A steering mechanism and control method of a crawler harvester for hilly and mountainous areas

Abstract

The invention discloses a steering mechanism of a crawler harvester for hilly and mountainous areas and a control method thereof, comprising a steering frame, a steering reduction motor, a worm gear transmission mechanism, a crossbeam assembly, a left steering adjustment assembly, a right steering adjustment assembly and an electric control system; through the steering frame, the worm gear transmission mechanism, the crossbeam assembly, the left steering adjustment assembly and the right steering adjustment assembly, the wire-controlled steering control of the crawler harvester is realized, and at the same time, a steering mechanism control system consisting of a gyroscope sensor, an angle sensor, a rotation angle sensor, a steering controller, a steering reduction motor and a brushless motor is designed, a control strategy and a steering control method for wire-controlled steering are proposed, and high-precision, fast-response wire-controlled steering of the crawler harvester for hilly and mountainous areas is realized.

Description

Technical Field

[0001] The invention relates to the technical field of wire-controlled steering, and in particular to a steering mechanism of a crawler-type harvester for hilly and mountainous areas and a control method thereof. Background Art

[0002] The steer-by-wire system controls the steering system by sending the detected steering wheel angle information to the on-board electronic control unit ECU through sensors to achieve wheel steering. The steer-by-wire system solves the problems of high energy consumption, large road impact, and unadjustable steering sensitivity in traditional steering systems.

[0003] At present, the wire control steering technology has been applied to wheeled vehicles, but it is rarely used in tracked vehicles. Existing wire control steering technology is disclosed in the patent publication number "CN 113232722 B" as "a control method, control system and motor vehicle for a wire control steering system". This patent provides a control method and control system for a wire control steering system, which obtains the steering torque of the steering shaft, the steering wheel angle of the steering wheel and the driving speed, drives the steering wheel to turn according to the steering wheel angle, and the road sensing motor realizes the steering wheel return to the center according to the feedback torque. Although this technology can realize wire control steering, its application range is limited to wheeled vehicles and is not suitable for tracked vehicles. The hilly area has complex terrain, and the hilly and mountainous crawler harvester is an agricultural machinery suitable for use in hilly and mountainous areas. Therefore, how to apply the steering wheel wire control steering technology to the hilly and mountainous crawler harvester is a problem that needs to be solved. Summary of the invention

[0004] Aiming at the problem that the existing wire-controlled steering is not suitable for crawler vehicles, the present invention provides a steering mechanism of a crawler harvester for hilly and mountainous areas based on steering wheel wire-controlled steering and a control method thereof.

[0005] In order to achieve the above object, the technical solution provided by the present invention is as follows:

[0006] On the one hand, the present invention provides a steering mechanism for a crawler harvester for hilly and mountainous areas, comprising a steering frame, a steering reduction motor, a worm gear transmission mechanism, a crossbeam assembly, a left steering adjustment assembly, a right steering adjustment assembly and an electric control system;

[0007] The steering frame is vertically fixedly mounted on the drive axle housing; the steering reduction motor is mounted on the steering frame;

[0008] The worm gear transmission mechanism comprises a worm wheel and a worm, the worm is coaxially connected to the steering reduction motor, the worm wheel is hinged to the steering frame, and can rotate around the center point O of the worm wheel;

[0009] The crossbeam assembly comprises a crossbeam, a left guide sleeve and a right guide sleeve, wherein the left guide sleeve is coaxially sleeved on the left end of the crossbeam and can slide along the crossbeam in the CD section on the left side, and the right guide sleeve is coaxially sleeved on the right end of the crossbeam and can slide along the crossbeam in the EF section on the right side;

[0010] The left steering adjustment assembly and the right steering adjustment assembly have the same structure and are symmetrically hinged on the left guide sleeve and the right guide sleeve; the two steering adjustment assemblies each include a guide rail, a guide rod and a steering bracket, the guide rail is fixedly mounted on the steering frame on the same side, the guide rod is sleeved on the guide rail on the same side and hinged with the guide sleeve on the same side, and can slide back and forth along the guide rail on the same side; the steering bracket is hinged with the gearbox housing and connected to the brake pedal through a mechanical structure;

[0011] The electronic control system comprises a gyro sensor, a rotation angle sensor, an angle sensor, a steering reduction motor, a brushless motor and a steering controller. The gyro sensor is mounted on the vehicle body, the rotation angle sensor is mounted on the steering shaft of the steering wheel, the angle sensor is mounted on the crossbeam, the steering reduction motor is mounted on the steering frame, the brushless motor is mounted on the end of the steering shaft of the steering wheel, and the steering controller is fixedly mounted on the steering frame; the signal output ends of the gyro sensor, the rotation angle sensor and the angle sensor are all connected to the signal input end of the steering controller, and the signal output end of the steering controller is respectively connected to the steering reduction motor and the brushless motor to realize the control of the steering mechanism and the automatic return control of the steering wheel.

[0012] On the other hand, the present invention also provides a control method for the steering mechanism of the above-mentioned hilly and mountainous crawler harvester. The hilly and mountainous crawler harvester travels in a straight line. When the driver turns the steering wheel to the left or right, the angle sensor detects the steering wheel rotation angle α. At this time, the steering controller sends a command to the steering reduction motor. The steering reduction motor rotates to drive the worm gear to rotate counterclockwise or clockwise (the worm gear rotates counterclockwise when turning left, and the worm gear rotates clockwise when turning right). The worm gear drives the crossbeam to rotate counterclockwise or clockwise around point O (the crossbeam rotates counterclockwise when turning left, and the crossbeam rotates clockwise when turning right). At this time, the angle sensor detects the crossbeam swing angle β, and the steering controller analyzes and determines whether the crossbeam swing angle β is equal to the crossbeam swing angle limit value β max , if β=β max , the steering controller sends a command to the steering reduction motor to stop rotating. If β≠β max, the steering reduction motor continues to rotate, and at the same time, the sliding sleeve on one side slides in the opposite direction along the guide sleeve on the same side of the beam, pushing the guide rod on the same side to slide downward along the guide rail, and the guide rod pushes the steering bracket on the same side to rotate clockwise or counterclockwise (the steering bracket rotates clockwise when turning left, and the steering bracket rotates counterclockwise when turning right); the gyroscope sensor detects the vehicle heading angle δ and sends the information to the steering controller, the steering controller determines that the vehicle heading angle δ has reached the target orientation, the steering controller sends a command to the brushless motor, the brushless motor rotates, and drives the steering wheel to automatically return to the center position. When the steering wheel rotates at an angle α=0, the brushless motor stops rotating; the steering controller sends a command to the steering reduction motor, the steering reduction motor rotates in the opposite direction, the steering mechanism returns to its initial position, and the crawler harvester travels in a straight line along the target orientation.

[0013] Furthermore, when the vehicle is turning left or right, if the vehicle body heading angle δ has reached the target position, but the driver holds the steering wheel, causing the steering wheel to be unable to return automatically, the steering reduction motor maintains the existing steering angle, drives the steering mechanism to maintain its original position, and the vehicle keeps turning left or right. When the driver lets go, the brushless motor drives the steering wheel to automatically return to the original position, the steering mechanism returns to its initial position, and the crawler harvester keeps moving in a straight line along the target position.

[0014] Compared with the prior art, the technical effects of the present invention are:

[0015] The present invention proposes a steering mechanism for a crawler harvester for hilly and mountainous areas, which realizes wire-controlled steering control of the crawler harvester through a steering frame, a worm gear transmission mechanism, a crossbeam assembly, a left steering adjustment assembly and a right steering adjustment assembly. At the same time, a steering mechanism control system consisting of a gyroscope sensor, an angle sensor, a rotation angle sensor, a steering controller, a steering reduction motor and a brushless motor is designed, and a control strategy and a steering control method for wire-controlled steering are proposed, thereby realizing high-precision, fast-response wire-controlled steering of the crawler harvester for hilly and mountainous areas. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0017] Figure 1 A front view of the steering mechanism of a hilly and mountainous crawler harvester in a straight-line driving state provided by an embodiment of the present invention.

[0018] Figure 2 A front view of the steering mechanism of a crawler harvester for hilly and mountainous areas in a left-turn state provided by an embodiment of the present invention.

[0019] Figure 3 A front view of the steering mechanism of a crawler harvester for hilly and mountainous areas in a right-turn state provided by an embodiment of the present invention.

[0020] Figure 4 A flow chart of an electronic control system provided in an embodiment of the present invention.

[0021] Figure 5 This is a structural diagram of an electric control system provided in an embodiment of the present invention.

[0022] Description of reference numerals:

[0023] 1. Left steering bracket, 2. Left guide rod, 3. Left guide rail, 4. Left guide sleeve, 5. Crossbeam, 6. Worm gear, 7. Worm, 8. Angle sensor, 9. Steering reduction motor, 10. Steering rack, 11. Right guide sleeve, 12. Right guide rail, 13. Right guide rod, 14. Right steering bracket. DETAILED DESCRIPTION

[0024] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present invention.

[0025] like Figure 1-5 As shown, the present invention proposes a steering mechanism for a hilly and mountainous crawler harvester, which includes a steering frame 10, a steering reduction motor 9, a worm gear transmission mechanism, a crossbeam assembly, a left steering adjustment assembly, a right steering adjustment assembly and an electronic control system.

[0026] The steering frame 10 is vertically fixedly mounted on the drive axle housing;

[0027] The steering reduction motor 9 is installed on the steering frame 10;

[0028] The worm gear transmission mechanism includes a worm wheel 6 and a worm 7. The worm 7 is coaxially connected to the steering reduction motor 9. The worm wheel 6 is hinged to the steering frame 10 and can rotate around the center point O of the worm wheel. It is rigidly connected to the crossbeam 5.

[0029] The crossbeam assembly includes a crossbeam 5, a left guide sleeve 4 and a right guide sleeve 11. The crossbeam 5 is hingedly connected to the worm gear 6. The crossbeam 5 can rotate around point O. The left guide sleeve 4 is coaxially sleeved on the left end of the crossbeam 5 and can slide along the crossbeam 5 in the CD section on the left side. The right guide sleeve 11 is coaxially sleeved on the right end of the crossbeam 5 and can slide along the crossbeam 5 in the EF section on the right side.

[0030] The left steering adjustment assembly includes a left guide rod 2, a left guide rail 3 and a left steering bracket 1. The left guide rod 2 is hinged to the left guide sleeve 4. The left guide rail 3 is fixedly mounted on the steering frame 10. The left guide rod 2 is sleeved on the left guide rail 3 and can slide back and forth. The left steering bracket 1 is hinged to the gearbox housing and can rotate around point A. The circular hole X on the left steering bracket 1 is connected to the brake pedal through a mechanical structure.

[0031] The right steering adjustment assembly has the same structure as the left steering adjustment assembly. The right steering adjustment assembly includes a right guide rod 13, a right guide rail 12 and a right steering bracket 14. The right guide rod 13 is hinged to the right guide sleeve 11. The right guide rail 12 is fixedly mounted on the steering frame 10. The right guide rod 13 is sleeved on the right guide rail 12 and can slide back and forth. The right steering bracket 14 is hinged to the gearbox housing and can rotate around point B. The circular hole Y on the left steering bracket 14 is connected to the brake pedal through a mechanical structure.

[0032] The electronic control system includes a gyro sensor, a rotation angle sensor, an angle sensor, a steering reduction motor, a brushless motor and a steering controller. Among them, the gyro sensor is installed on the vehicle body, the rotation angle sensor is installed on the steering shaft of the steering wheel, the angle sensor is installed on the crossbeam 5, the steering reduction motor 9 is installed on the steering frame 10, the brushless motor is installed at the end of the steering shaft of the steering wheel, and the steering controller is fixedly installed on the steering frame 10. The signal output ends of the gyro sensor, the rotation angle sensor and the angle sensor are all connected to the signal input end of the steering controller, and the signal output end of the steering controller is respectively connected to the steering reduction motor and the brushless motor to realize the control of the steering mechanism and the automatic return control of the steering wheel.

[0033] An angle sensor is installed on the crossbeam 5 to detect the crossbeam swing angle information in real time, and then the motor is controlled to stop in time, thereby improving the control accuracy and quick response.

[0034] A steering angle sensor is installed on the steering wheel to improve control accuracy through feedback of the steering angle sensor signal.

[0035] The present invention also provides a control method for the above-mentioned steering mechanism, the control method includes two situations: the vehicle goes from straight driving to left turn and the vehicle goes from straight driving to right turn. Figure 3 and 4 As shown, the specific control process is as follows:

[0036] (i) When a vehicle turns left from a straight line, Figure 2 As shown:

[0037] The crawler harvester travels in a straight line. When the driver turns the steering wheel to the left, the steering angle sensor detects the steering wheel rotation angle α. At this time, the steering controller sends a command to the steering reduction motor 9. The steering reduction motor 9 rotates to drive the worm wheel 6 to rotate counterclockwise. The worm wheel 6 drives the cross beam 5 to rotate counterclockwise around point O. At this time, the angle sensor detects the cross beam swing angle β. The steering controller analyzes and determines whether the cross beam 5 swing angle β is equal to βmax (cross beam swing angle limit value). If β=βmax, the steering controller sends a command to the steering reduction motor 9 to stop rotating. If β≠βmax, the steering reduction motor 9 continues to rotate. At the same time, the left guide sleeve 4 slides to the right along the cross 5, pushing the left guide rod 2 to slide downward along the left guide rail 3. The left guide rod 2 pushes the left steering bracket 1 to rotate clockwise around point A. The gyroscope sensor sends the detected vehicle heading angle δ information to the steering controller. The steering controller determines that the vehicle heading angle δ has reached the target orientation. The steering controller sends a command to the brushless motor, the brushless motor rotates, and drives the steering wheel to automatically return to the center. When the steering wheel rotation angle α=0, the brushless motor stops rotating. The steering controller sends a command to the steering reduction motor 9, the steering reduction motor 9 rotates in the opposite direction, the steering mechanism returns to the initial position, and the crawler harvester travels in a straight line along the target direction.

[0038] When the vehicle is turning left, if the vehicle body heading angle δ has reached the target direction, but the driver holds the steering wheel, causing the steering wheel to be unable to return automatically, the steering reduction motor 9 maintains the existing steering angle, drives the steering mechanism to maintain its original position, and the vehicle keeps turning left. When the driver lets go, the brushless motor drives the steering wheel to automatically return to the original position, the steering mechanism returns to its initial position, and the crawler harvester keeps moving in a straight line along the target direction.

[0039] (ii) When a vehicle turns right from a straight line, Figure 3 As shown:

[0040] The crawler harvester travels in a straight line. When the driver turns the steering wheel to the right, the steering angle sensor detects the steering wheel rotation angle α. At this time, the steering controller sends a command to the steering reduction motor 9. The steering reduction motor 9 rotates to drive the worm gear 6 to rotate clockwise. The worm gear 6 drives the beam 5 to rotate clockwise around point O. At this time, the angle sensor detects the beam swing angle β. The steering controller analyzes and determines whether the beam swing angle β is equal to βmax (the beam swing angle limit value). If β=β max , the steering controller sends a command to the steering reduction motor 9 to stop rotating. If β≠β max, the steering reduction motor 9 continues to rotate, and at the same time the right guide sleeve 11 slides to the left along the cross beam 5, pushing the right guide rod 13 to slide downward along the right guide rail 12, and the right guide rod 13 pushes the right steering bracket 14 to rotate counterclockwise around point B. The gyroscope sensor detects the vehicle heading angle δ and sends it to the steering controller. The steering controller determines that the vehicle heading angle δ has reached the target orientation. The steering controller sends a command to the brushless motor, and the brushless motor rotates to drive the steering wheel to automatically return to the center. When the steering wheel rotates at an angle α=0, the brushless motor stops rotating. The steering controller sends a command to the steering reduction motor 9, and the steering reduction motor 9 rotates in the opposite direction. The steering mechanism returns to its initial position, and the crawler harvester drives in a straight line along the target orientation.

[0041] When the vehicle is turning right, if the vehicle body heading angle δ has reached the target direction, but the driver holds the steering wheel, causing the steering wheel to be unable to return automatically, the steering reduction motor 9 maintains the existing steering angle, drives the steering mechanism to maintain its original position, and the vehicle keeps turning left. When the driver lets go, the brushless motor drives the steering wheel to automatically return to the original position, the steering mechanism returns to its initial position, and the crawler harvester keeps moving in a straight line along the target direction.

[0042] The above description is only by way of illustration of certain exemplary embodiments of the present invention. It is undoubted that those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A steering mechanism for a crawler harvester for hilly and mountainous areas, characterized in that: It comprises a steering frame (10), a steering reduction motor (9), a worm gear transmission mechanism, a crossbeam assembly, a left steering adjustment assembly, a right steering adjustment assembly and an electronic control system; The steering frame (10) is vertically fixedly mounted on the drive axle housing; the steering reduction motor (9) is mounted on the steering frame (10); The worm gear transmission mechanism comprises a worm wheel (6) and a worm (7), wherein the worm (7) is coaxially connected to a steering reduction motor (9), and the worm wheel (6) is hinged to a steering frame (10) and can rotate around a center point O of the worm wheel; The crossbeam assembly comprises a crossbeam (5), a left guide sleeve (4) and a right guide sleeve (11); the left guide sleeve (4) is coaxially sleeved on the left end of the crossbeam (5) and can slide along the crossbeam (5) in the left CD section; the right guide sleeve (11) is coaxially sleeved on the right end of the crossbeam (5) and can slide along the crossbeam (5) in the right EF section; The left steering adjustment assembly and the right steering adjustment assembly have the same structure and are symmetrically hinged on the left guide sleeve (4) and the right guide sleeve (11); the two steering adjustment assemblies each include a guide rail, a guide rod and a steering bracket, the guide rail being fixedly mounted on the steering frame on the same side, the guide rod being sleeved on the guide rail on the same side and hinged with the guide sleeve on the same side and being able to reciprocate along the guide rail on the same side; the steering bracket being hinged with the gearbox housing and connected with the brake pedal via a mechanical structure; The electronic control system comprises a gyro sensor, a rotation angle sensor, an angle sensor (8), a steering reduction motor (9), a brushless motor and a steering controller. The gyro sensor is mounted on the vehicle body, the rotation angle sensor is mounted on the steering shaft of the steering wheel, the angle sensor (8) is mounted on the crossbeam (5), the steering reduction motor (9) is mounted on the steering frame (10), the brushless motor is mounted on the end of the steering shaft of the steering wheel, and the steering controller is fixedly mounted on the steering frame (10); the signal output ends of the gyro sensor, the rotation angle sensor and the angle sensor (8) are all connected to the signal input end of the steering controller, and the signal output end of the steering controller is respectively connected to the steering reduction motor and the brushless motor, so as to realize the control of the steering mechanism and the automatic return control of the steering wheel.

2. The control method of the steering mechanism of a crawler harvester for hilly and mountainous areas according to claim 1, characterized in that: The crawler harvester on a hilly mountainous area travels in a straight line. When the driver turns the steering wheel to the left or right, the steering angle sensor detects the steering wheel rotation angle α. At this time, the steering controller sends a command to the steering reduction motor (9). The steering reduction motor (9) rotates to drive the worm gear (6) to rotate counterclockwise or clockwise. The worm gear (6) drives the crossbeam (5) to rotate counterclockwise or clockwise around the point O. At this time, the angle sensor (8) detects the crossbeam (5) swing angle β. The steering controller analyzes and determines whether the crossbeam swing angle β is equal to the crossbeam (5) swing angle limit value β max , if β=β max , the steering controller sends a command to the steering reduction motor (9) to stop rotating. If β≠β max , the steering reduction motor (9) continues to rotate, and at the same time, the sliding sleeve on one side slides in the opposite direction along the guide sleeve on the same side of the cross beam (5), pushing the guide rod on the same side to slide downward along the guide rail, and the guide rod pushes the steering bracket on the same side to rotate clockwise or counterclockwise; the gyroscope sensor sends the information of the vehicle heading angle δ detected to the steering controller, and the steering controller determines that the vehicle heading angle δ has reached the target orientation, and the steering controller sends a command to the brushless motor, and the brushless motor rotates, driving the steering wheel to automatically return to the center position. When the steering wheel rotates at an angle α=0, the brushless motor stops rotating; the steering controller sends a command to the steering reduction motor (9), and the steering reduction motor (9) rotates in the opposite direction, the steering mechanism returns to the initial position, and the crawler harvester travels in a straight line along the target orientation.

3. The control method of the steering mechanism of a crawler harvester for hilly and mountainous areas according to claim 2, characterized in that: When the vehicle is turning left or right, if the vehicle body heading angle δ has reached the target orientation, but the driver holds the steering wheel so that the steering wheel cannot automatically return to its original position, the steering reduction motor (9) maintains the existing steering angle, drives the steering mechanism to maintain its original position, and the vehicle keeps turning left or right. When the driver lets go, the brushless motor drives the steering wheel to automatically return to the original position, the steering mechanism returns to its initial position, and the crawler harvester keeps moving in a straight line along the target orientation.

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