Variable speed system, wheel hub motor and agricultural unmanned vehicle

Abstract

The application discloses a variable speed system, a hub motor and an agricultural unmanned vehicle, and belongs to the technical field of transmission equipment. The variable speed system adopts a spherical roller as a transmission body of an input and output structure, and is provided with a centrifugal part which performs centrifugal motion according to an actual rotating speed of the output structure. With the change of the position of the centrifugal part, the inclination angle of the first axis of the spherical roller changes, the adaptive adjustment of the transmission ratio is realized, and stepless speed change is realized. The hub motor and the agricultural unmanned vehicle can cooperate with the spherical roller which can perform prograde motion through the centrifugal mechanism, the transmission ratio can be adaptively and steplessly adjusted, the output characteristics of the motor with fixed transmission ratio can be realized through a smaller power motor, the cost is reduced, and adaptive speed regulation can be realized in various scenes.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of transmission equipment, in particular to a variable speed system, a hub motor and an agricultural unmanned vehicle. BACKGROUND

[0002] In the related art, many motors have fixed transmission ratios, such as many hub motors, which cannot change the transmission ratio to achieve a low-speed high-torque or a high-speed low-torque working state when a single motor is driven, and can only increase the motor output power to meet higher working requirements. This makes it necessary to select a motor that is upward compatible with less common extreme conditions when using a vehicle with a hub motor or other equipment using a motor with a fixed transmission ratio, resulting in the need to use a higher power motor. However, high-power motors are only needed in a few cases, which reduces the cost performance of the entire device. SUMMARY

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

[0004] The second purpose of the embodiments of the present application is to provide a hub motor that can adaptively adjust the transmission ratio according to the actual speed of the motor.

[0005] The third purpose of the embodiments of the present application is to provide an agricultural unmanned vehicle that can achieve the output characteristics of a larger power motor in a traditional scheme using a smaller power motor.

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

[0007] an input structure;

[0008] an output structure;

[0009] a transmission module including a spherical roller; the spherical roller is rotatable about a first axis, and the spherical roller is in drivable contact with the input structure and the output structure; when the input structure rotates about an input axis, it drives the spherical roller to rotate about the first axis, thereby driving the output structure to rotate; the vertical distance from the position where the input structure contacts the spherical roller to the first axis is R1, and the vertical distance from the position where the output structure contacts the spherical roller to the first axis is R2;

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

[0011] To achieve the above-mentioned purpose two, the application adopts the following technical solutions:

[0012] A wheel hub motor comprising the variable speed system as described above; the wheel hub motor comprises a fixed part, the input structure and the output structure are rotatably mounted on the fixed part; the spherical roller is movably mounted on the fixed part.

[0013] To achieve the above-mentioned purpose three, the application adopts the following technical solutions:

[0014] An agricultural unmanned vehicle comprising the wheel hub motor as described above.

[0015] The beneficial effects of the application are: the variable speed system adopts a spherical roller as a transmission body of the input and output structure, and sets a centrifugal part that moves centrifugally with the actual rotating speed of the output structure; with the change of the position of the centrifugal part, the inclination angle of the first axis of the spherical roller changes, the self-adaptive adjustment of the transmission ratio is realized, and stepless speed change is realized.

[0016] The wheel hub motor and the agricultural unmanned vehicle can realize self-adaptive and stepless adjustment of the transmission ratio by cooperating the centrifugal mechanism with the spherical roller that can move in the advancing motion, can realize the output characteristics of the motor with fixed transmission ratio by a smaller power motor, reduce the cost, and realize adaptive speed regulation in various scenes. BRIEF DESCRIPTION OF DRAWINGS

[0017] The application will be further described in detail below according to the drawings and examples.

[0018] Figure 1 The exploded schematic view of the centrifugal system described in the embodiment of the application (the linkage is not shown in the figure);

[0019] Figure 2 The overall structure schematic view of the centrifugal system described in the embodiment of the application;

[0020] Figure 3 The internal structure schematic view of the centrifugal system described in the embodiment of the application;

[0021] Figure 4 One of the cross-sectional views of the centrifugal system described in the embodiment of the application (the transmission module is in the low-speed transmission position in the figure);

[0022] Figure 5 One of the enlarged views of A part in the figure; Figure 4

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

[0024] Figure 7 ​​Figure 2 is a sectional view of the centrifugal system according to an embodiment of the present application (the transmission module is in the high-speed transmission position);

[0025] Figure 8 Figure 1 is a sectional view of the centrifugal system according to an embodiment of the present application (the transmission module is in the low-speed transmission position); Figure 7 Figure 3 is an enlarged view of part B in Figure 1;

[0026] Figure 9 Figure 4 is another enlarged view of part B in Figure 1; Figure 7 Figure 5 is an enlarged view of part B in Figure 2;

[0027] Figure 10 Figure 6 is a structural schematic view of the centrifugal roller according to an embodiment of the present application;

[0028] Figure 11 Figure 7 is a structural schematic view of the roller seat according to an embodiment of the present application;

[0029] Figure 12 Figure 8 is an assembly schematic view of the centrifugal roller and the roller seat according to an embodiment of the present application;

[0030] Figure 13 Figure 9 is an assembly schematic view of the centrifugal roller, the roller seat and the linkage according to an embodiment of the present application;

[0031] Figure 14 Figure 10 is a schematic view of the transmission module according to an embodiment of the present application;

[0032] Figure 15 Figure 11 is a schematic view of the cooperation between the centrifugal member and the centrifugal mounting column when the centrifugal mechanism is in different states according to an embodiment of the present application.

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

[0034] In order to make the technical problems solved by the present application, the technical solutions adopted and the technical effects reached more clear, the technical solutions of the embodiments of the present application will be further described in detail below with reference to the drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative work fall into the protection scope of the present application.

[0035] In the description of the present application, unless explicitly defined and limited, the terms "connected", "fixed" should be understood broadly, for example, can be fixed connection, can also be detachable connection or integral; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through intermediate medium, can be the internal communication of two elements or the interaction relationship of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0036] In the present application, unless explicitly defined and limited, the first feature "on" or "under" the second feature can include that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, the first feature "on", "above" and "on" the second feature includes that the first feature is directly above and obliquely above the second feature, or only indicates that the first feature is higher than the second feature in horizontal height. The first feature "under", "below" and "below" the second feature includes that the first feature is directly below and obliquely below the second feature, or only indicates that the first feature is lower than the second feature in horizontal height.

[0037] The wheel hub motor is a kind of permanent magnet synchronous motor, which is composed of stator, rotor and output structure, and the output structure is generally end cover. Its working principle is to place permanent magnets and coils on the rotor and stator of the motor, and utilize the interaction between the constant magnetic field generated by the permanent magnets and the magnetic field generated by the alternating current flowing in the coils to make the rotor start to rotate, and the rotation of the rotor drives the output to rotate. The biggest feature of the wheel hub motor is to integrate the power device and the transmission device into the wheel hub, so that the mechanical part of the electric vehicle is greatly simplified.

[0038] In the related art, many motors have a fixed transmission ratio. The input structure and the output structure in the hub motor have a fixed transmission ratio. For example, the planetary reduction assembly in the hub motor has a fixed transmission ratio. The fixed transmission ratio cannot change the transmission ratio according to the working condition to realize the working state of low speed and high torque or high speed and low torque when a single motor is driven. Only by increasing the output power of the motor can the higher working requirement be met. This makes the motor selected for the vehicle using the hub motor or other equipment using the motor with a fixed transmission ratio need to be compatible with the less common extreme working condition, resulting in the need to use a motor with higher power. However, the high-power motor is only used in a few cases to reflect the value of high power, which reduces the cost performance of the entire equipment.

[0039] The application provides a variable speed system which can be applied to a permanent magnet motor or a non-permanent magnet motor. The permanent magnet motor can be but is not limited to a hub motor. The variable speed system has the following aspects. In a first aspect, a spherical roller 31 is used as the transmission ratio between an input structure 10 and an output structure 20. The transmission ratio is adjusted by the precession motion of the spherical roller 31. The precession motion refers to the rotation of the axis of rotation of a rotating object caused by an external force around a certain center, also known as the spin motion. In a second aspect, the outer surface of the spherical roller 31 is continuous, and stepless speed change can be realized. In a third aspect, a centrifugal part 42 that does centrifugal motion with the actual speed of the motor is designed. The precession motion of the spherical roller 31 changes with the change of the centrifugal motion of the centrifugal part 42. When the variable speed system is applied to a motor, the transmission ratio can be automatically adjusted according to the actual output speed of the motor. In a fourth aspect, speed reduction output can be realized in a low-speed scenario to obtain higher torque. Speed increase output can be realized in a high-speed scenario to obtain higher speed at the expense of torque. When the variable speed system is applied to the wheel motor of an agricultural unmanned vehicle, the agricultural unmanned vehicle can quickly adapt to various terrains or vehicle conditions, and the performance of the motor can be fully utilized.

[0040] The application provides a hub motor which can be applied to an agricultural unmanned vehicle and can also be applied to the wheel body structure of an electric vehicle, an electric bicycle, an electric motorcycle, an electric scooter, an electric scooter, a golf cart, an intelligent inspection robot, a food delivery robot, an automatic guided vehicle and other equipment. The hub motor uses the aforementioned variable speed system. In a first aspect, the transmission ratio can be automatically adjusted. In a second aspect, the hub motor can realize the output characteristics of a larger power motor in the related art by using a smaller power motor, thereby reducing the cost of the equipment using the hub motor.

[0041] The application also provides an agricultural unmanned vehicle adopting the wheel hub motor. In a first aspect, 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 rotating speed of the motor. In a low-speed scenario, the wheel hub motor realizes speed reduction output, so as to obtain higher torque, which helps the vehicle start and escape from trouble. In a high-speed scenario, the wheel hub motor realizes speed increase output, so as to sacrifice the torque to obtain higher rotating speed, which helps the vehicle cruise at high speed. The adaptive adjustment of the transmission ratio reduces the control cost and is more intelligent without the need of a special controller or manual control of the spherical roller 31 to adjust the transmission ratio. In a second aspect, the cost performance of the whole vehicle can be improved by reducing the motor cost in the wheel hub motor vehicle.

[0042] Please continue to refer to Figures 1 to 15 , the variable speed system, the wheel hub motor and the agricultural unmanned vehicle of the application will be described below.

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

[0044] The input structure 10 is rotatably mounted on the fixing member about an input axis 100, and the output structure 20 is rotatably mounted on the fixing member about an output axis 200. In the application, the input axis 100 coincides with the output axis 200 and is horizontal.

[0045] The transmission module 30 comprises a spherical roller 31, which can rotate about a first axis 300 passing therethrough and can also rotate about a second axis 400. When the spherical roller 31 rotates about both the first axis 300 and the second axis 400, it performs a precession motion relative to the input axis 100. Figures 4 to 7 The first axis 300 is shown in the middle.

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

[0047] When the input structure 10 rotates about the input axis 100, it drives the spherical roller 31 to rotate about the first axis 300, thereby driving the output structure 20 to rotate about the output axis 200. As shown in Figure 6 、 Figure 9As shown, the position where the input structure 10 contacts the spherical roller 31 is a first position, and the vertical distance from the first position to the first axis 300 is a first distance R1; the position where the output structure 20 contacts the spherical roller 31 is a second position, and the vertical distance from the second position to the first axis 300 is a 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, at which time the spherical roller 31 rotates around the input axis 100, and the ratio of R1 to R2 changes, achieving transmission ratio adjustment.

[0048] The centrifugal mechanism includes a centrifugal piece 42, and the relative rotation between the centrifugal piece 42 and the output structure 20 around the input axis 100 is limited. With the change in the rotation speed of the output structure 20, the centrifugal piece 42 moves towards 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 change in the transmission ratio is as follows:

[0049] With the change in the actual rotation speed of the output structure 20, the centrifugal piece 42 moves towards or away from the input axis 100, so that the spherical roller 31 rotates around the second axis 400, so that the angle of the first axis 300 changes, thereby changing the ratio of R2 to R1. The transmission system of the application, the input structure 10 is driven and cooperated with the output structure 20 through the spherical roller 31, and the centrifugal mechanism is further arranged between the input structure 10 and the output structure 20, and the centrifugal mechanism includes a centrifugal piece 42. The centrifugal piece 42 rotates with 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, changes the angle of the first axis 300, changes the contact position of the transmission member with the input structure 10 and the output structure 20, changes the transmission ratio, and realizes automatic transmission. The transmission ratio can be adaptively adjusted according to the actual rotation speed of the motor, and the motor can realize speed and torque adaptation in different application scenarios, without the need for controller control or manual adjustment of the transmission ratio, reducing equipment cost and control cost.

[0050] The transmission system of the application adopts the spherical roller 31 as the spherical roller 31, and the centrifugal degree of the centrifugal piece 42 changes, the spherical roller 31 precesses, realizes stepless adjustment of the transmission ratio, and has low requirements for axial space compared with other stepless speed change designs, and is convenient to integrate into a motor module. Moreover, the spherical roller 31 precesses has the following advantages: the spherical roller 31 is a rotary body formed by rotating a circle around the first axis 300, and when the input structure 10 and the output structure 20 contact, the angle of the first axis 300 can be changed to change the values of R1 and R2, realizing stepless speed change. The transmission system of the application needs fewer parts, which is conducive to compact and small design of the transmission.

[0051] In the related art, a planetary reduction system is configured in a motor such as a wheel hub motor to achieve reduction, but the planetary reduction system is fixed transmission ratio and the transmission ratio cannot be changed. In some wheel hub motors, although the transmission system is variable transmission ratio, only one function of reduction or speed-up can be achieved, and the demand of multiple application scenarios cannot be met. In the transmission system of the present application, the degree of centrifugal member 42 thrown under the action of centrifugal force changes as the output structure 20 rotates, which can realize the movement of transmission module 30 along the radial direction in or out, i.e. the functions of reduction transmission and speed-up transmission can be achieved. Compared with the transmission system which can only achieve reduction output or speed-up output, the transmission system of the present application is easy to adapt to more application scenarios through simple and compact structure, and has high practicability.

[0052] Please continue to refer to Figures 4 to 7 In order to adapt the present transmission system to more application scenarios, the transmission system of the present application is configured to be able to reduce output and also to speed up output. The spherical roller 31 includes opposite two ends, one end of which is the inner end of the spherical roller 31, and the second end is the outer end of the spherical roller 31, and the inner end is close to the input axis 100 relative to the outer end.

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

[0054] Figures 4 to 6 In the low-speed transmission state, the spherical roller 31 is in the 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. As shown in Figure 6 R2 is less 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 high-torque scenarios, and the transmission system is applied as a reducer.

[0055] Figures 7 to 9 In the high-speed transmission state, the spherical roller 31 is in the 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. As shown in Figure 9 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 low-torque scenarios, and the transmission system is applied as a speed-up machine.

[0056] In order to facilitate understanding of the position of the spherical roller 31 in different states, refer to Figures 4 to 6, the third line 500 is inclined from outside to inside towards the direction approaching the output structure 20, and the outer end is closer to the input structure 10 than the inner end. Referring to Figures 7 to 9 , the third line 500 is inclined from outside to inside towards the direction approaching the input structure 10, and the outer end is closer to the output structure 20 than the inner end. When the spherical roller 31 is in the 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 transmission system structure more compact, the first axis 300 of the spherical roller 31 is arranged to pass through the center of the spherical roller 31, so that during the transmission process, the spherical roller 31 only rotates around the first axis 300 at the original position to realize transmission, and simultaneously rotates around the second axis 400 to adjust the angle of the first axis 300. During the transmission process, the spherical roller 31 is always at the same position in the transmission system, avoiding 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 beneficial to make the transmission more compact and smaller.

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

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

[0060] In this embodiment, by arranging the roller seat 32 and the retainer 33, the two degrees of freedom of the spherical roller 31 between the input structure 10 and the output structure 20 are decoupled into two rotational installations, so that the two degrees of freedom of rotation are realized through the cooperation of the spherical roller 31 and the roller seat 32, and the roller seat 32 and the retainer 33, respectively. On the one hand, the two degrees of freedom of rotation are more smooth, 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 arrangement of the roller seat 32, the adjustment of the angle of the roller seat 32 on the retainer 33 by the centrifugal mechanism can be realized through the cooperation of the roller seat 32 and the centrifugal mechanism, avoiding interference between the centrifugal mechanism and the spherical roller 31.

[0061] In other embodiments, a cross shaft type universal joint is arranged between the spherical roller 31 and the cage 33.

[0062] The spherical roller 31 and the roller seat 32 can be arranged in at least two ways as follows:

[0063] Arrangement 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 arranged on opposite sides of the main seat portion 321.

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

[0066] Exemplarily, the assembly of the spherical roller 31 and the main seat portion 321 can be realized by arranging the first roller portion 311 and the second roller portion 312 as a split structure, assembling the two roller portions on both sides of the main seat portion 321, and then fixing them. The assembly of the spherical roller 31 and the main seat portion 321 can also be realized by arranging the main seat portion 321 as two half seat portions, clamping the two half seat portions into the annular groove of the spherical roller 31, and then fixing them. It should be understood that the spherical roller 31 and the main seat portion 321 can also be integrally formed by some processes or assembled by other means in some embodiments.

[0067] Arrangement 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 arranged on opposite sides of the main seat portion 321. The opposite sides of the main seat portion 321 are provided with connecting shafts, 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 rotationally connected through the connecting shafts, and the first axis 300 coincides with the center line of the connecting shaft.

[0069] In the arrangement 1 and the arrangement 2, the spherical roller 31 can be rotationally mounted 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 angular adjustment of the first axis 300, and the precision is higher.

[0070] Please continue to refer to Figure 2 , the rolling seat 32 is rotationally connected with the retainer 33. The rolling seat 32 comprises second rotation shaft portions 322, and the opposite sides of the main seat portion 321 are respectively provided with the second rotation shaft portions 322. The second rotation shaft portions 322 and the main seat portion 321 can be integrally formed, and the two ends of the rolling seat 32 are rotationally connected with the retainer 33 through the second rotation shaft portions 322.

[0071] The connecting line of the two second rotation 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 position where the first axis 300 intersects with 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 the axial position of the spherical roller 31 on the retainer 33 remain unchanged when the spherical roller 31 performs the precession motion.

[0072] With respect to the second rotation shaft provided on the retainer 33, the second rotation shaft portions 322 are provided on the rolling seat 32 in the embodiment to realize the rotational connection between the rolling seat 32 and the retainer 33, and simplify the structure of the retainer 33.

[0073] Please continue to refer to Figures 1 to 3 , Figure 13 , Figure 14 In order to improve the transmission efficiency of the entire transmission system, the transmission system comprises a plurality of spherical rollers 31 and a plurality of rolling seats 32. The plurality of spherical rollers 31 and the plurality of rolling 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 roller 31 and between the output structure 20 and the spherical roller 31, so as to improve the transmission efficiency.

[0074] Please continue to refer to Figure 1 , Figure 2 , Figure 12 In order to realize the installation of the plurality of transmission modules 30, the retainer 33 is arranged with a plurality of 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 the inner groove of the installation groove 331, and the side of the retainer 33 away from the input axis 100 (i.e. the outer side of the retainer 33) forms the outer groove of the installation groove 331. The outer groove of the retainer 33 provides a clearance, so that the spherical roller 31 extends out of the installation groove 331, or the input structure 10 and the output structure 20 extend into the installation groove 331, thereby realizing the 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 at the inner side of the retainer 33, and the inner notch of the retainer 33 provides a space for the roller seat 32 to pass through the inner notch and contact the centrifugal mechanism, so that when the centrifugal member 42 of the centrifugal mechanism is in centrifugal motion, a force is applied to the roller seat 32, and the centrifugal mechanism adjusts the angle of the first axis 300 of the roller seat 32.

[0077] Through the structural design of the retainer 33, the groove wall of the mounting groove 331 of the retainer 33 can be provided on both sides of the roller seat 32 in the circumferential direction around the input axis 100, and the position of the roller seat 32 rotatingly mounted to the retainer 33 is provided 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 to the main seat portion 321 through a first shaft, and the main seat portion 321 is rotatably mounted to the groove wall of the mounting groove 331 through 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. In this embodiment, the first shaft is the connecting shaft portion 313 of the spherical roller 31, and the second shaft is the second shaft portion of the roller seat 32.

[0079] The roller seat 32 includes a main seat portion 321, the main seat portion 321 is connected to the second shaft portion on the left and right sides, 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 is applied to the roller seat 32, the roller seat 32 can rotate relative to the retainer 33 around the second axis 400. The inner extension portion 323 extends out of the inner notch of the retainer 33, and the centrifugal member 42 directly or indirectly contacts the inner extension portion 323 in at least some cases, so that when the centrifugal member 42 is in centrifugal motion, the force can be transmitted to the inner extension portion 323, the inner extension portion 323 is swung towards 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, adjusts the angle of the first axis 300, and adjusts 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 arranged between the plurality of centrifugal members 42 and the plurality of transmission modules 30. The inner extension portion 323 of the plurality of roller seats 32 is movably mounted to the linkage member 43, and the plurality of centrifugal members 42 simultaneously contact the linkage member 43. The linkage member 43 is movably arranged between the input structure 10 and the output structure 20, and the linkage member 43 is arranged to be axially movable.

[0081] The linkage 43 can be moved in the direction of the input axis 100 under the action of the centrifugal members 42 to drive the roller seat 32 to rotate around the second axis 400. When the actual rotation speed of the output structure 20 becomes large, the plurality of centrifugal members 42 are simultaneously thrown outward, the linkage 43 moves in the axial direction, and since one end of the roller seat 32 is movably mounted to the linkage 43 through the inner extension 323 and the other end is rotatably mounted to the retainer 33, when the linkage 43 moves in the axial direction, the inner extension 323 moves in the axial direction, thereby driving the roller seat 32 to rotate around the second axis 400 relative to the retainer 33 around the second axis 400, achieving angle adjustment of the first axis 300 and achieving transmission ratio adjustment.

[0082] The centrifugal force of the plurality of centrifugal members 42 uniformly acts on the linkage 43, the linkage 43 converts the centrifugal force 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 retainer 33, achieving reliable linkage of the centrifugal member 42 and the spherical roller 31. And compared with the way of one-to-one separate connection and cooperation of the centrifugal member 42 and the roller seat 32, the way of the embodiment uniformly applies the force of the plurality of centrifugal members 42 to the linkage 43, and then uniformly applies the force to the plurality of roller seats 32 through the linkage 43, so that even in the case of failure of one centrifugal member 42, the spherical roller 31 corresponding to the position can also move in linkage under the driving of the linkage 43, and the reliability is higher.

[0083] In other embodiments, the linkage 43 can not be provided, and the plurality of centrifugal members 42 and the plurality of roller seats 32 are in one-to-one abutting cooperation.

[0084] Please continue to refer to Figure 3 、 Figure 11 The linkage 43 is in the form of a ring, and the side of the linkage 43 away from the input axis 100 is provided with a clamping groove 431, and the inner extension 323 is clamped into the clamping groove 431. In this way, when the position of the linkage 43 changes in the axial direction, the inner extension 323 is pushed by the groove wall of the clamping groove 431, thereby achieving the overturning of the roller seat 32 around the second axis 400 relative to the retainer 33, which is similar to the lever motion. This assembly method can not only achieve the overturning of the roller seat 32 driven by the linkage 43 to adjust the angle of the first axis 300, but also facilitates the disassembly and assembly of the roller seat 32 and the linkage 43, which only needs to clamp or extract the inner extension 323 into or out of the clamping groove 431, without the need for tools.

[0085] It should be noted that when the inner extensions 323 of the plurality of roller seats 32 are clamped into the linkage 43 from multiple directions, the linkage 43 is movably mounted between the input structure 10 and the output structure 20, without the need for other parts to fix the linkage 43. In this way, the number of parts of the transmission system is small, the disassembly and assembly are convenient, and the structure is compact.

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

[0087] The power for the spherical roller 31 to adjust to the high-speed transmission state is provided by the centrifugal member 42. The greater the actual rotation speed of the output structure 20, the greater the degree of outward flinging of the centrifugal member 42, and the greater the degree of elastic deformation of the elastic member 50 under the action of the centrifugal member 42, the greater the degree of inclination of the third line 500 of the spherical roller 31 from outside to inside to the direction close to the output structure 20, the smaller R1, the greater R2, the ratio of R2 to R1 is greater than 1, and the smaller the transmission ratio, which is suitable for a high-speed low-torque scene.

[0088] The power for the spherical roller 31 to adjust 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 of outward flinging of the centrifugal member 42, and the smaller the force transmitted by the centrifugal member 42 to the elastic member 50, and the elastic force of the elastic member 50 can act on the roller seat 32 of the spherical roller 31 to rotate the roller seat 32 around the second axis 400, the greater the degree of inclination of the third line 500 of the spherical roller 31 from outside to inside to the direction close to the input structure 10, the greater R1, the smaller R2, the ratio of R2 to R1 is less than 1, and the greater the transmission ratio, which is suitable for a low-speed high-torque scene.

[0089] Please continue to refer to Figure 1 , Figures 4 to 7 , the elastic member 50 can be configured in the following way. The centrifugal mechanism includes 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 includes the elastic member 50; and in the direction of the input axis 100, the opposite sides of the linkage member 43 respectively contact the centrifugal member 42 and the elastic member 50.

[0090] The linkage member 43 always maintains contact with the centrifugal member 42 under the action of the elastic force of the elastic member 50, so the angular movement of the centrifugal member 42 will push the linkage member 43 to rotate the roller seat 32, thereby changing the transmission ratio. The higher the rotation speed, the greater the angular movement 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 is possible to achieve high-torque low-speed output with a large transmission ratio at low speed, and high-speed low-torque output with a small transmission ratio at high speed.

[0091] The linkage member 43 can move in the axial first direction under the action of the thrust of the centrifugal member 42, and in the present embodiment, the first direction is the direction close to the input structure 10 in the axial direction; the linkage member 43 can move in the axial second direction under the action of the elastic force of the elastic member 50, and in the present embodiment, the second direction is the direction close to the output structure 20 in the axial direction.

[0092] Please continue to refer to Figure 1 , Figures 4 to 9The elastic member 50 is arranged in the following manner. The elastic member 50 is clamped between the input structure 10 and the linkage 43. The centrifugal member 42 is hingedly connected to the output structure 20 at one end and is free at the other end, and the free end of the centrifugal member 42 abuts the side of the linkage 43 close to the output structure 20. Exemplarily, Figures 7 to 9 When the centrifugal member 42 swings outwards with a relatively large force, the free end of the centrifugal member 42 pushes the linkage 43, and at this time the elastic member 50 is continuously compressed to accumulate elastic force. Figures 4 to 6 When the centrifugal member 42 swings outwards with a relatively small force, the elastic member 50 pushes the linkage 43 downwards with elastic force.

[0093] The linkage 43 and the retainer 33 are respectively provided with limiting grooves, and the elastic member 50 is a spring, the two ends of which are respectively clamped into the limiting grooves on the two sides.

[0094] Please continue to refer to Figure 1 、 Figure 3 、 Figures 4 to 7 、 Figure 13 The centrifugal mechanism comprises a centrifugal mounting column 41 and a plurality of centrifugal members 42. The centrifugal mounting column 41 is rotationally connected to the output structure 20, and the plurality of centrifugal members 42 are arranged at intervals around the input axis 100. The centrifugal member 42 is a centrifugal swinging member, one end of which is hingedly connected to the centrifugal mounting column 41, and the other end is a free end. The centrifugal member 42 is used to push the roller seat 32 to rotate around the second axis 400 when swinging outwards.

[0095] By arranging a plurality of centrifugal members 42, when the output structure 20 rotates, the plurality of centrifugal members 42 swing outwards at different positions and uniformly act on the linkage 43 at different positions, so that the linkage 43 can stably move in the axial direction, and the feedback of the linkage 43 to the size change of the centrifugal force is more sensitive, and the angle of the first axis 300 of the spherical roller 31 can be more accurately adjusted according to the size of the centrifugal force. By arranging the centrifugal mounting column 41, the plurality of centrifugal members 42 are hingedly connected to the same centrifugal mounting column 41, which is relatively compared with a plurality of centrifugal swinging members being directly hingedly connected to different positions of the output structure 20, and the modular design of the centrifugal mechanism is realized, which is convenient for disassembly and maintenance.

[0096] In other embodiments, the centrifugal mounting column 41 can be cancelled, and several protrusions can be welded or integrally formed on the inside of the output module, and the plurality of centrifugal members 42 are hingedly connected to the protrusions on the inside of the output module.

[0097] The application also provides a wheel hub motor comprising the variable speed system.

[0098] The wheel hub motor comprises a fixing part, the input structure 10 and the output structure 20 are rotatably installed on the fixing part respectively, and the spherical roller 31 is movably installed on the fixing part.

[0099] The input structure 10 is rotatably installed on the fixing part through the first bearing, and the output structure 20 is rotatably installed on the fixing part through the second bearing.

[0100] The application also provides an agricultural unmanned vehicle, which is used for performing pesticide spraying, seeding and other operations.

[0101] In the description herein, it should be understood that the terms "upper", "lower", "left", "right", and other orientation or position relationships are based on the orientation or position relationships shown in the drawings, and are only for the convenience of description and simplification of operation, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the application. 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 the present application, the description of the terms "an embodiment", "an example" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example.

[0103] In addition, it should be understood that although the present application is described in terms of embodiments, each embodiment does not contain only one independent technical solution, and the description of the specification is only for the sake of clarity, and those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that those skilled in the art can understand.

[0104] The technical principles of the present application are described above in combination with specific embodiments. These descriptions are only for the purpose of explaining the principles of the present application, and cannot be interpreted in any way as a limitation on the scope of protection of the present application. Based on the explanation here, those skilled in the art can think of other specific embodiments of the present application without creative labor, and these embodiments will fall within the scope of protection of the present application.

Claims

1. A variable speed system characterized by, The transmission system is applied to an agricultural unmanned vehicle and comprises: an input structure (10); an output structure (20); a transmission module (30) comprising a spherical roller (31); the spherical roller (31) is rotatable about a first axis (300), and the spherical roller (31) is in drivable contact with the input structure (10) and the output structure (20); when the input structure (10) rotates about an input axis (100), the input structure (10) drives the spherical roller (31) to rotate about the first axis (300), thereby driving the output structure (20) to rotate; the distance from the position where the input structure (10) is in contact with the spherical roller (31) to the perpendicular line of the first axis (300) is R1, and the distance from the position where the output structure (20) is in contact with the spherical roller (31) to the perpendicular line of the first axis (300) is R2; a centrifugal mechanism comprising a centrifugal piece (42) arranged between the output structure (20) and the spherical roller (31); with the change of the rotating speed of the output structure (20), the centrifugal piece (42) moves towards or away from the input axis (100) to change the angle of the first axis (300), thereby changing the ratio of R2 to R1. The centrifugal mechanism comprises a centrifugal mounting column (41) and a plurality of centrifugal pieces (42); the centrifugal mounting column (41) is connected with the output structure (20), and the plurality of centrifugal pieces (42) are arranged at intervals around the input axis (100); the centrifugal piece (42) is a centrifugal swing piece, one end of the centrifugal piece (42) is hinged to the centrifugal mounting column (41), and the other end is a free end.

2. The transmission system of claim 1, wherein, The spherical roller (31) is movably mounted between the input structure (10) and the output structure (20); the spherical roller (31) is configured to be rotatable about the first axis (300) and rotatable about a second axis (400); When the centrifugal piece (42) moves towards or away from the input axis (100), the spherical roller (31) rotates about the second axis (400) to change the angle of the first axis (300).

3. The transmission system of claim 2, wherein, 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, R2 is less than R1; when the spherical roller (31) is in the high-speed transmission state, R2 is greater than R1.

4. The transmission system of claim 2, wherein, The transmission module (30) comprises a roller seat (32) and a retainer (33); The spherical roller (31) is rotatably mounted on the roller seat (32), and the spherical roller (31) is rotatable about the first axis (300) relative to the roller seat (32); the roller seat (32) is rotatably mounted on the retainer (33), and the roller seat (32) is rotatable about the second axis (400) relative to the retainer (33).

5. The transmission system of claim 4, wherein, 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 axle hole (3211), and the spherical roller (31) comprises a connecting axle portion (313) arranged in the axle hole (3211), and the first roller portion (311), the connecting axle portion (313) and the second roller portion (312) are sequentially connected along the first axis (300); or, connecting axles are arranged 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 rotationally connected through the connecting axles, and the first axis (300) coincides with the center line of the connecting axles.

6. The transmission system according to any one of claims 4 to 5, characterized in that, The roller seat (32) comprises a main seat portion (321), and a second rotating shaft portion (322) arranged on opposite sides of the main seat portion (321); The spherical roller (31) is rotationally mounted on the main seat portion (321); and the second rotating shaft portion (322) on each side of the roller seat (32) is rotationally connected with the retainer (33).

7. The transmission system of claim 4, wherein, The variable speed system comprises a plurality of the spherical rollers (31) and a plurality of the roller seats (32); and the plurality of the spherical rollers (31) and the plurality of the roller seats (32) are arranged at intervals around the input axis (100).

8. The transmission system of claim 7, wherein, The retainer (33) comprises a plurality of mounting grooves (331) arranged at intervals around the input axis (100); The side of the retainer (33) close to the input axis (100) forms an inner groove opening of the mounting groove (331), and the side away from the input axis (100) forms an outer groove opening of the mounting groove (331); The centrifugal mechanism is arranged on the inner side of the retainer (33), and the roller seat (32) or the spherical roller (31) is in position with the centrifugal mechanism through the inner groove opening; and the spherical roller (31) is in contact with the input structure (10) and the output structure (20) through the outer groove opening.

9. The transmission system of claim 8, wherein, The roller seat (32) comprises a main seat portion (321), and the spherical roller (31) is rotationally mounted on the main seat portion (321) through a first shaft, and the main seat portion (321) is rotationally mounted on the groove wall of the mounting groove (331) through 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 inner extension portion (323) connected with the main seat portion (321), and the centrifugal member (42) acts on the inner extension portion (323) to drive the roller seat (32) to rotate the spherical roller (31) around the second axis (400).

10. The transmission system of claim 9, wherein, The centrifugal mechanism comprises a linkage (43), inner extensions (323) of a plurality of the roller seats (32) are movably mounted to the linkage (43); the centrifugal member (42) is in contact with the linkage (43).

11. The transmission system of claim 10, wherein, The linkage (43) is annular in structure, a clamping groove (431) is arranged on a side of the linkage (43) away from the input axis (100), and the inner extension (323) is clamped into the clamping groove (431); the linkage (43) is movably mounted between the input structure (10) and the output structure (20). The linkage (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 transmission system of claim 11, wherein, The centrifugal mechanism comprises a plurality of the centrifugal members (42), the plurality of the 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 (43). The linkage (43) can move in an axial first direction under the action of the thrust of the centrifugal member (42); the linkage (43) can move in an axial second direction under the action of the elastic force of the elastic member (50).

13. The transmission system of claim 12, wherein, The elastic member (50) is clamped between the linkage (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; the free end of the centrifugal member (42) abuts against a side of the linkage (43) close to the output structure (20).

14. The transmission system of claim 7, wherein, The centrifugal member (42) is used to push the roller seat (32) to rotate around the second axis (400) when the centrifugal member (42) swings.

15. A wheel hub motor, characterized by The variable speed system comprises the hub motor as claimed in any one of claims 1-14; the hub motor comprises a fixing member, the input structure (10) and the output structure (20) are respectively rotatably mounted to the fixing member; the spherical roller (31) is movably mounted to the fixing member.

16. An agricultural unmanned vehicle, characterized by The hub motor comprises the variable speed system as claimed in claim 15.

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