Redundant multi-power driving system based on differential rotating speed coupling

Abstract

The invention belongs to the technical field of spacecraft power systems, and particularly relates to a redundant multi-power driving system based on differential rotation speed coupling. Comprising a shell, and a driving motor I, an electromagnetic brake I, a differential rotating speed coupling device, an electromagnetic brake II, a driving motor II and a secondary reduction gear which are arranged in the shell, wherein output shafts of the driving motor I and the driving motor II are respectively connected with two input shafts of the differential rotating speed coupling device; the front ends of the driving motor I and the driving motor II are respectively provided with an electromagnetic brake I and an electromagnetic brake II which are used for braking the output shaft; an output shaft of the differential rotating speed coupling device is connected with an input shaft of the second-stage speed reduction device, and the differential rotating speed coupling device can achieve single-motor power output or double-motor coupling power output to the second-stage speed reduction device. The energy loss in the transmission system is effectively reduced, the transmission efficiency of the system is improved, and the manned lunar rover can still run safely even if part of motors break down.

Description

Technical Field

[0001] The invention belongs to the technical field of spacecraft power systems, and in particular relates to a redundant multi-power drive system based on differential speed coupling. Background Art

[0002] Manned lunar rover is an important part of manned lunar landing and an important tool for astronauts to explore, sample, conduct scientific experiments and other activities on the lunar surface. Existing manned lunar rovers generally use four-wheel motor drive. This method can effectively reduce the volume and mass of the transmission system and improve the driving efficiency by integrating electric motors in the wheels. However, the four-wheel motor drive system also has certain risks. Motor failure will lead to the loss of power of the corresponding wheels, which is easy to cause the vehicle to fall or skid under soft lunar soil or steep slope conditions; the probability of simultaneous failure of multiple motors increases significantly under extreme conditions such as motor overheating, lunar dust intrusion, and meteorite impact; the energy consumption of the four motors is too large when running at full power, which limits the continuous operation time on the lunar surface. Due to the complex driving environment of the lunar rover, if a motor failure occurs, the driving ability and safety of the entire vehicle will be seriously affected. Therefore, there is an urgent need for a spacecraft power system that can ensure that the manned lunar rover can still drive safely even when some motors fail. Summary of the invention

[0003] In view of the above problems, the purpose of the present invention is to provide a redundant multi-power drive system based on differential speed coupling to solve the problem that motor failure may occur in the existing four-wheel drive motor system and cause the whole vehicle to be unable to drive.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions: The present invention provides a redundant multi-power drive system based on differential speed coupling, comprising a housing and a drive motor I, an electromagnetic brake I, a differential speed coupling device, an electromagnetic brake II, a drive motor II and a secondary reduction device installed in the housing, wherein a drive motor output shaft I of the drive motor I is connected to an input shaft of the differential speed coupling device, a drive motor output shaft II of the drive motor II is connected to another input shaft of the differential speed coupling device, and the front ends of the drive motors I and II are respectively provided with electromagnetic brakes I and electromagnetic brakes II for braking the output shafts; The output shaft of the differential speed coupling device is connected to the input shaft of the secondary reduction device, and the differential speed coupling device can realize single-motor power output or dual-motor coupled power output to the secondary reduction device.

[0005] The differential speed coupling device comprises a coupling device housing, an input bevel gear shaft, a driven bevel gear, a planetary gear assembly I and two half-shaft bevel gears I, wherein the input bevel gear shaft is connected to the output shaft I of the drive motor, the coupling device housing is rotationally connected to the housing, the driven bevel gear is fixedly arranged on the outside of the coupling device housing, and the driven bevel gear is meshed with the input bevel gear shaft, and the drive motor I provides power for the rotation of the coupling device housing; The planetary gear assembly I is arranged in the coupling device housing, and the two half-shaft bevel gears I are rotatably installed in the coupling device housing, and the rotation axes are collinear; the two half-shaft bevel gears I are respectively located on both sides of the planetary gear assembly I and are both meshed with the planetary gear assembly I; the two half-shaft bevel gears I are respectively connected to the output shaft II of the drive motor and the input shaft of the secondary reduction device.

[0006] The planetary gear assembly I includes a planetary gear shaft I and two planetary gears I, wherein the planetary gear shaft I is fixed in the coupling device housing, and the axis of the planetary gear shaft I is perpendicular to the axis of the half-shaft bevel gear I; the two planetary gears I are rotatably mounted on both ends of the planetary gear shaft I through needle bearings, and the backs of the two planetary gears I are connected to the coupling device housing through thrust ball bearings I; the two planetary gears I are meshed with the half-shaft bevel gears I on both sides.

[0007] The secondary reduction device comprises a secondary reduction device output shaft I, a secondary reduction device output shaft II, an input gear shaft, an intermediate gear shaft, a driven helical gear, a differential housing and a differential planetary gear mechanism, wherein the input gear shaft, the intermediate gear shaft and the driven helical gear are rotatably mounted on the housing and meshed in sequence, and the input gear shaft is connected to the output shaft of the differential speed coupling device; the driven helical gear is fixedly mounted on the differential housing, and the differential housing is rotatably connected to the housing, and the secondary reduction device output shaft I and the secondary reduction device output shaft II are rotatably mounted on both sides of the differential housing, and the axes are collinear; The differential planetary gear mechanism is arranged in the differential housing, and the differential planetary gear mechanism is connected to the secondary reduction device output shaft I and the secondary reduction device output shaft II, and the differential planetary gear mechanism is used to distribute power to the secondary reduction device output shaft I and the secondary reduction device output shaft II.

[0008] The differential planetary gear mechanism includes a planetary gear assembly II and two half-shaft bevel gears II, wherein the planetary gear assembly II is arranged in the differential housing, and the two half-shaft bevel gears II are rotatably installed on both sides of the differential housing, and the rotation axes are collinear; the two half-shaft bevel gears II are both meshed with the planetary gear assembly II, and the two half-shaft bevel gears II are coaxially connected to the secondary reduction device output shaft I and the secondary reduction device output shaft II, respectively.

[0009] The planetary gear assembly II includes a planetary gear shaft II and two planetary gears II rotatably mounted at both ends of the planetary gear shaft II. Planetary gear gaskets are provided on the backs of the two planetary gears II. Each planetary gear II is meshed with the half-shaft bevel gears II on both sides.

[0010] The electromagnetic brake I and the electromagnetic brake II have the same structure, and both include a brake housing and an elastic guide assembly, an electromagnet, an armature and a brake disc installed in the brake housing, wherein the brake housing is rotatably installed on the output shaft I of the drive motor or the output shaft II of the drive motor, and the brake housing is fixedly connected to the housing; the brake disc is connected to the output shaft I of the drive motor or the output shaft II of the drive motor through a spline shaft; The electromagnet is embedded in the inner side of the brake housing, the armature is arranged between the electromagnet and the brake disc, and the armature is connected to the brake housing through an elastic guide component; when the electromagnet is energized, the armature is adsorbed to the electromagnet; when the electromagnet is de-energized, the elastic guide component pushes the armature to fit the brake disc to achieve braking.

[0011] The elastic guide assembly includes a plurality of armature guide shafts and a plurality of springs which are circumferentially arranged on the inner side of the brake housing, wherein the plurality of armature guide shafts are located on the inner side of the electromagnet, the armature slides with the plurality of armature guide shafts, and the plurality of springs are located on the outer side of the electromagnet and abut against the armature.

[0012] The brake disc includes a friction plate and a brake disc body, wherein the brake disc body is key-connected to the drive motor output shaft I or the drive motor output shaft II, and the brake disc body is rotationally connected to the housing of the drive motor I or the drive motor II through a thrust ball bearing II, and the friction plate is fixed on the front end surface of the brake disc body.

[0013] An adjusting gasket is provided between the brake housing and the housing of the drive motor I or the drive motor II.

[0014] The advantages and beneficial effects of the present invention are as follows: the redundant multi-power drive system based on differential speed coupling provided by the present invention solves the problem that the existing four-wheel motor drive system cannot provide redundant power when the motor fails by adopting the differential speed coupling design, thereby ensuring the continuous driving capability of the manned lunar rover; through the cooperation of the electromagnetic brake, measures can be taken quickly when the motor fails to prevent the faulty motor from having adverse effects on the entire vehicle. In addition, the system not only improves the stability and efficiency of power transmission through the combination of speed coupling and a secondary reduction device, but also realizes stepless speed control, so that the lunar rover can flexibly respond to various driving needs in complex terrain. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1It is a structural schematic diagram of a redundant multi-power drive system based on differential speed coupling of the present invention; Figure 2 It is a structural schematic diagram of the differential speed coupling device in the present invention; Figure 3 It is a schematic diagram of an explosion of the electromagnetic brake in the present invention; Figure 4 is a cross-sectional view of the electromagnetic brake of the present invention; Figure 5 It is a schematic structural diagram of the two-stage reduction device in the present invention.

[0016] In the figure: 1-driving motor Ⅰ, 11-motor housing Ⅰ, 12-bolt Ⅰ, 2-electromagnetic brake Ⅰ, 21-driving motor output shaft Ⅰ, 22-coupling, 23-tapered roller bearing Ⅰ, 3-differential speed coupling device, 31-deep groove ball bearing Ⅰ, 32-coupling device housing, 331-tapered roller bearing Ⅱ, 332-input bevel gear shaft, 341-driven bevel gear, 342-bolt Ⅱ, 35-planetary gear assembly Ⅰ, 351-planetary gear Ⅰ, 352-thrust Ball bearing Ⅰ, 353-planetary gear shaft Ⅰ, 354-needle bearing, 361-semi-axle gear tapered roller bearing, 362-semi-axle bevel gear Ⅰ, 371-bearing fixing sleeve, 372-bolt Ⅲ, 4-housing, 41-hexagon head screw Ⅰ, 42-hexagon head screw Ⅱ, 43-housing end cover, 5-deep groove ball bearing Ⅱ, 51-bearing pressure cover, 6-electromagnetic brake Ⅱ, 61-drive motor output shaft Ⅱ, 62-brake housing, 63-armature guide shaft, 64-electromagnet, 6 5-spring, 66-armature, 67-brake disc, 671-friction plate, 672-brake disc body, 673-rivet, 68-adjusting gasket, 69-thrust ball bearing II, 7-drive motor II, 71-bolt VI, 72-motor housing II, 8-coupling device mounting bracket, 81-deep groove ball bearing III, 82-housing connector, 9-secondary reduction device, 91-secondary reduction device output shaft I, 92-secondary reduction device output shaft II, 931-bearing end cover I, 932-screw Bolt V, 941-tapered roller bearing III, 942-input gear shaft, 943-deep groove ball bearing VI, 944-intermediate gear shaft, 951-bolt IV, 952-bearing end cover II, 953-tapered roller bearing VI, 961-anti-friction gasket, 962-semi-shaft bevel gear II, 971-driven helical gear, 972-bolt VII, 98-planetary gear assembly II, 981-planetary gear shaft II, 982-planetary gear II, 983-planetary gear gasket, 99-differential case. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0018] See also Figures 1 to 5 As shown, the present invention provides a redundant multi-power drive system based on differential speed coupling, including a housing 4 and a drive motor Ⅰ1, an electromagnetic brake Ⅰ2, a differential speed coupling device 3, an electromagnetic brake Ⅱ6, a drive motor Ⅱ7 and a secondary reduction device 9 installed in the housing 4, wherein the drive motor output shaft Ⅰ21 of the drive motor Ⅰ1 is connected to an input shaft of the differential speed coupling device 3, and a motor housing Ⅰ11 is provided on the outside of the drive motor Ⅰ1. The drive motor output shaft Ⅱ61 of the drive motor Ⅱ7 is connected to the other input shaft of the differential speed coupling device 3, and the drive motor output shaft Ⅱ61 is connected to the housing 4 through a deep groove ball bearing Ⅱ5, and the deep groove ball bearing Ⅱ5 is axially limited by a bearing gland 51, and a motor housing Ⅱ72 is provided on the outside of the drive motor Ⅱ7. The front ends of the drive motor Ⅰ1 and the drive motor Ⅱ7 are respectively provided with electromagnetic brakes Ⅰ2 and electromagnetic brakes Ⅱ6 for braking the output shafts, and the electromagnetic brake Ⅰ2 is connected to the motor housing Ⅰ11 through bolts Ⅰ12, and the electromagnetic brake Ⅱ6 is connected to the motor housing Ⅱ72 through bolts Ⅵ71. The output shaft of the differential speed coupling device 3 is connected to the input shaft of the secondary reduction device 9 , and the differential speed coupling device 3 can realize single-motor power output or dual-motor coupled power output to the secondary reduction device 9 .

[0019] See also Figure 2 As shown, in the embodiment of the present invention, the differential speed coupling device 3 includes a coupling device housing 32, an input bevel gear shaft 332, a driven bevel gear 341, a planetary gear assembly I35 and two half-shaft bevel gears I362, wherein the input bevel gear shaft 332 is connected to the output shaft I21 of the driving motor through the coupling 22, and the coupling 22 and the input bevel gear shaft 332 are rotatably connected to the housing 4 through the tapered roller bearing I23 and the tapered roller bearing II331 respectively; deep groove ball bearings I31 are provided at both ends of the coupling device housing 32, and a bearing fixing sleeve 371 is provided on the outer side of the deep groove ball bearing I31, and the bearing fixing sleeve 371 is fixedly connected to the housing 4 through bolts III372, and the coupling device housing 32 can rotate relative to the housing 4. The driven bevel gear 341 is fixed to the outer end of the coupling device housing 32 by bolts II 342, and the driven bevel gear 341 is meshed with the input bevel gear shaft 332, and the driving motor I1 provides power for the rotation of the coupling device housing 32; the planetary gear assembly I35 is arranged in the coupling device housing 32, and the two half-shaft bevel gears I362 are rotatably installed in the coupling device housing 32 through the half-shaft gear tapered roller bearings 361, and the rotation axes are collinear; the two half-shaft bevel gears I362 are respectively located on both sides of the planetary gear assembly I35 and are both meshed with the planetary gear assembly I35; the two half-shaft bevel gears I362 are respectively connected to the output shaft II61 of the driving motor and the input shaft of the secondary reduction device 9.

[0020] See also Figure 2As shown, in the embodiment of the present invention, the planetary gear assembly Ⅰ35 includes a planetary gear shaft Ⅰ353 and two planetary gears Ⅰ351, wherein the planetary gear shaft Ⅰ353 is fixed in the coupling device housing 32, and the axis of the planetary gear shaft Ⅰ353 is perpendicular to the axis of the half-shaft bevel gear Ⅰ362; the two planetary gears Ⅰ351 are rotatably mounted on both ends of the planetary gear shaft Ⅰ353 through needle bearings 354, and the backs of the two planetary gears Ⅰ351 are connected to the coupling device housing 32 through thrust ball bearings Ⅰ352; the two planetary gears Ⅰ351 are meshed with the half-shaft bevel gears Ⅰ362 on both sides.

[0021] Specifically, the thrust ball bearing I352 of the planetary gear I351 is used to bear the axial force, and convert the sliding friction between the planetary gear I351 and the coupling device housing 32 into rolling friction; the needle bearing 354 is used to bear the radial force, and convert the sliding friction between the planetary gear I351 and the planetary gear shaft I353 into rolling friction. The half-shaft bevel gear I362 rotates with the spline shaft under the drive of the spline shaft, and will rub against the housing under the action of the axial force. Therefore, the half-shaft gear tapered roller bearing 361 is installed at the contact point between the half-shaft bevel gear I362 and the coupling device housing 32, which can not only support the spline shaft but also convert the sliding friction into rolling friction.

[0022] The planetary gear shaft of the traditional differential is a smooth shaft, and sliding friction will occur when the planetary gear rotates relative to the shaft. In order to avoid severe friction under the influence of the speed difference, the present invention installs a K-type needle roller bearing 354 on the planetary gear shaft I 353. The needle roller bearing 354 has a small radial size and a simple structure, and can be directly installed on the planetary gear shaft I 353.

[0023] Specifically, the coupling housing 32 is made of high-strength cast iron, and the overall structure is a complex geometric shape. Precision mounting seats and bearing cavities are set inside to accommodate the internal gears and bearings, which is convenient for assembly and maintenance. Reinforcement ribs are designed at key locations, and the surface is treated with corrosion-resistant coating to increase service life. Heat dissipation requirements are taken into account during the design process to ensure that the differential works normally under high load and high temperature conditions.

[0024] In an embodiment of the present invention, the differential speed coupling device 3 is used to smoothly couple the driving speeds of the drive motor I1 and the drive motor II7, so that the output speeds of the drive motor I1 and the drive motor II7 are linearly superimposed as needed. Considering the compactness and stability of the structure, the input bevel gear shaft 332 adopts a cantilever double-bearing fixed support. The differential speed coupling device 3 can not only accurately synchronize the speeds of the two drive motors, but also has an efficient energy transfer function, reduces energy loss, and improves the efficiency of the overall system. Due to the speed coupling characteristics of the differential, the lunar rover can intelligently switch the working mode according to actual needs under different driving conditions to achieve efficient power output.

[0025] See also Figure 5 As shown, in the embodiment of the present invention, the two-stage reduction device 9 includes a two-stage reduction device output shaft I 91, a two-stage reduction device output shaft II 92, an input gear shaft 942, an intermediate gear shaft 944, a driven bevel gear 971, a differential housing 99 and a differential planetary gear mechanism, wherein the input gear shaft 942, the intermediate gear shaft 944 and the driven bevel gear 971 are rotatably mounted on the housing 4 and meshed in sequence, the input gear shaft 942 is connected to the half-shaft bevel gear I 362 of the differential speed coupling device 3, and the intermediate gear shaft 944 is used to connect and transmit power to the half-shaft gears. The driven bevel gear 971 is fixedly mounted on the outer end of the differential housing 99 by bolts VII 972. The differential housing 99 is rotationally connected to the housing 4. The secondary reduction device output shaft I91 and the secondary reduction device output shaft II 92 are rotationally mounted on both sides of the differential housing 99 by tapered roller bearings VI 953, and the axes are collinear. The differential planetary gear mechanism is arranged in the differential housing 99. The differential planetary gear mechanism is connected to the secondary reduction device output shaft I91 and the secondary reduction device output shaft II 92. The differential planetary gear mechanism is used to distribute power to the secondary reduction device output shaft I91 and the secondary reduction device output shaft II 92.

[0026] See also Figure 5 As shown, in the embodiment of the present invention, the differential planetary gear mechanism includes a planetary gear assembly II98 and two half-shaft bevel gears II962, wherein the planetary gear assembly II98 is arranged in the differential housing 99, and the two half-shaft bevel gears II962 are rotatably mounted on both sides of the differential housing 99, and the rotation axes are collinear; the two half-shaft bevel gears II962 are both meshed with the planetary gear assembly II98, and the two half-shaft bevel gears II962 are coaxially connected to the secondary reduction device output shaft I91 and the secondary reduction device output shaft II92, respectively. Further, the backs of the two half-shaft bevel gears II962 are provided with anti-friction washers 961, and the anti-friction washers 961 are used to reduce the friction between the half-shaft bevel gears II962 and the differential housing 99, and the ends of the secondary reduction device output shaft I91 and the secondary reduction device output shaft II92 are both internal splines.

[0027] In an embodiment of the present invention, the planetary gear assembly II98 includes a planetary gear shaft II981 and two planetary gears II982 rotatably mounted at both ends of the planetary gear shaft II981, and planetary gear gaskets 983 are provided on the backs of the two planetary gears II982; each planetary gear II982 is meshed with the half-shaft bevel gears II962 on both sides.

[0028] Furthermore, the two ends of the secondary reduction device 9 are respectively provided with a bearing end cover I931 and a bearing end cover II952, the bearing end cover I931 is connected to the housing 4 through a bolt V932, and the bearing end cover II952 is connected to the housing 4 through a bolt IV951. The input gear shaft 942 is connected to the bearing end cover I931 through a tapered roller bearing III941, and the two ends of the intermediate gear shaft 944 are respectively connected to the bearing end cover I931 and the bearing end cover II952 through a deep groove ball bearing VI943.

[0029] Furthermore, the housing 4 is arranged on two coupling device mounting frames 8, and the secondary reduction device output shaft I 91 and the secondary reduction device output shaft II 92 are rotatably connected to the two coupling device mounting frames 8 through deep groove ball bearings III 81. A housing end cover 43 is provided on the side of the housing 4 opposite to the drive motor I, and the housing end cover 43 is connected to the housing 4 through a hexagon head screw II 42, and a housing connector 82 is provided on the side wall of the housing 4.

[0030] In the embodiment of the present invention, the secondary reduction device 9 adopts a helical gear reduction mechanism to ensure smooth power transmission and efficient power conversion, play the role of reducing speed and increasing torque, and reasonably distribute the torque from the drive motor I1 and the drive motor II7 to the left and right wheels; the differential planetary gear mechanism evenly distributes power through the coordinated work of the planetary gear II 982 and the half-shaft bevel gear II 962, ensuring that the vehicle maintains stable driving under turning or different load conditions.

[0031] See also Figure 3 and Figure 4 As shown, in the embodiment of the present invention, the electromagnetic brake I2 and the electromagnetic brake II6 have the same structure, both of which include a brake housing 62 and an elastic guide assembly, an electromagnet 64, an armature 66 and a brake disc 67 installed in the brake housing 62, wherein the brake housing 62 is rotatably installed on the drive motor output shaft I21 or the drive motor output shaft II61 through a deep groove ball bearing II5, and one end of the brake housing 62 is fixedly connected to the housing of the drive motor I1 or the drive motor II7 by a bolt VI71, and an adjustment gasket 68 is provided between the brake housing 62 and the housing of the drive motor I1 or the drive motor II7, and the adjustment gasket 68 is used to adjust the gap between the drive motor II7 and the brake housing 62, and is fixed by a bolt VI71. The other end of the brake housing 62 is connected to the housing 4 by a hexagon head screw I41. The brake disc 67 is fixed on the drive motor output shaft Ⅰ21 or the drive motor output shaft Ⅱ61 through a spline shaft; the electromagnet 64 is embedded in the inner side of the brake housing 62, the armature 66 is arranged between the electromagnet 64 and the brake disc 67, and the armature 66 is connected to the brake housing 62 through an elastic guide component; when the electromagnet 64 is energized, the armature 66 is adsorbed on the electromagnet 64; when the electromagnet 64 is de-energized, the elastic guide component pushes the armature 66 to fit the brake disc 67 to achieve braking.

[0032] Specifically, the elastic guide assembly includes a plurality of armature guide shafts 63 and a plurality of springs 65 which are circumferentially arranged on the inner side of the brake housing 62, wherein the plurality of armature guide shafts 63 are located on the inner side of the electromagnet 64, the armature 66 slides with the plurality of armature guide shafts 63 through guide holes, and the plurality of springs 65 are located on the outer side of the electromagnet 64 and abut against the armature 66, and the springs 65 can push the armature 66 to move axially.

[0033] In an embodiment of the present invention, the brake disc 67 includes a friction plate 671 and a brake disc body 672, wherein the brake disc body 672 is key-connected to the drive motor output shaft Ⅰ21 or the drive motor output shaft Ⅱ61, and the back of the brake disc body 672 is rotatably connected to the housing of the drive motor Ⅰ1 or the drive motor Ⅱ7 through a thrust ball bearing Ⅱ69, and the friction plate 671 is fixed to the front end face of the brake disc body 672 by a rivet 673.

[0034] Specifically, the electromagnetic brake is used to quickly apply braking force when a motor fails, so that the faulty motor stops rotating, thereby ensuring that the other motor can continue to provide power. The brake housing 62 is used to protect the internal components and provide structural support, and has sealing properties to prevent dust and impurities from entering the interior. The electromagnet 64 is one of the key components. Its internal coil is wound with insulated copper wire. When the coil is energized, a magnetic field is generated to attract the armature 66 to release the brake. The movable part of the armature 66 is made of soft magnetic material, and the contact with the brake disc 67 is a high friction flange located near the electromagnetic coil. When power is turned on, the magnetic force generated by the electromagnetic coil attracts the armature 66, and the armature 66 overcomes the spring force and moves, thereby releasing the brake. The function of the spring 65 is to provide a reaction force when the power is off, push the armature 66 back to the initial position, compress the brake disc 67, and generate braking force. The brake disc 67 is fixed to the motor output shaft through a spline, and the friction plate 671 needs to have a high friction coefficient and wear resistance, and is made of synthetic materials to generate friction to achieve braking.

[0035] Working principle of electromagnetic brake Ⅰ2 and electromagnetic brake Ⅱ6: When the coil of the electromagnet 64 is energized, the electromagnet 64 generates an electromagnetic force to attract the armature 66, and the armature 66 approaches the brake housing 62 through the armature guide shaft 63. When the coil of the electromagnet 64 loses power, the armature 66 is pushed toward the brake disc 67 by the spring 65 installed in the brake housing 62, and rubs against the friction plate 671 on the brake disc 67 to generate a braking force, thereby limiting the rotation of the motor output shaft. The generated axial braking force is first transmitted to the motor through the thrust ball bearing and then to the housing. The power distributor input shaft is connected to the motor shaft through the spline on the brake disc, and the deep groove ball bearing is used to support one end of the power distributor input shaft. Through this design, even if the motor fails, the electromagnetic brake can quickly take effect to ensure the safety and driving ability of the vehicle.

[0036] The present invention provides a redundant multi-power drive system based on differential speed coupling, in which both drive motors are high-efficiency permanent magnet synchronous motors of the same power, suitable for the power requirements of the lunar rover, and can be speed-coupled through a coupling device. The working state of the drive motor is adjusted in real time through the differential speed coupling device 3 to ensure the stability of power transmission.

[0037] During the power coupling process of the differential speed coupling device 3 of the present invention, the torques of the two power sources are in a certain proportional relationship with each other, the output speeds are independent of each other, and the final output synthetic speed is the linear superposition of the speeds of the two power sources. When the speed of one power source changes, the speed of the other power source will also change accordingly. Therefore, it is only necessary to fix the speed of one of the drive motors and adjust the speed of the other drive motor to achieve stepless speed change, automatically adjust the vehicle speed under different terrains, and improve sports performance.

[0038] When one of the drive motors cannot be used due to a fault, the electromagnetic brake is activated to lock the corresponding output shaft, limiting the rotation of the output shaft. The other drive motor works alone to transmit power to the wheels through the differential speed coupling device 3 and the secondary reduction device 9, thereby realizing single-motor drive.

[0039] The present invention provides a redundant multi-power drive system based on differential speed coupling. The differential speed coupling device 3 realizes speed coupling and power distribution, has single motor fault tolerance, ensures that the manned lunar rover can still drive safely even when some motors fail, and significantly improves driving safety and passability under complex lunar terrain. The present invention can effectively reduce energy loss in the transmission system, improve the transmission efficiency of the system, and ensure that the lunar rover has stronger adaptability under different terrain conditions.

[0040] The above description is only an embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, expansion, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A redundant multi-power drive system based on differential speed coupling, characterized in that: The invention comprises a housing (4), a drive motor I (1), an electromagnetic brake I (2), a differential speed coupling device (3), an electromagnetic brake II (6), a drive motor II (7) and a two-stage reduction device (9) installed in the housing (4), wherein a drive motor output shaft I (21) of the drive motor I (1) is connected to an input shaft of the differential speed coupling device (3), a drive motor output shaft II (61) of the drive motor II (7) is connected to another input shaft of the differential speed coupling device (3), and the front ends of the drive motor I (1) and the drive motor II (7) are respectively provided with an electromagnetic brake I (2) and an electromagnetic brake II (6) for braking the output shafts; The output shaft of the differential speed coupling device (3) is connected to the input shaft of the secondary reduction device (9), and the differential speed coupling device (3) can realize single-motor power output or dual-motor coupled power output to the secondary reduction device (9).

2. The redundant multi-power drive system based on differential speed coupling according to claim 1, characterized in that: The differential speed coupling device (3) comprises a coupling device housing (32), an input bevel gear shaft (332), a driven bevel gear (341), a planetary gear assembly I (35) and two half-shaft bevel gears I (362), wherein the input bevel gear shaft (332) is connected to the output shaft I (21) of the drive motor, the coupling device housing (32) is rotationally connected to the housing (4), the driven bevel gear (341) is fixedly arranged on the outside of the coupling device housing (32), and the driven bevel gear (341) is meshed with the input bevel gear shaft (332), and the drive motor I (1) provides power for the rotation of the coupling device housing (32); The planetary gear assembly I (35) is arranged in a coupling device housing (32); the two half-shaft bevel gears I (362) are rotatably mounted in the coupling device housing (32) with their rotation axes collinear; the two half-shaft bevel gears I (362) are respectively located on both sides of the planetary gear assembly I (35) and are both meshed with the planetary gear assembly I (35); the two half-shaft bevel gears I (362) are respectively connected to the output shaft II (61) of the drive motor and the input shaft of the secondary reduction device (9).

3. The redundant multi-power drive system based on differential speed coupling according to claim 2, characterized in that: The planetary gear assembly I (35) comprises a planetary gear shaft I (353) and two planetary gears I (351), wherein the planetary gear shaft I (353) is fixed in the coupling device housing (32), and the axis of the planetary gear shaft I (353) is perpendicular to the axis of the half-shaft bevel gear I (362); the two planetary gears I (351) are rotatably mounted on both ends of the planetary gear shaft I (353) via needle bearings (354), and the backs of the two planetary gears I (351) are connected to the coupling device housing (32) via thrust ball bearings I (352); and the two planetary gears I (351) are meshed with the half-shaft bevel gears I (362) on both sides.

4. The redundant multi-power drive system based on differential speed coupling according to claim 1, characterized in that: The secondary reduction device (9) comprises a secondary reduction device output shaft I (91), a secondary reduction device output shaft II (92), an input gear shaft (942), an intermediate gear shaft (944), a driven helical gear (971), a differential housing (99) and a differential planetary gear mechanism, wherein the input gear shaft (942), the intermediate gear shaft (944) and the driven helical gear (971) are rotatably mounted on the housing (4) and meshed in sequence, the input gear shaft (942) is connected to the output shaft of the differential speed coupling device (3); the driven helical gear (971) is fixedly mounted on the differential housing (99), the differential housing (99) is rotatably connected to the housing (4), and the secondary reduction device output shaft I (91) and the secondary reduction device output shaft II (92) are rotatably mounted on both sides of the differential housing (99), with their axes being collinear; The differential planetary gear mechanism is arranged in the differential housing (99), and the differential planetary gear mechanism is connected to the secondary reduction device output shaft I (91) and the secondary reduction device output shaft II (92), and the differential planetary gear mechanism is used to distribute power to the secondary reduction device output shaft I (91) and the secondary reduction device output shaft II (92).

5. The redundant multi-power drive system based on differential speed coupling according to claim 4, characterized in that: The differential planetary gear mechanism comprises a planetary gear assembly II (98) and two half-shaft bevel gears II (962), wherein the planetary gear assembly II (98) is arranged in the differential housing (99), and the two half-shaft bevel gears II (962) are rotatably mounted on both sides of the differential housing (99), and the rotation axes are collinear; the two half-shaft bevel gears II (962) are both meshed with the planetary gear assembly II (98), and the two half-shaft bevel gears II (962) are coaxially connected to the secondary reduction device output shaft I (91) and the secondary reduction device output shaft II (92), respectively.

6. The redundant multi-power drive system based on differential speed coupling according to claim 5, characterized in that: The planetary gear assembly II (98) comprises a planetary gear shaft II (981) and two planetary gears II (982) rotatably mounted at both ends of the planetary gear shaft II (981), and planetary gear gaskets (983) are provided on the backs of the two planetary gears II (982); each planetary gear II (982) is meshed with the half-shaft bevel gears II (962) on both sides.

7. The redundant multi-power drive system based on differential speed coupling according to claim 1, characterized in that: The electromagnetic brake I (2) and the electromagnetic brake II (6) have the same structure, and both include a brake housing (62) and an elastic guide assembly, an electromagnet (64), an armature (66) and a brake disc (67) installed in the brake housing (62), wherein the brake housing (62) is rotatably mounted on the output shaft I (21) of the drive motor or the output shaft II (61) of the drive motor, and the brake housing (62) is fixedly connected to the housing (4); the brake disc (67) is connected to the output shaft I (21) of the drive motor or the output shaft II (61) of the drive motor via a spline shaft; The electromagnet (64) is embedded in the inner side of the brake housing (62), the armature (66) is arranged between the electromagnet (64) and the brake disc (67), and the armature (66) is connected to the brake housing (62) through an elastic guide component; when the electromagnet (64) is energized, the armature (66) and the electromagnet (64) are attracted; when the electromagnet (64) is de-energized, the elastic guide component pushes the armature (66) and the brake disc (67) to fit together, thereby achieving braking.

8. The redundant multi-power drive system based on differential speed coupling according to claim 7, characterized in that: The elastic guide assembly comprises a plurality of armature guide shafts (63) and a plurality of springs (65) which are circumferentially arranged on the inner side of the brake housing (62), wherein the plurality of armature guide shafts (63) are located on the inner side of the electromagnet (64), the armature (66) is slidably matched with the plurality of armature guide shafts (63), and the plurality of springs (65) are located on the outer side of the electromagnet (64) and abut against the armature (66).

9. The redundant multi-power drive system based on differential speed coupling according to claim 7, characterized in that: The brake disc (67) comprises a friction plate (671) and a brake disc body (672), wherein the brake disc body (672) is key-connected to the output shaft I (21) of the drive motor or the output shaft II (61) of the drive motor, and the brake disc body (672) is rotationally connected to the housing of the drive motor I (1) or the drive motor II (7) via a thrust ball bearing II (69), and the friction plate (671) is fixed to the front end surface of the brake disc body (672).

10. The redundant multi-power drive system based on differential speed coupling according to claim 7, characterized in that: An adjustment gasket (68) is provided between the brake housing (62) and the housing of the drive motor I (1) or the drive motor II (7).

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