim; 1101, Mounting hole; 2101, Assembly hole. Detailed Implementation

[0024] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0025] It should be noted that when a component is referred to as being "fixed to" or "attached to" another component, it can be directly on the other component or there may be an intermediate component. When a component is considered to be "connected to" another component, it can be directly connected to the other component or there may be an intermediate component present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application's specification are for illustrative purposes only and do not represent the only possible implementation.

[0026] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0027] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature and the second feature are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0028] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used in this application includes any and all combinations of one or more of the associated listed items.

[0029] The casters on AGVs require extensive and continuous rotational movement during use and must bear significant cargo weight. Ideally, when the wheel surface deforms, the contact surface between the wheel and the ground is a deformed rectangular area. After passive rotation, it is compressed into a parallelogram along the direction of rotation, at which point the wheel edge primarily bears shear force. Therefore, in some cases, stress concentration can occur at the deformation point of the wheel, potentially generating extremely high instantaneous shear stress, leading to wheel edge wear and causing the rubber coating on the wheel body to peel off. Simultaneously, the change of the caster from one state to another can cause abrupt changes or oscillations, affecting the stability of the chassis. For example, when the AGV changes from straight-line movement to stationary rotation, if the rotational speed is high, the large torque required to overcome static friction can cause abrupt changes in the caster. For example, since the bottom of the AGV is also equipped with drive wheels, when there is a certain deviation between the direction of travel of the omnidirectional wheel and the direction of travel of the drive wheel, the start of the drive wheel will cause the omnidirectional wheel to generate a reverse deflection torque in the direction of travel of the drive wheel. If the rotation speed is large at this time, it may oscillate with the direction of travel as the baseline.

[0030] Based on this, one embodiment of this application provides a caster wheel that not only reduces wheel edge wear, thereby alleviating the problem of rubber coating peeling off, but also reduces the reaction force on the chassis, improving the chassis's operational stability. The specific structure of this caster wheel is described in detail below.

[0031] Please see Figures 1 to 3 For example, the universal wheel includes a mounting top seat 10, a wheel seat 20 rotatably connected to the mounting top seat 10, and a wheel system 30 rotatably connected to the wheel seat 20. The wheel system 30 includes a first wheel body 31 and a second wheel body 32. The first wheel body 31 has the second wheel body 32 on both sides along its own axial direction. The hardness of the first wheel body 31 is less than the hardness of the second wheel body 32.

[0032] Understandably, the mounting top 10 may require a target location for installing casters. For example, the mounting top 10 can be fixed to the chassis (i.e., the chassis body below) with screws to achieve the assembly of the casters and the chassis. The wheel seat 20 is rotatably connected to the mounting top 10, and the wheel system 30 is rotatably connected to the wheel seat 20. The axes of the two rotating shafts are angled; for example, the axis of rotation between the wheel seat 20 and the mounting top 10 is vertical (i.e., the Z-axis direction). Figure 2 The vertical direction within; and, the axis of rotation between the gear train 30 and the wheel seat 20 is along the X-axis direction, for example... Figure 2 In the left and right directions. In this way, the wheel system 30 can rotate relative to the wheel seat 20, and the wheel seat 20 can drive the wheel system 30 to rotate relative to the mounting top seat 10, thereby satisfying the 360° rotation flexibility of the caster.

[0033] When the caster wheel is stationary, the contact surface between the wheel system 30 and the ground can be approximated as a rectangular area. After being subjected to torque and rotating around the center of rotation, the rectangular area deforms under the reaction force from the ground. Figure 4 The stress on the left side of the upper boundary line is mainly compressive stress, and the stress on the right side is mainly tensile stress; and the stress on the left side of the lower boundary line is mainly tensile stress, and the stress on the right side is mainly compressive stress; the part near the middle bears shear stress.

[0034] In related technologies, the wheels of casters are usually made of relatively soft materials, which leads to severe deformation of the wheels when subjected to force, and the stress concentration phenomenon is more obvious. This results in a short lifespan for the wheels, and the sudden force changes caused by the installation of casters make them prone to fatigue failure.

[0035] At this point, because the first wheel 31 has second wheels 32 on both sides along its own axial direction, for example, one second wheel 32 can be provided on each of the left and right sides of the first wheel 31. This effectively utilizes at least three wheels in contact with the ground, distributing the force on the wheel system 30 as evenly as possible to each wheel, reducing the load on any single wheel. Furthermore, since the harder second wheel 32 is located on the side, it increases the edge strength of the wheel system 30 at both sides, reducing the deformation on both sides and thus reducing edge wear. The higher edge hardness also reduces frictional resistance during rotation, thereby reducing the force on the central first wheel 31 and reducing the reaction force on the chassis. Simultaneously, because the less hard first wheel 31 is located in the center, it ensures the overall grip of the wheel system, reducing the risk of deviation during rotation.

[0036] Please see Figures 1 to 3 In some specific embodiments, a second wheel body 32 is provided on each side of the first wheel body 31 along its own axial direction. That is, the wheel system 30 consists of three wheel bodies, and the first wheel body 31 and the two second wheel bodies 32 are coaxially assembled.

[0037] Alternatively, two second wheels 32 can be provided on each side of the first wheel 31 along its own axial direction, i.e., the second wheels 32 are arranged in pairs to ensure that the force is evenly distributed on both sides of the first wheel 31. This is only an example.

[0038] Please see Figures 1 to 3 In some embodiments, the width of the first wheel 31 is greater than the width of the second wheel 32. That is, the first wheel 31, with lower hardness and greater width, is located in the center, while the second wheel 32, with higher hardness and smaller width, is located on both sides. This arrangement allows the wider, softer first wheel 31 to bear the main load, fully utilizing its advantages in shock absorption and strong grip. Furthermore, the narrower, stiffer second wheel 32 effectively provides wheel edge protection and guidance, significantly reducing rotational friction resistance. Thus, the overall load distribution and stress state of the wheel system 30 are optimized under load, reducing the risk of excessive internal stress at the contact surface due to the excessive width of the second wheel 32. This reduces wheel edge wear and reaction force on the chassis, while improving grip and operational stability.

[0039] In some embodiments, the first wheel body 31 and the second wheel body 32 have a width ratio and a hardness ratio, wherein the ratio of the width ratio to the hardness ratio is between 1.3 and 2.9.

[0040] Wherein, the width of the first wheel 31 is D, the hardness of the first wheel 31 is H, the width of the second wheel 32 is d, the hardness of the second wheel 32 is h, and the ratio between the width of the first wheel 31 and the width of the second wheel 32 is called the width ratio i. dThe ratio between the hardness of the first wheel 31 and the hardness of the second wheel 32 is called the hardness ratio i. h The details are as follows:

[0041] ;

[0042] .

[0043] Therefore, the ratio k of the width ratio and the hardness ratio is:

[0044] .

[0045] The value of the ratio k ranges from 1.3 to 2.9. That is, the width ratio is greater than the hardness ratio, thus ensuring that while the first wheel body 31 is relatively wide and the second wheel body 32 is relatively narrow, the first wheel body 31 has a lower hardness and the second wheel body 32 has a higher hardness. This arrangement can effectively distribute the vertical load borne by the wheel system 30 in the vertical direction to the wide and soft first wheel body 31, reducing the risk of premature wear or even damage to the narrow and hard second wheel body 32 due to excessive local pressure. Moreover, this arrangement can also effectively reduce the rotational friction resistance of the second wheel body 32 while ensuring that the first wheel body 31 provides sufficient grip, achieving a balance between grip and low resistance, and reducing the reaction force on the chassis.

[0046] In some specific embodiments, the ratio k of the width ratio and the hardness ratio can be 1.3, 1.5, 1.8, 2, 2.3, 2.6, 2.9, etc.

[0047] Please see Figures 1 to 3 In some embodiments, the width ratio of the first wheel 31 and the second wheel 32 is between 2 and 3.5. That is, i d The value ranges from 2 to 3.5. This configuration ensures that the width of the first wheel 31 is not too large and the width of the second wheel 32 is not too small. This allows the first wheel 31 to bear a significant vertical load, while the two second wheels 32 share some of the load, reducing the deformation of the first wheel 31. Furthermore, this configuration ensures that the second wheel 32 has a relatively small contact area with the ground, resulting in lower rotational resistance, improved protection for the second wheel 32, reduced wheel edge wear and rubber coating detachment, and decreased reaction force on the chassis.

[0048] In some specific embodiments, the width ratio i of the first wheel body 31 and the second wheel body 32 is... d It can be 2, 2.3, 2.5, 2.8, 3, 3.2, 3.5, etc.

[0049] Furthermore, the hardness ratio of the first wheel 31 and the second wheel 32 is between 1.2 and 1.5. That is to say, i h The value ranges from 1.2 to 1.5. This setting ensures that while the second wheel 32 has a relatively high hardness, it reduces the risk of excessive reaction force on the chassis due to excessive hardness of the second wheel 32, thereby improving the stability of the chassis; and ensures that while the first wheel 31 has a relatively low hardness, it also has a certain supporting performance, which facilitates better shock absorption and grip.

[0050] In some specific embodiments, the hardness ratio i h It can be 1.2, 1.25, 1.3, 1.35, 1.4, 1.45, 1.5, etc.

[0051] In some other specific embodiments, the ratio k of the width ratio to the hardness ratio is 2.5, and the hardness ratio is 1.4.

[0052] In some embodiments, the hardness of the first wheel body 31 is between 70HA and 80HA. This setting avoids the problems of excessive deformation under stress, stress concentration, significantly increased rolling resistance, and low load-bearing capacity caused by an overly soft first wheel body 31; at the same time, it also avoids the problems of weakened cushioning capacity and increased reaction force on the chassis caused by an overly hard first wheel body 31. For example, the hardness of the first wheel body 31 can be 70HA, 72HA, 74HA, 76HA, 78HA, 80HA, etc.

[0053] Furthermore, the hardness of the second wheel body 32 is between 80HA and 100HA. This setting avoids the problem of increased rotational resistance and easy wear caused by an excessively soft second wheel body 32; and it also avoids the problem of increased reaction force on the chassis caused by an excessively hard second wheel body 32. For example, the hardness of the second wheel body 32 can be 80HA, 85HA, 88HA, 90HA, 94HA, 96HA, 100HA, etc.

[0054] In some specific embodiments, the hardness of the first wheel body 31 is 75HA, and the hardness of the second wheel body 32 is 95HA. In this case, the hardness ratio between the two is approximately 1.27.

[0055] Please see Figure 3 and Figure 6In some embodiments, an assembly gap 301 is provided between the first wheel body 31 and the second wheel body 32. This arrangement can prevent the first wheel body 31 and the second wheel body 32 from directly contacting each other and provide a certain deformation space for their deformation under force, thereby reducing wear between them. Moreover, this arrangement allows the wheel system 30 to generate deflection displacement when turning, so that the same force is spread to more areas as much as possible, thereby reducing the tensile, compressive and shear stresses on the deformation surface of the wheel system, and further reducing the peeling of the surface of the second wheel body 32.

[0056] Please see Figure 1 , Figure 2 and Figure 5 In some embodiments, the wheel seat 20 includes at least a top plate 21, and the mounting top seat 10 includes a base plate 11, a mounting shaft 12, and a limiting plate 13. The mounting shaft 12 passes through the top plate 21. The base plate 11 and the limiting plate 13 are respectively disposed on both sides of the top plate 21 along the axial direction of the mounting shaft 12 and are both connected to the mounting shaft 12. A first bearing 41 is provided between the limiting plate 13 and the top plate 21, and between the top plate 21 and the base plate 11. The first bearing 41 is sleeved on the outside of the mounting shaft 12.

[0057] Specifically, the wheel seat 20 also includes a baffle plate 22 connected to the top plate 21. The bottom of the baffle plate 22 and at least one side along the Y-axis are open. The baffle plate 22 and the top plate 21 together form an assembly space 201 for accommodating a portion of the wheel system 30, with the other part of the wheel exposed from the aforementioned opening. The top plate 21 has an assembly hole 2101 for the mounting shaft 12 to pass through. The wall of the assembly hole 2101 is clearance-fitted with the outer wall of the mounting shaft 12. The top plate 21 can rotate around the axis of the mounting shaft 12, thereby satisfying the rotation of the wheel seat 20 relative to the mounting top seat 10. The mounting shaft 12 serves as the pivot between the wheel seat 20 and the mounting top seat 10. The limiting plate 13 is located on the side of the top plate 21 facing the wheel system 30, and the base plate 11 is located on the side of the top plate 21 away from the wheel system 30. The base plate 11 is used for connection to the chassis. Because a first bearing 41 is provided between the limiting plate 13 and the top plate 21, and between the top plate 21 and the base plate 11, it can provide support and improve the reliability and strength of the connection. In other words, the load in the vertical direction can be borne by the two first bearings 41. The upper first bearing 41 mainly bears the gravity, while the lower first bearing 41 is mainly used to ensure the smooth rotation of the wheel system 30 when the caster is bumpy.

[0058] like Figure 5 As shown, the substrate 11 includes a plate 111 and a cover 112, which are welded together. The cover 112 is spherically shaped in the direction away from the plate 111. A mounting protrusion 113 is provided on the side of the cover 112 away from the plate 111, and a first bearing 41 is provided between the mounting protrusion 113 and the top plate 21.

[0059] Furthermore, the first bearing 41 is a thrust bearing. The thrust bearing is mainly used to bear axial loads and includes two races, a cage located between the two races, and multiple balls. The two races can respectively abut against the top plate 21 and the limiting plate 13, or respectively abut against the top plate 21 and the mounting protrusion 113. The cooperation of two thrust bearings arranged axially spaced along the mounting shaft 12 allows for the bearing of larger axial loads, resulting in more stable rotation and extended service life.

[0060] In some specific embodiments, the first bearing 41 is a thrust ball bearing, which only bears axial loads.

[0061] Please see Figure 1 , Figure 2 and Figure 5 Furthermore, the caster wheel also includes a first mounting shaft 42, which passes through the mounting shaft 12, and its two ends abut against the opposite sides of the base plate 11 and the limiting plate 13, respectively. In other words, the first mounting shaft 42 further strengthens the connection between the wheel seat 20 and the mounting top seat 10. The opposite sides of the base plate 11 and the limiting plate 13 are both provided with recesses for limiting the ends of the first mounting shaft 42. The mounting top seat 10 has a through hole 101 extending axially along the mounting shaft 12, and the first mounting shaft 42 passes through this through hole 101. The two ends of the first mounting shaft 42 have limiting protrusions that respectively limit and cooperate with the opposite sides of the top plate 21 and the limiting plate 13.

[0062] Please see Figure 1 , Figure 2 and Figure 6 In some embodiments, the omnidirectional wheel further includes a second mounting shaft 43 connecting the wheel train 30 and the wheel seat 20. Second bearings 44 are provided between the first wheel body 31 and the second mounting shaft 43, and between the second wheel body 32 and the second mounting shaft 43, to provide rotational support. The second mounting shaft 43 serves as the pivot for the wheel train 30 to rotate relative to the wheel seat 20. Specifically, each wheel body (i.e., each first wheel body 31 and each second wheel body 32) may have two second bearings 44 spaced apart along the wheel body axial direction, with the two second bearings 44 located near the two ends of the wheel body.

[0063] Alternatively, there could be two spaced second bearings 44 between the first wheel body 31 and the second assembly shaft 43, with the two second wheel bodies 32 connected to the second assembly shaft 43 via bushings. Or, there could be only two second bearings 44 between the two second wheel bodies 32 and the second assembly shaft 43, with the first wheel body 31 connected to the second assembly shaft 43 via bushings. This is merely an example.

[0064] Both the first assembly shaft 42 and the second assembly shaft 43 can be made of pins.

[0065] like Figure 2 and Figure 6 As shown, the omnidirectional wheel further includes a washer 45. A washer 45 is provided between the first wheel body 31 and the second wheel body 32, and also between the second wheel body 32 and the wheel seat 20. The washer 45 is fitted onto the second assembly shaft 43 and abuts against the inner ring of the second bearing 44. For ease of description, the first washer 451 corresponds to the space between the first wheel body 31 and the second wheel body 32, and the second washer 452 corresponds to the space between the second wheel body 32 and the wheel seat 20.

[0066] Understandably, the presence of a first shim 451 between the first wheel body 31 and the second wheel body 32 satisfies the requirement for an assembly gap 301 between them, thereby reducing wear and interference. The first wheel body 31 has first shims 451 on both sides along the axial direction of the second assembly shaft 43 to ensure an assembly gap 301 between it and each second wheel body 32. Two second wheel bodies 32 have second shims 452 on the side of each second wheel body 32 facing away from the first wheel body 31 along the axial direction of the second assembly shaft 43. The second shims 452 are pressed between the second wheel body 32 and the retaining plate 22 of the wheel seat 20. This arrangement promotes a gap between the second wheel body 32 and the wheel seat 20, reducing wear and improving the protection of the second wheel body 32. Simultaneously, the shim 451 also acts as a limiting element in the assembly of the second bearing 44. The inner ring of the second bearing 44 abuts against the shim 45, reducing axial movement of the second bearing 44 along the second assembly shaft 43.

[0067] Please see Figure 1 and Figure 2 This application also provides a chassis structure, including a chassis body and the aforementioned casters, the casters being mounted on the chassis body via a mounting top 10.

[0068] Specifically, the base plate 11 of the mounting top 10 has multiple mounting holes 1101 spaced apart along its circumference, which can be used to fix it to the chassis body with screws passing through the mounting holes 1101. When the cross-section of the base plate 11 is square or rectangular, a mounting hole 1101 can be provided at each of the four apex corners. The chassis body can be provided with at least two spaced casters, and at least two drive wheels are also connected to the bottom of the chassis body. The movement of the chassis structure is realized by the cooperation of the drive wheels and the casters, which can meet the needs of cargo handling or transportation. It is precisely because of the setting of the first wheel body 31 and the second wheel body 32 in the casters that the wear and rubber peeling of the caster wheel system 30 at the wheel edge can be reduced during the handling process, and the reaction force on the chassis body can be reduced, thereby improving the running stability of the chassis body.

[0069] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0070] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. Therefore, the patent protection scope of this application should be determined by the appended claims.

Claims

1. A universal wheel, characterized in that, The assembly includes a mounting top seat (10), a wheel seat (20) rotatably connected to the mounting top seat (10), and a wheel system (30) rotatably connected to the wheel seat (20). The wheel system (30) includes a first wheel body (31) and a second wheel body (32). The first wheel body (31) has the second wheel body (32) on both sides along its own axial direction. The hardness of the first wheel body (31) is less than the hardness of the second wheel body (32).

2. The universal wheel according to claim 1, characterized in that, The width of the first wheel (31) is greater than the width of the second wheel (32).

3. The universal wheel according to claim 2, characterized in that, The first wheel body (31) and the second wheel body (32) have a width ratio and a hardness ratio, wherein the ratio of the width ratio and the hardness ratio is between 1.3 and 2.

9.

4. The caster wheel according to claim 2 or 3, characterized in that, The width ratio of the first wheel (31) to the second wheel (32) is between 2 and 3.5; and / or, The hardness ratio of the first wheel body (31) and the second wheel body (32) is between 1.2 and 1.

5.

5. The universal wheel according to claim 1, characterized in that, An assembly gap (301) is provided between the first wheel body (31) and the second wheel body (32).

6. The universal wheel according to claim 1, characterized in that, The wheel seat (20) includes at least a top plate (21). The mounting top seat (10) includes a base plate (11), a mounting shaft (12), and a limiting plate (13). The mounting shaft (12) passes through the top plate (21). The base plate (11) and the limiting plate (13) are respectively disposed on both sides of the top plate (21) along the axial direction of the mounting shaft (12) and are both connected to the mounting shaft (12). A first bearing (41) is provided between the limiting plate (13) and the top plate (21), and between the top plate (21) and the base plate (11). The first bearing (41) is sleeved on the outside of the mounting shaft (12).

7. The universal wheel according to claim 6, characterized in that, The caster wheel also includes a first assembly shaft (42), which passes through the mounting shaft (12). The two ends of the first assembly shaft (42) abut against opposite sides of the base plate (11) and the limiting plate (13); and / or, The first bearing (41) is a thrust bearing.

8. The caster wheel according to claim 1 or 7, characterized in that, The omnidirectional wheel also includes a second assembly shaft (43) connected to the wheel system (30) and the wheel seat (20), and a second bearing (44) is provided between the first wheel body (31) and / or the second wheel body (32) and the second assembly shaft (43).

9. The universal wheel according to claim 8, characterized in that, The universal wheel also includes a gasket (45), which is provided between the first wheel body (31) and the second wheel body (32) and / or between the second wheel body (32) and the wheel seat (20). The gasket (45) is sleeved on the second assembly shaft (43) and abuts against the inner ring of the second bearing (44).

10. A chassis structure, characterized in that, It includes a chassis body and a caster wheel as described in any one of claims 1 to 9, wherein the caster wheel is disposed on the chassis body via the mounting top seat (10).

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