Directional industrial trundle for mobile welding platform and performance curve calculation method thereof

Abstract

The invention relates to the technical field, in particular to a directional industrial trundle for a movable welding platform and a performance curve calculation method thereof.The directional industrial trundle comprises a trundle upper plate used for supporting the welding platform, a trundle upper support is arranged below the trundle upper plate, and an upper support boss is arranged on the trundle upper support; the trundle lower support is connected with the trundle upper support in a sliding mode, and a round wheel is connected into the trundle lower support through a bearing in a rolling mode. The shock absorber is connected to the trundle lower support through a mounting bolt, and the upper end of the shock absorber is tightly close to the top support boss; the multi-stage vibration reduction system is adopted, the pre-pressing spring, the bearing spring and the vibration reduction valve have the synergistic effect, and the excellent vibration reduction effect is achieved while the high bearing capacity is kept; meanwhile, the stability of the moving direction is ensured by adopting a sliding connection structure and a rigid constraint design, the offset of the welding platform in the moving process is reduced, and the welding precision is greatly improved; the long-standing technical problem that high bearing and excellent vibration reduction are difficult to consider at the same time in the field of industrial casters is solved.

Description

Technical Field

[0001] This invention relates to the technical field, specifically to a directional industrial caster for a mobile welding platform and a method for calculating its performance curve. Background Technology

[0002] In the steel structure processing and manufacturing field, with the rapid development of welding automation technology, the application of welding robots is becoming increasingly widespread. To improve operational flexibility, welding robots are usually mounted on mobile platforms equipped with casters for easy movement between different workstations. However, industrial sites often have uneven surfaces, causing significant up-and-down vibrations of the mobile platform during movement. This vibration has a serious impact on welding quality: on the one hand, welding robots rely on high-precision servo motors and encoders for accurate motion control, and platform vibration can cause the robotic arm to deviate in positioning; on the other hand, deviations in the welding path directly affect the weld formation quality, and in severe cases, may result in welding defects such as incomplete penetration and undercut.

[0003] Currently, common industrial caster systems on the market mainly suffer from the following technical defects: 1. Lack of effective vibration reduction design: Traditional casters use a rigid connection structure, which cannot effectively filter vibrations caused by uneven ground; 2. Conflict between load-bearing and vibration reduction: Existing vibration-damping casters often sacrifice load-bearing capacity when increasing vibration reduction performance, making it difficult to meet the needs of heavy welding equipment; 3. Insufficient directional stability: Ordinary swivel casters are prone to directional deviation during vibration reduction, affecting the accuracy of the welding path.

[0004] Therefore, there is an urgent need to develop an industrial caster that combines high load-bearing capacity and excellent vibration reduction performance, which can effectively isolate the transmission of ground vibration to the welding platform while maintaining the directional stability of the moving platform. This is of great significance for improving the quality of automated welding. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this invention is to provide a directional industrial caster for a mobile welding platform that can effectively isolate the transmission of ground vibration to the welding platform while maintaining the directional stability of the mobile platform, and a method for calculating the performance curve of the caster.

[0006] The technical solution adopted by this invention to solve its technical problem is:

[0007] A directional industrial caster for a mobile welding platform includes: an upper caster plate for supporting the welding platform; an upper caster bracket disposed below the upper caster plate, the upper caster bracket having an upper bracket boss; a lower caster bracket slidably connected to the upper caster bracket, the lower caster bracket having bearing roller holes; a wheel placed inside the lower caster bracket and connected to the lower caster bracket via bearing rollers; and a shock absorber connected to the lower caster bracket via mounting bolts, the upper end of the shock absorber tightly abutting against the upper bracket boss.

[0008] As a preferred embodiment, a further technical solution of the present invention is:

[0009] Preferably, the vibration damper includes a lower housing, a constraint housing, and an upper housing. A load-bearing spring is provided on the lower housing. An upper support plate is also provided on the upper side of the upper housing. A through hole corresponding to the load-bearing spring is provided on the upper housing, through which the load-bearing spring passes and connects to the upper support plate. A vertical guide rod is also provided on the upper support plate, and a guide rod limiting hole is provided on the upper housing, through which the vertical guide rod passes.

[0010] Preferably, the vibration damper further includes a vibration damping housing, a transmission guide rod, and a vibration damper intermediate plate; the vibration damping housing includes a vibration damping housing constraint unit disposed on the vibration damping housing constraint shell, a vibration damping valve is slidably disposed in the vibration damping housing constraint unit, a preload spring is disposed on one side of the vibration damping valve, the preload spring abuts against the inner wall of the vibration damping housing constraint unit, and a vibration damping valve limiting groove is machined on the other side of the vibration damping valve; the vibration damper intermediate plate is located in the vibration damping housing constraint shell, and a through hole for a bearing spring is opened in the middle, the lower end of the vertical guide rod is connected to the vibration damper intermediate plate, and a limiting groove is cut on the side of the vibration damper intermediate plate; the end of the transmission guide rod is a cylindrical head, one end is located in the limiting groove of the intermediate plate, and the other end is embedded in the limiting groove of the vibration damping valve.

[0011] Preferably, the inner wall of the vibration damping box constraint unit is provided with a first preload spring limiting groove, and the vibration damping valve is provided with a second preload spring limiting groove. One end of the preload spring is engaged in the first preload spring limiting groove, and the other end is engaged in the second preload spring limiting groove.

[0012] Preferably, a lower fixing buckle for the bearing spring is provided in the middle of the lower housing of the shock absorber, and an upper fixing buckle for the bearing spring is provided at the bottom of the upper bearing plate of the shock absorber. The upper end of the bearing spring is engaged in the upper fixing buckle for the bearing spring, and the lower end is engaged in the lower fixing buckle for the bearing spring.

[0013] Preferably, the upper plate of the caster is a rectangular connecting plate with caster mounting holes, and the upper plate of the caster is connected to the welding platform through the caster mounting holes.

[0014] Preferably, the upper bracket of the caster is provided with an upper bracket elongated hole, and the lower bracket of the caster is provided with a lower bracket elongated hole, and the upper bracket and the lower bracket of the caster are slidably connected through the upper bracket elongated hole and the lower bracket elongated hole.

[0015] This invention also discloses a method for calculating the performance curve of directional industrial casters for mobile welding platforms. The method utilizes directional industrial casters for mobile welding platforms, and the specific steps are as follows:

[0016] S1: Establish the equation for the virtual work principle of the vibration damper:

[0017] Fx-2F h tan(β)δx=F Y δx-2F h tan(β)δx=0 (1);

[0018] In the formula, x represents the vertical displacement of the bearing plate on the damper relative to its equilibrium position; F h β is the horizontal spring force of the preloaded spring; β is the angle between the transmission guide rod and the horizontal line; F Y F represents the force required to eliminate the restoring force of the load-bearing spring external damper; F represents the external force required to eliminate the load-bearing spring external damper.

[0019] S2: Determine the restoring force of the preloaded spring:

[0020] F h =K h (L0-L ry (2);

[0021] In the formula, L ry L0 is the actual length of the preload spring at any working position during the working stroke of the shock absorber; K is the original length of the preload spring. h This refers to the preload spring stiffness;

[0022] S3: Calculate the angle between the transmission guide rod and the horizontal line:

[0023] tan(β)=(h sjj -x)(bL ry ) -1 (3);

[0024] In the formula, h sjj 1 is the vertical distance from the reference plane of the upper bearing plate of the shock absorber to the geometric center line of the preload spring; b is the shortest horizontal distance between the inner wall of the shock absorber constraint housing and the side surface of the shock absorber intermediate plate near the preload spring.

[0025] S4: Calculate the perpendicular distance from the reference plane of the upper bearing plate of the shock absorber to the geometric center line of the preload spring:

[0026]

[0027] In the formula, 'a' is the length of the transmission guide rod;

[0028] S5: Calculate the actual length of the preloaded spring at any working position during the working stroke of the shock absorber:

[0029]

[0030] S6: Substitute equations (2)-(5) into equation (1) to obtain the overall restoring force equation of the damper;

[0031]

[0032] S7: Differentiate x in the overall restoring force equation of the damper to obtain the stiffness curve equation of the damper;

[0033] S8: Integrating the load-bearing springs yields the overall restoring force equation and stiffness-displacement equation for a single vibration damper.

[0034] Preferably, step S7 specifically includes:

[0035] make:

[0036] δ1=b-L0 (7);

[0037] δ2=a 2 -δ1 2 (8);

[0038]

[0039] Equation (6) can be simplified to:

[0040]

[0041] Differentiating x, we obtain the stiffness curve equation of the vibration damper:

[0042]

[0043] Preferably, S8: Integrating the load-bearing springs to obtain the overall restoring force equation F for a single shock absorber. JZ and stiffness displacement equation K JZ

[0044]

[0045] Where: K CZ This is to support the stiffness of the spring.

[0046] The present invention, which adopts the above technical solution, has the following prominent features compared with the prior art:

[0047] This mobile welding platform uses directional industrial casters suitable for precision equipment such as automated welding robots. Through an innovative vibration damper structure design, it effectively isolates vibrations caused by uneven ground, reducing impact on the welding platform and thus improving welding quality. The vibration damper structure optimizes the synergistic effect of the load-bearing spring and the preload spring, maintaining vibration reduction performance while ensuring high load-bearing capacity, making it suitable for heavy-duty welding equipment. It solves the technical problems of insufficient vibration reduction and the contradiction between load-bearing capacity and stability in traditional casters, significantly improving the reliability and efficiency of industrial applications. Furthermore, this application provides a method for calculating the performance curve by deriving the restoring force equation and stiffness curve equation of the vibration damper, facilitating parameter optimization during the design phase to meet the needs of different working conditions. Attached Figure Description

[0048] Figure 1 This is a schematic diagram of the structure of the directional industrial caster in an embodiment of the present invention;

[0049] Figure 2 This is a schematic diagram of the other side of the directional industrial caster in an embodiment of the present invention;

[0050] Figure 3 This is an isometric view of the vibration damper in an embodiment of the present invention;

[0051] Figure 4 This is a front view of the vibration damper in an embodiment of the present invention.

[0052] Figure 5 This is a partial cross-sectional view of the vibration damper in an embodiment of the present invention;

[0053] Figure 6 This is a top view of the vibration damper in an embodiment of the present invention;

[0054] Figure 7 The above is a performance curve of the shock absorber in a single directional industrial caster in an embodiment of the present invention;

[0055] Figure 8 for Figure 7 A diagram showing the state of the directional industrial caster at point P.

[0056] Figure 9 This is a schematic diagram of the structure of the shock absorber during operation in an embodiment of the present invention;

[0057] Figure 10 Assembling some parts of the vibration damper in the embodiments of the present invention. Figure 1 ;

[0058] Figure 11 This is a schematic diagram of the lower housing of the vibration damper in an embodiment of the present invention;

[0059] Figure 12 This is a schematic diagram of the upper housing of the vibration damper in an embodiment of the present invention;

[0060] Figure 13 This is a schematic diagram of the vertical guide rod in an embodiment of the present invention;

[0061] Figure 14 This is a schematic diagram of the middle plate of the vibration damper in an embodiment of the present invention;

[0062] Figure 15 This is a front view of the middle plate of the vibration damper in an embodiment of the present invention;

[0063] Figure 16 This is an isometric view of the middle plate of the vibration damper in an embodiment of the present invention;

[0064] Figure 17 This is a front view of the upper bearing plate of the vibration damper in an embodiment of the present invention;

[0065] Figure 18 This is an isometric view of the bearing plate on the damper in an embodiment of the present invention;

[0066] Figure 19 Assembling some parts of the vibration damper in the embodiment of the present invention. Figure 2 ;

[0067] Figure 20 Assembling some parts of the vibration damper in the embodiment of the present invention. Figure 3 ;

[0068] Figure 21 This is a front view of the transmission guide rod in an embodiment of the present invention;

[0069] Figure 22 for Figure 21 Cross-sectional view at point AA;

[0070] Figure 23 This is a schematic diagram of the vibration damping box structure in an embodiment of the present invention;

[0071] Figure 24 This is a top view structural diagram of the vibration damping box in an embodiment of the present invention;

[0072] Figure 25 for Figure 24 Cross-sectional view at point BB;

[0073] Figure 26 This is an assembly of some parts of the vibration damping box in an embodiment of the present invention;

[0074] Figure 27 for Figure 2 A detailed magnified view of the area at position I in the middle;

[0075] Figure 28 Assembling some parts of the directional industrial caster in this embodiment of the invention. Figure 1 ;

[0076] Figure 29Assembling some parts of the directional industrial caster in this embodiment of the invention. Figure 2 ;

[0077] Figure 30 Assembling some parts of the directional industrial caster in this embodiment of the invention. Figure 3 ;

[0078] Figure 31 Assembling some parts of the directional industrial caster in this embodiment of the invention. Figure 4 ;

[0079] Figure 32 for Figure 31 A detailed enlarged view of the middle II position;

[0080] Figure 33 This is a schematic diagram of the structure of the caster lower bracket in an embodiment of the present invention;

[0081] Figure 34 This is a schematic diagram illustrating the application scenario of directional industrial casters in an embodiment of the present invention;

[0082] Figure 35 for Figure 34 A detailed enlarged view of a section at position III;

[0083] Figure 36 This is a schematic diagram of the shock absorber in motion according to an embodiment of the present invention;

[0084] Figure 37 This is a schematic diagram of the vibration damping principle of the vibration damper in an embodiment of the present invention.

[0085] Explanation of reference numerals in the attached drawings: 1. Vibration damper; 11. Lower housing of vibration damper; 111. Mounting hole of lower housing of vibration damper; 112. Lower fixing buckle of bearing spring; 12. Constraint housing of vibration damper; 13. Upper housing of vibration damper; 131. Through hole of upper housing of vibration damper; 132. Guide rod limiting hole; 14. Upper bearing plate of vibration damper; 141. Upper fixing buckle of bearing spring; 142. Mounting hole of guide rod of upper bearing plate; 15. Vertical guide rod; 151. Thread; 152. Nut; 16. Vibration damping box; 161. Vibration damping valve; 1611. Limiting groove of vibration damping valve; 1612. Limiting groove of second preload spring. 162. Preload spring; 163. Vibration damper housing constraint unit; 1631. First preload spring limiting groove; 17. Transmission guide rod; 18. Vibration damper intermediate plate; 181. Intermediate plate through hole; 182. Intermediate plate limiting groove; 183. Intermediate plate threaded hole; 184. Intermediate plate limiting groove; 19. Bearing spring; 2. Caster upper plate; 21. Caster mounting hole; 3. Caster upper bracket; 31. Upper bracket oblong hole; 32. Upper bracket boss; 4. Round wheel; 5. Bearing roller; 6. Caster lower bracket; 61. Bearing roller hole; 62. Lower bracket oblong hole; 7. Mounting bolt; 8. Welding platform. Detailed Implementation

[0086] The present invention will be further illustrated below with reference to specific embodiments. The purpose of this illustration is solely to provide a better understanding of the invention. Therefore, the examples given do not limit the scope of protection of the present invention.

[0087] like Figures 1 to 37 As shown in the figure, this embodiment provides a directional industrial caster for a mobile welding platform, including: a caster upper plate 2, which is a rectangular connecting plate with a caster mounting hole 21, and is connected to the welding platform 8 through the caster mounting hole 21; a caster upper bracket 3, which is welded and fixed to the bottom of the caster upper plate 2, and has an upper bracket boss 31; a caster lower bracket 6, which is slidably connected to the caster upper bracket 3, and has a bearing rolling hole 61 with a bearing roller 5 installed in the bearing rolling hole 61; a wheel 4, which is placed inside the caster lower bracket 6 and connected to the caster lower bracket 6 through the bearing roller 5; and a shock absorber 1, which is connected to the caster lower bracket 6 through mounting bolts, with the upper end of the shock absorber 1 tightly pressing against the upper bracket boss 31.

[0088] Furthermore, the shock absorber includes a lower housing 11, a constraint housing 12 on the lower housing 11, and an upper housing 13 on the constraint housing 12. A lower fixing buckle 112 for a load-bearing spring is located in the middle of the lower housing 11, and a load-bearing spring 19 is engaged with the lower fixing buckle 112. The inner diameter of the lower fixing buckle 112 matches the outer diameter of the load-bearing spring 19, allowing the outer side of the load-bearing spring 19 to fit tightly against the inner diameter of the lower fixing buckle 112. The lower housing 11 also has a mounting hole 111, through which the lower housing 11 can be connected to the lower caster bracket 6 via mounting bolts 7. The constraint housing 12 is a box-shaped structure with openings at both ends.

[0089] The upper side of the upper housing 13 of the shock absorber is also provided with an upper bearing plate 14 of the shock absorber; the upper housing 13 of the shock absorber is provided with a through hole 131 of the upper housing of the shock absorber corresponding to the bearing spring 19, the bearing spring 19 passes through the through hole 131 of the upper housing of the shock absorber, and the bottom of the upper bearing plate 14 of the shock absorber is provided with a fixing buckle 141 of the bearing spring, and the upper end of the bearing spring 19 is engaged in the fixing buckle 141 of the bearing spring.

[0090] It also includes a vertical guide rod 15, one end of which is provided with a thread 151 and the other end with a nut 152; the upper housing 13 of the shock absorber is provided with a guide rod limiting hole 132, and the upper bearing plate 14 of the shock absorber is also provided with an upper bearing plate guide rod mounting hole 142. The diameter of the upper bearing plate guide rod mounting hole 142 is slightly larger than the diameter of the vertical guide rod 15 and the same as the diameter of the guide rod limiting hole 132; the threaded end of the vertical guide rod 15 passes through the guide rod mounting hole 142 and the guide rod limiting hole 132 into the shock absorber constraint housing 12.

[0091] Furthermore, the vibration damper 1 also includes a vibration damping housing 16, a transmission guide rod 17, and a vibration damper intermediate plate 18; the vibration damping housing 16 includes a vibration damping housing constraint unit 163 disposed on the vibration damping constraint housing 12, a vibration damping valve 161 slidably disposed in the vibration damping housing constraint unit 163, a preload spring 162 disposed on one side of the vibration damping valve 161, the preload spring 162 abutting against the inner wall of the vibration damping housing constraint unit 163, and a vibration damping valve limiting groove 1611 machined on the other side of the vibration damping valve 161; the vibration damper intermediate plate 18 is located at In the shock absorber constraint housing 12, a middle plate through hole 181 is opened in the middle for the bearing spring 19 to pass through. The middle plate 18 of the shock absorber is provided with a middle plate threaded hole 183. The lower end of the vertical guide rod 15 is connected to the middle plate threaded hole 183 of the middle plate of the shock absorber 18. The side of the middle plate 18 of the shock absorber is cut with a smooth arc-shaped middle plate limiting groove 184. The end of the transmission guide rod 17 is a cylindrical head, one end of which is located in the middle plate limiting groove 184, and the other end of which is embedded in the damping valve limiting groove 1611.

[0092] The vibration damping box constraint unit 163 has an open tank structure. The inner wall of the vibration damping box constraint unit 163 is provided with a first preload spring limiting groove 1631, and the vibration damping valve 161 is provided with a second preload spring limiting groove 1612. One end of the preload spring 162 is engaged in the first preload spring limiting groove 1631, and the other end is engaged in the second preload spring limiting groove 1612.

[0093] The upper support bracket 3 of the caster is provided with an upper support elongated hole 31, and the lower support bracket 6 of the caster is provided with a lower support elongated hole 62. The upper support bracket 3 and the lower support bracket 6 of the caster are slidably connected through the upper support elongated hole 31 and the lower support elongated hole 62.

[0094] The installation process for shock absorber 1 is as follows:

[0095] The first step is to weld the damping housing 16 to the inner wall of the damper constraint housing 12 in pairs, ensuring that the damping housing 16 are symmetrically arranged inside the damper constraint housing 12. If the inner cavity of the damper constraint housing 12 is too small and welding is inconvenient, a metal adhesive with sufficient curing strength can be used to connect the damping housing 16 to the inner wall of the damper constraint housing 12.

[0096] The second step is to use the vertical guide rod 15 to pass through the upper bearing plate guide rod mounting hole 142 on the upper bearing plate 14 of the shock absorber and the guide rod limiting hole 132 on the upper housing 13 of the shock absorber in sequence, and tighten it into the middle plate threaded hole 183 of the middle plate 18 of the shock absorber, so that the upper bearing plate 14, the upper housing 13 and the middle plate 18 of the shock absorber are connected together by the vertical guide rod 15.

[0097] The third step is to pass the load spring 19 through the intermediate plate through hole 181 of the shock absorber intermediate plate 18 and the shock absorber upper housing through hole 131 of the shock absorber upper housing 13, and insert one end of it into the upper fixing buckle 141 of the load spring; then, by welding or using a metal adhesive with sufficient solidification strength, the top contact surface of the load spring 19 with the upper fixing buckle 141 of the load spring is joined together.

[0098] Fourth step, adjust the positions of the upper bearing plate 14, the upper housing 13, and the middle plate 18 of the shock absorber to ensure that the upper housing 13 is connected to the upper end of the opening of the shock absorber constraint housing 12, and that the middle plate 18 is placed inside the cavity of the shock absorber constraint housing 12; then weld or use metal adhesive to connect the upper housing 13 and the shock absorber constraint housing 12 together.

[0099] Fifth step, insert the transmission guide rod 17 from the lower end of the damper constraint housing 12, so that one end of the transmission guide rod 17 is embedded in the intermediate plate limiting groove 184 and the other end is embedded in the damping valve limiting groove 1611.

[0100] Step 6: Place the lower housing 11 of the shock absorber at the lower end of the shock absorber constraint housing 12, ensuring that the load-bearing spring 19 can be embedded in the lower fixing buckle 112 of the load-bearing spring; apply metal adhesive to the inner wall of the lower fixing buckle 112 of the load-bearing spring in advance, so that the surface of the load-bearing spring 19 in contact with the bottom of the lower fixing buckle 112 of the load-bearing spring is tightly bonded together; at this point, the assembly of the shock absorber 1 is completed.

[0101] The installation process for lightweight fixed industrial casters is as follows:

[0102] First, place the wheel 4 inside the lower caster bracket 6, and connect the wheel 4 to the lower caster bracket 6 using bearing rollers 5, ensuring that the wheel 4 can rotate freely on the bearing rollers 5. Next, use mounting bolts 7 to pass through the mounting holes 111 on the lower housing of the shock absorber and the pre-drilled threaded holes on the lower caster bracket 6 to securely connect the shock absorber 1 to the lower caster bracket 6. Then, install the upper caster bracket 3 onto the lower caster bracket 6, ensuring that the upper bracket boss 32 presses against the upper bearing plate 14 of the shock absorber. Finally, weld the upper caster plate 2 to the upper caster bracket 3. At this point, the installation of the lightweight fixed industrial caster is complete.

[0103] During caster operation: Because the upper support 3 and lower support 6 are connected by an elongated hole 31 in the upper support and an elongated hole 62 in the lower support, the main load-bearing point of the directional industrial caster is concentrated on the two shock absorbers 1 under the weight of the mobile welding platform 8. Therefore, when the wheel 4 rolls on uneven ground, the lower support 6 and shock absorbers 1 of the directional industrial caster will move up and down with the bumps in the ground. However, due to the elongated hole and the shock absorbers 1 between the upper support 3 and the lower support 6, the vibration is isolated at the lower support, thus ensuring that the mobile welding platform supported by the caster does not vibrate up and down with the undulations of the ground.

[0104] Example 2: This invention also discloses a method for calculating the performance curve of directional industrial casters for mobile welding platforms, applied to directional industrial casters for mobile welding platforms. The directional industrial casters for mobile welding platforms have shock absorbers 1 arranged symmetrically in groups inside. After the casters are assembled, the upper caster plate 2 is used to connect the heavy object (welding platform 8). At this time, the gravity transmission path of the mobile welding platform 8 is: upper caster plate 2, upper caster bracket 3, shock absorber 1, lower caster bracket 6, bearing roller 5, and wheel 4. Therefore, the shock absorber 1 must be designed reasonably to ensure that the force is not directly transmitted from the upper caster bracket 3 to the lower caster bracket 6, but is buffered and transmitted through the shock absorber 1.

[0105] In the initial state, the upper bearing plate 14 of the shock absorber 1 is at its farthest position from the upper housing 13 of the shock absorber. When the gravity of the moving welding platform 8 is applied, both the bearing spring 19 and the preload spring 162 will be compressed. In the design, it is necessary to ensure that when the gravity of the moving welding platform 8, the restoring force of the preload spring 162, and the restoring force of the bearing spring 19 reach force balance in the vertical direction, the transmission guide rod 17 must remain parallel to the horizontal plane, corresponding to point P in the figure.

[0106] When rolling on uneven surfaces, wheel 4 will experience up-and-down vibrations. This vibration will travel along wheel 4-bearing roller 5-caster lower bracket 6-vibration damper 1. At this time, the middle plate 18 of the vibration damper will move up or down at the point where the gravity of the moving welding platform 8, the restoring force of the preload spring 162, and the restoring force of the load-bearing spring 19 are balanced. During this stage, the output force of the vibration damper 1 in the diagram changes from point P to point P. 01 Point (X) 01 ,Y 01 ) and P 02 Point (X) 02 ,Y 02 The sound echoes repeatedly between the points.

[0107] from Figure 7 It can be seen from P 01 Point (X) 01 ,Y 01 ) and P02 Point (X) 02 ,Y 02 Between points 1 and 2, the slope of the force-displacement curve of the shock absorber 1 is close to zero, meaning that the stiffness of the shock absorber 1 is close to zero. Therefore, the force transmission path of the vibration is interrupted, and the vibration will not be transmitted from the shock absorber 1 to the caster bracket 3, thus achieving effective isolation of the vibration generated when the caster moves on the ground.

[0108] Therefore, the essence of caster design is to make the vertical output force at the point near zero stiffness in the performance range of the shock absorber in the caster equal to the weight of the mobile welding platform that needs to be supported. Therefore, the calculation of the performance curve of the shock absorber is crucial.

[0109] for Figure 37 The caster shock absorber 1 shown, without considering the effect of the load-bearing spring 19, when the shock absorber 1 is subjected to an external force, its upper load-bearing plate 14 will move downward, which will cause the preload spring 162 and the load-bearing spring 19 to be compressed. At this time, there are three forces in the vertical direction of the shock absorber 1: the vertical component of the restoring force of the preload spring 162, the restoring force of the load-bearing spring 19, and the external force F.

[0110] The performance curve of the shock absorber can be obtained as follows:

[0111] Therefore, to solve for the restoring force curve of the shock absorber, we need to:

[0112] S1: First, we need to establish the virtual work principle equation for damper 1. Since the restoring forces of the load-bearing spring 19 and the preload spring 162 satisfy linear addition, we first exclude the restoring force of the load-bearing spring 19 and only consider the effect of the preload spring:

[0113] Fx-2F h tan(β)δx=F Y δx-2F h tan(β)δx=0 (1);

[0114] In the formula, x represents the vertical displacement of the bearing plate 14 on the damper 1 relative to its equilibrium position; F h β is the horizontal spring force of the preloaded spring 162; β is the angle between the transmission guide rod 17 and the horizontal line; F Y F is to eliminate the restoring force of the external damper 1 of the bearing spring 19; F is to eliminate the external force of the external damper 1 of the bearing spring 19.

[0115] S2: Determine the restoring force of a single preloaded spring 162:

[0116] F h =K h (L0-L ry (2);

[0117] In the formula, L ry L0 represents the actual length of the preload spring 162 at any working position during the working stroke of the damper; L0 represents the original length of the preload spring 162; K h The preloaded spring has a stiffness of 162.

[0118] S3: Calculate the angle between the transmission guide rod and the horizontal line:

[0119] tan(β)=(h sjj -x)(bL ry ) -1 (3);

[0120] In the formula, h sjj 1 is the vertical distance from the reference plane of the upper bearing plate 14 of the damper 1 to the geometric center line of the preload spring 162; b is the shortest horizontal distance between the inner wall of the damper constraint housing 12 and the side surface of the damper intermediate plate 18 near the preload spring 162.

[0121] S4: Calculate the vertical distance from the reference plane of the upper bearing plate 14 of the damper 1 to the geometric center line of the preload spring 162:

[0122]

[0123] In the formula, 'a' represents the length of the transmission guide rod.

[0124] S5: Calculate the actual length of the preloaded spring at any working position during the working stroke of the shock absorber:

[0125]

[0126] S6: Substitute equations (2)-(5) into equation (1) to obtain the overall restoring force equation of the damper (excluding the effect of the bearing spring 19);

[0127]

[0128] S7: Differentiate x in the overall restoring force equation of damper 1 to obtain the stiffness curve equation of damper 1;

[0129] make:

[0130] δ1=b-L0 (7);

[0131] δ2=a 2 -δ1 2 (8);

[0132]

[0133] Equation (6) can be simplified to:

[0134]

[0135] Differentiating x, we obtain the stiffness curve equation for damper 1:

[0136]

[0137] S8: Integrating the load-bearing spring 19 yields the overall restoring force equation F for a single shock absorber 1. JZ and stiffness displacement equation K JZ

[0138]

[0139] In the formula: K CZ To provide the stiffness for bearing spring 19.

[0140] If a single caster has a set of two shock absorbers, and it is required that the shock absorber can withstand an external force M when the load plate on the shock absorber drops to x0, then the size of the shock absorber and the spring parameters satisfy the following formula (14):

[0141]

[0142] The directional industrial casters for mobile welding platforms and the method for calculating their performance curves provided in this application effectively overcome the technical bottlenecks of traditional industrial casters in terms of high load-bearing capacity, excellent vibration reduction, and directional stability through collaborative design of structural innovation and theoretical modeling. The specific beneficial effects are as follows:

[0143] 1. Multi-stage vibration reduction system achieves synergistic optimization of load bearing and vibration reduction.

[0144] The multi-stage vibration reduction structure, consisting of a preload spring, a load-bearing spring, and a vibration damping valve, provides initial preload to balance static loads. The load-bearing springs bear the main dynamic loads, and the vibration damping valves convert vertical vibrations into horizontal spring forces through transmission guide rods. This achieves graded buffering of vibration energy and solves the industry problem of "high loads inevitably require sacrificing vibration reduction."

[0145] 2. Rigid constraints and sliding connections ensure orientation accuracy.

[0146] The upper and lower brackets of the caster are slidably connected through an elongated hole, and with the limiting design of the vertical guide rod of the shock absorber, a strict directional constraint mechanism is formed. Compared with swivel casters, this structure effectively avoids the lateral displacement of the welding path caused by vibration, and significantly reduces defects such as incomplete penetration and undercut.

[0147] 3. Performance curve calculation methods support precise design.

[0148] By establishing the virtual work principle equation and the mathematical model of restoring force and stiffness, the force-displacement curves and stiffness characteristic equations of the vibration damper throughout its entire stroke are derived, achieving a precise mapping from theoretical parameters to actual performance. This method can reverse-optimize key parameters such as spring stiffness and guide rod length based on working conditions such as welding platform load and ground roughness, thus shortening the product development cycle.

[0149] 4. Modular structure enhances industrial applicability

[0150] The shock absorber and caster bracket adopt a modular design with bolted connection, which facilitates later maintenance and component replacement; significantly expanding the application range of industrial casters.

[0151] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of the invention. All equivalent changes made based on the description and drawings of the present invention are included within the scope of the present invention.

Claims

1. A type of directional industrial caster for a mobile welding platform, characterized in that, include: Caster top plate, used to support the welding platform; The caster upper bracket is located under the caster upper plate, and the caster upper bracket is provided with an upper bracket boss; The lower support of the caster is slidably connected to the upper support of the caster, and the lower support of the caster is provided with bearing rolling holes; The round wheel is placed inside the lower bracket of the caster and connected to the lower bracket of the caster through a bearing roller; The shock absorber is connected to the lower bracket of the caster by mounting bolts, and the upper end of the shock absorber is tightly pressed against the bracket boss.

2. The directional industrial caster for a mobile welding platform according to claim 1, characterized in that: The vibration damper includes a lower housing, a constraint housing, and an upper housing. A load-bearing spring is mounted on the lower housing. An upper load-bearing plate is also mounted on the upper side of the upper housing. A through-hole corresponding to the load-bearing spring is provided on the upper housing, through which the load-bearing spring passes and connects to the upper load-bearing plate. A vertical guide rod is also provided on the upper load-bearing plate. A guide rod limiting hole is provided on the upper housing, through which the vertical guide rod passes.

3. The directional industrial caster for the mobile welding platform according to claim 2, characterized in that: The vibration damper also includes a vibration damping housing, a transmission guide rod, and a vibration damper intermediate plate. The vibration damping housing includes a vibration damping housing constraint unit mounted on the vibration damping housing. A vibration damping valve is slidably mounted in the vibration damping housing constraint unit. A preload spring is mounted on one side of the vibration damping valve and abuts against the inner wall of the vibration damping housing constraint unit. A vibration damping valve limiting groove is machined on the other side of the vibration damping valve. The vibration damper intermediate plate is located in the vibration damping housing constraint unit. A through hole for a load-bearing spring is opened in the middle of the intermediate plate. The lower end of the vertical guide rod is connected to the vibration damper intermediate plate. A limiting groove is cut on the side of the vibration damper intermediate plate. The end of the transmission guide rod is a cylindrical head, with one end located in the limiting groove of the intermediate plate and the other end embedded in the limiting groove of the vibration damping valve.

4. The directional industrial caster for a mobile welding platform according to claim 3, characterized in that: The inner wall of the vibration damping box constraint unit is provided with a first preload spring limiting groove, and the vibration damping valve is provided with a second preload spring limiting groove. One end of the preload spring is engaged in the first preload spring limiting groove, and the other end is engaged in the second preload spring limiting groove.

5. The directional industrial caster for a mobile welding platform according to claim 2, characterized in that: The lower housing of the shock absorber is provided with a lower fixing buckle for the bearing spring in the middle position, and the bottom of the upper bearing plate of the shock absorber is provided with an upper fixing buckle for the bearing spring. The upper end of the bearing spring is locked in the upper fixing buckle for the bearing spring, and the lower end is locked in the lower fixing buckle for the bearing spring.

6. The directional industrial caster for a mobile welding platform according to claim 1, characterized in that: The caster top plate is a rectangular connecting plate with caster mounting holes. The caster top plate is connected to the welding platform through the caster mounting holes.

7. The directional industrial caster for a mobile welding platform according to claim 1, characterized in that: The upper bracket of the caster is provided with an upper bracket elongated hole, and the lower bracket of the caster is provided with a lower bracket elongated hole. The upper bracket and the lower bracket of the caster are slidably connected through the upper bracket elongated hole and the lower bracket elongated hole.

8. A method for calculating the performance curve of directional industrial casters for mobile welding platforms, characterized in that, The application of the mobile welding platform according to any one of claims 1 to 7 using directional industrial casters comprises the following steps: S1: Establish the equation for the virtual work principle of the vibration damper: Fx-2F h tan(β)δx=F Y δx-2F h tan(β)δx=0 (1); In the formula, x represents the vertical displacement of the bearing plate on the damper relative to its equilibrium position; F h β is the horizontal spring force of the preloaded spring; β is the angle between the transmission guide rod and the horizontal line; F Y F represents the force required to eliminate the restoring force of the load-bearing spring external damper; F represents the external force required to eliminate the load-bearing spring external damper. S2: Determine the restoring force of the preloaded spring: F h =K h (L0-L ry ) (2); In the formula, L ry L0 is the actual length of the preload spring at any working position during the working stroke of the shock absorber; K is the original length of the preload spring. h This refers to the preload spring stiffness; S3: Calculate the angle between the transmission guide rod and the horizontal line: tan(β)=(h sjj -x)(bL ry ) -1 (3); In the formula, h sjj 1 is the vertical distance from the reference plane of the upper bearing plate of the shock absorber to the geometric center line of the preload spring; b is the shortest horizontal distance between the inner wall of the shock absorber constraint housing and the side surface of the shock absorber intermediate plate near the preload spring. S4: Calculate the perpendicular distance from the reference plane of the upper bearing plate of the shock absorber to the geometric center line of the preload spring: In the formula, 'a' is the length of the transmission guide rod; S5: Calculate the actual length of the preloaded spring at any working position during the working stroke of the shock absorber: S6: Substitute equations (2)-(5) into equation (1) to obtain the overall restoring force equation of the damper; S7: Differentiate x in the overall restoring force equation of the damper to obtain the stiffness curve equation of the damper; S8: Integrating the load-bearing springs yields the overall restoring force equation and stiffness-displacement equation for a single vibration damper.

9. The method for calculating the performance curve of directional industrial casters for mobile welding platforms according to claim 1, characterized in that: Step S7 specifically includes: make: δ1=b-L0 (7); δ2=a 2 -d1 2 (8); Equation (6) can be simplified to: Differentiating x, we obtain the stiffness curve equation of the vibration damper:

10. The method for calculating the performance curve of directional industrial casters for mobile welding platforms according to claim 9, characterized in that: S8: Integrating the load-bearing springs yields the overall restoring force equation F for a single shock absorber. JZ and stiffness displacement equation K JZ Where: K CZ This is to support the stiffness of the spring.

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