Four-motor and WW gear train combined hub motor device

Abstract

A four-motor and WW gear train combined hub motor device comprises four motor devices, and each motor device comprises a motor driving device and a motor body device. A motor shaft of the motor body device is connected with the input end of the speed reduction system through an input gear, the output end of the speed reduction system is connected with the hub, and the hub is connected with the tire to achieve power output and transmission. The speed reduction system comprises an inner gear ring meshed with the input gear, the inner gear ring is connected with a duplex planet gear through a duplex planet gear shaft, one side of the duplex planet gear is meshed with a fixed end sun gear, and the fixed end sun gear is connected to a hub shaft. The other side of the duplex planet gear is meshed with an output end sun gear, the output end sun gear is connected to a hub, the output end sun gear is supported on a hub shaft through a bearing system, and power of the motor is transmitted to the hub; through the four motors and the WW gear train combined hub motor device, the advantages of multi-motor power division, safety, reliability, high energy utilization rate, convenience in heat dissipation, compact structure and the like are realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of wheel hub motors for new energy vehicles, and in particular relates to a wheel hub motor device combining four motors and a WW gear train. Background Art

[0002] In order to simplify control, traditional hub motor drive systems usually use a single motor drive, and then use a clutch and a complex transmission system to achieve different speed and torque requirements of electric vehicles. For example, a patent application named "An Automatic Speed ​​Shift Hub Motor" (publication number: CN 113715954A) discloses a single-motor driven double-stage planetary reduction hub system. Its structural principle is a main shaft, a hub, a power input member, a movement assembly arranged in the hub, and an automatic speed shift mechanism. The single-motor drive hub motor is mainly achieved through a clutch to meet the vehicle's output torque and speed requirements. However, the transmission system has a complex structure, low transmission efficiency, high cost, and a long development cycle.

[0003] At present, there are also multi-motor driven hub motors, the core of which is to achieve the speed and torque coupling between the dual motors through the transmission of multiple motors and reduction mechanisms. For example, a patent application named "A Hub Motor" (publication number: CN113824284A) discloses a dual-motor driven hub system, which forms a dual-motor coupled transmission system through the coupling of the rotor of the second motor after the transmission of the first motor. In this way, it is necessary to control the second motor when the second motor is not powered and the second rotor is already rotating, which makes the control difficult.

[0004] The reduction system of the hub motor widely adopts a planetary reduction device, so it is necessary to process the inner gear ring, which has a large radial size and is difficult to process. In addition, the reduction ratio of a single-stage planetary reducer is usually 3-5, so multiple stages of gear reduction are required to achieve the required torque. The motor is usually designed inside the reducer, which hinders the heat dissipation of the motor. For example, a patent application named "A Split-Axis Hub Motor" (publication number: CN 111327155 A) discloses a hub system driven by a single motor. Its structural principle is that the hub motor system is composed of a hub motor, a sun gear, a double-coupled planetary gear, an inner gear ring, etc. The double-coupled planetary gear drives the inner gear ring to rotate and finally drives the wheel forward. Its disadvantages are large radial size, small transmission ratio, low efficiency and unreliability of the hub motor.

[0005] In summary, the current wheel hub motor device for electric vehicles has the following shortcomings:

[0006] 1) The torque coupling of a single motor is achieved through a complex transmission system, and the structure is complex; 2) The single-motor drive method is widely used, which causes the motor to be unable to meet the optimal efficiency output under different working conditions of the whole vehicle, and the energy utilization rate is low. Failures caused by failures will directly paralyze the vehicle, with low fault tolerance and poor reliability; 3) The widely used reduction device outputs to the wheel hub through the inner ring gear, has a large radial size, and the transmission ratio is only 3-5, requiring a multi-stage reduction device with a large size; in addition, the motor is in the middle of the wheel hub, and the heat generated by the motor stator winding needs to be transmitted to the outside through the casing and the reduction device, requiring forced air cooling and water cooling, the system is complex, maintenance is difficult, and the motor cost is high. Summary of the invention

[0007] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide a four-motor and WW gear train combined wheel hub motor device, which combines four motors with the WW planetary gear train to form a wheel hub system structure in which the motor and the reducer are highly integrated; the four motors can be connected to the required motors according to the power demand of the whole vehicle to ensure that each motor operates in the optimal efficiency range; water cooling, oil cooling and forced air cooling are omitted, and the system is simple; the four identical motors have the advantages of modularization and low cost; the large ring gear of the planetary reducer is omitted, and the size is small.

[0008] In order to achieve the above object, the technical solution adopted by the present invention is:

[0009] A four-motor and WW gear train combined wheel hub motor device includes four identical first motor devices 35, second motor device 36, third motor device 37 and fourth motor device 39, each motor device includes a motor drive device and a motor body device; the motor shaft 24 of the motor body device is connected to the input end of the reduction system through the input gear 1, the output end of the reduction system is connected to the wheel hub 7, and the wheel hub 7 is connected to the tire 34 to realize the output and transmission of power.

[0010] The first motor drive device 17, the second motor drive device 18, the third motor drive device 19 and the fourth motor drive device 23 of the first motor device 35, the second motor device 36, the third motor device 37 and the fourth motor device 39 include a motor drive control circuit 21, and the motor drive control circuit 21 is fixed to the motor right frame 22 of the motor body device and the left frame 16 of the circuit board through pull rods 25 distributed along the circumferential direction, and the left frame 16 of the circuit board is connected to the right frame 22 of the motor.

[0011] The motor body device includes a motor right frame 22, which is connected to a motor left frame 29 via a motor frame pull rod 28. A motor stator 27 is provided inside the motor right frame 22 and the motor left frame 29. The motor stator 27 cooperates with a motor rotor 26 inside. The motor rotor 26 is connected to a motor shaft 24, and the motor shaft 24 is supported on the motor right frame 22 and the motor left frame 29 via a bearing system.

[0012] The reduction system includes an inner gear ring 2 meshing with the input gear 1, and the inner gear ring 2 is positioned on the hub shaft through a ball bearing system 12 and a bearing retaining ring; the inner gear ring 2 is connected to the planetary gear shaft 3, and a double planetary gear is supported on the planetary gear shaft 3 through a roller bearing system 5. The double planetary gear is positioned in the axial position of the double planetary gear through a hole elastic retaining ring 14 and a bearing system, and the bearing system is positioned with the planetary gear shaft 3 by an elastic retaining ring 15 on the shaft; the right planetary gear of the double planetary gear is meshed with the right fixed end sun gear 10, and the right fixed end sun gear 10 is connected to the hub shaft 20; the left planetary gear of the double planetary gear is meshed with the output end sun gear 9, and the output end sun gear 9 is connected to the hub 7, and the output end sun gear 9 is supported on the hub shaft 20 through a hub bearing 11; the left side of the planetary gear shaft 3 is connected to the planetary gear left pressure plate 6, and the planetary gear left pressure plate 6 is fixed to the inner gear ring 2 through the same axis as the planetary gear shaft 3.

[0013] There are three duplex planetary gears, which are distributed along the circumference of the right fixed end sun gear 10 and the output end sun gear 9, and are respectively the first duplex planetary gear 4, the second duplex planetary gear 30 and the third duplex planetary gear 31.

[0014] The outer side of the wheel hub is fixed by two locking nuts 32 .

[0015] The hub shaft 20 is connected to a steering system 38 .

[0016] The first motor device 35 , the second motor device 36 , the third motor device 37 , and the fourth motor device 39 are AC permanent magnet synchronous motors.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] (1) Since the present invention adopts a wheel hub motor combined with four motors and a WW wheel system, the four motors can be connected to one, two, three or three according to the power demand of the vehicle, which can make the wheel hub motor system have more flexible power distribution and realize torque coupling of multiple motors by switching between different modes.

[0019] (2) Since the multi-motor power splitting of the present invention allows the motors to work more in the optimal working range, the overall efficiency will be higher and the energy utilization rate can be improved. In addition, since the multiple motors are dispersed, the solution is safer, more reliable and has a higher fault tolerance rate than the traditional single-motor drive solution, which can prevent the loss of vehicle power due to motor failure.

[0020] (3) Since the present invention adopts the WW gear train, its double planetary gear avoids the traditional inner ring processing by fixing the sun gear, which reduces the cost and reduces the radial size of the reducer, making the overall structure more compact; in addition, since the four motor devices of the present invention are placed on the left side of the wheel hub and the stator is exposed, the ventilation and heat dissipation are excellent. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a front cross-sectional view of an embodiment of the present invention.

[0022] Figure 2 It is a left view of the combined wheel hub motor of four motors and WW gear train of the present invention.

[0023] Figure 3 It is a left view of the connection flange of the four motors and their drive system of the present invention.

[0024] Figure 4 It is a right side view of the combined wheel hub motor of four motors and WW gear train of the present invention. DETAILED DESCRIPTION

[0025] The present invention is described in detail below in conjunction with embodiments and drawings.

[0026] Reference Figure 1 , Figure 2 , Figure 3 and Figure 4 A four-motor and WW gear train combined wheel hub motor device includes four identical first motor devices 35, second motor devices 36, third motor devices 37 and fourth motor devices 39, each motor device includes a motor drive device and a motor body device; the motor shaft 24 of the motor body device is connected to the input gear 1 through a flat key or a spline, the input gear 1 is connected to the input end of the reduction system, and the power is transmitted from the input gear 1 to the reduction system; the output end of the reduction system is connected to the wheel hub 7, and the wheel hub 7 is connected to the tire 34 to realize the output and transmission of power.

[0027] Reference Figure 1 , Figure 3The first motor device 35, the second motor device 36, the third motor device 37 and the fourth motor device 39 include the first motor drive device 17, the second motor drive device 18, the third motor drive device 19 and the fourth motor drive device 23 of the motor drive control circuit 21. The motor drive control circuit 21 is fixed to the motor right frame 22 of the motor body device and the left frame 16 of the circuit board through 6 pull rods 25 distributed along the circumferential direction. The left frame 16 of the circuit board is connected to the right frame 22 of the motor through the circuit board fixing bolts 33.

[0028] Reference Figure 1 The motor body device includes a right motor frame 22, which is connected to a left motor frame 29 through a motor frame pull rod 28, and the motor frame pull rod 28 is fixed by nuts on both sides. A motor stator 27 is provided inside the right motor frame 22 and the left motor frame 29, and the motor stator 27 cooperates with a motor rotor 26 inside. The motor rotor 26 is connected to the motor shaft 24 through a flat key or a spline, and the motor shaft 24 is supported on the right motor frame 22 and the left motor frame 29 through a bearing system. The motor rotor 26 is positioned by sleeves on both sides and the right motor frame 22 and the left motor frame 29.

[0029] Reference Figure 1 , Figure 2 The reduction system includes an inner gear ring 2 meshing with the input gear 1, and the inner gear ring 2 is positioned on the hub shaft through a ball bearing system 12 and an elastic retaining ring; the inner gear ring 2 and the planetary gear shaft 3 are positioned by the shaft shoulder and the elastic retaining ring 8 at the end of the planetary gear shaft 3, and the inner gear ring 2 is connected to the planetary gear shaft 3 through a flat key or a spline, and the planetary gear shaft 3 supports a double planetary gear through a roller bearing system 5, and the double planetary gear is positioned in the axial position of the double planetary gear through a hole elastic retaining ring 14 and a bearing system, and the bearing system is positioned with the planetary gear shaft 3 by a shaft elastic retaining ring 15; the right side of the double planetary gear The planetary gear is meshed with the right fixed end sun gear 10, and the right fixed end sun gear 10 is connected to the hub shaft 20 through a flat key or a spline; the left planetary gear of the double planetary gear is meshed with the output end sun gear 9, and the output end sun gear 9 is connected to the hub 7 through the hub bolt 13, and the output end sun gear 9 is supported on the hub shaft 20 through the hub bearing 11; the left side of the planetary gear shaft 3 is connected to the planetary gear left pressure plate 6, and the outer side of the planetary gear left pressure plate 6 is fixed by an elastic retaining ring 8; the planetary gear left pressure plate 6 is fixed to the inner gear ring 2 through the same axis as the planetary gear shaft 3, and the two sides of the axis are positioned by elastic retaining rings.

[0030] like Figure 2As shown, there are three double-coupled planetary gears, which are distributed circumferentially along the right fixed end sun gear 10 and the output end sun gear 9, namely the first double-coupled planetary gear 4, the second double-coupled planetary gear 30 and the third double-coupled planetary gear 31; the outer side of the hub is fixed by two locking nuts 32.

[0031] like Figure 4 As shown, the output ends of the first motor device 35 , the second motor device 36 , the third motor device 37 , and the fourth motor device 39 drive the inner gear ring 2 through four input gears 1 ; the hub shaft 20 is connected to a steering system 38 .

[0032] The first motor device 35 , the second motor device 36 , the third motor device 37 , and the fourth motor device 39 are AC permanent magnet synchronous motors.

[0033] The working principle of the present invention is:

[0034] Four independent first motor devices 35, second motor devices 36, third motor devices 37, and fourth motor devices 39 respectively rely on four independent first motor drive devices 17, second motor drive devices 18, third motor drive devices 19, and fourth motor drive devices 23 to control the operation of the motors. The output shafts of the motors transmit power to the corresponding input gears 1, and the four input gears 1 jointly drive the inner ring 2, which is supported on the hub shaft 20, and the inner ring 2 supports a double-coupled planetary gear through the planetary gear shaft 3. The left planetary gear of the double-coupled planetary gear is meshed with the output end sun gear 9, so the power is transmitted to the output end sun gear 9 through the inner ring 2, and the power is finally transmitted to the wheel hub 7 and the tire 34; the right planetary gear of the double-coupled planetary gear is meshed with the fixed end sun gear 10, and the fixed end sun gear 10 is connected to the hub shaft 20, and the hub shaft 20 is connected to the reversing system 38 to realize the control of vehicle steering.

[0035] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the protection scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that modifications or equivalent replacements of the technical solutions of the present invention are all within the protection scope of the present invention.

Claims

1. A four-motor and WW gear train combined wheel hub motor device, comprising four identical first motor devices (35), second motor devices (36), third motor devices (37) and fourth motor devices (39), characterized in that: Each motor device comprises a motor drive device and a motor body device; the motor shaft (24) of the motor body device is connected to the input end of the reduction system via an input gear (1), the output end of the reduction system is connected to the wheel hub (7), and the wheel hub (7) is connected to the tire (34) to achieve power output and transmission.

2. The four-motor and WW gear train combined wheel hub motor device according to claim 1, characterized in that: The first motor drive device (17), the second motor drive device (18), the third motor drive device (19) and the fourth motor drive device (23) of the first motor device (35), the second motor device (36), the third motor device (37) and the fourth motor device (39) include a motor drive control circuit (21); the motor drive control circuit (21) is fixed to the motor right frame (22) and the circuit board left frame (16) of the motor body device via a pull rod (25) distributed along the circumferential direction; the circuit board left frame (16) is connected to the motor right frame (22).

3. The four-motor and WW gear train combined wheel hub motor device according to claim 1, characterized in that: The motor body device comprises a right motor frame (22), the right motor frame (22) is connected to a left motor frame (29) through a motor frame pull rod (28), a motor stator (27) is provided inside the right motor frame (22) and the left motor frame (29), the motor stator (27) cooperates with a motor rotor (26), the motor rotor (26) is connected to a motor shaft (24), and the motor shaft (24) is supported on the right motor frame (22) and the left motor frame (29) through a bearing system.

4. The four-motor and WW gear train combined wheel hub motor device according to claim 1, characterized in that: The reduction system comprises an inner gear ring (2) meshing with an input gear (1), the inner gear ring (2) being positioned on a hub shaft (20) via a ball bearing system (12) and a bearing retaining ring; the inner gear ring (2) being connected to a planetary gear shaft (3), a double planetary gear being supported on the planetary gear shaft (3) via a roller bearing system (5), the double planetary gear being positioned axially by an elastic retaining ring (14) and a bearing system through a hole, the bearing system being positioned with the planetary gear shaft (3) by an elastic retaining ring (15) by a shaft; the double planetary gear The right planetary gear meshes with the right fixed end sun gear (10), and the right fixed end sun gear (10) is connected to the wheel hub shaft (20); the left planetary gear of the double planetary gear meshes with the output end sun gear (9), and the output end sun gear (9) is connected to the wheel hub (7), and the output end sun gear (9) is supported on the wheel hub shaft (20) through the wheel hub bearing (11); the left side of the planetary gear shaft (3) is connected to the left pressure plate (6) of the planetary gear, and the left pressure plate (6) of the planetary gear is fixed to the inner gear ring (2) through the same axis as the planetary gear shaft (3).

5. The four-motor and WW gear train combined wheel hub motor device according to claim 4, characterized in that: There are three double-linked planetary gears, which are distributed along the circumference of the right fixed end sun gear (10) and the output end sun gear (9), and are respectively a first double-linked planetary gear (4), a second double-linked planetary gear (30) and a third double-linked planetary gear (31).

6. The four-motor and WW gear train combined wheel hub motor device according to claim 1, characterized in that: The outer side of the wheel hub is fixed by two locking nuts (32).

7. The four-motor and WW gear train combined wheel hub motor device according to claim 1, characterized in that: The hub shaft (20) is connected to a steering system (38).

8. The four-motor and WW gear train combined wheel hub motor device according to claim 1, characterized in that: The first motor device (35), the second motor device (36), the third motor device (37) and the fourth motor device (39) are AC permanent magnet synchronous motors.

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