Speed control system, hub motor and agricultural unmanned vehicle

Abstract

The invention discloses a speed control system, a hub motor and an agricultural unmanned vehicle, and belongs to the technical field of transmission equipment. The speed change system adopts the spherical roller as a transmission body of the input and output structure, and is provided with the centrifugal part which does centrifugal motion along with the actual rotating speed of the output structure, and the self-adaptive adjustment of the transmission ratio and the stepless speed change are realized along with the change of the position of the centrifugal part and the change of the inclination angle of the first axis of the spherical roller. According to the hub motor and the agricultural unmanned vehicle, the centrifugal mechanism can be matched with the spherical roller capable of doing precession motion, the transmission ratio can be adjusted in a self-adaptive and stepless mode, the output characteristic of the motor with the fixed transmission ratio can be achieved through the motor with the smaller power, cost is reduced, and self-adaptive speed regulation can be achieved in various scenes.

Description

Technical Field

[0001] The present invention relates to the technical field of transmission equipment, and in particular to a speed change system, a hub motor and an agricultural unmanned vehicle. Background Art

[0002] In the related technology, many motors have fixed transmission ratios, such as many wheel hub motors have fixed transmission ratios. It is impossible to change the transmission ratio according to the working conditions to achieve low-speed high-torque or high-speed low-torque working conditions when a single motor is driven. The only way to meet higher working requirements is to increase the motor output power. This means that in vehicles using wheel hub motors or other equipment using fixed transmission ratio motors, the selected motors need to be upwardly compatible with less common extreme working conditions, resulting in the need to use higher power motors. However, when high-power motors are used, the value of high power is only reflected in a few situations, which reduces the cost-effectiveness of the entire equipment. Summary of the invention

[0003] One of the purposes of the embodiments of the present invention is to provide a speed change system, which can adaptively adjust the transmission ratio according to the actual rotation speed of the output structure through the cooperation of the centrifugal mechanism and the spherical roller.

[0004] A second objective of the embodiment of the present invention is to provide a hub motor that can adaptively adjust the transmission ratio according to the actual rotation speed of the motor.

[0005] The third purpose of the embodiment of the present invention is to provide an agricultural unmanned vehicle that can achieve the output characteristics of a larger power motor in a traditional solution through a smaller power motor.

[0006] To achieve one of the above purposes, the present invention adopts the following technical solutions:

[0007] Input structure;

[0008] Output structure;

[0009] A transmission module, comprising a spherical roller; the spherical roller can rotate around a first axis, and the spherical roller is in transmission contact with the input structure and the output structure; when the input structure rotates around the input axis, the spherical roller is driven to rotate around the first axis, thereby driving the output structure to rotate; the distance from the position where the input structure contacts the spherical roller to the perpendicular to the first axis is R1, and the distance from the position where the output structure contacts the spherical roller to the perpendicular to the first axis is R2;

[0010] The centrifugal mechanism comprises a centrifugal member; as the rotation speed of the output structure changes, the centrifugal member moves toward or away from the input axis to change the angle of the first axis, thereby changing the ratio of R1 to R2.

[0011] In order to achieve the second of the above-mentioned objectives, the present invention adopts the following technical solutions:

[0012] A hub motor comprises a speed change system as described in the above scheme; the hub motor comprises a fixing part, the input structure and the output structure are rotatably mounted on the fixing part respectively; the spherical roller is movably mounted on the fixing part.

[0013] In order to achieve the third of the above objectives, the present invention adopts the following technical solutions:

[0014] An agricultural unmanned vehicle comprises the hub motor as described in the above scheme.

[0015] The beneficial effects of the present invention are as follows: the speed change system uses spherical rollers as the transmission body of the input and output structures, and is provided with a centrifugal part that performs centrifugal motion with the actual rotation speed of the output structure. As the position of the centrifugal part changes, the inclination angle of the first axis of the spherical roller changes, thereby realizing adaptive adjustment of the transmission ratio and achieving stepless speed change.

[0016] The hub motor and the agricultural unmanned vehicle can realize adaptive and stepless adjustment of the transmission ratio through the cooperation of the centrifugal mechanism and the spherical roller capable of precession motion. The output characteristics of a motor with a fixed transmission ratio can be realized through a smaller power motor, thereby reducing costs, and adaptive speed regulation can be realized in a variety of scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention is further described in detail below based on the accompanying drawings and embodiments.

[0018] Figure 1 It is an exploded schematic diagram of the centrifugal system according to an embodiment of the present invention (the linkage parts are not shown in the figure);

[0019] Figure 2 It is a schematic diagram of the overall structure of the centrifugal system according to an embodiment of the present invention;

[0020] Figure 3 Schematic diagram of the internal structure of the centrifugal system according to an embodiment of the present invention;

[0021] Figure 4 This is one of the cross-sectional views of the centrifugal system according to an embodiment of the present invention (the transmission module is in a low-speed transmission position in the figure);

[0022] Figure 5 for Figure 4 One of the enlarged views of part A in FIG.

[0023] Figure 6 for Figure 4 The second enlarged view of part A in the figure;

[0024] Figure 7This is the second cross-sectional view of the centrifugal system according to the embodiment of the present invention (the transmission module is in the high-speed transmission position in the figure);

[0025] Figure 8 for Figure 7 One of the enlarged views of part B in FIG.

[0026] Fig. 9 for Figure 7 The second enlarged view of part B in the figure;

[0027] Fig.10 It is a structural schematic diagram of the centrifugal roller according to an embodiment of the present invention;

[0028] Fig.11 It is a structural schematic diagram of the roller seat according to an embodiment of the present invention;

[0029] Fig.12 It is a schematic diagram of assembling the centrifugal roller and the roller seat according to an embodiment of the present invention;

[0030] Fig.13 It is a schematic diagram of the assembly of the centrifugal roller, roller seat and linkage member according to an embodiment of the present invention;

[0031] Fig.14 This is a schematic diagram of a transmission module according to an embodiment of the present invention;

[0032] Fig.15 It is a schematic diagram of the cooperation between the centrifugal member and the centrifugal mounting column when the centrifugal mechanism described in the embodiment of the present invention is in different states.

[0033] In the figure: 100, input axis; 200, output axis; 300, first axis; 400, second axis; 500, third line; 10, input structure; 101, input contact portion; 102, input disc portion; 20, output structure; 201, output contact portion; 202, output disc portion; 30, transmission module; 31, spherical roller; 311, first roller portion; 312, second roller portion; 313, connecting shaft portion; 32, roller seat; 321, main seat portion; 3211, shaft hole; 322, second rotating shaft portion; 323, inner extension portion; 33, retaining frame; 331, mounting groove; 41, centrifugal mounting column; 42, centrifugal member; 43, linkage member; 431, slot; 50, elastic member. DETAILED DESCRIPTION

[0034] In order to make the technical problems solved by the present invention, the technical solutions adopted and the technical effects achieved clearer, the technical solutions of the embodiments of the present invention will be further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0035] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected" and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0037] The wheel hub motor is a type of permanent magnet synchronous motor. The wheel hub motor consists of a stator, a rotor and an output structure, and the output structure is generally an end cover. Its working principle is to place permanent magnets and coils on the rotor and stator of the motor, and use the constant magnetic field generated by the permanent magnets to interact with the magnetic field generated by the alternating current flowing in the coils, so that the rotor starts to rotate, and the rotor rotates to drive the output to rotate. The biggest feature of the wheel hub motor is that both the power device and the transmission device are integrated into the wheel hub, thus greatly simplifying the mechanical part of the electric vehicle.

[0038] In the related art, many motors have fixed transmission ratios. The input structure and output structure in the hub motor have a fixed transmission ratio. For example, a planetary reduction assembly is set in the hub motor, which is a fixed transmission ratio. The fixed transmission ratio cannot change the transmission ratio according to the working conditions to achieve low-speed high-torque or high-speed low-torque working conditions when a single motor is driven. It can only meet higher working requirements by increasing the motor output power. This means that in vehicles using hub motors, or in other equipment using fixed transmission ratio motors, the selected motor needs to be upwardly compatible with less common extreme working conditions, resulting in the need to use higher-power motors. However, when high-power motors are used, the value of high power is only reflected in a few situations, which reduces the cost-effectiveness of the entire equipment.

[0039] The present invention provides a speed change system, which can be applied to a permanent magnet motor or a non-permanent magnet motor, and the permanent magnet motor can be but not limited to a hub motor. In the first aspect, the speed change system adopts a spherical roller 31 as the transmission ratio of the input structure 10 and the output structure 20, and the adjustment of the transmission ratio is achieved through the precession motion of the spherical roller 31, wherein the precession motion refers to the motion of a rotating object being subjected to an external force causing its rotation axis to rotate around a certain center, also known as precession motion. In the second aspect, the outer surface of the spherical roller 31 is continuous, and stepless speed change can be achieved. In the third aspect, a centrifugal part 42 that performs centrifugal motion with the actual speed of the motor is designed, and the precession motion of the spherical roller 31 changes with the centrifugal motion of the centrifugal part 42. When the speed change system is applied to the motor, the transmission ratio can be adaptively adjusted according to the actual output speed of the motor. In the fourth aspect, the output can be reduced in low-speed scenarios to obtain higher torque, and the output can be increased in high-speed scenarios to obtain higher speed at the expense of torque. When applied to the wheel motor of an agricultural unmanned vehicle, the agricultural unmanned vehicle can quickly adapt to various terrains or vehicle conditions and give full play to the performance of the motor.

[0040] The present invention provides a hub motor, which can be applied to agricultural unmanned vehicles, and can also be applied to the wheel structure of electric vehicles, electric bicycles, electric motorcycles, electric scooters, electric kickboards, golf carts, intelligent inspection robots, food delivery robots, automatic guided transport vehicles and other equipment. The hub motor adopts the above-mentioned speed change system, and on the first hand, the adaptive adjustment of the transmission ratio can be realized. On the second hand, the hub motor can realize the output characteristics of the larger power motor in the related technology through a smaller power motor, thereby reducing the cost of the hub motor equipment.

[0041] The present invention also provides an agricultural unmanned vehicle, which adopts the aforementioned wheel hub motor. On the one hand, the wheel hub motor of the agricultural unmanned vehicle can realize adaptive adjustment of the transmission ratio, and the transmission ratio changes with the actual speed of the motor. In low-speed scenarios, the wheel hub motor realizes deceleration output to obtain higher torque, which is helpful for vehicle starting and getting out of trouble; in high-speed scenarios, the wheel hub motor realizes speed-up output, sacrificing torque to obtain higher speed, which is helpful for vehicle high-speed cruising. No special controller is required, and no manual control is required to control the movement of the spherical roller 31 to adjust the transmission ratio. The adaptive adjustment of the transmission ratio reduces the control cost and is more intelligent. On the other hand, the cost performance of the whole vehicle can be improved by reducing the cost of the motor in the wheel hub motor vehicle.

[0042] Please continue to refer to Figures 1 to 15 , the speed change system, wheel hub motor and agricultural unmanned vehicle of the present invention are described below.

[0043] The speed change system includes an input structure 10, an output structure 20, a transmission module 30, a centrifugal mechanism and a fixing member.

[0044] The input structure 10 can be rotatably mounted on the fixing member around the input axis 100 , and the output structure 20 can be rotatably mounted on the fixing member around the output axis 200 . In the present invention, the input axis 100 and the output axis 200 are taken as an example to be coincident and parallel.

[0045] The transmission module 30 includes a spherical roller 31 , which can rotate around a first axis 300 passing through the spherical roller 31 , and can also rotate around a second axis 400 . When the spherical roller 31 rotates around both the first axis 300 and the second axis 400 , it performs precession motion relative to the input axis 100 . Figures 4 to 7 A first axis 300 is illustrated in FIG.

[0046] Reference Figures 4 to 9 Optionally, the input structure 10 includes an input disk portion 102 and an input contact portion 101 connected to each other, the output structure 20 includes an output disk portion 202 and an output contact portion 201 connected to each other, the transmission module 30, the centrifugal mechanism, and the fixing member are arranged between the input disk portion 102 and the output disk portion 202, the input contact portion 101 is bent relative to the input disk portion 102, and the output contact portion 201 is bent relative to the output disk portion 202. The spherical roller 31 is in transmission contact with the input structure 10 and the output structure 20 at different positions on the surface of one side of the first axis 300. Among them, the input contact portion 101 and the output contact portion 201 are located on the same side of the first axis 300.

[0047] When the input structure 10 rotates around the input axis 100, the spherical roller 31 is driven to rotate around the first axis 300, thereby driving the output structure 20 to rotate around the output axis 200. Figure 6 , Fig. 9 As shown, the position where the input structure 10 contacts the spherical roller 31 is the first position, and the perpendicular distance from the first position to the first axis 300 is the first distance R1; the position where the output structure 20 contacts the spherical roller 31 is the second position, and the perpendicular distance from the second position to the first axis 300 is the second distance R2. When the spherical roller 31 rotates around the second axis 400, the angle of the first axis 300 relative to the input axis 100 changes, and at this time, the rotation axis of the spherical roller 31 precesses around the input axis 100, and the ratio of R1 to R2 changes, thereby realizing the transmission ratio adjustment.

[0048] The centrifugal mechanism includes a centrifugal member 42. The relative rotation between the centrifugal member 42 and the output structure 20 around the input axis 100 is restricted. As the rotation speed of the output structure 20 changes, the centrifugal member 42 moves toward or away from the input axis 100. When the spherical roller 31 rotates around the second axis 400, R1 and R2 change. The principle of adaptive transmission ratio change is as follows:

[0049] As the actual rotation speed of the output structure 20 changes, the centrifugal member 42 moves toward or away from the input axis 100, causing the spherical roller 31 to rotate around the second axis 400, so that the angle of the first axis 300 changes, thereby changing the ratio of R2 to R1. In the speed change system of the present invention, the input structure 10 is matched with the output structure 20 through the spherical roller 31, and a centrifugal mechanism is also configured between the input structure 10 and the output structure 20, and the centrifugal mechanism includes a centrifugal member 42. The centrifugal member 42 performs centrifugal movement with the rotation speed of the output structure 20, so that the spherical roller 31 rotates around the second axis 400 on the basis of rotating around the first axis 300, and changes the angle of the first axis 300, so as to change the contact position between the transmission member and the input structure 10 and the output structure 20, change the transmission ratio, and realize automatic speed change. The transmission ratio can be adaptively adjusted according to the actual speed of the motor. When the motor is in different application scenarios, the speed and torque can be adaptively adjusted, and the transmission ratio does not need to be adjusted by the control of the controller or manual adjustment, thereby reducing equipment cost and control cost.

[0050] The speed change system of the present invention adopts a spherical roller 31 as the spherical roller 31. By changing the degree of centrifugation of the centrifugal member 42, the spherical roller 31 precesses to achieve stepless adjustment of the transmission ratio. Compared with other stepless speed change designs, it has low requirements for axial space and is convenient for integration into the motor module. In addition, the advantage of using a spherical roller 31 with precession motion is that the spherical roller 31 is a rotating body formed by a circle rotating around a first axis 300. When the input structure 10 and the output structure 20 are in contact, the R1 and R2 values ​​can be changed by changing the angle of the first axis 300 to achieve stepless speed change. The speed change system of the present invention requires a small number of parts, which is conducive to the compact and miniaturized design of the transmission.

[0051] In the related art, a planetary reduction system is configured in a motor such as a hub motor to achieve deceleration, but the planetary reduction system has a fixed transmission ratio and the transmission ratio cannot be changed. In some hub motors, although the transmission ratio of the speed change system is variable, it can only achieve one function of deceleration or acceleration, and cannot meet the needs of various application scenarios. In the speed change system of the present invention, as the output structure 20 rotates, the degree of the centrifugal part 42 thrown out under the action of centrifugal force changes, and the transmission module 30 can be moved radially inward or outward, that is, the two functions of deceleration transmission and acceleration transmission can be realized. Compared with the speed change system that can only achieve deceleration output or acceleration output, the speed change system of the present invention can easily adapt to more application scenarios through a simple and compact structure, and has high practicality.

[0052] Please continue to refer to Figures 4 to 7 In order to adapt the speed change system to more application scenarios, the speed change system of the present invention is configured to reduce the output speed or increase the output speed. The spherical roller 31 includes two opposite ends, one end of which is the inner end of the spherical roller 31, and the second end of which is the outer end of the spherical roller 31. The inner end is closer to the input axis 100 than the outer end.

[0053] The spherical roller 31 has a low-speed transmission state, an intermediate state, and a high-speed transmission state. For the convenience of description, a line passing through the inner end and the outer end is drawn in the figure, and the line is the third line 500. The following describes the adjustment of the swing direction of the spherical roller 31 to achieve the principle of speed reduction transmission and speed increase transmission by adjusting the angle of the third line 500 relative to the input axis 100.

[0054] Figures 4 to 6 In the embodiment, the spherical roller 31 is in a low-speed transmission state. As the actual speed of the output structure 20 decreases, the centrifugal member 42 moves inward, and the spherical roller 31 rotates around the second axis 400, and the angle of the first axis 300 changes. Figure 6 As shown, R2 is smaller than R1, and the ratio of R2 to R1 is less than 1. The linear speed obtained by the output structure 20 at the second position is small and the torque is large, which is suitable for low-speed and high-torque scenarios, and the speed change system is used as a reducer.

[0055] Figures 7 to 9 In the embodiment, the spherical roller 31 is in a high-speed transmission state. As the actual speed of the output structure 20 increases, the centrifugal member 42 moves outward, and the spherical roller 31 rotates around the second axis 400, and the angle of the first axis 300 changes. Fig. 9 As shown, R2 is greater than R1, and the ratio of R2 to R1 is greater than 1. The linear speed obtained by the output structure 20 at the second position is large and the torque is small, which is suitable for high-speed and low-torque scenarios, and the speed change system is used as an accelerator.

[0056] In order to facilitate understanding of the position of the spherical roller 31 in different states, refer to Figures 4 to 6When the spherical roller 31 is in a low-speed transmission state, the third line 500 is inclined from the outside to the inside toward the direction close to the output structure 20, and the outer end is closer to the input structure 10 relative to the inner end. Figures 7 to 9 When the spherical roller 31 is in a high-speed transmission state, the third line 500 is inclined from outside to inside toward the direction close to the input structure 10, and the outer end is closer to the output structure 20 relative to the inner end. When the spherical roller 31 is in an intermediate state, the third line 500 is perpendicular to the input axis 100.

[0057] Please continue to refer to Figures 4 to 11 In order to make the speed change system structure more compact, the first axis 300 of the spherical roller 31 and the axis are configured to pass through the center of the spherical roller 31. In this way, during the speed change process, the spherical roller 31 only rotates around the first axis 300 at the original position to realize transmission, and synchronously rotates around the second axis 400 to adjust the angle of the first axis 300. During the speed change process, the spherical roller 31 is always in the same position in the speed change system to avoid interference with other parts. The precession motion of the spherical roller 31 does not occupy or occupies very little radial space or axial space, and the axial position between the input structure 10 and the output structure 20 does not change, which is conducive to making the transmission compact and miniaturized.

[0058] In other embodiments, the second axis 400 may not pass through the center of the spherical roller 31 , and the position of the spherical roller 31 may change during the speed change process.

[0059] Please continue to refer to Figures 1 to 7 , Fig.11 , Fig.12 The transmission module 30 includes a roller seat 32 and a retaining frame 33. The spherical roller 31 is rotatably mounted on the roller seat 32. The spherical roller 31 can rotate relative to the roller seat 32 around the first axis 300, and the spherical roller 31 can rotate with a single degree of freedom. The roller seat 32 is rotatably mounted on the retaining frame 33. The roller seat 32 can rotate relative to the retaining frame 33 around the second axis 400, and the roller seat 32 can rotate with a single degree of freedom. With the retaining frame 33 as a reference system, the spherical roller 31 precesses relative to it.

[0060] In this embodiment, through the arrangement of the roller seat 32 and the retaining frame 33, the rotation of the two degrees of freedom of the spherical roller 31 between the input structure 10 and the output structure 20 is decoupled into two rotation installations, so that the rotation of the two degrees of freedom is realized by the cooperation between the spherical roller 31 and the roller seat 32, and the roller seat 32 and the retaining frame 33 respectively. On the one hand, the rotation of the two degrees of freedom is smoother, and the transmission of the spherical roller 31 and the adjustment of the transmission mode of the spherical roller 31 are more reliable; on the other hand, due to the configuration of the roller seat 32, the centrifugal mechanism can adjust the angle of the roller seat 32 on the retaining frame 33 through the cooperation between the roller seat 32 and the centrifugal mechanism, thereby avoiding interference between the centrifugal mechanism and the spherical roller 31.

[0061] In other embodiments, a cross-axis universal joint is provided between the spherical roller 31 and the retaining frame 33 .

[0062] The spherical roller 31 and the roller seat 32 can be configured in at least the following two ways:

[0063] Configuration method 1:

[0064] Please refer to Figures 10 to 12 , Figures 4 to 9 The roller seat 32 includes a main seat portion 321 , and the spherical roller 31 includes a first roller portion 311 and a second roller portion 312 disposed on opposite sides of the main seat portion 321 .

[0065] The main seat portion 321 is provided with an axial hole 3211, and the spherical roller 31 includes a connecting shaft portion 313, which is provided in the axial hole 3211, and the two ends of the connecting shaft portion 313 are respectively connected to the first roller portion 311 and the second roller portion 312. The first roller portion 311, the connecting shaft portion 313, and the second roller portion 312 are sequentially connected along the direction of the first axis 300. The outer surfaces of the first roller portion 311 and the second roller portion 312 are two parts within the same spherical surface.

[0066] For example, the first roller part 311 and the second roller part 312 can be configured as a split structure, and the two roller parts can be assembled to the two sides of the main seat part 321 and then fixed to achieve the assembly of the spherical roller 31 and the main seat part 321. The main seat part 321 can also be configured as two half seats, and the two half seats are inserted into the annular groove of the spherical roller 31 and then fixed to achieve the assembly of the spherical roller 31 and the main seat part 321. It should be understood that in some embodiments, the spherical roller 31 and the main seat part 321 can also be integrally formed through some processes, or assembled by other methods.

[0067] Configuration method 2:

[0068] The roller seat 32 includes a main seat portion 321, and the spherical roller 31 includes a first roller portion 311 and a second roller portion 312 disposed on opposite sides of the main seat portion 321. Connecting shafts are disposed on opposite sides of the main seat portion 321, and the first roller portion 311 and the main seat portion 321, and the second roller portion 312 and the main seat portion 321 are rotatably connected through the connecting shafts, and the first axis 300 coincides with the center line of the connecting shafts.

[0069] In both configuration mode 1 and configuration mode 2, the spherical roller 31 can be rotatably installed on the roller seat 32, the spherical roller 31 can rotate around the center line of the roller seat 32, and the roller seat 32 can provide good support for the spherical roller 31, so that when the centrifugal mechanism acts on the roller seat 32, the rotation of the roller seat 32 around the second axis 400 can drive the angle of the first axis 300 to be adjusted with higher precision.

[0070] Please continue to refer to Figure 2 The roller seat 32 is rotatably connected to the retaining frame 33. The roller seat 32 includes a second rotating shaft portion 322, and the second rotating shaft portions 322 are respectively arranged on opposite sides of the main seat portion 321. The second rotating shaft portion 322 and the main seat portion 321 can be integrally formed, and both ends of the roller seat 32 are rotatably connected to the retaining frame 33 through the second rotating shaft portions 322.

[0071] The connecting line of the two second rotating shaft portions 322 coincides with the second axis 400, the center line of the connecting shaft portion 313 coincides with the first axis 300, and the intersection of the first axis 300 and the second axis 400 is located at the center of the shaft hole 3211 of the main seat portion 321, so that the radial position and axial position on the retaining frame 33 remain unchanged when the spherical roller 31 makes precession motion.

[0072] Compared with providing the second rotating shaft on the retaining frame 33 , in this embodiment, the second rotating shaft portion 322 is provided on the roller seat 32 to realize the rotational connection between the roller seat 32 and the retaining frame 33 , thereby simplifying the structure of the retaining frame 33 .

[0073] Please continue to refer to Figures 1 to 3 , Fig.13 , Fig.14 In order to improve the transmission efficiency of the entire transmission system, the transmission system includes a plurality of spherical rollers 31 and a plurality of roller seats 32. The plurality of spherical rollers 31 and the plurality of roller seats 32 are arranged at intervals around the input axis 100. The plurality of spherical rollers 31 are arranged around the input axis 100, which can increase the contact area between the input structure 10 and the spherical rollers 31, and between the output structure 20 and the spherical rollers 31, so as to improve the transmission efficiency.

[0074] Please continue to refer to Figure 1 , Figure 2 , Fig.12 In order to install multiple transmission modules 30 , the retaining frame 33 is provided with multiple installation grooves 331 at intervals around the input axis 100 .

[0075] The side of the retainer 33 close to the input axis 100 (i.e., the inner side of the retainer 33) forms an inner notch of the mounting groove 331, and the side away from the input axis 100 (i.e., the outer side of the retainer 33) forms an outer notch of the mounting groove 331. The outer notch of the retainer 33 provides a clearance so that the spherical roller 31 extends out of the mounting groove 331, or the input structure 10 and the output structure 20 extend into the mounting groove 331, thereby achieving transmission contact between the spherical roller 31 and the input structure 10, and between the spherical roller 31 and the output structure 20.

[0076] The centrifugal mechanism is arranged on the inner side of the retaining frame 33, and the inner groove of the retaining frame 33 provides a clearance so that the roller seat 32 contacts the centrifugal mechanism through the inner groove. When the centrifugal member 42 of the centrifugal mechanism performs centrifugal motion, force is applied to the roller seat 32, thereby realizing the centrifugal mechanism to adjust the angle of the first axis 300 of the roller seat 32.

[0077] Through the structural design of this retaining frame 33, groove walls of the retaining frame 33 mounting groove 331 can be provided on both sides of the roller seat 32 in the circumferential direction around the input axis 100, providing a position for the roller seat 32 to be rotatably mounted to the retaining frame 33, so as to realize the second axis 400 in the radial plane, so that when the roller seat 32 rotates around the second axis 400, the angle of the first axis 300 can be adjusted.

[0078] Please continue to refer to Figure 1 , Figure 2 , Figures 10 to 14 The roller seat 32 includes a main seat portion 321, the spherical roller 31 is rotatably mounted on the main seat portion 321 via a first axis, and the main seat portion 321 is rotatably mounted on the groove wall of the mounting groove 331 via a second axis; the center line of the first axis is the first axis 300, and the center line of the second axis is the second axis 400. In this embodiment, the first axis is the connecting axis portion 313 of the spherical roller 31, and the second axis is the second axis portion of the roller seat 32.

[0079] The roller seat 32 includes a main seat portion 321, the left and right sides of the main seat portion 321 are connected to the second shaft portion, and the inner side of the main seat portion 321 is connected to the inner extension portion 323. The inner extension portion 323 of the roller seat 32 is used to cooperate with the centrifugal mechanism, so that after the centrifugal force acts on the roller seat 32, the roller seat 32 can rotate relative to the retaining frame 33 around the second axis 400. The inner extension portion 323 extends out of the inner notch of the retaining frame 33, and the centrifugal member 42 directly or indirectly contacts the inner extension portion 323 in at least part of the case, so that the centrifugal member 42 can transmit force to the inner extension portion 323 during centrifugal motion, so that the inner extension portion 323 swings toward the input structure 10 or the output structure 20, so that the roller seat 32 drives the spherical roller 31 to rotate and swing around the second axis 400, adjust the angle of the first axis 300, and adjust the transmission ratio.

[0080] Please continue to refer to Figures 3 to 9 The centrifugal mechanism includes a linkage member 43, and the linkage member 43 is configured between the plurality of centrifugal members 42 and the plurality of transmission modules 30. The inner extensions 323 of the plurality of roller seats 32 are movably mounted to the linkage member 43, and the plurality of centrifugal members 42 are in contact with the linkage member 43 at the same time. The linkage member 43 is movably configured between the input structure 10 and the output structure 20, and the linkage member 43 is configured to be movable in the axial direction.

[0081] The linkage member 43 can move along the direction of the input axis 100 under the action of the centrifugal member 42 to drive the roller seat 32 to rotate around the second axis 400. When the actual speed of the output structure 20 increases, multiple centrifugal members 42 are simultaneously thrown outward, and the linkage member 43 moves axially. Since one end of the roller seat 32 is movably mounted on the linkage member 43 through the inner extension 323, and the other end is rotatably mounted on the retaining frame 33, when the linkage member 43 moves axially, it pushes the inner extension 323 to move axially, thereby driving the roller seat 32 to rotate around the second axis 400 relative to the retaining frame 33 around the second axis 400, so as to achieve the angle adjustment of the first axis 300 and the transmission ratio adjustment.

[0082] The centrifugal forces of the plurality of centrifugal members 42 act evenly on the linkage member 43, which then converts the centrifugal forces into axial movement, and the inner extension 323 of the roller seat 32 converts the axial movement into the rotational movement of the spherical roller 31 around the second axis 400 relative to the retaining frame 33, thereby realizing reliable linkage between the centrifugal members 42 and the spherical roller 31. In addition, compared with the method in which the centrifugal members 42 and the roller seats 32 are connected and matched one by one, the method of this embodiment causes the forces of the plurality of centrifugal members 42 to act evenly on the linkage member 43, and then acts evenly on the plurality of roller seats 32 through the linkage member 43, so that even if one centrifugal member 42 fails, the spherical roller 31 at the corresponding position can also perform linkage movement driven by the linkage member 43, and the reliability is higher.

[0083] In other embodiments, the linkage member 43 may not be provided, and the plurality of centrifugal members 42 may be in one-to-one contact with the plurality of roller seats 32 .

[0084] Please continue to refer to Figure 3 , Fig.11 The linkage member 43 is an annular structure. A slot 431 is provided on the side of the linkage member 43 away from the input axis 100. The inner extension 323 is inserted into the slot 431. In this way, the position of the linkage member 43 changes in the axial direction by pushing the inner extension 323 against the slot 431 through the slot wall, so that the roller seat 32 can be flipped relative to the retaining frame 33 around the second axis 400, similar to the movement of a lever. This assembly method can realize that the linkage member 43 drives the roller seat 32 to flip to adjust the angle of the first axis 300, and the roller seat 32 and the linkage member 43 are easy to disassemble and assemble. It is only necessary to insert or pull out the inner extension 323 into or out of the slot 431 without using tools.

[0085] It should be noted that when the inward extensions 323 of the multiple roller seats 32 are inserted into the linkage member 43 from multiple directions, the linkage member 43 is movably installed between the input structure 10 and the output structure 20, and there is no need to use other parts to fix the linkage member 43. In this way, the speed change system has a small number of parts, is easy to disassemble and assemble, and has a compact structure.

[0086] The spherical roller 31 has a low-speed transmission state, an intermediate state and a high-speed transmission state. The speed change system includes an elastic member 50 .

[0087] The power for adjusting the spherical roller 31 to the high-speed transmission state is provided by the centrifugal part 42. The greater the actual rotation speed of the output structure 20, the greater the degree to which the centrifugal part 42 is thrown outward, and the elastic part 50 undergoes elastic deformation under the action of the centrifugal part 42 to accumulate elastic potential energy. The greater the degree to which the third line 500 of the spherical roller 31 tilts from the outside to the inside toward the output structure 20, the smaller R1 is, the larger R2 is, the ratio of R2 to R1 is greater than 1, the smaller the transmission ratio is, and it is suitable for high-speed and low-torque scenarios.

[0088] The power for adjusting the spherical roller 31 to the low-speed transmission state is provided by the elastic member 50. The smaller the actual rotation speed of the output structure 20, the smaller the degree to which the centrifugal member 42 is thrown outward, and the smaller the force transmitted from the centrifugal member 42 to the elastic member 50. The elastic force of the elastic member 50 can act on the roller seat 32 of the spherical roller 31 to make the roller seat 32 rotate around the second axis 400. The greater the degree to which the third line 500 of the spherical roller 31 is inclined from the outside to the inside toward the direction close to the input structure 10, the larger R1 is, the smaller R2 is, the ratio of R2 to R1 is less than 1, the larger the transmission ratio is, and it is suitable for low-speed and high-torque scenarios.

[0089] Please continue to refer to Figure 1 , Figures 4 to 7 The elastic member 50 can be configured as follows: the centrifugal mechanism includes a plurality of centrifugal members 42, which are arranged at intervals around the input axis 100; the centrifugal mechanism includes an elastic member 50; along the direction of the input axis 100, opposite sides of the linkage member 43 contact the centrifugal member 42 and the elastic member 50 respectively.

[0090] The linkage member 43 is always in contact with the centrifugal member 42 under the elastic force of the elastic member 50, so the angular movement of the centrifugal member 42 will push the linkage member 43, so that the linkage member 43 drives the roller seat 32 to rotate, thereby changing the transmission ratio. The higher the speed, the greater the movement angle of the centrifugal member 42, the greater the rotation angle of the spherical roller 31 around the second axis 400, and the smaller the transmission ratio; therefore, it can be achieved that a high torque and low speed output is achieved with a large transmission ratio at low speed, and a high speed and low torque output is achieved with a small transmission ratio at high speed.

[0091] The linkage member 43 can move along the first axial direction under the thrust of the centrifugal member 42. In this embodiment, the first direction is the direction axially approaching the input structure 10. The linkage member 43 can move along the second axial direction under the elastic force of the elastic member 50. In this embodiment, the second direction is the direction axially approaching the output structure 20.

[0092] Please continue to refer to Figure 1 , Figures 4 to 9, the elastic member 50 is arranged in the following manner. The elastic member 50 is sandwiched between the input structure 10 and the linkage member 43. One end of the centrifugal member 42 is hingedly mounted to the output structure 20, and the other end is a free end, and the free end of the centrifugal member 42 abuts against the side of the linkage member 43 away from the output structure 20. For example, Figures 7 to 9 When the force of the centrifugal member 42 being thrown outward is relatively large, the free end of the centrifugal member 42 pushes the linkage member 43, and at this time, the elastic member 50 is continuously compressed to accumulate elastic force. Figures 4 to 6 In the embodiment, when the centrifugal force of the centrifugal member 42 is small, the elastic force of the elastic member 50 pushes the linkage member 43 downward.

[0093] The linkage member 43 and the retaining frame 33 are respectively provided with limiting grooves, and the elastic member 50 is a spring, and both ends of the spring are respectively inserted into the limiting grooves on both sides.

[0094] Please continue to refer to Figure 1 , Figure 3 , Figures 4 to 7 , Fig.13 The centrifugal mechanism includes a centrifugal mounting column 41 and a plurality of centrifugal components 42. The centrifugal mounting column 41 is connected to the output structure 20 in a rotationally limited manner. The plurality of centrifugal components 42 are arranged at intervals around the input axis 100. The centrifugal component 42 is a centrifugal swinging component. One end of the centrifugal component 42 is hinged to the centrifugal mounting column 41, and the other end is a free end. The centrifugal component 42 is used to push the roller seat 32 to rotate around the second axis 400 during centrifugal swinging.

[0095] By providing a plurality of centrifugal members 42, when the output structure 20 rotates, the plurality of centrifugal members 42 are scattered outward at different positions, and exert force evenly on different positions of the linkage member 43, so that the linkage member 43 can stably move along the axial direction, and the linkage member 43 is more sensitive to the feedback of the change in the magnitude of the centrifugal force, and the angle of the first axis 300 of the spherical roller 31 can be more accurately adjusted according to the magnitude of the centrifugal force. By providing a centrifugal mounting column 41, the plurality of centrifugal members 42 are hingedly mounted on the same centrifugal mounting column 41, compared with the plurality of centrifugal swinging members being directly hingedly mounted at different positions of the output structure 20, a modular design of the centrifugal mechanism is realized, which is convenient for disassembly, assembly and maintenance.

[0096] In other embodiments, the centrifugal mounting column 41 may be eliminated, and a plurality of protrusions may be directly welded or integrally formed on the inner side of the output module, and a plurality of centrifugal members 42 may be hingedly mounted on the protrusions on the inner side of the output module.

[0097] The present invention also provides a wheel hub motor, which comprises the speed change system.

[0098] The wheel hub motor includes a fixing part, and the input structure 10 and the output structure 20 are rotatably mounted on the fixing part respectively; the spherical roller 31 is movably mounted on the fixing part. The wheel hub motor includes a stator; the input structure 10 is a rotor, and the fixing part is an end cover; the end cover is fixed to the stator, and an installation cavity is formed between the end cover and the stator; the input structure 10, the output structure 20, and the transmission module 30 are arranged in the installation cavity.

[0099] The input structure 10 is rotatably mounted on the fixing member via a first bearing, and the output structure 20 is rotatably mounted on the fixing member via a second bearing.

[0100] The present invention also provides an agricultural unmanned vehicle, which is used to perform operations such as spraying and sowing. The agricultural unmanned vehicle includes a vehicle body and a plurality of wheels rotatably mounted on the vehicle body; one or more wheels, the wheel includes a wheel hub, a wheel body and the aforementioned wheel hub motor, the wheel hub is fixed to the output structure 20 of the wheel hub motor, and the wheel body is sleeved outside the wheel hub.

[0101] In the description of this article, it should be understood that the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplified operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0102] In the description of this specification, the description with reference to the terms "an embodiment", "example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example.

[0103] In addition, it should be understood that although this specification is described according to implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

[0104] The technical principle of the present invention is described above in conjunction with specific embodiments. These descriptions are only for explaining the principle of the present invention and cannot be interpreted as limiting the scope of protection of the present invention in any way. Based on the explanations herein, those skilled in the art can associate other specific implementations of the present invention without paying creative labor, and these methods will fall within the scope of protection of the present invention.

Claims

1. A speed change system, characterized in that: include: Input structure (10); Output structure (20); A transmission module (30) comprises a spherical roller (31); the spherical roller (31) can rotate around a first axis (300), and the spherical roller (31) is in transmission contact with the input structure (10) and the output structure (20); when the input structure (10) rotates around the input axis (100), the spherical roller (31) is driven to rotate around the first axis (300), thereby driving the output structure (20) to rotate; the distance from the position where the input structure (10) contacts the spherical roller (31) to the perpendicular to the first axis (300) is R1, and the distance from the position where the output structure (20) contacts the spherical roller (31) to the perpendicular to the first axis (300) is R2; A centrifugal mechanism comprises a centrifugal member (42) arranged between the output structure (20) and the spherical roller (31); as the rotation speed of the output structure (20) changes, the centrifugal member (42) moves in a direction approaching or away from the input axis (100), so that the angle of the first axis (300) changes, thereby changing the ratio of R2 to R1.

2. The speed change system according to claim 1, characterized in that: The spherical roller (31) is movably installed between the input structure (10) and the output structure (20); the spherical roller (31) is configured to be rotatable around the first axis (300) and around the second axis (400); When the centrifugal member (42) moves in a direction approaching or away from the input axis (100), the spherical roller (31) rotates around the second axis (400), so that the angle of the first axis (300) changes.

3. The speed change system according to claim 2, characterized in that: The spherical roller (31) has a low-speed transmission state and a high-speed transmission state; when the spherical roller (31) is in the low-speed transmission state, the R2 is smaller than the R1; when the spherical roller (31) is in the high-speed transmission state, the R2 is larger than the R1.

4. The speed change system according to claim 2, characterized in that: The transmission module (30) comprises a roller seat (32) and a retaining frame (33); The spherical roller (31) is rotatably mounted on the roller seat (32), and the spherical roller (31) can rotate relative to the roller seat (32) around the first axis (300); the roller seat (32) is rotatably mounted on the retaining frame (33), and the roller seat (32) can rotate relative to the retaining frame (33) around the second axis (400).

5. The speed change system according to claim 4, characterized in that: The roller seat (32) comprises a main seat portion (321), and the spherical roller (31) comprises a first roller portion (311) and a second roller portion (312) arranged on opposite sides of the main seat portion (321); The main seat portion (321) is provided with an axial hole (3211), and the spherical roller (31) includes a connecting shaft portion (313), and the connecting shaft portion (313) is provided in the axial hole (3211), and the first roller portion (311), the connecting shaft portion (313), and the second roller portion (312) are connected in sequence along the direction of the first axis (300); or, connecting shafts are provided on opposite sides of the main seat portion (321), and the first roller portion (311) and the main seat portion (321), and the second roller portion (312) and the main seat portion (321) are rotatably connected via the connecting shafts, and the first axis (300) coincides with a center line of the connecting shaft.

6. The speed change system according to any one of claims 4 to 5, characterized in that: The roller seat (32) comprises a main seat portion (321) and second rotating shaft portions (322) arranged on two opposite sides of the main seat portion (321); The spherical roller (31) is rotatably mounted on the main seat portion (321); the second rotating shaft portion (322) on both sides of the roller seat (32) is rotatably connected to the retaining frame (33).

7. The speed change system according to claim 4, characterized in that: The speed change system comprises a plurality of spherical rollers (31) and a plurality of roller seats (32); the plurality of spherical rollers (31) and the plurality of roller seats (32) are arranged at intervals around the input axis (100).

8. The speed change system according to claim 7, characterized in that: The retaining frame (33) comprises a plurality of mounting grooves (331) arranged at intervals around the input axis (100); The side of the retaining frame (33) close to the input axis (100) forms an inner notch of the mounting groove (331), and the side away from the input axis (100) forms an outer notch of the mounting groove (331); The centrifugal mechanism is arranged on the inner side of the retaining frame (33); the roller seat (32) or the spherical roller (31) cooperates with the centrifugal mechanism through the avoidance position of the inner notch; the spherical roller (31) contacts the input structure (10) and the output structure (20) through the avoidance position of the outer notch.

9. The speed change system according to claim 8, characterized in that: The roller seat (32) comprises a main seat portion (321), the spherical roller (31) is rotatably mounted on the main seat portion (321) via a first shaft, and the main seat portion (321) is rotatably mounted on a groove wall of the mounting groove (331) via a second shaft; the center line of the first shaft is the first axis (300), and the center line of the second shaft is the second axis (400); The roller seat (32) comprises an inwardly extending portion (323) connected to the main seat portion (321), and the centrifugal member (42) acts on the inwardly extending portion (323) so that the roller seat (32) drives the spherical roller (31) to rotate around the second axis (400).

10. The speed change system according to claim 9, characterized in that: The centrifugal mechanism comprises a linkage member (43), and the inner extensions (323) of the plurality of roller seats (32) are movably mounted on the linkage member (43); the centrifugal member (42) is in contact with the linkage member (43).

11. The speed change system according to claim 10, characterized in that: The linkage member (43) is an annular structure. A slot (431) is provided on the side of the linkage member (43) away from the input axis (100), and the inner extension (323) is inserted into the slot (431). The linkage member (43) is movably installed between the input structure (10) and the output structure (20). The linkage member (43) can move along the direction of the input axis (100) under the action of the centrifugal member (42) to drive the roller seat (32) to rotate around the second axis (400).

12. The speed change system according to claim 11, characterized in that: The centrifugal mechanism comprises a plurality of centrifugal members (42), and the plurality of centrifugal members (42) are arranged at intervals around the input axis (100); the centrifugal mechanism comprises an elastic member (50); along the direction of the input axis (100), the centrifugal member (42) and the elastic member (50) are arranged on opposite sides of the linkage member (43); The linkage member (43) can move along a first axial direction under the thrust of the centrifugal member (42); and the linkage member (43) can move along a second axial direction under the elastic force of the elastic member (50).

13. The speed change system according to claim 12, characterized in that: The elastic member (50) is sandwiched between the linkage member (43) and the input structure (10); one end of the centrifugal member (42) is hingedly mounted to the output structure (20), and the other end is a free end, and the free end of the centrifugal member (42) abuts against a side of the linkage member (43) that is away from the output structure (20).

14. The speed change system according to claim 7, characterized in that: The centrifugal mechanism comprises a centrifugal mounting column (41) and a plurality of centrifugal components (42), wherein the centrifugal mounting column (41) is connected to the output structure (20), and the plurality of centrifugal components (42) are arranged at intervals around the input axis (100); The centrifugal component (42) is a centrifugal swinging component, one end of the centrifugal component (42) is hinged to the centrifugal mounting column (41), and the other end is a free end; the centrifugal component (42) is used to push the roller seat (32) to rotate around the second axis (400) during centrifugal swinging.

15. A hub motor, characterized in that: It comprises a speed change system as claimed in any one of claims 1 to 14; the hub motor comprises a fixing part, the input structure (10) and the output structure (20) are rotatably mounted on the fixing part respectively; the spherical roller (31) is movably mounted on the fixing part.

16. An agricultural unmanned vehicle, characterized in that: Comprising the hub motor as claimed in claim 15.

Images