CN212500640U - Electric power-assisted steering system for unmanned single-wheel steering vehicle - Google Patents

Abstract

The utility model discloses an unmanned single wheel turns to electric power assisted steering system for vehicle, including helping hand motor, reduction gears and output shaft, reduction gears include with first worm, the second worm that helping hand motor connects, set up on the second worm and with first worm engaged with first worm wheel and set up in on the output shaft and with second worm engaged with second worm wheel. The utility model discloses an unmanned driving single wheel turns to electric power assisted steering system for vehicle adopts second grade worm gear reduction gears, and the structure is more simplified, and the volume is littleer, and the cost is lower, adopts angle closed-loop control, eliminates the angle distortion risk.

Description

Electric power-assisted steering system for unmanned single-wheel steering vehicle

Technical Field

The utility model belongs to the technical field of vehicle steering system, specifically speaking, the utility model relates to an unmanned driving single wheel turns to electric power assisted steering system for vehicle.

Background

The existing electric power-assisted steering system for the unmanned single-wheel steering vehicle adopts a planetary gear speed reducing mechanism for secondary speed reduction, and has the defects of complex structure, large integral volume and high cost; and the control mode of the steering system is angle open loop control, so that the risk of angle distortion exists.

SUMMERY OF THE UTILITY MODEL

The utility model discloses aim at solving one of the technical problem that exists among the prior art at least. Therefore, the utility model provides an unmanned single wheel turns to electric power assisted steering system for vehicle, the purpose is the simplified structure.

In order to realize the purpose, the utility model discloses the technical scheme who takes does: unmanned single wheel steering vehicle uses electric power assisted steering system, including helping hand motor, reduction gears and output shaft, reduction gears include with first worm, the second worm that helping hand motor is connected, set up on the second worm and with first worm engaged with first worm wheel and set up in on the output shaft and with second worm engaged with second worm wheel.

The speed reducing mechanism comprises a steering engine shell, the first worm is installed in the steering engine shell through a first bearing and a first shaft sleeve, a bearing pressing plate used for axially limiting the first bearing is arranged in the steering engine shell, and an inner ring of the first bearing is in interference fit with the first worm.

The second worm is installed on the steering gear shell through a second bearing, the inner ring of the second bearing is in interference fit with the second worm, and the end face of the first worm wheel is attached to the inner ring of the second bearing.

The reduction gears still include with gear box casing and the worm wheel upper cover that the steering gear casing is connected, the steering gear casing is located between gear box casing and the worm wheel upper cover, the one end of second worm is passed through the third bearing and is installed on the worm wheel upper cover, and the other end of second worm passes through the second bushing and installs on the gear box casing, first worm wheel is located between second bearing and the third bearing.

The inner ring of the third bearing is in interference fit with the second worm, and the outer ring of the third bearing is in clearance fit with the upper cover of the worm wheel.

The steering gear box is characterized in that a first sealing ring is arranged between the steering gear box shell and the power-assisted motor, a second sealing ring is arranged between the reduction gear box shell and the steering gear box shell, a third sealing ring is arranged between the worm gear upper cover and the steering gear box shell, and the first sealing ring, the second sealing ring and the third sealing ring are all O-shaped rings.

The output shaft is installed on the speed reduction box shell through a fourth bearing, the output shaft is installed on the installation base through a fifth bearing, the installation base is connected with the speed reduction box shell, the inner ring of the fourth bearing is in interference fit with the output shaft, and the outer ring of the fifth bearing is in interference fit with the installation base.

And a wave-shaped elastic gasket is arranged between the fourth bearing and the shell of the reduction gearbox and is clamped between the mounting surface in the shell of the reduction gearbox and the outer ring of the fourth bearing.

The gearbox shell with set up the fifth sealing washer between the installation base, the fifth sealing washer is O type circle, set up the skeleton oil blanket between output shaft and the installation base.

Unmanned single wheel turns to vehicle with electric power assisted steering system still including set up in the epaxial torque angle sensor of output, torque angle sensor is located the inside of reducing gear box casing, torque angle sensor is connected with the sensor pencil, is provided with waterproof sealing device on the reducing gear box casing, waterproof sealing device includes the sealing plug that contacts with the outer wall of reducing gear box casing and sticiss the sealing plug at the pencil clamp plate on the reducing gear box casing, the sealing plug has the hole of dodging that lets the sensor pencil pass.

The utility model discloses an unmanned driving single wheel turns to electric power assisted steering system for vehicle adopts second grade worm gear reduction gears, and the structure is more simplified, and the volume is littleer, and the cost is lower, adopts angle closed-loop control, eliminates the angle distortion risk.

Drawings

The description includes the following figures, the contents shown are respectively:

FIG. 1 is a partial cross-sectional view of an electric power steering system for an unmanned single-wheel steerable vehicle according to the present invention;

FIG. 2 is another partial cross-sectional view of the electric power steering system for an unmanned single-wheel-steered vehicle of the present invention;

FIG. 3 is another partial cross-sectional view of the electric power steering system for an unmanned single-wheel-steered vehicle of the present invention;

FIG. 4 is a schematic view of a steering controller

FIG. 5 is a schematic structural view of an electric power steering system for an unmanned single-wheel steerable vehicle according to the present invention;

FIG. 6 is another schematic structural view of the electric power steering system for an unmanned single-wheel-steered vehicle according to the present invention;

FIG. 7 is a cross-sectional view of the sealing plug;

fig. 8 is a sectional view of a sealing structure at a wire harness passage hole;

FIG. 9 is a schematic structural view of a wire harness platen;

FIG. 10 is a schematic view of the present invention showing the operation state of the electric power steering system for the unmanned single-wheel-steered vehicle;

labeled as: 1. a booster motor; 2. a coupling assembly; 3. a first bearing; 4. a worm gear upper cover; 5. an upper cover plug; 6. a first worm gear; 7. a first bushing; 8. a parallel bond; 9. installing a base; 10. a first worm; 11. a steering housing; 12. a bearing pressure plate; 13. a first seal ring; 14. a wire harness pressing plate; 1401. a pressing part; 1402. an installation part; 15. a gearbox housing; 16. a second shaft sleeve; 17. a sensor harness; 18. mounting a bracket; 19. a steering controller; 1901. a steering controller signal input; 1902. a signal detection end of the steering controller; 1903. a power supply output end of the steering controller; 1904. a power supply input end of the steering controller; 20. a second seal ring; 21. a second bearing; 22. a third seal ring; 23. a second worm; 24. a third bearing; 25. a fourth seal ring; 26. an elastic wave washer; 27. a fourth bearing; 28. a second worm gear; 29. a fifth seal ring; 30. a fifth bearing; 31. an output shaft; 32. framework oil seal; 33. a torque angle sensor; 34. a sealing plug; 3401. a seal cartridge body; 3402. a flange; 3403. an axial seal ring; 3404. a radial seal ring; 3405. avoiding holes; 35. a bolt; 36. a steering bracket; 37. and a steering wheel.

Detailed Description

The following detailed description of the embodiments of the present invention will be given with reference to the accompanying drawings, for the purpose of helping those skilled in the art to understand more completely, accurately and deeply the conception and technical solution of the present invention, and to facilitate its implementation.

It should be noted that, in the following embodiments, the terms "first", "second", "third", "fourth" and "fifth" do not represent absolute differences in structure and/or function, nor represent a sequential order of execution, but merely for convenience of description.

As shown in fig. 1 to 10, the utility model provides an unmanned single wheel turns to electric power assisted steering system for vehicle, including moment of torsion angle sensor 33, steering controller, helping hand motor 1, reduction gears and output shaft 31, helping hand motor 1 passes through reduction gears and is connected with output shaft 31, and the revolving force that helping hand motor 1 produced passes through reduction gears and transmits to output shaft 31, drives output shaft 31 and rotates. The speed reducing mechanism comprises a first worm 10 connected with the booster motor 1, a second worm 23, a first worm wheel 6 arranged on the second worm 23 and meshed with the first worm 10, and a second worm wheel 28 arranged on the output shaft 31 and meshed with the second worm 23.

Specifically, as shown in fig. 1 to 3, the speed reducing mechanism further includes a steering gear housing 11, a reduction gear housing 15 and a worm wheel upper cover 4, the steering gear housing 11 is fixedly connected to the power-assisted motor 1, the reduction gear housing 15 and the worm wheel upper cover 4 are connected to the steering gear housing 11, the steering gear housing 11 is located between the reduction gear housing 15 and the worm wheel upper cover 4, an inner cavity of the steering gear housing 11 is communicated with an inner cavity of the reduction gear housing 15 and an inner cavity of the worm wheel upper cover 4, and the inner cavity of the steering gear housing 11, the inner cavity of the reduction gear housing 15 and the inner cavity of the worm wheel upper cover 4 form a space for accommodating the first worm 10, the second worm 23, the first worm wheel 6 and the second worm wheel 28. The axial line of the first worm 10 is spatially vertical to the axial line of the second worm 23, the axial line of the output shaft 31 is parallel to the axial line of the first worm 10, the end part of the first worm 10 is connected with a motor shaft of the power-assisted motor 1 through the coupling component 2, and after the power-assisted motor 1 runs, the first worm 10 is driven to rotate through the coupling component 2.

As shown in fig. 1 and 2, the first worm 10 is mounted inside a steering gear housing 11 through the first bearing 3 and the first bushing 7, a bearing pressure plate 12 for axially limiting the first bearing 3 is disposed in the steering gear housing 11, an inner ring of the first bearing 3 is in interference fit with the first worm 10, and an outer ring of the first bearing 3 is mounted in the steering gear housing 11. The bearing pressure plate 12 limits the axial movement of the first bearing 3, the power-assisted motor 1 is connected with one end of a first worm 10 through the coupling component 2, the other end of the first worm 10 is arranged in an inner cavity of the steering gear shell 11 through a first shaft sleeve 7, and the first shaft sleeve 7 supports the first worm 10. The first shaft sleeve 7 is a cylinder with two open ends and a hollow interior, and the first shaft sleeve 7 is sleeved on the first worm 10 and is coaxial with the first worm.

The steering gear housing 11 is connected with the power-assisted motor 1 through a bolt, and correspondingly, a threaded hole for inserting the bolt is formed in the steering gear housing 11. As shown in fig. 1, a first sealing ring is arranged between the steering gear housing 11 and the power-assisted motor 1, the first sealing ring is used for sealing between the power-assisted motor 1 and the steering gear housing 11, and the first sealing ring is an O-ring.

As shown in fig. 1 and 2, the second worm 23 is mounted on the steering gear housing 11 through the second bearing 21, an inner ring of the second bearing 21 is in interference fit with the second worm 23, an end surface of the first worm wheel 6 is attached to the inner ring of the second bearing 21, and the first worm wheel 6 is coaxially and fixedly connected with the second worm 23. And spin riveting for axially limiting the second bearing 21 is arranged in the inner cavity of the steering gear shell 11, the spin riveting is fixedly connected with the steering gear shell 11, and the spin riveting limits the axial movement of the second bearing 21. The second worm 23 is provided with a shaft shoulder, the shaft shoulder and the end surface of the first worm wheel 6 are jointed with the inner ring of the second bearing 21, and the inner ring of the second bearing 21 is positioned between the shaft shoulder and the first worm wheel 6, so that the axial movement of the second worm 23 is limited, and abnormal sound and abrasion caused by the axial movement of the second worm 23 are prevented.

As shown in fig. 1 and 2, the worm wheel upper cover 4 and the reduction gearbox housing 15 are fixedly connected with the steering gear housing 11, one end of the second worm 23 is mounted on the worm wheel upper cover 4 through a third bearing 24, the other end of the second worm 23 is mounted on the reduction gearbox housing 15 through a second bushing 16, and the first worm wheel 6 is located between the second bearing 21 and the third bearing 24. The inner ring of the third bearing 24 is in interference fit with the second worm 23, and the outer ring of the third bearing 24 is in clearance fit with the upper worm wheel cover 4. The second shaft sleeve 16 supports the second worm 23, the second shaft sleeve 16 is a cylinder with two open ends and a hollow interior, and the second shaft sleeve 16 is sleeved on the second worm 23 and is coaxial with the second worm 23.

As shown in fig. 1 and 2, the outer rings of the worm wheel upper cover 4 and the third bearing 24 are in clearance fit, the worm wheel upper cover 4, the steering gear housing 11 and the reduction gearbox housing 15 form an accommodating space for accommodating the second worm 23, the first worm wheel 6, the second bearing 21, the third bearing 24 and the second bushing 16, the steering gear housing 11 is located between the worm wheel upper cover 4 and the reduction gearbox housing 15, and the reduction gearbox housing 15 is provided with threaded holes matched with the worm wheel upper cover 4 and the steering gear housing 11 for connecting and fixing the worm wheel upper cover 4 and the steering gear housing 11. A second sealing ring 20 is arranged between the reduction gearbox shell 15 and the steering gear shell 11, a third sealing ring 22 is arranged between the worm wheel upper cover 4 and the steering gear shell 11, the first sealing ring, the second sealing ring 20 and the third sealing ring 22 are all O-shaped rings, the second sealing ring 20 is used for sealing between the steering gear shell 11 and the reduction gearbox shell 15, and the third sealing ring 22 is used for sealing between the steering gear shell 11 and the worm wheel upper cover 4.

As shown in fig. 2, the speed reducing mechanism further includes an upper cover plug 5 disposed on the worm wheel upper cover 4, the worm wheel upper cover 4 has a mounting hole for inserting the upper cover plug 5, the mounting hole is a circular hole and the mounting hole is coaxial with the second worm 23, the third bearing 24 is disposed on the inner side of the upper cover plug 5, the upper cover plug 5 and the worm wheel upper cover 4 are in interference fit, a fourth sealing ring 25 is disposed between the upper cover plug 5 and the worm wheel upper cover 4, the fourth sealing ring 25 is an O-shaped ring, the fourth sealing ring 25 is used for sealing between the upper cover plug 5 and the worm wheel upper cover 4, and the protection level of the steering system can be effectively guaranteed.

As shown in fig. 3, the reduction case housing 15 and the mounting base 9 constitute an accommodation space for accommodating the wave elastic washer, the fourth bearing 27, the second worm wheel 28, the fifth bearing 30, the output shaft 31, the skeleton oil seal 32, and the torque angle sensor 33. An output shaft 31 is installed on the reduction gearbox shell 15 through a fourth bearing 27, the output shaft 31 is installed on the installation base 9 through a fifth bearing 30, the installation base 9 is connected with the reduction gearbox shell 15, the inner ring of the fourth bearing 27 is in interference fit with the output shaft 31, and the outer ring of the fifth bearing 30 is in interference fit with the installation base 9.

As shown in fig. 3, the inner ring of the fourth bearing 27 is in interference fit with one end of the output shaft 31, the outer ring of the fourth bearing 27 is installed in the inner cavity of the reduction gearbox housing 15, the outer ring of the fourth bearing 27 is in clearance fit with the reduction gearbox housing 15, the torque angle sensor 33 is fixed on the output shaft 31, the second worm wheel 28 is located between the fourth bearing 27 and the torque angle sensor 33, the second worm wheel 28 is fixed on the output shaft 31 through interference fit, the outer ring of the fifth bearing 30 is installed in the inner cavity of the installation base 9 through interference fit, the output shaft 31 is installed on the fifth bearing 30, and the fifth bearing 30 plays a supporting role.

As shown in fig. 3, a wave-shaped elastic washer is provided between the fourth bearing 27 and the reduction gear casing 15, and the wave-shaped elastic washer is sandwiched between a mounting surface in the reduction gear casing 15 and an outer ring of the fourth bearing 27. The wavy elastic washer has elasticity, a gap is reserved between the end face of the fourth bearing 27 and the mounting surface in the reduction gearbox shell 15 and is used for mounting the wavy elastic washer, the wavy elastic washer is attached between the mounting surface in the reduction gearbox shell 15 and the outer ring of the fourth bearing 27, the mounting surface in the reduction gearbox shell 15 is a plane perpendicular to the axis of the output shaft 31 and is used for supporting the output shaft 31, the wavy elastic washer exerts an elastic acting force on the output shaft 31 along the axial direction through the fourth bearing 27 and prevents the output shaft 31 from moving axially to cause the change of the meshing center distance between the second worm 23 and the second worm wheel 28 to cause abnormal sound, abrasion and damage to a steering system. The wave-shaped elastic washer occupies small space, is convenient to arrange and has good effect.

As shown in fig. 3, the mounting base 9 is fixedly connected with the reduction gearbox housing 15, a fifth sealing ring 29 is arranged between the reduction gearbox housing 15 and the mounting base 9, and the fifth sealing ring 29 is an O-ring. A framework oil seal 32 is arranged between the output shaft 31 and the mounting base 9, and the output shaft 31 penetrates through the mounting base 9 and then extends out towards the outer side of the mounting base 9. The framework oil seal 32 is arranged in the inner cavity of the mounting base 9, and the output shaft 31 is attached to the inner ring of the framework oil seal 32, so that dust and liquid can be prevented from entering the steering system.

As shown in fig. 2, fig. 3, fig. 5, fig. 7 to fig. 9, the utility model discloses an unmanned single wheel turns to electric power steering system for vehicle still includes the torque angle sensor 33 that sets up on output shaft 31, torque angle sensor 33 is located the inside of reducing gear box casing 15, torque angle sensor 33 is connected with sensor pencil 17, be provided with waterproof sealing device on the reducing gear box casing 15, waterproof sealing device includes the sealing plug 34 that contacts with the outer wall of reducing gear box casing 15 and sticiss sealing plug 34 at the pencil clamp plate 14 on reducing gear box casing 15, sealing plug 34 has the hole of dodging that lets sensor pencil 17 pass, set up the radial sealing ring 3404 that contacts with the outer disc of sensor pencil 17 in the hole of dodging, sensor pencil 17 passes radial sealing ring 3404 and the interior disc fixed connection of radial sealing ring 3404 and 34.

As shown in fig. 2 and 7 to 9, the reduction gearbox housing 15 has a mounting hole into which the sealing plug 34 is inserted, the mounting hole is a through hole radially penetrating the side wall of the reduction gearbox housing 15, the mounting hole is a circular hole, and the axis of the mounting hole is perpendicular to the axis of the output shaft 31. The sealing plug 34 is of a revolving body structure, the avoiding hole is a through hole which is formed in the center of the sealing plug 34 in a penetrating mode along the axial direction of the sealing plug 34, the avoiding hole is a round hole, the sealing plug 34 and the mounting hole in the gearbox shell 15 are coaxially arranged, the outer circular surface of the sealing plug 34 is attached to the inner circular surface in the mounting hole, the sealing plug 34 is made of elastic materials, and the sealing plug 34 is an elastic body with elasticity. The radial sealing ring 3404 is of a circular ring structure, the radial sealing ring 3404 and the sealing plug 34 are integrally formed, the radial sealing ring 3404 protrudes from the inner circular surface of the sealing plug 34 in a radial direction towards the avoidance hole, the material of the radial sealing ring 3404 is the same as that of the sealing plug 34, the sensor wire harness 17 passes through the central hole of the radial sealing ring 3404, the inner circular surface of the radial sealing ring 3404 is in contact with the outer circular surface of the sensor wire harness 17, the radial sealing ring 3404 and the sensor wire harness 17 are in interference fit, and the radial sealing ring 3404 plays a sealing role after being mutually extruded. Moreover, the position of the mounting hole on the reduction gearbox housing 15 is aligned with the position of the torque angle sensor 33, the torque angle sensor 33 is located in the axial direction of the mounting hole, the distance between the radial sealing ring 3404 and the first end of the sealing plug 34 is smaller than the distance between the radial sealing ring 3404 and the second end of the sealing plug 34, the first end and the second end of the sealing plug 34 are opposite ends of the sealing plug 34 in the axial direction, the distance between the first end of the sealing plug 34 and the axis of the output shaft 31 is smaller than the distance between the second end of the sealing plug 34 and the axis of the output shaft 31, namely, the position of the radial sealing ring 3404 is close to the end of the sensor wire harness 17 connected with the torque angle sensor 33, so that the sealing performance of the sealing structure cannot be affected even if the sensor wire harness 17 is pulled laterally outside the reduction gearbox.

Preferably, the sealing plug 34 is made of EPDM (ethylene Propylene Diene monomer) material, and the inner circumferential surface of the sealing plug 34 is in contact with the outer circumferential surface of the sensor harness 17.

The number of the radial sealing rings 3404 may be plural, and all the radial sealing rings 3404 are sequentially arranged in the axial direction of the avoiding hole, so that the sealing effect can be further improved. In the present embodiment, as shown in fig. 6 and 7, two radial seal rings 3404 are provided.

As shown in fig. 7 and 8, the sealing plug 34 includes a sealing sleeve body 3401 and a circular flange 3402 that is provided on the sealing sleeve body 3401, the flange 3402 is sandwiched between the harness pressing plate 14 and the reduction gearbox housing 15, an axial sealing ring 3403 that contacts the reduction gearbox housing 15 is provided on the flange 3402, and the axial sealing ring 3403 is a circular ring-shaped structure that extends on the flange 3402 along the entire circumference of the flange 3402. The seal cover body 3401 is a cylindrical structure with openings at two ends and a hollow interior, the avoiding hole is a central hole of the seal cover body 3401, and the radial seal ring 3404 is fixedly connected with the seal cover body 3401. The sealing sleeve body 3401 is inserted into a mounting hole of the reduction gearbox shell 15, the flange 3402 is of a circular ring structure, the flange 3402 is sleeved on the sealing sleeve body 3401 and fixedly connected with the sealing sleeve body 3401, the distance between the flange 3402 and the first end of the sealing sleeve body 3401 (namely the first end of the sealing plug 34) is greater than the distance between the flange 3402 and the second end of the sealing sleeve body 3401 (namely the second end of the sealing plug 34), and the outer diameter of the flange 3402 is greater than the outer diameter of the sealing sleeve body 3401 and the outer diameter of the flange 3402 is greater than the diameter of the mounting hole of the reduction gearbox shell 15. The wire harness pressing plate 14 is located outside the reduction gearbox casing 15, the wire harness pressing plate 14 is provided with a through hole for the sealing sleeve body 3401 to pass through, the flange 3402 is clamped between the wire harness pressing plate 14 and the reduction gearbox casing 15, the axial sealing ring 3403 is arranged on the surface of the flange 3402 contacting with the reduction gearbox casing 15, the axial sealing ring 3403 and the flange 3402 are coaxially arranged, the diameter of the axial sealing ring 3403 is larger than that of the sealing sleeve body 3401, the diameter of the axial sealing ring 3403 is larger than that of the mounting hole, the axial sealing ring 3403 and the sealing plug 34 are integrally formed, and the material of the axial sealing ring 3403 is the same as that of the sealing plug. The wire harness pressing plate 14 applies pressing force to the sealing plug 34 to enable the sealing plug to be tightly pressed in the mounting hole of the reduction gearbox shell 15, the wire harness pressing plate 14 extrudes the sealing plug 34, meanwhile, the axial sealing ring 3403 and the reduction gearbox shell 15 are extruded to form a sealing strip, axial sealing is achieved, therefore, the sealing effect at the mounting hole of the reduction gearbox shell 15 can be further improved, and the inner cavity of the reduction gearbox shell 15 is isolated from the external environment.

As shown in fig. 8 and 9, the harness retainer 14 is attached to the reduction gear case 15 by bolts 35, the harness retainer 14 has bolt holes through which the bolts 35 pass, and the reduction gear case 15 has female screw holes through which the bolts 35 are inserted. The wire harness pressing plate 14 comprises a pressing part 1401 and a mounting part 1402, the pressing part 1401 is in contact with a flange 3402 and the reduction box shell 15, the flange 3402 is clamped between the pressing part 1401 and the reduction box shell 15, a bolt hole for allowing a bolt 35 to penetrate through is arranged on the pressing part 1401, and a through hole for allowing the sealing sleeve body 3401 to penetrate through is arranged in the center of the pressing part 1401. The mounting portion 1402 is fixedly connected with the pressing portion 1401, the mounting portion 1402 extends towards the outer side of the reduction gearbox shell 15, the mounting portion 1402 is used for providing a mounting point for mounting the sensor wiring harness 17, and the sensor wiring harness 17 is mounted on the mounting portion 1402 through a buckle, so that the sensor wiring harness 17 is arranged according to a set path, and random bending deformation of the sensor wiring harness 17 is avoided.

The sealing structure is arranged at the mounting hole of the reduction gearbox shell 15, so that the sealing structure is simplified, the requirement of axial and radial sealing is met by one part, the sealing performance is reliable, and the sealing effect of a wire harness part can be effectively guaranteed; and the part cost is saved, and the assembly manufacturability is better.

As shown in fig. 1 to 6, the steering controller is fixedly arranged on the reduction gearbox housing 15, the power-assisted motor 1 is connected with a power output end 1903 of the steering controller through a connector, the steering controller is electrically connected with the power-assisted motor 1 and the torque angle sensor 33, and the sensor wire harness 17 is connected with the steering controller. The signal input end 1901 of the steering controller is connected with a signal unit of the unmanned single-wheel steering vehicle through a CAN bus, the power input end 1904 of the steering controller is connected with a storage battery of the unmanned single-wheel steering vehicle through a wiring harness, and the storage battery is a 9-16V direct-current power supply.

The electric power steering system for the unmanned single-wheel steering vehicle adopts a pure wire control mode to realize accurate power steering; the steering controller receives a steering control signal of the unmanned single-wheel steering vehicle, integrates the steering related boundary conditions of the unmanned single-wheel steering vehicle, calculates a driving angle and a driving torque required by actual steering of the unmanned single-wheel steering vehicle, drives the power-assisted motor 1 by proper current voltage, and enables the output shaft 31 to rotate, so that active steering of the unmanned single-wheel steering vehicle is realized, and meanwhile, accurate control of the steering angle of the unmanned single-wheel steering vehicle is realized through closed-loop PI adjustment of a steering angle signal fed back by the torque angle sensor 33 in real time.

In this embodiment, the unmanned single-wheel steerable vehicle is a small-sized logistics transfer vehicle, a micro-sized logistics transfer vehicle or a sweeper.

As shown in fig. 1 and 10, the mounting base 9 is fixedly connected to a vehicle body of the unmanned one-wheel steered vehicle, the output shaft 31 is in a vertical state, a key groove for mounting the parallel key 8 is formed in an end portion of the output shaft 31, the output shaft 31 is connected to a steering bracket 36 of the unmanned one-wheel steered vehicle through the parallel key 8, a steering wheel 37 is arranged on the steering bracket 36, the steering wheel 37 is rotatably connected to the steering bracket 36 through a rotating shaft, and an axis of the rotating shaft is a horizontal line. When the output shaft 31 rotates, the steering bracket 36 and the steering wheel 37 are driven to rotate synchronously, so that the steering of the unmanned one-wheel steering vehicle is realized.

The utility model discloses an unmanned single wheel turns to electric power assisted steering system for vehicle has compact structure, simple, whole small, with low costs, the steering system fault rate is low, and no angular distortion risk turns to accurate, advantage that intelligent degree is high.

The invention has been described above by way of example with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited by the above-described manner. Various insubstantial improvements are made by adopting the method conception and the technical proposal of the utility model; or without improvement, the above conception and technical solution of the present invention can be directly applied to other occasions, all within the protection scope of the present invention.

Claims (10)

1. Unmanned single wheel turns to electric power assisted steering system for vehicle, including helping hand motor, reduction gears and output shaft, its characterized in that: the speed reducing mechanism comprises a first worm, a second worm, a first worm wheel and a second worm wheel, wherein the first worm and the second worm are connected with the power-assisted motor, the first worm wheel is arranged on the second worm and meshed with the first worm, and the second worm wheel is arranged on the output shaft and meshed with the second worm.

2. The electric power steering system for the unmanned one-wheel-steered vehicle of claim 1, wherein: the speed reducing mechanism comprises a steering engine shell, the first worm is installed in the steering engine shell through a first bearing and a first shaft sleeve, a bearing pressing plate used for axially limiting the first bearing is arranged in the steering engine shell, and an inner ring of the first bearing is in interference fit with the first worm.

3. The electric power steering system for the unmanned one-wheel-steered vehicle of claim 2, wherein: the second worm is installed on the steering gear shell through a second bearing, the inner ring of the second bearing is in interference fit with the second worm, and the end face of the first worm wheel is attached to the inner ring of the second bearing.

4. The electric power steering system for the unmanned one-wheel-steered vehicle of claim 3, wherein: the reduction gears still include with gear box casing and the worm wheel upper cover that the steering gear casing is connected, the steering gear casing is located between gear box casing and the worm wheel upper cover, the one end of second worm is passed through the third bearing and is installed on the worm wheel upper cover, and the other end of second worm passes through the second bushing and installs on the gear box casing, first worm wheel is located between second bearing and the third bearing.

5. The electric power steering system for the unmanned one-wheel-steered vehicle according to claim 4, wherein: the inner ring of the third bearing is in interference fit with the second worm, and the outer ring of the third bearing is in clearance fit with the upper cover of the worm wheel.

6. The electric power steering system for the unmanned one-wheel-steered vehicle according to claim 4, wherein: the steering gear box is characterized in that a first sealing ring is arranged between the steering gear box shell and the power-assisted motor, a second sealing ring is arranged between the reduction gear box shell and the steering gear box shell, a third sealing ring is arranged between the worm gear upper cover and the steering gear box shell, and the first sealing ring, the second sealing ring and the third sealing ring are all O-shaped rings.

7. The electric power steering system for the unmanned one-wheel-steered vehicle according to any one of claims 4 to 6, wherein: the output shaft is installed on the speed reduction box shell through a fourth bearing, the output shaft is installed on the installation base through a fifth bearing, the installation base is connected with the speed reduction box shell, the inner ring of the fourth bearing is in interference fit with the output shaft, and the outer ring of the fifth bearing is in interference fit with the installation base.

8. The electric power steering system for the unmanned one-wheel-steered vehicle of claim 7, wherein: and a wave-shaped elastic gasket is arranged between the fourth bearing and the shell of the reduction gearbox and is clamped between the mounting surface in the shell of the reduction gearbox and the outer ring of the fourth bearing.

9. The electric power steering system for the unmanned one-wheel-steered vehicle of claim 7, wherein: the gearbox shell with set up the fifth sealing washer between the installation base, the fifth sealing washer is O type circle, set up the skeleton oil blanket between output shaft and the installation base.

10. The electric power steering system for the unmanned one-wheel-steered vehicle according to any one of claims 4 to 6, wherein: still including set up in output epaxial moment of torsion angle sensor, moment of torsion angle sensor are located the inside of reducing gear box casing, moment of torsion angle sensor is connected with the sensor pencil, is provided with waterproof sealing device on the reducing gear box casing, and waterproof sealing device includes the sealing plug that contacts with the outer wall of reducing gear box casing and sticiss the pencil clamp plate on the reducing gear box casing with the sealing plug, and the sealing plug has the hole of dodging that lets the sensor pencil pass.

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