Single wheel steering mechanism

Abstract

The present invention provides a single-wheel steering mechanism, comprising: a driving part; a directional wheel assembly, arranged below the driving part; a steering shaft, arranged vertically on one side of the driving part; the top end of the steering shaft is connected to the driving part, and the bottom end of the steering shaft is used to be connected to the directional wheel assembly; a control part, electrically connected to the driving part; a limit module, comprising a cam sleeved on the steering shaft and a limit member arranged outside the cam; the cam is connected to the steering shaft; the limit member is electrically connected to the driving part, and when the rotation angle of the steering shaft exceeds a threshold, the cam squeezes the limit member, thereby causing the limit member to be triggered. The cam is connected to the steering shaft, so that the cam can rotate with the steering shaft. When the rotation angle of the steering shaft exceeds the threshold, the cam squeezes the limit member, thereby causing the limit member to be triggered. In addition, since the limit member is electrically connected to the driving part, when the limit member is triggered, the control part changes the output of the driving part, so that the steering shaft can rotate back, and an excessive steering angle can be avoided.

Description

Technical Field

[0001] The invention relates to the field of steering mechanisms, in particular to a single-wheel steering mechanism. Background Art

[0002] Single-wheel steering mechanisms are usually installed on self-driving vehicles to adjust the direction of the vehicle. Traditional steering mechanisms are usually used in driving vehicles, mainly driven by human power, and some have electric or hydraulic power-assist mechanisms. This type of traditional steering mechanism requires human power, has an incompact structure, has a small steering force, and has poor scalability, making it difficult to apply to self-driving and electronically controlled driving equipment.

[0003] In automatic navigation driving equipment, the steering mechanism is an essential core component. The steering force, steering accuracy and steering angle provided by the steering mechanism affect various indicators such as equipment load, speed and flexibility. Existing single-wheel steering mechanisms usually do not have a limit function, which may cause the vehicle to turn too far, which may lead to safety accidents.

[0004] Therefore, the prior art has defects and needs to be improved and developed. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, an object of the present invention is to provide a single-wheel steering mechanism, aiming to solve the problem that the single-wheel steering mechanism in the prior art does not have a limiting function.

[0006] A technical solution adopted by the present invention to solve the technical problem is as follows:

[0007] A single-wheel steering mechanism, comprising:

[0008] Drive unit;

[0009] A directional wheel assembly is arranged below the driving part;

[0010] A steering shaft is vertically arranged on one side of the driving part; the top end of the steering shaft is drivingly connected to the driving part, and the bottom end of the steering shaft is drivingly connected to the directional wheel assembly;

[0011] A control unit, electrically connected to the driving unit;

[0012] The limit module includes a cam sleeved on the steering shaft and a limit piece arranged on the outside of the cam; the cam is connected to the steering shaft; the limit piece is electrically connected to the driving part, and when the rotation angle of the steering shaft exceeds a threshold value, the cam squeezes the limit piece, thereby causing the limit piece to be triggered.

[0013] Furthermore, the limiting member includes a limiting body, a compression body and a roller;

[0014] The limiting body is fixedly arranged; the limiting body is electrically connected to the control unit;

[0015] The compression body is located on a side of the limiting body facing the cam, and the compression body is arranged along the radial direction of the steering shaft; the compression body is connected to the limiting body, so as to transmit the compression amount to the limiting body;

[0016] The roller is located on the side of the compression body facing the cam, the roller is rotatably connected to the compression body, and the axis of the roller is parallel to the axis of the steering shaft; when the edge of the cam contacts the roller, the roller rotates.

[0017] Further, the edge of the circumferential side of the cam includes a first contour, a second contour and a third contour; the second contour is located between the first contour and the third contour, and two ends of the second contour are respectively connected to the first contour and the third contour;

[0018] The diameter of the first profile is constant at a first distance; when the directional wheel assembly travels in a straight line, the roller is located outside the first profile;

[0019] The diameter of the second contour gradually increases from the first distance to the second distance; when the directional wheel assembly rotates, the position of the roller gradually changes from the outside of the first contour to the outside of the second contour;

[0020] When the rotation angle of the directional wheel assembly reaches a threshold value, the roller is located at the connection point of the first contour and the second contour, and the roller contacts the cam, thereby triggering the limiter;

[0021] The diameter of the third contour is constant at the second distance.

[0022] Furthermore, the maximum compression amount of the compression body is greater than the compression amount of the compression body when the roller is at the connection point of the first contour and the second contour.

[0023] Further, the driving unit includes a motor, a synchronous pulley set and a bevel gear set;

[0024] The motor is arranged above the directional wheel assembly;

[0025] The synchronous belt pulley set is arranged on the peripheral side of the motor, and the input end of the synchronous belt pulley set is drivingly connected to the output end of the motor;

[0026] The bevel gear set is arranged on the circumferential side of the motor, and the input end of the bevel gear set is drivingly connected to the output end of the synchronous pulley set.

[0027] Furthermore, the synchronous pulley set includes a first pulley drivingly connected to the output end of the motor, a second pulley arranged on a radial side of the first pulley, and a synchronous belt sleeved on the first pulley and the second pulley.

[0028] Furthermore, the electric single-wheel steering mechanism also includes a tensioning wheel, a base plate, a mounting plate and a limit pin;

[0029] The tensioning wheel is arranged between the first pulley and the second pulley;

[0030] The bottom plate is located on one side of the tension wheel in the axial direction, and the bottom plate is connected to the tension wheel;

[0031] The mounting plate is arranged on a side of the bottom plate away from the tensioning wheel; a waist-shaped hole is provided on the side of the mounting plate facing the bottom plate, and the waist-shaped hole is arranged in the vertical direction;

[0032] The limiting pin is movably arranged in the waist-shaped hole up and down, and one end of the limiting pin facing the bottom plate is connected to the bottom plate.

[0033] Further, the bevel gear set includes a first bevel gear drivingly connected to the second pulley and a second bevel gear meshing with the first bevel gear; the axis of the second bevel gear is vertically arranged;

[0034] The single-wheel steering mechanism further comprises a transmission shaft; the axis of the transmission shaft is perpendicular to the axis of the second bevel gear, and the second pulley and the first bevel gear are both disposed on the transmission shaft.

[0035] Furthermore, the single-wheel steering mechanism further includes a fixing plate arranged above the directional wheel assembly;

[0036] The motor, the synchronous pulley set and the bevel gear set are all arranged on the fixing plate.

[0037] Furthermore, the single-wheel steering mechanism also includes a magnetic navigation module for detecting a magnetic field;

[0038] The magnetic navigation module is arranged in front of the directional wheel assembly, and the magnetic navigation module is electrically connected to the control unit.

[0039] It can be seen from the above technical solution that the present invention has at least the following advantages and positive effects:

[0040] In the present invention, the steering shaft is arranged on one side of the driving unit, and the top end of the steering shaft is drivingly connected to the driving unit, and the bottom end of the steering shaft is used to be drivingly connected to the directional wheel assembly to drive the directional wheel assembly to rotate. The limiting module includes a cam sleeved on the steering shaft and a limiting member arranged on the outside of the cam, and the cam is connected to the steering shaft so that the cam can rotate with the steering shaft. When the rotation angle of the steering shaft exceeds the threshold, the cam squeezes the limiting member, thereby causing the limiting member to be triggered. In addition, since the limiting member is electrically connected to the driving unit, when the limiting member is triggered, the control unit changes the output of the driving unit, so that the steering shaft can be rotated back, and the steering angle can be avoided to be too large. Now, for the single-wheel steering mechanism in the prior art, the problem of excessive steering angle can be avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a structural schematic diagram of a single-wheel steering mechanism in one embodiment of the present invention.

[0042] Figure 2 It is a schematic structural diagram of a position limiting member in one embodiment of the present invention.

[0043] Figure 3 Schematic diagram of the structure of a cam in one embodiment of the present invention.

[0044] Figure 4 1 is a side view of a single-wheel steering mechanism according to an embodiment of the present invention.

[0045] Figure 5 It is an axonometric view of a single-wheel steering mechanism in one embodiment of the present invention.

[0046] Figure 6 1 is a top view of a single-wheel steering mechanism according to an embodiment of the present invention.

[0047] Figure 7 2 is a cross-sectional view of a single-wheel steering mechanism according to an embodiment of the present invention.

[0048] Description of reference numerals:

[0049] 100. Single wheel steering mechanism;

[0050] 1. Motor; 2. Synchronous pulley set; 21. First pulley; 22. Second pulley; 3. Bevel gear set; 31. First bevel gear; 32. Second bevel gear; 41. Steering shaft; 42. Fixing plate; 43. Bushing; 44. Tapered roller bearing; 45. Transmission shaft; 5. Directional wheel assembly; 51. Wheel; 52. Rib plate; 53. Connecting plate; 54. Mounting seat; 61. Bottom plate; 62. Mounting plate; 63. Waist-shaped hole; 64. Tensioning wheel; 65. Magnetic navigation module; 66. Bracket; 7. Limiting member; 71. Limiting body; 72. Compression body; 73. Roller; 8. Cam; 81. First profile; 82. Second profile; 83. Third profile. DETAILED DESCRIPTION

[0051] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0052] See also Figure 1 In one embodiment of the present invention, a single-wheel steering mechanism 100 is provided, which includes a steering shaft 41 arranged vertically, a driving unit arranged on one side of the steering shaft 41, a directional wheel assembly 5 arranged below the driving unit, a control unit (not shown) electrically connected to the driving unit, and a limit module located on the peripheral side of the steering shaft 41. The directional wheel assembly 5 can be oriented by being deflected by force. The driving unit is used to provide the steering shaft 41 with the force required for rotation. The steering shaft 41 is roughly cylindrical and arranged vertically. The top end of the steering shaft 41 is connected to the driving unit for driving, and the bottom end of the steering shaft 41 is connected to the directional wheel assembly 5 for driving, so that the steering shaft 41 can drive the directional wheel assembly 5 to rotate after the steering shaft 41 rotates. The control unit is used to control the driving unit to change the direction and magnitude of the torque output by the driving unit, so that the directional wheel assembly 5 rotates clockwise or counterclockwise. In this embodiment, the control unit is a programmable logic controller, but the control unit is not limited to a programmable logic controller. Exemplarily, the control unit may also be a single chip microcomputer.

[0053] The limit module includes a cam 8 sleeved on the steering shaft 41 and a limit member 7 arranged on the outside of the cam 8. The cam 8 is roughly disc-shaped, and the axis of the cam 8 coincides with the axis of the steering shaft 41. The cam 8 is connected to the steering shaft 41 so that the cam 8 can rotate with the steering shaft 41. When the rotation angle of the steering shaft 41 exceeds the threshold, the cam 8 squeezes the limit member 7, thereby causing the limit member 7 to be triggered. The threshold refers to the preset maximum steering angle, which is set manually. Since the limit member 7 is electrically connected to the drive unit, when the limit member 7 is triggered, the control unit changes the output of the drive unit, so that the steering shaft 41 can be rotated back, and the steering angle can be avoided to be too large. Now for the single-wheel steering mechanism in the prior art, the problem of excessive steering angle can be avoided.

[0054] Specifically, see Figures 1 to 3 As a specific implementation of this embodiment, the limit member 7 is a ball plunger type limit switch, and the limit member 7 includes a limit body 71, a compression body 72 and a roller 73. The limit body 71 is roughly block-shaped, and the limit body 71 is fixedly arranged. The limit body 71 is electrically connected to the control unit to transmit an electrical signal to the control unit. The compression body 72 is located on the side of the limit body 71 facing the cam 8, and the compression body 72 is arranged along the radial direction of the steering shaft 41, that is, after the compression body 72 is subjected to the radial pressure from the steering shaft 41, the compression body 72 can be compressed. The compression body 72 is connected to the limit body 71, so as to transmit the compression amount to the limit body 71. The roller 73 is located on the side of the compression body 72 facing the cam 8, and the roller 73 is rotationally connected to the compression body 72, and the axis of the roller 73 is parallel to the axis of the steering shaft 41, so when the roller 73 contacts the side of the cam 8, the roller 73 can rotate along its own axis.

[0055] Since the cam 8 rotates together with the steering shaft 41, when the rotation angle of the steering shaft 41 exceeds a threshold value, the cam 8 squeezes the compression body 72, thereby triggering the limit member 7. At the same time, the limit member 7 transmits an electrical signal to the control unit, and the control unit changes the output direction of the drive unit to form a closed-loop feedback system, thereby preventing the steering angle of the single-wheel steering mechanism 100 from being too large.

[0056] Specifically, see Figure 3 As a specific implementation method of this embodiment, the edge of the circumferential side of the cam 8 includes a first profile 81, a second profile 82 and a third profile 83, the second profile 82 is located between the first profile 81 and the third profile 83, and the two ends of the second profile 82 are respectively connected to the first profile 81 and the third profile 83.

[0057] The first profile 81 is Figure 3 In the ab segment in the figure, the diameter of the first profile 81 is constant at the first distance L1. When the directional wheel assembly 5 is traveling in a straight line, that is, when the steering shaft 41 is not rotating, the roller 73 is located outside the first profile 81. At this time, the roller 73 is spaced from the edge of the cam 8 or the roller 73 is in contact with the edge of the cam 8 but without the action of force. In this embodiment, the roller 73 is in contact with the edge of the cam 8 but without the action of force, which can prevent the compression body 72 from being squeezed for a long time and causing damage.

[0058] The second profile 82 is Figure 3 In the bc section, the diameter of the second profile 82 gradually increases from the first distance L1 to the second distance L2. When the directional wheel assembly 5 rotates, the position of the roller 73 gradually changes from the outside of the first profile 81 to the outside of the second profile 82, that is, the cam 8 gradually rotates relative to the roller 73 to the bc section.

[0059] The third profile 83 is Figure 3 In the cd segment, the diameter of the third profile 83 is constant at the second distance L2. When the angle of rotation of the directional wheel assembly 5 reaches a threshold value, the roller 73 is located at the connection point of the first profile 81 and the second profile 82, that is, the connection point of the second profile 82 and the third profile 83 is the preset maximum steering angle. When the second profile 82 of the cam 8 just rotates to the connection point of the first profile 81 and the second profile 82, there is an interaction force between the roller 73 and the cam 8, but the limiter 7 is not triggered at this time. When the cam 8 rotates to the connection point of the second profile 82 and the third profile 83, the limiter 7 is triggered, and the control unit starts to adjust the output of the drive unit to avoid excessive rotation angle.

[0060] In this embodiment, two limit members 7 are provided, and the two limit members 7 are symmetrically distributed along the axis of the steering shaft 41. Correspondingly, the edge of the cam 8 is symmetrically divided into two left and right parts along the perpendicular bisector of the line connecting the two limit members 7. The edges of the left and right parts are both provided with the first contour 81, the second contour 82 and the third contour 83, and the first contour 81, the second contour 82 and the third contour 83 on the left and right cams 8 are all symmetrically distributed along the perpendicular bisector of the line connecting the two limit members 7, so that the steering shaft 41 has a limiting function when rotating clockwise or counterclockwise.

[0061] The connection between the first contour 81 and the second contour 82 has a smooth transition, which can prevent the roller 73 from being impacted when it changes from being in contact with the first contour 81 to being in contact with the second contour 82, and can make the steering process smoother.

[0062] See also Figure 1 , the angle between the roller 73 and the directional wheel assembly 5 is γ, the angle of the arc segment corresponding to the first contour 81 is α, and the angle of the arc segment corresponding to the second contour 82 is β. γ is smaller than α, so that when the directional wheel assembly 5 is traveling in the direction, the roller 73 is located outside the first contour 81. Usually 45°≤α+β-γ≤90°, that is, the threshold value of the steering angle of the steering shaft 41 is approximately 45° to 90°. However, the steering angle of the steering shaft 41 is not limited to 45° to 90°. In a specific embodiment, γ=45°, α=90°, β=45°.

[0063] Specifically, see Figures 1 to 3 As a specific implementation method of this embodiment, the maximum compression amount of the compression body 72 is greater than the compression amount of the compression body 72 when the roller 73 is at the connection point of the first profile 81 and the second profile 82. Therefore, when the limit member 7 fails, even if the rotation angle of the steering shaft 41 exceeds the threshold, the limit member 7 is not compressed and damaged, which can extend the service life of the limit member 7.

[0064] Specifically, see Figures 4 to 6As a specific implementation of this embodiment, the driving unit includes a motor 1, a synchronous pulley set 2 and a bevel gear set 3. The motor 1 is arranged above the directional wheel assembly 5, and the motor 1 is the power source of the single-wheel steering mechanism 100. The motor 1 is a stepping motor or a servo motor, so as to adjust the speed and torque output by the motor 1. For the convenience of description, the motor 1 is now taken as a reference, the length direction of the motor 1 is recorded as the length direction, the width direction of the motor 1 is recorded as the width direction, and the height direction of the motor 1 is recorded as the height direction or the vertical direction. The synchronous pulley set 2 is arranged along the width direction, and the synchronous pulley set 2 is located on one side of the output end of the motor 1. The input end of the synchronous pulley set 2 is drivingly connected to the output end of the motor 1 to output the torque of the motor 1. The input end of the bevel gear set 3 is drivingly connected to the output end of the synchronous pulley set 2, and the output end of the bevel gear set 3 is drivingly connected to the steering shaft 41 to drive the steering shaft 41 to rotate. The steering shaft 41 is used to connect with the directional wheel assembly 5 to drive the directional wheel assembly 5 to rotate. Compared with the connecting rod transmission used in the prior art, a more accurate steering angle can be output. The output end of the synchronous pulley set 2 is drivingly connected with the input end of the bevel gear set 3, so that the single-wheel steering mechanism 100 can transmit a larger torque. In addition, the steering angle can be accurately controlled by adjusting the transmission ratio of the synchronous pulley set 2 and the bevel gear set 3. In addition, by adjusting the transmission ratio, the steering shaft 41 can output a larger torque, so that the steering mechanism has a wider range of use.

[0065] Specifically, see Figures 4 to 6 As a specific implementation of this embodiment, the synchronous pulley set 2 includes a first pulley 21 drivingly connected to the output end of the motor 1, a second pulley 22 arranged on a radial side of the first pulley 21, and a synchronous belt (not shown) sleeved on the first pulley 21 and the second pulley 22. The first pulley 21 is the input end of the synchronous pulley set 2, and the second pulley 22 is the output end of the synchronous pulley set 2. The diameter of the first pulley 21 is smaller than the diameter of the second pulley 22, that is, the synchronous pulley set 2 can play a deceleration role and can accurately adjust the output speed of the motor 1.

[0066] The synchronous belt, the first pulley 21 and the second pulley 22 are all provided with teeth, and the teeth on the synchronous belt mesh with the teeth on the first pulley 21 and the teeth on the second pulley 22. The first pulley 21 is installed on the output shaft of the motor 1 and rotates with the output shaft of the motor 1. The rotation of the first pulley 21 drives the synchronous belt to rotate, and the rotation of the synchronous belt drives the second pulley 22 to rotate, so that the torque output by the motor 1 can be output through the synchronous pulley group 2. When the synchronous pulley group 2 is transmitted, the transmission ratio is accurate and there is no slippage, which can improve the steering accuracy. In addition, the synchronous pulley group 2 has buffering and shock absorption capabilities, so that the single-wheel steering mechanism 100 can operate stably.

[0067] Specifically, see Figures 4 to 6 As a specific implementation of this embodiment, the single-wheel steering mechanism 100 further includes a tensioning wheel 64, a bottom plate 61 and a mounting plate 62. The tensioning wheel 64 is arranged between the first pulley 21 and the second pulley 22. The bottom plate 61 is located on one side of the axial direction of the tensioning wheel 64, and the bottom plate 61 is connected to the tensioning wheel 64. Specifically, the tensioning wheel 64 is rotatably mounted on the side of the bottom plate 61 facing the motor 1 through a rotating shaft. A stop pin is convexly provided on the side of the bottom plate 61 away from the tensioning wheel 64, and the stop pin is roughly cylindrical.

[0068] The mounting plate 62 is arranged on the side of the bottom plate 61 away from the tensioning wheel 64. The mounting plate 62 is provided with a waist-shaped hole 63 on the side facing the bottom plate 61, and the waist-shaped hole 63 is arranged in the vertical direction. The limit pin is movably arranged in the waist-shaped hole 63, that is, the limit pin is interference-fitted with the waist-shaped hole 63 and thus clamped in the waist-shaped hole 63. By adjusting the position of the limit pin in the waist-shaped hole 63, the height of the bottom plate 62 is adjusted, and then the height of the tensioning wheel 64 is adjusted. The setting of the tensioning wheel 64 can make the synchronous belt tensioned, and can prevent the synchronous belt pulley set 2 from changing the transmission ratio due to the loosening of the synchronous belt. In addition, the tensioning wheel 64 has different installation heights. By adjusting the position of the tensioning wheel 64, the synchronous belt can be always in a tensioned state under the action of the tensioning wheel 64.

[0069] Specifically, see Figures 4 to 6As a specific implementation of this embodiment, the bevel gear set 3 includes a first bevel gear 31 drivingly connected to the second pulley 22 and a second bevel gear 32 meshing with the first bevel gear 31. The first bevel gear 31 is the input end of the bevel gear set 3, and the first bevel gear 31 is arranged parallel to the second pulley 22. The second bevel gear 32 is the input end of the bevel gear set 3, and the axis of the second bevel gear 32 is arranged vertically. The second bevel gear 32 is drivingly connected to the steering shaft 41 to change the rotation angle of the directional wheel assembly 5 through the steering of the steering shaft 41. The number of teeth of the second bevel gear 32 is greater than the number of teeth of the first bevel gear 31, that is, the bevel gear set 3 can play a deceleration role, and the primary deceleration of the synchronous pulley set 2 cooperates with the secondary deceleration of the bevel gear set 3, which can accurately adjust the steering angle, so that the single-wheel steering mechanism 100 has a higher steering accuracy.

[0070] The first bevel gear 31 and the second bevel gear 32 are both helical bevel gears. Helical bevel gears have good meshing performance and smooth transmission, which can make the single-wheel steering mechanism 100 have the advantage of smooth operation.

[0071] Specifically, see Figure 5 and Figure 7 As a specific implementation of this embodiment, the single-wheel steering mechanism 100 further includes a transmission shaft 45, which is substantially cylindrical. The axis of the transmission shaft 45 is perpendicular to the axis of the second bevel gear 32, and the second pulley 22 and the first bevel gear 31 are both disposed on the transmission shaft 45 to achieve synchronous rotation of the second pulley 22 and the first bevel gear 31.

[0072] Specifically, see Figure 5 As a specific implementation of this embodiment, the motor 1 is arranged horizontally, that is, the motor 1 is arranged flat, so that the motor 1 and the synchronous pulley set 2 are closely arranged, and the structure of the single-wheel steering mechanism 100 is more compact. The output shaft of the motor 1 is arranged toward the synchronous pulley set 2, which makes it easy for the synchronous pulley set 2 to connect with the motor 1 to output the torque of the motor 1.

[0073] Specifically, see Figure 4As a specific implementation of this embodiment, the single-wheel steering mechanism 100 further includes a directional wheel assembly 5, which is arranged below the motor 1, and is drivingly connected to one end of the steering shaft 41 away from the motor 1. Specifically, the directional wheel assembly 5 includes a vertically arranged wheel 51, ribs 52 arranged on both sides of the wheel 51, and a connecting plate 53 arranged above the wheel 51. The wheel 51 is connected to the two ribs 52 using a rotating shaft, so that the wheel 51 can rotate. The two ends of the connecting plate 53 are respectively connected to the two ribs 52.

[0074] A mounting seat 54 is also provided at the bottom of the steering shaft 41. The mounting seat 54 is roughly plate-shaped, and is located between the steering shaft 41 and the connecting plate 53. The mounting seat 54 is welded to the bottom end of the steering shaft 41. The mounting seat 54 is connected to the connecting plate 53 by bolts to achieve the connection between the mounting seat 54 and the directional wheel assembly 5. When the steering shaft 41 rotates, the steering shaft 41 drives the mounting seat 54 and the directional wheel assembly 5 to rotate to achieve the driving connection between the steering shaft 41 and the directional wheel assembly 5. Since the mounting seat 54 is connected to the connecting plate 53 of the directional wheel assembly 5 by bolts, the directional wheel assembly 5 has the advantage of being easy to install and disassemble.

[0075] The cam 8 is mounted on the upper surface of the mounting seat 54 by means of bolts.

[0076] Specifically, see Figure 4 As a specific implementation of this embodiment, the single-wheel steering mechanism 100 further includes a fixing plate 42 disposed above the directional wheel assembly 5. The fixing plate 42 is generally plate-shaped and is a basic mounting platform. The motor 1, the synchronous pulley set 2 and the bevel gear set 3 are all disposed on the fixing plate 42. The stopper 7 is fixed to the bottom surface of the fixing plate 42 by bolts.

[0077] Specifically, see Figure 7 As a specific implementation of this embodiment, the single-wheel steering mechanism 100 further includes a tapered roller bearing 44 and a sleeve 43. The sleeve 43 is roughly cylindrical, and the sleeve 43 is sleeved on the steering shaft 41, and the sleeve 43 is penetrated on the fixing plate 42, and the sleeve 43 is fixedly connected to the fixing plate 42 to protect the steering shaft 41 inside. The tapered roller bearing 44 is arranged in the sleeve 43 and sleeved on the steering shaft 41. The tapered roller bearing 44 has a higher pressure resistance, so that the single-wheel steering mechanism 100 can be applied to heavy-duty automatic navigation driving equipment.

[0078] Specifically, see Figure 4 As a specific implementation of this embodiment, the single-wheel steering mechanism 100 also includes a magnetic navigation module 65 for detecting a magnetic field. The magnetic navigation module 65 is arranged in front of the directional wheel assembly 5. Specifically, the single-wheel steering mechanism 100 also includes a bracket 66 for mounting the magnetic navigation module 65, and the top of the bracket 66 is connected to the connecting plate 53. The middle part of the bracket 66 is in a vertical state and is located in front of the wheel 51. The bottom end of the bracket 66 is bent horizontally for mounting the magnetic navigation module 65. The magnetic navigation module 65 is electrically connected to the control unit. The magnetic navigation module 65 detects the embedded magnetic field in the use environment through a built-in magnetic navigation sensor (not shown in the figure), and feeds back the detected magnetic field signal to the control unit. The control unit adjusts the output of the motor 1 in real time according to the received signal to control the rotation angle of the directional wheel assembly 5 to achieve automatic navigation.

[0079] In summary, the present invention provides a single-wheel steering mechanism 100. In the present invention, the steering shaft 41 is arranged on one side of the driving unit, and the top end of the steering shaft 41 is connected to the driving unit, and the bottom end of the steering shaft 41 is used to be connected to the directional wheel assembly 5 to drive the directional wheel assembly 5 to rotate. The limit module includes a cam 8 sleeved on the steering shaft 41 and a limiter 7 arranged outside the cam 8. The cam 8 is connected to the steering shaft 41 so that the cam 8 can rotate with the steering shaft 41. When the rotation angle of the steering shaft 41 exceeds the threshold, the cam 8 squeezes the limiter 7, thereby causing the limiter 7 to be triggered. In addition, since the limiter 7 is electrically connected to the driving unit, when the limiter 7 is triggered, the control unit changes the output of the driving unit, so that the steering shaft 41 can be rotated back, and the steering angle can be avoided to be too large. Now, for the single-wheel steering mechanism in the prior art, the problem of too large a steering angle can be avoided.

[0080] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0081] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0082] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0083] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0084] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0085] Of course, the description of the above-mentioned embodiments of the present invention is relatively detailed, but it cannot be understood as limiting the scope of protection of the present invention. The present invention may also have many other implementation methods. Based on this implementation method, other implementation methods obtained by ordinary technicians in this field without any creative work all belong to the scope of protection of the present invention. The scope of protection of the present invention shall be based on the attached claims.

Claims

1. A single-wheel steering mechanism, characterized in that: include: Drive unit; A directional wheel assembly is arranged below the driving part; A steering shaft is vertically arranged on one side of the driving part; the top end of the steering shaft is drivingly connected to the driving part, and the bottom end of the steering shaft is drivingly connected to the directional wheel assembly; A control unit, electrically connected to the driving unit; A limit module, comprising a cam sleeved on the steering shaft and a limit piece arranged outside the cam; the cam is connected to the steering shaft; the limit piece is electrically connected to the driving unit, and when the rotation angle of the steering shaft exceeds a threshold value, the cam squeezes the limit piece, thereby causing the limit piece to be triggered; The limiting member includes a limiting body, a compression body and a roller; The limiting body is fixedly arranged; the limiting body is electrically connected to the control unit; The compression body is located on a side of the limiting body facing the cam, and the compression body is arranged along the radial direction of the steering shaft; the compression body is connected to the limiting body, so as to transmit the compression amount to the limiting body; The roller is located on a side of the compression body facing the cam, the roller is rotatably connected to the compression body, and the axis of the roller is parallel to the axis of the steering shaft; when the edge of the cam contacts the roller, the roller rotates; The driving unit includes a motor, a synchronous pulley set and a bevel gear set; The motor is arranged above the directional wheel assembly; The synchronous belt pulley set is arranged on the peripheral side of the motor, and the input end of the synchronous belt pulley set is drivingly connected to the output end of the motor; The bevel gear set is arranged on the circumferential side of the motor, and the input end of the bevel gear set is drivingly connected to the output end of the synchronous pulley set.

2. The single-wheel steering mechanism according to claim 1, characterized in that: The edge of the circumferential side of the cam includes a first contour, a second contour and a third contour; the second contour is located between the first contour and the third contour, and two ends of the second contour are respectively connected to the first contour and the third contour; The diameter of the first profile is constant at a first distance; when the directional wheel assembly travels in a straight line, the roller is located outside the first profile; The diameter of the second contour gradually increases from the first distance to the second distance; when the directional wheel assembly rotates, the position of the roller gradually changes from the outside of the first contour to the outside of the second contour; When the rotation angle of the directional wheel assembly reaches a threshold value, the roller is located at the connection point of the first contour and the second contour, and the roller contacts the cam, thereby triggering the limiter; The diameter of the third contour is constant at the second distance.

3. The single-wheel steering mechanism according to claim 2, characterized in that: The maximum compression of the compression body is greater than the compression of the compression body when the roller is at a connection point of the first profile and the second profile.

4. The single-wheel steering mechanism according to claim 1, characterized in that: The synchronous pulley set includes a first pulley drivingly connected to the output end of the motor, a second pulley arranged on one radial side of the first pulley, and a synchronous belt sleeved on the first pulley and the second pulley.

5. The single-wheel steering mechanism according to claim 4, characterized in that: The single-wheel steering mechanism also includes a tensioning wheel, a base plate, a mounting plate and a limit pin; The tensioning wheel is arranged between the first pulley and the second pulley; The bottom plate is located on one side of the tension wheel in the axial direction, and the bottom plate is connected to the tension wheel; The mounting plate is arranged on a side of the bottom plate away from the tensioning wheel; a waist-shaped hole is provided on the side of the mounting plate facing the bottom plate, and the waist-shaped hole is arranged in the vertical direction; The limiting pin is movably arranged in the waist-shaped hole up and down, and one end of the limiting pin facing the bottom plate is connected to the bottom plate.

6. The single-wheel steering mechanism according to claim 5, characterized in that: The bevel gear set comprises a first bevel gear drivingly connected to the second pulley and a second bevel gear meshing with the first bevel gear; the axis of the second bevel gear is vertically arranged; The single-wheel steering mechanism further comprises a transmission shaft; the axis of the transmission shaft is perpendicular to the axis of the second bevel gear, and the second pulley and the first bevel gear are both disposed on the transmission shaft.

7. The single-wheel steering mechanism according to claim 6, characterized in that: The single-wheel steering mechanism also includes a fixing plate disposed above the directional wheel assembly; The motor, the synchronous pulley set and the bevel gear set are all arranged on the fixing plate.

8. The single-wheel steering mechanism according to claim 7, characterized in that: The single-wheel steering mechanism also includes a magnetic navigation module for detecting a magnetic field; The magnetic navigation module is arranged in front of the directional wheel assembly, and the magnetic navigation module is electrically connected to the control unit.

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