CN116279770B - Wheel independent steering structure based on hub motor - Google Patents

Abstract

The present invention discloses a wheel independent steering structure based on a hub motor, which is mainly composed of three parts: a drive motor, a suspension, and a steering. The main components include a hub motor, a suspension claw plate, a lower cantilever, an upper cantilever, a main shock absorber, an auxiliary shock absorber, a large bevel gear, a small bevel gear, and a steering motor. The drive motor and the suspension are threadedly connected with a claw plate nut, and the various parts of the suspension are connected with a pin shaft. The steering motor and the small bevel gear are connected with a coupling. The present invention designs a set of independent steering devices based on the hub motor drive mode, which is suitable for the field of electric vehicles, can enable the wheel to complete large-angle steering, and realize the lateral driving or in-situ steering of the vehicle. In view of the single status of the existing independent steering wheel suspension design, a new structural design is proposed to improve the driving comfort of the vehicle. The design is simple in structure and easy to process, which can provide a useful reference for the design of independent wheel steering.

Description

A wheel independent steering structure based on wheel hub motor

Technical Field

The invention belongs to the field of electric vehicles, and in particular relates to a wheel independent steering and suspension structure driven by a hub motor.

technical background

Nowadays, new energy electric vehicles are vigorously promoted, wheel hub motor technology is further studied, and wheel independent steering technology has gradually attracted the attention of researchers due to its unique advantages. Combining wheel hub motor with wheel independent steering technology can enable each wheel of the vehicle to independently realize driving, steering and braking functions, maximizing the function of the wheel. However, the existing wheel hub motor has a large unsprung mass and a large moment of inertia, and the traditional suspension structure is difficult to meet the shock absorption requirements.

Patent CN202111060420.5 discloses an independently steered and independently driven wheel-side motor structure, which features include a rim, a bracket connected to the side of the rim, and a steering assembly and a drive assembly respectively arranged on the bracket. A disc is provided on the inner side of the rim, and the bracket and the drive assembly are respectively connected to the disc. The steering mechanism adopts a worm gear reduction motor, and the wheel is driven by the wheel-side motor. This structure can realize independent steering of a single wheel, and the worm gear has a self-locking function. The structure is simple and easy to implement, but placing the drive motor in the suspension is not conducive to power transmission, the steering mechanism has a large load, and the worm gear reduction mechanism has difficulty in heat dissipation.

Patent CN202121470816.2 discloses an independent steering mechanism, which includes a traveling wheel with a hub motor assembly, a suspension assembly connected between the traveling wheel and the vehicle body, and a steering drive assembly arranged on the vehicle body and transmission-connected to the suspension assembly. The suspension assembly is arranged to be tilted backward relative to the forward direction of the vehicle, and can generate a restoring torque during driving. However, the suspension part of the mechanism is only equipped with a damper, and the shock absorption effect is poor, and the comfort needs to be improved. The supporting wheel component is in the shape of a fork arm, which is difficult to apply to vehicles with large loads.

Patent CN201610020862.X discloses a suspension and steering system for a distributed drive independent steering electric vehicle, including wheels, hub motors, wheel brackets, brakes, a steering system and a double wishbone suspension system. The steering system is mounted on a mounting bracket of the vehicle body, the wheel bracket is connected to the output end of the steering system, and the double wishbone suspension system is mounted on the wheel bracket. The mechanism integrates a double wishbone suspension system with a lateral stabilizer, which improves the vehicle's operational stability. However, the wheel bracket is too large, occupying a large amount of steering space, and also increasing the load on the steering motor, which is not conducive to lightweight design.

Considering that the wheel hub motor drive combined with independent steering can save a lot of transmission components, has high energy utilization efficiency, and can realize multiple driving modes, but there are very few such design schemes in the electric vehicle market today. It is necessary to propose a wheel independent steering structure based on the wheel hub motor, which fully considers the large mass of the wheel hub motor, requires good shock absorption effect, and the steering mechanism has sufficient output torque, which is conducive to heat dissipation and will not self-lock so as to feedback road feel. At the same time, it takes into account many advantages such as simple manufacturing principle and good economic benefits.

Summary of the invention

Aiming at the current lack of independent steering design for the hub motor wheels of electric vehicles, a wheel device integrating driving, shock absorption and steering is proposed, which can save a lot of transmission parts of traditional cars and has good suspension shock absorption effect. Each wheel has independent steering function. The design is simple and clear, easy to process, and has good social and economic value and research prospects.

The present invention adopts the following technical scheme to achieve the above object:

A wheel independent steering structure based on a hub motor comprises a steering motor, a coupling, a small bevel gear, a large bevel gear, a steering shaft, a tire, a wheel rim, a hub motor, a brake disc, a claw plate pin shaft, a claw plate nut, a fixed shaft, a suspension claw plate, a second lower cantilever pin shaft, a lower cantilever, a first lower cantilever pin shaft, an auxiliary shock absorber, a main shock absorber, an upper cantilever pin shaft, an upper cantilever, a steering bracket, a tapered roller bearing, spline teeth, a clamping block, a supporting roller, a motor dust cover, a motor housing, a hub motor bearing, a hub center disc, a motor fixed winding and a motor permanent magnet.

The device consists of three modules: a drive motor, a suspension and a steering. The suspension part consists of the claw plate pin shaft, the claw plate nut, the fixed shaft, the suspension claw plate, the second lower cantilever pin shaft, the lower cantilever, the first lower cantilever pin shaft, the auxiliary shock absorber, the main shock absorber, the upper cantilever pin shaft, and the upper cantilever. The suspension claw plate and the fixed shaft are screwed and fixed by the claw plate nut and kept relatively still. The lower fork arm of the suspension claw plate is connected to the lower cantilever by the second lower cantilever pin shaft, the lower cantilever is connected to the upper cantilever by the first lower cantilever pin shaft, the upper fork arm of the suspension claw plate is connected to the main shock absorber and the auxiliary shock absorber by the claw plate pin shaft, the main shock absorber is connected to the upper cantilever by the upper cantilever pin shaft, and the auxiliary shock absorber is connected to the lower cantilever by the first lower cantilever pin shaft.

The transformation motor is connected to the small bevel gear shaft through the coupling, the small bevel gear and the large bevel gear are gear-engaged, the large bevel gear and the steering shaft are keyed, the steering shaft and the steering bracket are supported by the tapered roller bearing and can rotate around their own center axis, the steering shaft and the spline teeth are keyed, the spline teeth and the upper cantilever are interference fit, the steering shaft and the clamping block are threadedly connected, the steering bracket and the upper cantilever include the supporting roller, and the two can rotate relative to each other around the center line of the steering shaft.

The suspension shock absorber part consists of two main shock absorbers and auxiliary shock absorbers with different spring damping coefficients. In order to limit the maximum travel range of the auxiliary shock absorber, the center point of the claw plate pin shaft shall not cross the line connecting the center of the upper cantilever pin shaft and the center of the second lower cantilever pin shaft during the suspension movement. Considering that the large bevel gear and the small bevel gear of the steering part rotate relatively slowly, oil lubrication is difficult, so grease lubrication is adopted.

Compared with the prior art, the beneficial effects of the present invention are as follows:

1. The independent steering wheel suspension has good comfort and safety. The suspension design uses main and auxiliary shock absorbers. The main shock absorber is mainly used to absorb the vertical impact from the ground, and the auxiliary shock absorber is used to absorb the impact from a certain side of the wheel, which greatly improves the driving comfort of the vehicle. As the body load increases, the wheelbase will increase accordingly, improving the driving safety of the vehicle. The overall movement stroke of the suspension is large, the manufacturing cost is low, and it can meet the load requirements under various working conditions and can be widely promoted.

2. The steering system has fast response and good maneuverability. The steering part is composed of a steering motor and a bevel gear reduction structure. It has smooth transmission, reliable and stable operation, and is combined with a wheel hub motor to directly drive the wheels to rotate. The entire steering mechanism can make the wheels turn independently around the steering axis. With the steering solution, the wheels can move horizontally, diagonally, and turn on the spot, greatly expanding the driving mode of the car.

3. The steering unit is highly integrated. This design integrates the wheel steering system, suspension assembly, wheel hub motor and brake. A single wheel has driving, steering and braking functions. Compared with traditional cars, it omits a large number of transmission parts such as clutch and gearbox. It occupies a small space, has a compact structure, high flexibility, and has broad application value.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a schematic diagram of the independent steering wheel and suspension structure;

Fig. 2 is a cross-sectional view of the steering system;

FIG3 is a top view of the steering system;

FIG4 is a cross-sectional view of an outer rotor hub motor;

FIG5 is a front view of the independent steering wheel and suspension structure;

Among them: 1 steering motor; 2 coupling; 3 small bevel gear; 4 large bevel gear; 5 steering shaft; 6 tire; 7 rim; 8 hub motor; 9 brake disc; 10 claw plate pin; 11 claw plate nut; 12 fixed shaft; 13 suspension claw plate; 14 second lower cantilever pin; 15 lower cantilever; 16 first lower cantilever pin; 17 auxiliary shock absorber; 18 main shock absorber; 19 upper cantilever pin; 20 upper cantilever; 21 steering bracket; 501 tapered roller bearing; 502 spline teeth; 503 clamping block; 504 supporting roller; 801 motor dust cover; 802 motor housing; 803 hub motor bearing; 804 hub center disc; 805 motor fixed winding; 806 motor permanent magnet.

Detailed ways

The present invention relates to a wheel independent steering structure based on a wheel hub motor, which is mainly composed of a steering deceleration module, a wheel suspension module and a wheel hub motor drive module. The present invention is further described below in conjunction with the accompanying drawings.

As shown in Figures 1, 2 and 3, the steering deceleration part is composed of a steering motor 1, a coupling 2, a small bevel gear 3, a large bevel gear 4 and a steering shaft 5. When the driver turns the steering wheel, the steering motor 1 receives a steering instruction, and the vehicle steering control unit calculates and outputs the corresponding angle. The output shaft of the steering motor 1 is connected to the small bevel gear 3 through the coupling 2, the small bevel gear 3 is externally meshed with the large bevel gear 4, the large bevel gear 4 is connected to the steering shaft 5 through a key, and the steering shaft 5 is connected to the spline teeth 502 with a key, and the spline hole on the upper cantilever 20 is interference fit with the spline teeth 502, and finally the output torque of the steering motor 1 is transmitted to the upper cantilever 20 through the bevel gear deceleration, pushing the upper cantilever 20 to rotate, driving the wheel to steer. As shown in Figures 2 and 3, the stepped shaft on the steering shaft 5 abuts against the upper surface of the inner ring of the tapered roller bearing 501, the outer ring of the tapered roller bearing 501 is interference fit with the steering bracket 21, and the lower surface of the outer ring of the tapered roller bearing 501 abuts against the stepped hole on the steering bracket 21, thereby ensuring the axial positioning of the tapered roller bearing 501. The steering bracket 21 is fixedly connected to the vehicle body frame and remains relatively stationary with the vehicle body. When the upper cantilever 20 rotates around the center line of the steering shaft 5, the vertical force from the ground is transmitted to the upper cantilever 20, causing the upper cantilever 20 and the steering shaft 5 to bear a large bending moment. A supporting roller 504 is provided between the steering bracket 21 and the upper cantilever 20. The supporting roller 504 can rotate around the center axis of the steering shaft 5 in the groove, and can also transmit the force on the upper cantilever 20 to the steering bracket 21, thereby dispersing the force points of the upper cantilever 20 and providing a guarantee for the stable rotation of the steering mechanism. The steering shaft 5 is connected to the pressing block 503 by threads, which provides a pre-tightening force between the steering bracket 21 and the upper cantilever 20, and also ensures that the wheel will not fall when suspended in the air.

As shown in Fig. 1 and Fig. 4, the suspension part is composed of an upper cantilever 20, a main shock absorber 18, an auxiliary shock absorber 17, a lower cantilever 15, and a suspension claw plate 13. The steering shaft 5 drives the upper cantilever 20 to rotate, and the upper cantilever 20 and the main shock absorber 18 are connected by an upper cantilever pin 19. The main shock absorber 18 and the upper cantilever pin 19 are clearance-matched to ensure that the two can rotate relative to each other. The upper cantilever 20, the auxiliary shock absorber 17 and the lower cantilever 15 are clearance-matched and connected with the first lower cantilever pin 16. The lower cantilever 15 and the suspension claw plate 13 are clearance-matched and connected with the second lower cantilever pin 14. The suspension claw plate 13 is passed through the center hole on the fixed shaft 12, and is threadedly connected by the claw plate nut 11 to press the suspension claw plate 13 on the shoulder of the fixed shaft 12. The main shock absorber 18, the auxiliary shock absorber 17, and the upper fork arm of the suspension claw plate 13 are clearance-matched and connected with the claw plate pin 10. When the wheel When there is a sudden vertical impact on the inside or outside, the wheel rotates around the center of the second lower cantilever pin 14, and the auxiliary shock absorber 17 quickly absorbs the lateral impact of the wheel. When the body load is large or the vertical load at the center of the wheel increases, the wheel mainly rotates around the first lower cantilever pin 16, and the main shock absorber 18 absorbs the vertical impact at the center of the wheel. It should be pointed out that when the wheel rotates around the second lower cantilever pin 14, the center of the claw plate pin 10 cannot exceed the line connecting the upper cantilever pin 19 and the second lower cantilever pin 14, that is, when the suspension moves to the point where the three points of the upper suspension pin 19, the claw plate pin 10, and the second lower cantilever pin 14 are in the same line, the first lower cantilever pin 16 reaches the maximum compression position, limiting the working range of the suspension.

As shown in Figures 1 and 5, the hub motor 8 is an outer rotor hub motor drive part composed of a dust cover 801, a motor housing 802, a hub motor bearing 803, a hub center disk 804, a motor fixed winding 805 and a motor permanent magnet 806. The tire 6 is embedded in the rim 7, the hub center disk 804 on the rim 7 is bolted to the motor housing 802, the motor housing 802 is bolted to the motor dust cover 801, the brake disc 9 is bolted to the motor dust cover 801, and the motor cable enters the center hole of the fixed shaft 12 and is connected to the motor fixed winding 805. When the motor is working, the motor permanent magnet 806 is rotated by the magnetic field force, driving the motor housing 802 and the motor dust cover 801 to rotate around the fixed shaft 12 through the hub motor bearing 803, and further driving the rim 7, the tire 6 and the brake disc 9 to rotate, thereby realizing the wheel driving function.

The structural features of the present invention are described in detail above based on the illustrations. The present invention does not limit the scope of implementation as shown in the illustrations. Any changes made in accordance with the concept of the present invention, or modifications to equivalent embodiments with equivalent changes, which still do not exceed the spirit covered by the description and illustrations, should be within the protection scope of the present invention.

Claims (4)

1. A wheel independent steering structure based on a wheel hub motor, comprising a steering motor (1), a coupling (2), a small bevel gear (3), a large bevel gear (4), a steering shaft (5), a tire (6), a wheel rim (7), a wheel hub motor (8), a brake disc (9), a claw disc pin shaft (10), a claw disc nut (11), a fixed shaft (12), a suspension claw disc (13), a second lower cantilever pin shaft (14), a lower cantilever (15), a first lower cantilever pin shaft (16), an auxiliary shock absorber (17), and a main shock absorber (18 ), upper cantilever pin (19), upper cantilever (20), steering bracket (21), tapered roller bearing (501), spline teeth (502), pressing block (503), supporting roller (504), motor dust cover (801), motor housing (802), hub motor bearing (803), hub center disk (804), motor fixed winding (805), motor permanent magnet (806); the suspension part is composed of the claw plate pin (10), the claw plate nut (11), the fixed shaft (12 ), the suspension claw plate (13), the second lower cantilever pin shaft (14), the lower cantilever (15), the first lower cantilever pin shaft (16), the auxiliary shock absorber (17), the main shock absorber (18), the upper cantilever pin shaft (19), and the upper cantilever (20), wherein the suspension claw plate (13) and the fixed shaft (12) are screwed and fixed by the claw plate nut (11) and kept relatively still, and the lower fork arm of the suspension claw plate (13) and the lower cantilever (15) are screwed and fixed by the claw plate nut (11). The lower cantilever (15) and the upper cantilever (20) are connected by a second lower cantilever pin shaft (14); the lower cantilever (15) and the upper cantilever (20) are connected by a first lower cantilever pin shaft (16); the upper fork arm of the suspension claw plate (13) and the main shock absorber (18) and the auxiliary shock absorber (17) are connected by the claw plate pin shaft (10); the main shock absorber (18) and the upper cantilever (20) are connected by the upper cantilever pin shaft (19); and the auxiliary shock absorber (17) and the lower cantilever (15) are connected by the first lower cantilever pin shaft (16). 2. A wheel independent steering structure based on a hub motor according to claim 1, characterized in that the steering motor (1) is connected to the small bevel gear (3) shaft through the coupling (2), the small bevel gear (3) and the large bevel gear (4) are gear meshing transmission, the large bevel gear (4) and the steering shaft (5) are keyed, the steering shaft (5) and the steering bracket (21) are supported by the tapered roller bearing (501) and can rotate around its own central axis, the steering shaft (5) and the spline teeth (502) are keyed, the spline teeth (502) and the upper cantilever (20) are interference fit, the steering shaft (5) and the pressing block (503) are threadedly connected, the steering bracket (21) and the upper cantilever (20) include the supporting roller (504), and the steering bracket (21) and the upper cantilever (20) can rotate relative to each other around the center line of the steering shaft (5). 3. According to claim 1, a wheel independent steering structure based on a hub motor is characterized in that the suspension shock absorbing part is composed of two main shock absorbers (18) and auxiliary shock absorbers (17) with different spring damping coefficients. In order to limit the maximum travel range of the maximum auxiliary shock absorber (17), during the suspension movement, the center point of the claw plate pin shaft (10) shall not cross the line connecting the center of the upper cantilever pin shaft (19) and the center of the second lower cantilever pin shaft (14). 4. According to claim 1, a wheel independent steering structure based on a hub motor is characterized in that the large bevel gear (4) and the small bevel gear (3) of the steering part rotate relatively slowly, and oil lubrication is difficult, so grease lubrication is adopted.