CN116588183A - Composite steering articulated tractor and steering method thereof - Google Patents

Composite steering articulated tractor and steering method thereof Download PDF

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Publication number
CN116588183A
CN116588183A CN202310618265.7A CN202310618265A CN116588183A CN 116588183 A CN116588183 A CN 116588183A CN 202310618265 A CN202310618265 A CN 202310618265A CN 116588183 A CN116588183 A CN 116588183A
Authority
CN
China
Prior art keywords
steering
cylinder group
follow
front wheel
locking
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202310618265.7A
Other languages
Chinese (zh)
Inventor
肖名涛
陈震霖
李明
周文
周志
蒋艳铼
李靖
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Changsha Sanglaite Agricultural Mechanical Equipment Co Ltd
Original Assignee
Changsha Sanglaite Agricultural Mechanical Equipment Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Changsha Sanglaite Agricultural Mechanical Equipment Co Ltd filed Critical Changsha Sanglaite Agricultural Mechanical Equipment Co Ltd
Publication of CN116588183A publication Critical patent/CN116588183A/en
Pending legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D5/00—Power-assisted or power-driven steering
    • B62D5/06—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle
    • B62D5/062—Details, component parts
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
    • B60R16/00—Electric or fluid circuits specially adapted for vehicles and not otherwise provided for; Arrangement of elements of electric or fluid circuits specially adapted for vehicles and not otherwise provided for
    • B60R16/02—Electric or fluid circuits specially adapted for vehicles and not otherwise provided for; Arrangement of elements of electric or fluid circuits specially adapted for vehicles and not otherwise provided for electric constitutive elements
    • B60R16/023—Electric or fluid circuits specially adapted for vehicles and not otherwise provided for; Arrangement of elements of electric or fluid circuits specially adapted for vehicles and not otherwise provided for electric constitutive elements for transmission of signals between vehicle parts or subsystems
    • B60R16/0231—Circuits relating to the driving or the functioning of the vehicle
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D5/00—Power-assisted or power-driven steering
    • B62D5/06—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle
    • B62D5/08—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle characterised by type of steering valve used
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D6/00—Arrangements for automatically controlling steering depending on driving conditions sensed and responded to, e.g. control circuits
    • B62D6/001—Arrangements for automatically controlling steering depending on driving conditions sensed and responded to, e.g. control circuits the torque NOT being among the input parameters
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D7/00—Steering linkage; Stub axles or their mountings
    • B62D7/18—Steering knuckles; King pins
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D7/00—Steering linkage; Stub axles or their mountings
    • B62D7/20—Links, e.g. track rods
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/60—Other road transportation technologies with climate change mitigation effect
    • Y02T10/72—Electric energy management in electromobility

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Transportation (AREA)
  • Automation & Control Theory (AREA)
  • Guiding Agricultural Machines (AREA)

Abstract

The invention discloses a composite steering articulated tractor and a steering method thereof, wherein the composite steering articulated tractor comprises an electric control system, a front hub, a front axle, a front vehicle body, a rear axle and a steering mechanism, wherein the front hub is arranged on the front axle, the front axle is connected with the front vehicle body, the front vehicle body is connected with the rear vehicle body through a hinge point, and the steering mechanism is connected with the rear vehicle body, the front axle and the front hub; the steering mechanism comprises a steering oil cylinder, a straight locking steering oil cylinder group, a front wheel steering assembly, a front wheel steering pull rod, a steering rocker arm, a hinged steering pull rod, a follow-up steering rocker arm and a follow-up steering oil cylinder group which are connected in sequence; the front wheel steering assembly is connected with the front axle and the front wheel hub, the steering rocker arm is connected with the front vehicle body and the steering oil cylinder, the follow-up steering rocker arm and the follow-up steering oil cylinder group are connected with the rear vehicle body, and the straight locking steering oil cylinder group is connected with the front vehicle body and the rear vehicle body; the locking and unlocking of the lock straight steering cylinder group and the follow-up steering cylinder group are controlled through the electric control system, so that the locking or unlocking hinge point steering function is realized.

Description

Composite steering articulated tractor and steering method thereof
Technical Field
The invention relates to the technical field of tractors, in particular to a composite steering articulated tractor and a steering method thereof.
Background
The road in the hilly and mountainous areas of China is rugged, the ramp is numerous, and the road condition is complex. Meanwhile, the areas are mainly in the south of China, the south is full of rainwater, the method is suitable for planting crops such as rice and rape, and the rice fields are usually arranged into terraced fields or staggered hillock fields for water storage and leveling. The complex geographical topography and various paddy-upland rotation planting features of hilly and mountain areas are difficult to adapt to the conditions of the conventional tractor. The existing articulated tractor turns through a deflection hinge point, and the steering is equivalent to bending the vehicle body from the middle part of the vehicle body, has the characteristic of small steering radius, and is widely applied to road transportation in hilly and mountain areas. But only the articulated wheeled tractor with the steering hinge point is large in-situ turning occupation and poor in field operation applicability, so that the problem is solved, the existing part of articulated wheeled tractor is used for steering the front wheels while the steering hinge point is used for steering, the turning radius is greatly reduced, and the steering motor capability is improved.
Disclosure of Invention
The invention aims to solve the technical problem of overcoming the defects of the prior art and providing a tractor capable of steering the front wheels independently and compositely steering the hinge points and the front wheels and a steering method thereof.
In order to solve the technical problems, the invention adopts the following technical scheme:
the composite steering articulated tractor comprises an electric control system, a front hub, a front axle, a front vehicle body, a rear axle and a steering mechanism, wherein the front hub is arranged on the front axle, the front axle is connected with the front vehicle body, the front vehicle body is connected with the rear vehicle body through a hinge point, and the steering mechanism is connected with the rear vehicle body, the front axle and the front hub;
the steering mechanism comprises a steering oil cylinder, a straight locking steering oil cylinder group, a follow-up steering oil cylinder group, a front wheel steering assembly and a linkage assembly; the front wheel steering assembly is connected with the front axle and the front wheel hub, the linkage assembly is sequentially connected with the front wheel steering assembly, the front vehicle body, the rear vehicle body and the follow-up steering cylinder group, the steering cylinder is connected with the linkage assembly, the follow-up steering cylinder group is connected with the rear vehicle body, and two ends of the straight locking steering cylinder group are respectively connected with the front vehicle body and the rear vehicle body; the electric control system is used for controlling the locking and opening of the straight steering cylinder group and the follow-up steering cylinder group, when the steering wheel is rotated, the steering cylinder drives the linkage assembly to move forwards and backwards, and the linkage assembly drives the front wheel steering assembly to move to finish left or right rotation of the front wheel hub.
As a further improvement of the above technical scheme:
the electric control system comprises a mechanical control circuit and an electronic control circuit; the mechanical control circuit comprises a contactor, a normally closed switch and an electromagnet A; the electronic control circuit comprises a normally open switch, a resistor, a relay, a central control unit, an electromagnet B, an electromagnet C, an electromagnet D, a median sensor E and a median sensor F; and the mechanical control circuit and the electronic control circuit are electrically connected with the straight locking steering cylinder group and the follow-up steering cylinder group.
When the mechanical control circuit and the electronic control circuit are sequentially turned on within a certain time, the straight locking steering cylinder group is unlocked, and the follow-up steering cylinder group is locked.
The straight locking steering cylinder group comprises two-position two-way electromagnetic valves, an oil supplementing tank, an oil pipe and a hydraulic cylinder; the rod cavity and the rodless cavity of the hydraulic cylinder are respectively connected with one end of two-position two-way electromagnetic valves, and the other ends of the two-position two-way electromagnetic valves are respectively connected with the oil supplementing tank;
the electromagnet A is a control electromagnet of a two-position two-way electromagnetic valve connected with a rod cavity of a hydraulic cylinder in the locking steering cylinder group, the electromagnet B is a control electromagnet of a two-position two-way electromagnetic valve connected with a rodless cavity of a hydraulic cylinder in the locking steering cylinder group, and the median sensor E is a median sensor of the hydraulic cylinder of the locking steering cylinder group.
The follow-up steering cylinder group comprises two-position two-way electromagnetic valves, an oil supplementing tank, an oil pipe and a hydraulic cylinder; the rod cavity and the rodless cavity of the hydraulic cylinder are respectively connected with one end of two-position two-way electromagnetic valves, and the other ends of the two-position two-way electromagnetic valves are respectively connected with the oil supplementing tank;
the electromagnet C is a control electromagnet of a two-position two-way electromagnetic valve connected with a rod cavity of a hydraulic cylinder in the follow-up steering cylinder group, the electromagnet D is a control electromagnet of a two-position two-way electromagnetic valve connected with a rodless cavity of a hydraulic cylinder in the follow-up steering cylinder group, and the median sensor F is a median sensor of the hydraulic cylinder of the follow-up steering cylinder group.
The follow-up steering cylinder group comprises a two-position two-way electromagnetic valve, a tee joint, an oil supplementing box and a hydraulic cylinder, wherein a rod cavity and a rodless cavity of the hydraulic cylinder are respectively connected with the tee joint and the oil supplementing box, and the two-position two-way electromagnetic valve is positioned between the tee joint and the oil supplementing box.
The front wheel steering assembly comprises a right steering knuckle arm, a left steering knuckle arm and a steering tie rod, wherein the right steering knuckle arm is connected with the left steering knuckle arm through the steering tie rod, and the right steering knuckle arm is connected with the front wheel hub through steering knuckles respectively.
The linkage assembly comprises a front wheel steering pull rod, a steering rocker arm, a hinged steering pull rod and a follow-up steering rocker arm, wherein the steering rocker arm is connected with the front vehicle body, the follow-up steering rocker arm is connected with the rear vehicle body, two ends of the front wheel steering pull rod are respectively connected with the front wheel steering assembly and the steering rocker arm, two ends of the hinged steering pull rod are respectively connected with the steering rocker arm and the follow-up steering rocker arm, and the follow-up steering cylinder group is connected with the follow-up steering rocker arm.
When the steering wheel is rotated, the steering oil cylinder drives the front wheel steering pull rod or the steering rocker arm or the hinged steering pull rod or the follow-up steering rocker arm to move forwards or backwards, and then drives the front wheel steering assembly to move leftwards or rightwards.
The steering method of the composite steering articulated tractor comprises the steps of steering the independent front wheels and compositely steering the hinging points and the front wheels;
individual front wheel steering: locking a straight steering cylinder group, operating a rotating steering wheel to rotate left or right, retracting or extending the steering cylinder to drive a linkage assembly to rotate forward or backward, extending or retracting the follow-up steering cylinder group forward or backward, and driving the front wheel steering assembly to rotate left or right by the linkage assembly to realize left or right rotation of the front wheel hub;
hinge point and front wheel compound steering: the electric control system is used for unlocking the straight steering cylinder group, locking the follow-up steering cylinder group, retracting or extending the steering cylinder when the steering wheel is operated to turn left or right, driving the linkage assembly to turn forward or backward, and as the follow-up steering cylinder group is locked, the straight steering cylinder group extends forward or contracts backward, driving the front vehicle body to turn left or right around a hinge point, and simultaneously, the linkage assembly driving the front wheel steering assembly to move left or right, so that the front wheel hub is realized, and the front vehicle body is turned left or right.
The method comprises the steps of entering a hinge point and front wheel composite steering mode;
the switch of the contactor is opened, so that the electromagnet A is powered on, and simultaneously, an opening locking signal is input to the central control unit, at the moment, the rod cavity of the locking steering cylinder group and the oil way of the oil supplementing tank are opened, the rodless cavity of the locking steering cylinder group and the oil way of the oil supplementing tank are not opened, and the hydraulic cylinder of the locking steering cylinder group is continuously locked;
after the central control unit obtains the unlocking and locking information, the central control unit starts to detect the signals of the median sensor F and the starting confirmation signal, and simultaneously a driver opens a normally open switch within a specified time, the central control unit judges that the hinged steering is unlocked, at the moment, the electromagnet B, the electromagnet C and the electromagnet D are all electrified, the rodless cavity of the straight steering cylinder group and the oil way of the oil supplementing tank are also opened, at the moment, the hydraulic cylinders of the straight steering cylinder group can freely move, and the hydraulic cylinders of the follow-up steering cylinder group are locked at the middle position.
When the lock straight steering cylinder group is locked and the hinged steering pull rod is detached, the steering wheel is rotated, and the steering cylinder drives the front steering pull rod or the steering rocker arm or the follow-up steering rocker arm to move forwards or backwards, and drives the front steering assembly to move leftwards or rightwards, so that independent front wheel steering is realized;
when the lock straight steering cylinder group is unlocked, the hinged steering pull rod is installed, the follow-up steering cylinder group is locked or detached, and when the follow-up steering cylinder group connects the hinged steering pull rod with the rear vehicle body, the steering wheel is rotated, the steering cylinder front wheel steering pull rod or the steering rocker arm or the follow-up steering rocker arm moves forwards or backwards, and meanwhile, the lock straight steering cylinder group stretches forwards or contracts backwards to drive the front vehicle body to rotate left or right, so that the composite steering of the hinge point and the front wheels is realized.
Compared with the prior art, the invention has the advantages that:
according to the composite steering articulated tractor and the steering method thereof, the locking and opening of the straight steering cylinder group and the follow-up steering cylinder group are adopted, so that the tractor can realize the independent front wheel steering and the switching of the two steering modes of the composite steering of the hinge point and the front wheel, the independent front wheel steering mode can be applicable during normal road transportation, at the moment, the straight steering cylinder group is locked, the follow-up steering cylinder group is opened, the steering cylinder drives the linkage assembly to move forwards or backwards during the steering wheel rotation, the follow-up steering cylinder group is driven to stretch out or shrink, the front wheel steering assembly is driven to move leftwards or rightwards, the left or right steering of the front wheel hub is realized, the steering radius is large, and the safe driving can be ensured; when the small field is operated, the front wheel steering assembly is driven to move left or right around the hinging point by switching to a hinging point and front wheel composite steering mode, at the moment, the straight steering oil cylinder group is started, the follow-up steering oil cylinder group is locked, and when the steering wheel is rotated, the steering oil cylinder drives the linkage assembly to move forwards or backwards.
Drawings
Fig. 1 is a schematic diagram of the overall structure of the compound steering articulated tractor of the present invention.
Fig. 2 is a schematic structural diagram of the steering mechanism principle of the composite steering articulated tractor of the invention.
Fig. 3 is a schematic structural diagram of the steering cylinder working principle of the composite steering articulated tractor.
Fig. 4 is a schematic diagram of the principle and structure of the electric control system of the composite steering articulated tractor.
Fig. 5 is a schematic structural diagram of the single yaw front wheel steering principle of the compound steering articulated tractor of the present invention.
Fig. 6 is a schematic structural diagram of the compound steering principle of the compound steering articulated tractor of the present invention.
The reference numerals in the drawings denote:
1. a front hub; 2. a front axle; 3. a front body; 4. a hinge point; 5. a rear body; 6. a rear axle; 7. a steering mechanism; 8. a right knuckle arm; 9. a tie rod; 10. a left knuckle arm; 11. a knuckle; 12. a steering cylinder; 13. front wheel steering tie rod; 14. a steering rocker arm; 15. a hinged steering tie rod; 16. a follow-up steering cylinder group; 17. a follow-up steering rocker arm; 18. locking the steering cylinder group; 19. two-position two-way electromagnetic valve; 20. an oil supplementing tank; 21. an oil pipe; 22. a hydraulic cylinder; 23. a median sensor; 24. a power supply; 25. a normally open switch; 26. a resistor; 27. a relay; 28. a contactor; 29. a normally closed switch; 30. a central control unit; 31. an electric control system.
Detailed Description
The present invention will be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments are shown, for the purpose of illustrating the invention, but the scope of the invention is not limited to the specific embodiments shown.
Unless defined otherwise, all technical and scientific terms used hereinafter have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the scope of the present invention.
Unless otherwise specifically indicated, the various raw materials, reagents, instruments, equipment and the like used in the present invention are commercially available or may be prepared by existing methods.
The invention will be described in further detail with reference to the drawings and the specific examples.
Fig. 1 to 5 show an embodiment of the composite steering articulated tractor and the steering method thereof according to the present invention, which comprises an electric control system 31, a front wheel hub 1, a front axle 2, a front wheel body 3, a rear wheel body 5, a rear axle 6 and a steering mechanism 7, wherein the front wheel hub 1 is mounted on the front axle 2, the front axle 2 is connected with the front wheel body 3, the front wheel body 3 is connected with the rear wheel body 5 through a hinge point 4, and the steering mechanism 7 is connected with the rear wheel body 5, the front wheel body 3, the front axle 2 and the front wheel hub 1.
The steering mechanism 7 comprises a steering cylinder 12, a straight locking steering cylinder group 18, a follow-up steering cylinder group 16, a front wheel steering assembly and a linkage assembly, wherein the linkage assembly comprises a front wheel steering pull rod 13, a steering rocker arm 14, a hinged steering pull rod 15 and a follow-up steering rocker arm 17 which are sequentially connected; the front wheel steering assembly is connected with the front axle 2 and the front wheel hub 1, the steering rocker arm 14 is connected with the front vehicle body 3, the follow-up steering rocker arm 17 and the follow-up steering cylinder group 16 are connected with the rear vehicle body 5, the straight locking steering cylinder group 18 is connected with the front vehicle body 3 and the rear vehicle body 5, and when a user rotates a steering wheel, the steering cylinder 12 stretches and contracts to drive the front wheel steering pull rod 13 or the steering rocker arm 14 or the hinged steering pull rod 15 or the follow-up steering rocker arm 17 to rotate; the locking and unlocking of the locking steering cylinder group 18 and the follow-up steering cylinder group 16 are controlled through the electronic control system 31, so that the locking or unlocking hinge point steering function is realized, and the adaptation capacity of the hinge type tractor in hilly and mountainous areas is improved.
In this embodiment, two front hubs 1 are provided, and the front wheel steering assembly includes a right knuckle arm 8, a left knuckle arm 10, and a tie rod 9, the right knuckle arm 8, the left knuckle arm 10 being connected by the tie rod 9, the right knuckle arm 8, the left knuckle arm 10 being connected to the two front hubs 1 by a knuckle 11, respectively.
The steering method comprises the following steps: including individual front wheel steering and articulation point and front wheel compound steering.
When the independent front wheels steer, the locking steering cylinder group 18 is in a locking state, and specifically, the locking steering cylinder group 18 and the follow-up steering cylinder group 16 are respectively arranged at two sides of the rear vehicle body 5. Taking the left-turn steering cylinder 12 connected with the steering rocker arm 14 as an example, when the driver operates the steering wheel to turn left, the steering cylinder 12 retracts, as shown in fig. 5, in the retracting movement direction V 1 The steering arm 14 is driven to rotate forward, specifically, at this time, the steering arm 14 is driven to swing clockwise around the mounting point of the front vehicle body 3, and then the front wheel steering tie rod 13 is driven to rotate in the direction V 2 Direction movement, articulated steering tie 15 along V 3 Hydraulic pressure in directional movement, follow-up steering cylinder group 16Cylinder 22 is along V 4 The steering rod 13 drives the left knuckle arm 10 to rotate to realize left rotation of the left front hub 1, and the left knuckle arm 10 drives the steering tie rod 9 to rotate along V 5 The steering wheel moves in the direction, so that the right knuckle arm 8 is driven to rotate, the left rotation of the right front wheel is realized, and the left wheel and the right wheel synchronously rotate because the rod piece mechanism moves at the same time, so that the front wheel hub 1 deflects by an angle a.
Since the lock-up steering cylinder group 18 is in the locked-up state, although the articulated steering linkage 15 is in the V-direction 3 Direction movement, following the hydraulic cylinders 22 in the steering cylinder group 16 along V 4 The direction motion, but because the pneumatic cylinder 22 in follow-up steering cylinder group 16 can freely stretch out and draw back, follow-up steering rocker 17 freely rotates around its mounting point with back automobile body 5, can't drive articulated point 4 to turn to, and at this moment, the tractor can only realize alone front wheel steering, and the steering law of car at this moment are the same, are fit for being used for road transportation, and the security is good.
When turning right, the same principle as left turning, the turning is opposite, specifically: when the driver operates the steering wheel to turn right, the steering cylinder 12 is extended and the retracting movement direction is V 1 To drive the steering arm 14 to rotate backward, specifically, at this time, to drive the steering arm 14 to swing counterclockwise around the mounting point of the front vehicle body 3, and then to drive the front wheel steering tie rod 13 in the direction V 2 Is moved in the opposite direction of the articulated steering linkage 15 in V 3 Is moved in the opposite direction of V by the hydraulic cylinders 22 in the slave steering cylinder group 16 4 The front steering tie rod 13 drives the left steering knuckle arm 10 to rotate to realize the right-hand rotation of the left front hub 1, and the left steering knuckle arm 10 drives the steering tie rod 9 to rotate along V 5 The left and right wheels turn synchronously because the rod mechanism moves simultaneously, and the front wheel hub 1 deflects by an angle a.
When the tractor is in low-speed operation in the field, in order to obtain smaller turning radius and improve the maneuverability of the tractor, a composite steering mode of a hinge point and a front wheel can be started, at the moment, the straight locking steering cylinder group 18 is started through the electric control system 31, and the follow-up steering cylinder group 16 is locked to the leftTurning to an example, when the driver operates the steering wheel to turn left, the steering cylinder 12 is retracted from the neutral position, as shown in fig. 6, in a retraction movement direction V 1 At this time, the steering rocker 14 is driven to swing clockwise around the mounting point of the front vehicle body 3, and then the front wheel steering tie rod 13 is driven to rotate along V 2 Direction movement, articulated steering tie 15 along V 3 And (3) moving in the direction. Since the hydraulic cylinder 22 in the follow-up steering cylinder group 16 is stopped at the intermediate position and cannot move, the hydraulic cylinder 22 in the follow-up steering cylinder group 16, the rear vehicle body 5 and the follow-up steering rocker arm 17 form a stable triangle. The front steering pull rod 13 drives the left steering knuckle arm 10 to rotate so as to deflect the front wheels by an angle a, and the front steering pull rod 13 drives the left steering knuckle arm 10 and simultaneously drives the hinged steering pull rod 15 to rotate along V 3 The hinge point 4 deflects by beta degrees correspondingly in the direction, the front wheel deflects by gamma degrees relative to the central axis of the rear vehicle body 5, and gamma is equal to the sum of a and beta, wherein a and beta can be equal or unequal, and the optimal scheme is that beta is larger than a. The hinge point and the front wheel are combined to steer, so that the steering angle is improved, the turning radius of the tractor can be reduced, the capacity of small Tian Kuaishi is improved, and the steering device is particularly suitable for hilly and mountain areas.
When the tractor turns right in the mode of combining the hinge point and the front wheels, the driver operates the steering wheel to turn right, and the steering cylinder 12 extends from the middle position in the extending movement direction V 1 In the opposite direction of (2), the steering arm 14 is driven to swing counterclockwise around the mounting point of the front body 3, and then the front wheel steering rod 13 is driven to move along V 2 Is moved in the opposite direction of the articulated steering linkage 15 in V 3 Is moved in the opposite direction. Meanwhile, the hydraulic cylinder 22 in the follow-up steering cylinder group 16 can not move when being stopped at the middle position, and the hydraulic cylinder 22 in the follow-up steering cylinder group 16, the rear vehicle body 5 and the follow-up steering rocker arm 17 form a stable triangle. The front steering pull rod 13 drives the left steering knuckle arm 10 to rotate rightwards, so that the front wheel deflection angle is a degrees, and the front steering pull rod 13 drives the left steering knuckle arm 10 and simultaneously drives the hinged steering pull rod 15 to rotate along V 3 The hinge point 4 deflects by beta degrees correspondingly to realize right turn, and the front wheel deflects by gamma degrees relative to the central axis of the rear vehicle body 5 at the moment, wherein gamma is equal to the sum of a and beta, and a and beta can be equal or unequalThe optimal scheme is that beta is larger than a.
According to the composite steering articulated tractor and the steering method thereof, through locking and opening the straight steering cylinder group 18 and the follow-up steering cylinder group 16, the tractor can realize the switching of two steering modes of independent front wheel steering and the composite steering of a hinging point and a front wheel, and can be applicable to an independent front wheel steering mode during normal road transportation, at the moment, the straight steering cylinder group 18 is locked, the follow-up steering cylinder group 16 is opened, and when the steering wheel is rotated, the steering cylinder 12 drives the linkage assembly to move forwards or backwards, drives the follow-up steering cylinder group 16 to stretch out or shrink, drives the front wheel steering assembly to move leftwards or rightwards, realizes the left or right turning of the front wheel hub 1, has large steering radius and can ensure safe driving; when the small field is operated, the front wheel steering mode is switched to be a mode of combining the hinging point with the front wheel, at the moment, the straight steering cylinder group 18 is started, the follow-up steering cylinder group 16 is locked, when the steering wheel is rotated, the steering cylinder 12 drives the linkage assembly to move forwards or backwards, the straight steering cylinder group 18 is driven to stretch out or shrink due to the locking of the follow-up steering cylinder group 16, the front wheel steering assembly is driven to rotate left or right around the hinging point 4, and meanwhile, the front wheel steering assembly is driven to move left or right, so that the front wheel hub 1 and the hinging point 4 of the front wheel body 3 and the rear wheel body 5 are simultaneously steered, the steering radius is smaller, the occupied area of turning is small, the small-field steering device is suitable for the edge pasting operation or turning of the small field with complex boundaries, the applicability of hilly mountain areas is better, and the safety is good, and the operation is convenient.
When the steering cylinder 12 is connected with the front steering tie rod 13 or the hinged steering tie rod 15 or the follow-up steering rocker 17, the steering principle is similar to that when the steering cylinder 12 is connected with the steering rocker 14, except that when the steering wheel is turned, the steering cylinder 12 directly acts on the front steering tie rod 13 or the hinged steering tie rod 15 or the follow-up steering rocker 17, and then the front steering tie rod 13 or the hinged steering tie rod 15 or the follow-up steering rocker 17 drives the front connected structures to move back and forth, and finally drives the front steering assembly to realize steering.
In this embodiment, the compound steering articulated tractor includes an electric control system 31, and the electric control system 31 includes a power supply 24, a mechanical control circuit, and an electronic control circuit; the mechanical control circuit comprises a contactor 28, a normally closed switch 29 and an electromagnet A; the electronic control circuit comprises a normally open switch 25, a resistor 26, a relay 27, a central control unit 30, an electromagnet B, an electromagnet C, an electromagnet D, a median value sensor E and a median value sensor F; the locking steering cylinder group 18 and the follow-up steering cylinder group 16 are electrically connected through a mechanical control circuit and an electronic control circuit. When the composite steering mode is required to be started, the mechanical control circuit is required to be started at first, then the electronic control system is restarted within a certain time, the composite steering mode can be entered only when the mechanical control circuit and the electronic control circuit act simultaneously, and the system is prevented from being started by mistake through double insurance, so that the safety is improved.
The switching principle is as follows:
mechanical control circuit: when the switch of the contactor 28 is pressed, the electromagnet A is powered on, and simultaneously, an opening locking signal is input to the central control unit 30, the rod cavity of the straight steering cylinder group 18 and the oil circuit of the oil supplementing tank 20 are opened, and the hydraulic cylinder 22 continues to be locked because the rodless cavity of the straight steering cylinder group 18 and the oil circuit of the oil supplementing tank are not opened at the moment, so that the straight steering cylinder group 18 continues to play a locking role, and the tractor also mechanically works in a front wheel steering mode only.
An electronic control circuit: after the central control unit 30 obtains the unlocking locking signal, the central control unit 30 starts to detect the median value sensor F signal and the starting confirmation signal, when the median value sensor F signal is triggered and the driver presses the normally open switch 25 within a specified time, the central control unit 30 judges that the hinged steering is unlocked, at the moment, the electromagnet B, the electromagnet C and the electromagnet D are all electrified, the rodless cavity of the lock straight steering cylinder group 18 and the oil circuit of the oil supplementing box 20 are also opened, the hydraulic cylinder 22 of the lock straight steering cylinder group 18 can freely move, the hydraulic cylinder 22 of the follow-up steering cylinder group 16 is locked at the middle position, and the system enters a hinge point and front wheel compound steering mode. In order to prevent misoperation of the system, after the central control unit 30 detects that the starting confirmation signal of the electric control system 31 exceeds a preset value, the central control unit 30 does not control the electromagnet B, the electromagnet C and the electromagnet D to act even if the normally open switch 25 is pressed under the condition that the mechanical control circuit is opened, so that misoperation is prevented, and driving safety is improved.
When the mechanical control system is stopped, power is lost or the normally closed switch 29 is pressed down, the mechanical control system is in a straight locking state, so that the tractor can be ensured to work continuously after the composite steering device fails, and the safety is improved.
In one embodiment of the invention, the lock-up steering cylinder group 18 has the same structure as the follow-up steering cylinder group 16 and comprises a two-position two-way electromagnetic valve 19, an oil supplementing tank 20, an oil pipe 21 and a hydraulic cylinder 22; the rod cavity and the rodless cavity of the hydraulic cylinder 22 are respectively connected with one ends of two-position two-way electromagnetic valves 19, and the other ends of the two-position two-way electromagnetic valves 19 are respectively connected with an oil supplementing tank 20.
In another embodiment of the present invention, the following steering cylinder set 16 includes a two-position two-way electromagnetic valve 19, a tee joint, an oil compensating tank 20, and a hydraulic cylinder 22, where a rod cavity and a rodless cavity of the hydraulic cylinder 22 are respectively connected to the tee joint and the oil compensating tank 20, and the two-position two-way electromagnetic valve 19 is located between the tee joint and the oil compensating tank 20. The locking steering cylinder group 18 comprises a two-position two-way electromagnetic valve 19, an oil supplementing box 20, an oil pipe 21 and a hydraulic cylinder 22; the rod cavity and the rodless cavity of the hydraulic cylinder 22 are respectively connected with one ends of two-position two-way electromagnetic valves 19, and the other ends of the two-position two-way electromagnetic valves 19 are respectively connected with an oil supplementing tank 20.
The electromagnet A is a control electromagnet of a two-position two-way electromagnetic valve with a rod cavity of the locking steering cylinder group 18, the electromagnet B is a control electromagnet of a two-position two-way electromagnetic valve 19 without the rod cavity of the locking steering cylinder group 18, and the median sensor E is a median sensor 23 of a hydraulic cylinder 22 of the locking steering cylinder group 18; the electromagnet C is a control electromagnet of the two-position two-way electromagnetic valve 19 with a rod cavity of the follow-up steering cylinder group 16, the electromagnet D is a control electromagnet of the two-position two-way electromagnetic valve 19 without the rod cavity of the follow-up steering cylinder group 16, the median sensor F is a median sensor 23 of the hydraulic cylinder 22 of the follow-up steering cylinder group 16, when the composite steering is opened, the electronic control system can detect the state of the median sensor F, and the composite steering can be opened only when the median sensor F is triggered, so that the steering rules of front wheels and rear wheels keep a linear relationship. When the compound steering is closed, the electronic control system detects the state of the median value sensor E, and the compound steering can be closed only when the median value sensor E is triggered, and at the moment, the center line of the front vehicle body 3 and the center line of the rear vehicle body 5 pass through the hinge point 4 and are overlapped.
When the steering mode is switched to the hinging point and front wheel composite steering mode, the mechanical control circuit and the electronic control circuit control the electromagnet A, the electromagnet B, the electromagnet C and the electromagnet D of the two-position two-way electromagnetic valve 19 to be powered on, the hydraulic cylinder 22 of the follow-up steering cylinder group 16 is positioned at the middle position, the two-position two-way electromagnetic valve 19 of the follow-up steering cylinder group 16 locks the oil liquid with a rod cavity and a rodless cavity of the hydraulic cylinder 22, the hydraulic cylinder 22 cannot extend or retract, and the follow-up steering rocker 17 is fixed at a certain position. At this time, the two-position two-way electromagnetic valve 19 of the locking steering cylinder group 18 conducts the oil in the rod cavity and the rodless cavity of the hydraulic cylinder 22, the hydraulic oil can freely move in the rod cavity and the rodless cavity of the hydraulic cylinder 22, the oil pipe 21 and the oil supplementing box 20, the hydraulic cylinder 22 can correspondingly extend or retract, and the hinge point 4 can be driven to deflect.
Another embodiment of the invention: by eliminating the follow-up steering cylinder group 16 and the follow-up steering rocker 17, a simple steering scheme can be obtained, specifically, when the hydraulic cylinder 22 in the lock straight steering cylinder group 18 is locked at the middle position, the hinged steering pull rod 15 is detached, so that the steering rocker 14 is disconnected from the follow-up steering cylinder group 16, the follow-up steering cylinder group 16 can be locked or the follow-up steering cylinder group 16 and the follow-up steering rocker 17 can be directly detached, the steering cylinder 12 is connected with the steering rocker 14, and when a steering wheel is rotated, the steering cylinder 12 stretches and contracts to drive the steering rocker 14 to rotate to drive the front wheel steering pull rod 13 to move forwards or backwards to drive the front wheel steering assembly to move, and the steering of independent front wheels is realized.
When the hydraulic cylinder 22 in the straight steering cylinder group 18 is unlocked, the hinged steering pull rod 15 is installed, the follow-up steering cylinder group 16 is locked or the follow-up steering cylinder group 16 and the follow-up steering rocker arm 17 are directly detached, and the hinged steering pull rod 15 is connected with the rear vehicle body 5, the steering cylinder 12 is connected with the steering rocker arm 14, the steering wheel is rotated, the steering cylinder 12 stretches and contracts to drive the steering rocker arm 14 to rotate to drive the front wheel steering pull rod 13 to move forwards or backwards, and meanwhile, the hydraulic cylinder 22 in the straight steering cylinder group 18 stretches and contracts to drive the hinge point 4 to rotate to drive the front wheel steering assembly to move, so that the hinge point and the front wheel are combined to steer, the structure is simplified, and the same steering mode is achieved.
Another embodiment of the invention: the tie rod 9 is eliminated, the front steering tie rod 13 and the steering rocker 14 are correspondingly arranged on the right side, or a steering mechanism formed by the steering rocker 14 and the follow-up steering rocker 17 of the hinged steering tie rod 15 is arranged on the other side, or the steering mechanism formed by the steering rocker 14 and the follow-up steering rocker 17 of the hinged steering tie rod 15 is arranged on the same side with the locking steering cylinder group, and all the structural changes belong to the protection scope of the technology.

Claims (12)

1. The utility model provides a compound articulated tractor that turns to which characterized in that: the automobile steering device comprises an electric control system (31), a front wheel hub (1), a front axle (2), a front automobile body (3), a rear automobile body (5), a rear axle (6) and a steering mechanism (7), wherein the front wheel hub (1) is installed on the front axle (2), the front axle (2) is connected with the front automobile body (3), the front automobile body (3) is connected with the rear automobile body (5) through a hinging point (4), and the steering mechanism (7) is connected with the rear automobile body (5), the front automobile body (3), the front axle (2) and the front wheel hub (1);
the steering mechanism (7) comprises a steering oil cylinder (12), a straight locking steering oil cylinder group (18), a follow-up steering oil cylinder group (16), a front wheel steering assembly and a linkage assembly; the front wheel steering assembly is connected with the front axle (2) and the front wheel hub (1), the linkage assembly is sequentially connected with the front wheel steering assembly, the front vehicle body (3), the rear vehicle body (5) and the follow-up steering cylinder group (16), the steering cylinder (12) is connected with the linkage assembly, the follow-up steering cylinder group (16) is connected with the rear vehicle body (5), and two ends of the straight steering cylinder group (18) are respectively connected with the front vehicle body (3) and the rear vehicle body (5); the locking and opening of the straight locking steering cylinder group (18) and the follow-up steering cylinder group (16) are controlled through the electric control system (31), when the steering wheel is rotated, the steering cylinder (12) drives the linkage assembly to move back and forth, and the linkage assembly drives the front wheel steering assembly to move to finish left or right rotation of the front wheel hub (1).
2. A compound steering articulated tractor according to claim 1, characterized in that: the electric control system (31) comprises a mechanical control circuit and an electronic control circuit; the mechanical control circuit comprises a contactor (28), a normally closed switch (29) and an electromagnet A; the electronic control circuit comprises a normally open switch (25), a resistor (26), a relay (27), a central control unit (30), an electromagnet B, an electromagnet C, an electromagnet D, a median value sensor E and a median value sensor F; and the mechanical control circuit and the electronic control circuit are electrically connected with the straight locking steering cylinder group (18) and the follow-up steering cylinder group (16).
3. A compound steering articulated tractor according to claim 2, characterized in that: when the mechanical control circuit and the electronic control circuit are sequentially turned on within a certain time, the straight locking steering cylinder group (18) is unlocked, and the follow-up steering cylinder group (16) is locked.
4. A compound steering articulated tractor according to claim 2, characterized in that: the straight locking steering cylinder group (18) comprises two-position two-way electromagnetic valves (19), an oil supplementing box (20), an oil pipe (21) and a hydraulic cylinder (22); the rod cavity and the rodless cavity of the hydraulic cylinder (22) are respectively connected with one ends of two-position two-way electromagnetic valves (19), and the other ends of the two-position two-way electromagnetic valves (19) are respectively connected with the oil supplementing tank (20);
the electromagnet A is a control electromagnet of a two-position two-way electromagnetic valve connected with a rod cavity of a hydraulic cylinder (22) in the locking steering cylinder group (18), the electromagnet B is a control electromagnet of a two-position two-way electromagnetic valve (19) connected with a rodless cavity of the hydraulic cylinder (22) in the locking steering cylinder group (18), and the median sensor E is a median sensor of the hydraulic cylinder (22) of the locking steering cylinder group (18).
5. A compound steering articulated tractor according to claim 2, characterized in that: the follow-up steering cylinder group (16) comprises two-position two-way electromagnetic valves (19), an oil supplementing box (20), an oil pipe (21) and a hydraulic cylinder (22); the rod cavity and the rodless cavity of the hydraulic cylinder (22) are respectively connected with one ends of two-position two-way electromagnetic valves (19), and the other ends of the two-position two-way electromagnetic valves (19) are respectively connected with the oil supplementing tank (20);
the electromagnet C is a control electromagnet of a two-position two-way electromagnetic valve (19) connected with a rod cavity of a hydraulic cylinder (22) in the follow-up steering cylinder group (16), the electromagnet D is a control electromagnet of a two-position two-way electromagnetic valve (19) connected with a rodless cavity of the hydraulic cylinder (22) in the follow-up steering cylinder group (16), and the median sensor F is a median sensor (23) of the hydraulic cylinder (22) of the follow-up steering cylinder group (16).
6. A compound steering articulated tractor according to claim 1, characterized in that: the follow-up steering cylinder group (16) comprises a two-position two-way electromagnetic valve (19), a tee joint, an oil supplementing box (20) and a hydraulic cylinder (22), wherein a rod cavity and a rodless cavity of the hydraulic cylinder (22) are respectively connected with the tee joint and the oil supplementing box (20), and the two-position two-way electromagnetic valve (19) is positioned between the tee joint and the oil supplementing box (20).
7. A compound steering articulated tractor according to claim 1, characterized in that: the front wheel steering assembly comprises a right steering knuckle arm (31), a left steering knuckle arm (10) and a steering tie rod (9), wherein the right steering knuckle arm (31) and the left steering knuckle arm (10) are connected through the steering tie rod (9), and the right steering knuckle arm (31) and the left steering knuckle arm (10) are connected with the front wheel hub (1) through steering knuckles respectively.
8. A compound steering articulated tractor according to claim 1, characterized in that: the linkage assembly comprises a front wheel steering pull rod (13), a steering rocker arm (14), a hinged steering pull rod (15) and a follow-up steering rocker arm (17), wherein the steering rocker arm (14) is connected with the front vehicle body (3), the follow-up steering rocker arm (17) is connected with the rear vehicle body (5), the front wheel steering pull rod (13) is respectively connected with the front wheel steering assembly and the steering rocker arm (14), the two ends of the hinged steering pull rod (15) are respectively connected with the steering rocker arm (14) and the follow-up steering rocker arm (17), and the follow-up steering cylinder group (16) is connected with the follow-up steering rocker arm (17).
9. The steering method of a compound steering articulated tractor according to claim 8, wherein: when the steering wheel is rotated, the steering oil cylinder (12) drives the front wheel steering pull rod (13) or the steering rocker (14) or the hinged steering pull rod (15) or the follow-up steering rocker (17) to move forwards or backwards, and then drives the front wheel steering assembly to move leftwards or rightwards.
10. A steering method of a compound steering articulated tractor comprising a compound steering articulated tractor according to any of claims 1 to 9, characterized in that: the steering device comprises independent front wheel steering and composite steering of a hinge point and the front wheel;
individual front wheel steering: the locking and straightening steering cylinder group (18) is used for operating the steering wheel to turn left or right, the steering cylinder (12) is retracted or extended to drive the linkage assembly to turn forward or backward, the follow-up steering cylinder group (16) is extended forward or retracted backward, and the linkage assembly drives the front wheel steering assembly to turn left or right to realize left or right turning of the front wheel hub (1);
hinge point and front wheel compound steering: the electric control system is used for unlocking the lock straight steering cylinder group (18), locking the follow-up steering cylinder group (16), when the steering wheel is operated to rotate left or right, the steering cylinder (12) is retracted or extended to drive the linkage assembly to rotate forward or backward, and because the follow-up steering cylinder group (16) is locked, the lock straight steering cylinder group (18) is extended forward or contracted backward to drive the front vehicle body (3) to rotate left or right around the hinging point (4), and meanwhile, the linkage assembly drives the front wheel steering assembly to move left or right to realize left or right rotation of the front wheel hub (1) and the front vehicle body (3).
11. The steering method of a compound steering articulated tractor according to claim 10, wherein: the method comprises the steps of entering a hinge point and front wheel composite steering mode;
1) The switch of the contactor (28) is turned on to enable the electromagnet A to be electrified, and meanwhile, an opening locking signal is input to the central control unit (30), at the moment, the oil paths of the rod cavity of the locking steering cylinder group (18) and the oil supplementing tank (20) are opened, the oil paths of the rodless cavity of the locking steering cylinder group (18) and the oil supplementing tank (20) are not opened, and the hydraulic cylinders (22) of the locking steering cylinder group (18) are continuously locked;
2) After the central control unit (30) obtains the unlocking and locking information, the central control unit starts to detect the median value sensor F signal and the starting confirmation signal, and simultaneously a driver opens the normally open switch (25) within a specified time, the central control unit (30) judges that the hinged steering is unlocked, at the moment, the electromagnet B, the electromagnet C and the electromagnet D are all electrified, the rodless cavity of the straight steering cylinder group (18) and the oil circuit of the oil supplementing tank (20) are also opened, at the moment, the hydraulic cylinder (22) of the straight steering cylinder group (18) can freely move, and the hydraulic cylinder (22) of the follow-up steering cylinder group (16) is locked at the middle position.
12. The steering method of a compound steering articulated tractor according to claim 10, wherein:
when the locking steering cylinder group (18) is locked and the hinged steering pull rod (15) is detached, the steering wheel is rotated, and the steering cylinder (12) drives the front wheel steering pull rod (13) or the steering rocker arm (14) or the follow-up steering rocker arm (17) to move forwards or backwards, so that the front wheel steering assembly is driven to move leftwards or rightwards, and the steering of the independent front wheels is realized;
when the lock straight steering cylinder group (18) is unlocked, the hinged steering pull rod (15) is installed, the follow-up steering cylinder group (16) is locked or detached, when the follow-up steering cylinder group (16) connects the hinged steering pull rod (15) with the rear vehicle body, the steering wheel is rotated, the steering cylinder (12) front steering pull rod (13) or the steering rocker (14) or the follow-up steering rocker (17) moves forwards or backwards, and meanwhile, the lock straight steering cylinder group (18) stretches forwards or contracts backwards to drive the front vehicle body (3) to rotate left or right, so that the composite steering of the hinge point and the front wheels is realized.
CN202310618265.7A 2023-03-22 2023-05-29 Composite steering articulated tractor and steering method thereof Pending CN116588183A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN2023102869608 2023-03-22
CN202310286960 2023-03-22

Publications (1)

Publication Number Publication Date
CN116588183A true CN116588183A (en) 2023-08-15

Family

ID=87611427

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202310618265.7A Pending CN116588183A (en) 2023-03-22 2023-05-29 Composite steering articulated tractor and steering method thereof

Country Status (1)

Country Link
CN (1) CN116588183A (en)

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