WO2012079538A1

WO2012079538A1 - All-direction wheel

Info

Publication number: WO2012079538A1
Application number: PCT/CN2011/084150
Authority: WO
Inventors: 张豫南; 李瀚飞
Original assignee: 浙江美科斯叉车有限公司
Priority date: 2010-12-17
Filing date: 2011-12-16
Publication date: 2012-06-21

Abstract

Disclosed is an all-direction wheel comprising a hub (1), roller supporting brackets (2) and rollers (3), with roller supporting brackets (2) arranged on the hub (1), roller shafts (4) arranged in the rollers (3), and both ends of the roller shafts (4) being fitted on the roller supporting brackets (2); the roller supporting brackets (2) are uniformly distributed along the outer circumference of the hub (1) with a central supporting method being adopted to mount the roller supporting brackets (2) onto the hub (1), and the rollers (3) are mounted on the roller supporting brackets (2) via the roller shafts (4) by adopting a method of support at both ends, with an included angle of 45° between the axis (300) of each of the rollers (3) and the axis (100) of the hub (1). The outer border (333) of each of the rollers (3) is an involute curved surface, and there are eight roller supporting brackets (2) mounted on the hub (1); when defining the plane perpendicular to the axis (100) of the hub as a projecting plane, the outer profile of the orthogonal projection in the defined projecting plane from the outer profile of the eight rollers (3) on the eight roller supporting brackets (2) is a complete circle (334). The "involute" of the roller surface is a special curve gradually spreading out on the roller, it forms a circular outer edge of the all-direction wheel, and the accurate calculation thereof enables the all-direction wheel to operate more smoothly and more efficiently.

Description

Omnidirectional wheel

技术领域 Technical field

The invention relates to an omnidirectional wheel.

背景技术Background technique

The omnidirectional drive is a drive that can be moved directly in any direction. The omnidirectional wheel is a mechanism that evenly distributes a plurality of rollers around a hub. The hub is powered by a power transmission, and the roller is mounted on the hub. The end face is free to rotate, and the omnidirectional wheel is the basis for achieving all-round walking.

At present, most of the omnidirectional wheels are light-load, low-power experimental products, which are mainly used in the research of the motion mechanism of small robots. The structure is generally fixed by the end of the roller, and the contour of the roller on the side of the hub is only close to the circle. Therefore, it is easy to generate periodic jump on the hub axle, causing periodic impact on the roller, losing a lot of driving power, reducing the driving payload, and increasing the difficulty of driving.

发明内容 Summary of the invention

The present invention is directed to a deficiencies in the prior art and provides an omnidirectional wheel.

In order to solve the above technical problems, the present invention is solved by the following technical solutions:

The omnidirectional wheel comprises a wheel hub, a roller support frame and a roller wheel. The wheel hub is provided with a roller support frame, and the roller wheel is provided with a roller axle, and both ends of the roller axle are mounted on the roller support frame. The roller support frame is evenly distributed at the outer circumference of the hub, and the roller support frame is mounted on the hub by means of an intermediate support manner, and the roller is mounted on the roller support frame by the support of both ends through the roller axle.

Preferably, the roller axis of the roller and the hub axis of the hub are at an angle of 45°, and the outer edge of the roller is an involute curved surface.

Preferably, eight roller support frames are mounted on the hub, the plane perpendicular to the hub axis is defined as the projection surface, and the outer contours of the eight rollers on the eight roller support frames are positive on the defined projection surface. The outer contour of the projection is a full circle. Based on the load capacity of the platform and the installation dimensions of the omnidirectional wheel, the bearing size is selected as the constraint, and the knowledge of the Mecanum wheel is used to determine the size of the roller shaft and the contour of the roller. Processed in the center. In order to facilitate the processing, by calculation, a circle is used, and its diameter is basically matched with the side projection on the omnidirectional wheel after being rotated by 45 degrees, that is, the projection is circular, and this design method changes the requirements of the omnidirectional wheel principle. The speed of the spiral method greatly improves the processing technology and ensures the machining accuracy. The 'involute line' on the surface of the roller is a special curve that gradually spreads on the roller. It forms the outer edge of the omnidirectional wheel. This outer edge is a circle. Its accurate calculation is the key to smooth walking on the omnidirectional platform.

Of the several design methods, some replaced the contour of the roller with a circular arc of the circumference, or a circular arc connection of several different diameters. The generated roller is calculated by the above method, and the three-dimensional modeling is performed. The axial projection of the obtained omnidirectional wheel is not the theoretical circumference, and the end of the roller has obvious 'bumps', which causes the bump of the wheel during the movement. The omni-directional mobile platform is difficult to apply in engineering.

From the axial projection of the hub, the outer edge of the omnidirectional wheel should be a circle, ie the outer surface of the roller of the omnidirectional wheel must envelop to form a complete circle with a radius equal to the radius of the wheel. Based on this, a comprehensive design approach was proposed:

1. Determine the radius of the wheel and the radius of the end of the roller according to the actual load-bearing, use and installation requirements;

2. Then calculate the number of rollers according to the principle of non-interference;

3. Taking into account the bearing capacity and the degree of coincidence of the roller, the axial length of the roller is calculated;

4. Finally, according to the projection as the theoretical circumference, the radius of the middle end of the roller is designed, and the nonlinear involute of the circle is calculated.

When selecting the number of rollers, it is necessary to balance the continuity of the motion with no motion interference, and select the number of rollers. If the wheel motion continuity ratio coefficient, the contour of the roller can be obtained through the program, and the overall diagram of the wheel can be obtained in the three-dimensional software. At this point, you can observe whether the roller interferes. If some conditions are not met, it needs to be changed until both conditions meet the requirements. The basic parameters of the designed omnidirectional wheel are shown in Table 1.

R(mm) R(mm)	NN	ε ε	l(mm) l(mm)	α α
230 230	8 8	1.088 1.088	260.78 260.78	45 ° 45 °

Table 1 Basic geometric parameters of the omnidirectional wheel

Preferably, the wheel hub is provided with eight roller support frames, the surface perpendicular to the hub axis is defined as a projection surface, and the outer contours of the eight rollers on the eight roller support frames are defined on the projection surface. The outer contour of the upper orthographic projection is a full circle. All roller projections form a circle whose contour diameter is consistent with the diameter of the wheel, ensuring that the pressure applied at any point on the contour circle points to the center of the hub. The pressure on the roller is transmitted to the roller support through the roller shaft and then to the hub axle.

Preferably, the outer circumference of the hub is uniformly provided with eight mounting chutes, and the direction of the mounting chute is at an angle of 45° with the hub axis of the hub. Eight mounting chutes are evenly distributed on the outer circumference of the hub, and mounting holes are formed in each mounting chute for mounting the roller support frame, and the angle between the mounting chute and the hub axle is 45 degrees, so that the omnidirectional wheel is arbitrary When the angle is rotated, the force is uniform. The inside of the hub has a positioning hole that is mounted close to the motor reducer and fastened by bolting. The inside of the hub is the mounting surface and the outside has reinforcing ribs to increase the strength and toughness of the hub while reducing the weight of the hub. The intersection of the axis of the cantilever roller axle mounting hole and the section in the hub is evenly distributed over one circumference.

Preferably, two support arms are vertically disposed on two sides of the bottom plate of the roller support frame, the support arm is provided with a shaft hole, a bottom groove is arranged below the bottom plate, and rib plates are arranged on both sides of the bottom groove, and the installation chute is arranged The bottom groove cooperates with each other and is fixed to each other, and the roller support frame is fixed on the installation chute. The bottom plate of the roller support frame has an arc shape.

Preferably, the outer diameter of the middle portion of the roller is larger than the outer diameter of the two ends, and the roller includes a roller outer casing and a roller main body, and the inside of the roller main body is a cavity. The cavity structure not only saves material, but also improves the smoothness of the wheel running and reduces the load. The middle diameter of the roller is larger than the diameter of both ends and is olive-shaped. Each roller axle is at an angle of 45° to the hub axle, and all rollers are projected on the side of the omnidirectional wheel to form a full circle.

Preferably, the inner and outer surfaces of the roller outer casing are integrally formed by open molding, and the thickness of the roller outer casing is uniform, and the material thereof is a cast polyurethane elastomer, and the material has high wear resistance.

Preferably, the roller axle frame is on the roller support frame, and the outer end is provided with a locking piece, and the locking piece is fixed by a nut. The shape of the locking piece is matched with the shape of the bolt head at the shaft end, and the locking piece is fixed to the supporting arm by a nut.

According to the technical solution of the present invention, the omnidirectional wheel can run more smoothly and efficiently, and can be used on a large-scale all-round mobile forklift.

附图说明 DRAWINGS

Fig. 1 is a front view of the omnidirectional wheel of the present invention.

Figure 2 is a left side view of Figure 1.

Figure 3 is a perspective view of the hub of the present invention.

Figure 4 is a cross-sectional view of the roller support frame of the present invention.

Figure 5 is a perspective view of the roller support frame of the present invention.

Figure 6 is a bottom perspective view of the roller support frame of the present invention.

Figure 7 is a cross-sectional view showing the mounting of the roller of the present invention.

Figure 8 is a cross-sectional view of the roller of the present invention.

Figure 9 is a cross-sectional view of the roller shaft of the present invention.

Figure 10 is a right side elevational view of the roller shaft of the present invention.

具体实施方式 detailed description

Referring to Figures 1 and 2, the omnidirectional wheel includes a hub 1 and a roller 3, and the outer circumference of the hub 1 is uniformly provided with eight mounting chutes 11, the direction of which the chute 11 is mounted and the hub axis 100 of the hub 1 is 45° Angle. The mounting chute 11 is provided with eight roller support frames 2 defining a plane perpendicular to the hub axis 100 as a projection surface, and the outer contours of the eight rollers 3 on the eight roller support frames 2 are defined in the projection The outer contour of the orthographic projection on the surface is a full circle 334. The roller support frame 2 is mounted on the hub 1 in an intermediate support manner, and the roller 3 is mounted on the roller support frame 2 by means of both ends of the roller shaft 4, the roller axis 300 of the roller 3 and the hub axis of the hub 1 100 is at an angle of 45°, and the outer edge 333 of the roller 3 is an involute curved surface.

Referring to FIG. 3, the inclined bottom surface 110 of the mounting chute 11 is provided with at least one mounting hole 111. The mounting chute 11 is also provided with at least one mounting hole 12 corresponding to the side of the hub 1, the direction of the mounting chute 11 and the hub 1 The hub axis 100 forms an angle of 45°, so that the omnidirectional wheel can easily change direction and achieve multi-directional motion. The inside of the hub 1 has a positioning hole which is closely mounted to the motor reducer and fastened by bolting. The inner side of the hub 1 is a mounting surface and has a reinforcing rib on the outer side to increase the strength and toughness of the hub while reducing the weight of the hub. The intersection of the roller support frame 2 and the cross section in the hub is evenly distributed over one circumference.

Referring to Figures 4, 5 and 6, the roller support 2 is coupled to the mounting chute 11 by a recess 24 and a screw and hub 1. The bottom plate 21 of the roller support frame 2 has an arc shape and cooperates with the shape of the roller 3. The two sides of the bottom plate 21 are vertically provided with two support arms 22, and the support arm 22 is provided with a shaft hole 23, a shaft hole 23 and a roller. The shaft is matched and installed, and a bottom groove 25 is disposed under the bottom plate 21. The bottom groove 25 and the mounting groove 11 are in the same direction, and the ribs 26 are disposed on both sides of the bottom groove 25. The bottom groove 25 of the bottom plate 21 is fitted to the mounting chute 11 of the roller body 1. At the time of installation, the bottom groove 25 and the mounting chute 11 are fitted, the mounting hole 252 of the bottom groove side surface 251 and the mounting hole 12 on the side of the hub 1 are cooperatively connected, the mounting hole 254 of the bottom groove top surface 253 and the mounting chute bottom surface 110 The mounting holes 111 are coupled to each other such that the roller support frame 2 is fixed to the roller body 1. The inner surface 241 of the roller support frame 2 is provided with a recess 24 corresponding to the portion of the bottom groove 25. The depth of the groove 24 coincides with the height of the exposed head of the screw, so that after the screw is fastened on the mounting hole 254, the rotation of the roller is not affected by the height of the screw head, and the rotation of the roller is interfered.

Referring to Figures 7, 8, 9 and 10, the outer edge of the roller 3 employs an involute curved track. The roller 3 is a unitary body having a diameter larger than the diameter of both sides, and the roller 3 includes a roller body 32 and a roller casing 31. The outer contour of the roller body 32 is uniformly reduced in size by the roller outer casing 31, and the tightness with the roller outer casing 31 is increased. The thickness of each part of the roller outer casing 31 is uniform, and the outer layer of the roller main body 32 is a roller outer casing 31. The inner and outer surfaces of the roller outer casing 31 are completed by mold opening, and the material thereof is a cast polyurethane elastic body, and may also be made of rubber. The inside of the roller body 32 is provided with a cavity 33, and the arrangement of the cavity 33 saves the material and increases the elasticity of the roller. A bearing cavity 34 is symmetrically disposed at both ends of the roller body 32, and an inner boss 321 is disposed in the bearing cavity 34, and a shaft hole 322 is disposed in the inner boss 321 . The bearing chambers 34 at both ends have a bearing 5 built therein, and the roller shaft 4 passes through the bearing 5 and the shaft hole 322 of the inner boss 321 to support the roller. One end of the roller shaft 4 for supporting the roller is provided with a boss 41. The boss 41 includes a first boss 401 and a second boss 402, and the other end is provided with a countersunk threaded hole 42. The first boss 401 on the roller shaft 4 is cooperatively positioned with the roller support frame 2, and the second boss 402 is cooperatively positioned with the bearing 5. The other end Countersunk head The threaded hole 42 and the screw 6 cooperate to fix the locking piece 7. The middle of the locking piece 7 is provided with a screw hole. The screw hole 71 is provided corresponding to the size of the screw hole. The locking piece 7 is further provided with at least two small screw holes. The inner surface of the locking piece 7 is further provided with a protruding inner ring 72. The roller shaft 4 is supported on the roller support frame 2, and the roller shaft 4 end provided with the countersunk threaded hole 42 is engaged with the inner ring 72, and the inner ring 72 is in contact with the roller support frame 2, and the locking piece 7 is fixed by the screw 6. It is fixed to the roller support frame 2 while fixing the roller shaft 4. The screw hole catches the screw 6, prevents the screw 6 from rotating and loosening, and is fixed and fastened by the small screw 61 to ensure the safe use of the roller shaft 4, and fixes the roller shaft 4 to prevent the roller shaft 4 from loosening and causing the roller 3 to fall off. accident. The thickness of the roller body 32 is uniform and uniform, and the stress applied to the roller 3 is uniform when the force is applied, and the stress is not caused by the uneven force, and the roller 3 is rolled and beats due to the imbalance, resulting in full use. The equipment of the azimuth wheel is shaking.

The contour profile of the roller 3 and the size of the roller shaft 4 are based on the load capacity of the platform and the installation dimensions of the omnidirectional wheel. The installation dimensions of the selected bearing are used as constraints, and the knowledge of the Mecanum wheel is used to determine and be in the machine. The machining drawing software uses a number of arcs to approximate the constant velocity spiral and is machined in the CNC machining center. In order to facilitate the processing, by calculation, a circle is used, and its diameter is basically matched with the side projection on the omnidirectional wheel after being rotated by 45 degrees, that is, the projection is circular, and this design method changes the requirements of the omnidirectional wheel principle. The speed of the spiral method greatly improves the processing technology and ensures the machining accuracy.

Claims

The omnidirectional wheel comprises a hub (1), a roller support frame (2) and a roller (3), and the wheel hub (1) is provided with a roller support frame (2), characterized in that: the roller (3) is provided There is a roller axle (4), and both ends of the roller axle (4) are mounted on the roller support frame (2).
The omnidirectional wheel according to claim 1, characterized in that the roller axis (300) of the roller (3) and the hub axis (100) of the hub (1) are at an angle of 45°, the roller ( The outer edge (333) of 3) is an involute surface.
The omnidirectional wheel according to claim 2, wherein said wheel hub (1) is provided with eight roller support frames (2), and a surface perpendicular to the hub axis (100) is defined as a projection surface. The outer contour of the eight projections (3) on the eight roller support frames (2) on the defined projection surface is a full circle (334).
The omnidirectional wheel according to claim 2, characterized in that: the outer circumference of the hub (1) is uniformly provided with eight mounting chutes (11), the direction of the mounting chute (11) and the hub (1) The hub axis (100) is at an angle of 45°.
The omnidirectional wheel according to claim 4, characterized in that: two support arms (22) are arranged on both sides of the bottom plate (21) of the roller support frame (2), and a shaft hole is arranged on the support arm (22) (23) The bottom plate (21) is provided with a bottom groove (25), and the bottom groove (25) is provided with ribs (26) on both sides thereof, and the installation chute (11) and the bottom groove (25) cooperate with each other and are fixed to each other. The wheel support frame (2) is fixed to the mounting chute (11).
The omnidirectional wheel according to claim 1, wherein an outer diameter of a middle portion of said roller (3) is larger than an outer diameter of both ends, and said roller (3) includes a roller outer casing (31) and a roller main body. (32) The inside of the roller body (32) is a cavity (33).
The omnidirectional wheel according to claim 6, characterized in that the roller outer casing (31) is integrally formed by open molding, and the roller outer casing (31) has the same thickness and is made of a cast polyurethane elastomer.
The omnidirectional wheel according to claim 1, characterized in that the roller shaft (4) is mounted on the roller support frame (2), the outer end is provided with a locking piece (7), and the locking piece (7) is provided by a screw. (6) Fixed.