Rear wheel steering control device and loader

Abstract

The utility model provides a rear wheel steering control device and loader, this rear wheel steering control device includes chassis frame and two rear wheel steering mechanism, and each rear wheel steering mechanism includes two rear wheel components, synchronization component, drive assembly and controller, two rear wheel components interval arrangement, each rear wheel component includes rotary drive shaft, and two rotary drive shafts are along vertical direction and are connected with chassis frame rotationally and pass through chassis frame, synchronization component is connected with two rotary drive shafts respectively, drive assembly sets up on chassis frame, and is connected with synchronization component or with one rotary drive shaft, controller is connected with drive assembly electricity, and controller controls drive assembly movement when receiving the steering signal, and drive assembly drives synchronization component to drive two rotary drive shafts synchronous steering further, or drive assembly drives one rotary drive shaft to drive another rotary drive shaft synchronous steering through synchronization component. The rear wheel steering control device can reduce the wear and tear and replacement frequency of rear wheel.

Description

Technical Field

[0001] This utility model generally relates to the field of loader control technology, and more specifically, to a rear wheel steering control device and a loader. Background Technology

[0002] With the continuous and rapid development of the air logistics sector, loaders have become the main tool and important means of loading containerized cargo. The low failure rate and low maintenance rate of loaders are important means to ensure high efficiency in loading and unloading cargo.

[0003] In related technologies, during the use of loaders, the rear wheels are frequently damaged and prone to uneven wear, resulting in a high frequency of rear wheel replacement, increasing vehicle maintenance time and reducing work efficiency. Utility Model Content

[0004] This invention provides a rear wheel steering control device and loader, which reduces rear wheel wear and replacement frequency.

[0005] According to a first aspect of the present invention, a rear-wheel steering control device is provided, comprising: a chassis frame and two rear-wheel steering mechanisms arranged along a first direction, wherein each rear-wheel steering mechanism comprises: two rear-wheel assemblies arranged along a second direction; each rear-wheel assembly includes a rotary drive shaft, the two rotary drive shafts passing through the chassis frame in a vertical direction and rotatably connected to the chassis frame; a synchronization component, the synchronization component being connected to two of the rotary drive shafts in each group of rear-wheel assemblies; a drive component, the drive component being disposed on the chassis frame and connected to the synchronization component or to one of the rotary drive shafts; and a controller, the controller being electrically connected to the drive component; wherein, when the controller receives a steering signal, it controls the drive component to move, and the drive component further drives the synchronization component to synchronously steer the two rotary drive shafts, or the drive component drives one of the rotary drive shafts to synchronously steer the other rotary drive shaft through the synchronization component.

[0006] In one embodiment of this disclosure, the synchronization component includes a linkage mechanism, which includes: a pull rod; two connecting rods, one end of each of the two pull rods being rotatably connected to the pull rod, and the other end of each pull rod being fixedly connected to a corresponding rotary drive shaft.

[0007] In one embodiment of this disclosure, the drive assembly includes a telescopic mechanism, one end of which is rotatably connected to the pull rod, and the other end of which is rotatably connected to the chassis frame.

[0008] In one embodiment of this disclosure, the telescopic mechanism includes at least one of a hydraulic cylinder, an electric cylinder, and an electric push rod.

[0009] In one embodiment of this disclosure, the drive assembly includes a servo motor and a reducer. The reducer is fixed to the chassis frame and connected to the output shaft of the servo motor. The output shaft of the reducer is coaxially connected to the rotary drive shaft, or the output shaft of the reducer is connected to the rotary drive shaft via a transmission component.

[0010] In one embodiment of this disclosure, the synchronization component includes at least one of a timing belt, a gear set, and a linkage mechanism.

[0011] In one embodiment of this disclosure, the device further includes a rear wheel angle sensor, the rotation shaft of which is detachably connected to the corresponding rotary drive shaft.

[0012] In one embodiment of this disclosure, the controller is configured to: generate a steering signal in response to a steering angle value of the front wheel being within a preset angle range, the steering signal including a first rotation angle of the rotary drive shaft, to control the movement of the drive assembly based on the first rotation angle so that the two rotary drive shafts turn synchronously, the first rotation angle being the opposite of the steering angle value of the front wheel.

[0013] In one embodiment of this disclosure, the controller is configured to generate a reset signal in response to an updated steering angle value of the front wheel not being within a preset angle range. The reset signal includes a second rotation angle of the rotary drive shaft to control the movement of the drive assembly based on the second rotation angle, thereby resetting the two rear wheel assemblies.

[0014] According to a second aspect of the present invention, an embodiment of the present invention also provides a loader, including the aforementioned rear wheel steering control device.

[0015] One embodiment of this utility model has the following advantages or beneficial effects: The rear wheel steering control device and loader provided in this embodiment have two rear wheel assemblies connected to a synchronization assembly, a drive assembly connected to the synchronization assembly or to a rotary drive shaft, and a controller electrically connected to the drive assembly. The controller controls the movement of the drive assembly according to the steering signal. When the drive assembly is connected to the synchronization assembly, the synchronization assembly drives the two rotary drive shafts to rotate synchronously. When the drive assembly is connected to a rotary drive shaft, the rotation of that rotary drive wheel drives the other rotary drive shaft to rotate synchronously through the synchronization assembly. This enables the rear wheels to turn in any direction and move with driving force, avoiding lateral drag on the rear wheels, reducing abnormal wear on the rear wheels, and reducing the replacement frequency. Attached Figure Description

[0016] To better understand this invention, reference can be made to the embodiments shown in the following drawings. Components in the drawings are not necessarily to scale, and related elements may be omitted to emphasize and clearly illustrate the technical features of this invention. Furthermore, related elements or components may have different arrangements as known in the art. Additionally, in the drawings, the same reference numerals denote the same or similar components in various figures. The above and other features and advantages of this invention will become more apparent by describing exemplary embodiments of the invention in detail with reference to the drawings.

[0017] in: Figure 1 The figure shown is a perspective view of a rear wheel steering control device according to an embodiment of the present invention.

[0018] Figure 2 The image shown is a front view of a rear wheel steering control device according to an embodiment of the present invention.

[0019] Figure 3 The diagram shown is a top view of a rear wheel steering control device according to an embodiment of the present invention.

[0020] Figure 4 The image shown is a left view of a rear wheel steering control device according to an embodiment of the present invention.

[0021] Figure 5 The diagram shown is a control principle diagram of a rear wheel steering control device according to an embodiment of the present invention.

[0022] Figure 6 The diagram shown is a schematic diagram of the steering principle of a rear wheel steering control device according to an embodiment of the present invention.

[0023] The reference numerals in the attached figures are explained as follows: 100, Chassis frame; 200, Rear wheel assembly; 210, Rear wheel; 220, Wheel frame; 230, Rotary drive shaft; 240, Axle; 300, Drive assembly; 310, Support rod; 320, First pivot; 330, Power unit; 400, Synchronization assembly; 410, Tie rod; 420, Connecting rod; 430, Second pivot; 500, Rear wheel angle sensor; 510, Bracket; 600, Controller; 700, Front wheel; 710, Front wheel angle sensor. Detailed Implementation

[0024] The technical solutions of the exemplary embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. The exemplary embodiments described herein are for illustrative purposes only and are not intended to limit the scope of protection of this utility model. Therefore, it should be understood that various modifications and changes can be made to the exemplary embodiments without departing from the scope of protection of this utility model.

[0025] In the description of this utility model, unless otherwise expressly specified and limited, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance; the term "multiple" refers to two or more; and the term "and / or" includes any and all combinations of one or more of the associated listed items. In particular, references to "the / described" object or "an" object are also intended to indicate one of a possible plurality of such objects.

[0026] Unless otherwise specified or stated, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, an integral connection, an electrical connection, or a signal connection; "connection" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0027] Furthermore, in the description of this utility model, it should be understood that the directional terms such as "upper," "lower," "inner," and "outer" described in the exemplary embodiments of this utility model are used to describe the angles shown in the accompanying drawings and should not be construed as limiting the exemplary embodiments of this utility model. It should also be understood that, in the context, when referring to an element or feature connected to another element (one or more) "upper," "lower," "inner," or "outer," it can be directly connected to another element (one or more) "upper," "lower," "inner," or "outer," or indirectly connected to another element (one or more) "upper," "lower," "inner," or "outer" through an intermediate element.

[0028] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that the present invention will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore their detailed description will be omitted.

[0029] Loaders, as specialized equipment for loading and unloading cargo in airports, play a crucial role in air freight. Loaders can also be called container loaders. However, during the use of loaders, the rear wheel 210 (or rear support wheel) experiences abnormally severe wear and is prone to uneven wear, leading to a high frequency of damage, repair, and replacement of the rear wheel 210, increasing the loader's maintenance time and reducing its operating frequency.

[0030] Analysis of the replaced rear wheel 210 revealed that when the front wheel 700 (or front drive wheel) turns at a certain angle, the rear wheel 210 and the loader's instantaneous forward direction form a certain angle, indicating that the rear wheel 210 exhibits a dragging lateral velocity component. Due to the presence of this lateral velocity component, there are both lateral velocity and lateral displacement components in the direction perpendicular to the rear wheel 210's travel. Loaders typically weigh tens of tons, and each rubber-made rear wheel 210 carries a significant load; under the influence of the lateral components, the rear wheel 210 experiences abnormally significant wear.

[0031] Based on this, this embodiment provides a rear wheel steering control device, such as... Figures 1 to 5 As shown, the rear wheel steering control device includes a chassis frame 100 and two rear wheel steering mechanisms. The two rear wheel steering mechanisms are arranged at intervals along the first direction Y. Each rear wheel steering mechanism includes two rear wheel assemblies 200, a synchronization assembly 400, a drive assembly 300, and a controller 600. Two rear wheel assemblies 200 are arranged at intervals. Each rear wheel assembly 200 includes a rotary drive shaft 230. The two rotary drive shafts 230 pass through the chassis frame 100 in the vertical direction and are rotatably connected to the chassis frame 100. A synchronization assembly 400 is connected to the two rotary drive shafts 230 respectively. A drive assembly is set on the chassis frame 100 and is connected to the synchronization assembly 400 or to one rotary drive shaft 230. A controller 600 is electrically connected to the drive assembly 300. When the controller 600 receives a steering signal, it controls the drive assembly 300 to move. The drive assembly 300 then drives the synchronization assembly 400 to drive the two rotary drive shafts 230 to turn synchronously, or the drive assembly 300 drives one rotary drive shaft 230 to drive the other rotary drive shaft 230 to turn synchronously through the synchronization assembly 400. This achieves synchronous steering control of the rear wheels 210. Especially during the steering of the front wheels 700, the rear wheels 210 follow the synchronous steering, which can eliminate the lateral velocity component of the rear wheels 210 and avoid wear on the rear wheels 210.

[0032] It should be noted that, in the embodiments provided by this utility model, such as Figures 1-5 As shown, the vertical direction Z is perpendicular to the surface of the chassis frame 100; the first direction Y is parallel to the surface of the chassis frame 100 and intersects the vertical direction Z; the second direction X is parallel to the surface of the chassis frame 100 and intersects the vertical direction Z and the first direction Y. The second direction X can be understood as the direction of travel of the loader in this embodiment of the present invention. In the following embodiments, the vertical direction Z, the second direction X and the first direction Y will not be repeated. However, it should be understood that the above three directions do not have a specific limiting effect on the actual structural layout of the rear wheel steering control device. When the relative position of the rear wheel steering control device is changed, the above three directions will also be adaptively changed. This disclosure does not make specific limitations.

[0033] The chassis frame 100 can serve as the rear chassis frame 100 of the loader, used to support the containerized cargo carried by the loader.

[0034] The rear wheel steering mechanism is used to control the steering of the rear wheels 210. The two rear wheel steering mechanisms are respectively arranged on both sides of the rear of the chassis frame 100 along the first direction Y, that is, the chassis frame 100 is provided with two rear wheel assemblies 200 on the left and right sides respectively.

[0035] refer to Figure 1 In one embodiment, two rear wheel assemblies 200 may be arranged at intervals along a second direction X. Each rear wheel assembly 200 may include a rear wheel 210, a wheel frame 220, a rotary drive shaft 230, and a wheel axle 240. The wheel frame 220 is U-shaped, with the rear wheel 210 placed inside the wheel frame 220. The wheel axle 240 passes through the rear wheel 210 and is bolted to the wheel frames 220 on both sides of the rear wheel 210. The rear wheel 210 is rotatably connected to the wheel axle 240 via bearings. The bottom end of the rotary drive shaft 230 is fixedly connected to the end face of the wheel frame 220 away from the rear wheel 210, for example, by welding. The top end of the rotary drive shaft 230 passes through the chassis frame 100 and extends above the chassis frame 100. The rotary drive shaft 230 and the chassis frame 100 are connected by bearings, which are interference-fitted onto the chassis frame 100, thereby enabling the rotary drive shaft 230 to rotate relative to the chassis frame 100.

[0036] The synchronization component 400 is connected to two rotary drive shafts 230 respectively. The synchronization component 400 can ensure that the two rotary drive shafts 230 rotate synchronously, thereby synchronously adjusting the deflection direction of the rear wheel 210, avoiding the lateral velocity component and displacement component of the rear wheel 210 caused by the instantaneous rotation of the front wheel 700, and reducing the wear of the rear wheel 210.

[0037] In one embodiment, the drive component 300 can be connected to the synchronization component 400. When the controller 600 controls the drive component 300 to move, the drive component 300 drives the synchronization component 400 to drive the two rotary drive shafts 230 to rotate synchronously.

[0038] In another embodiment, the drive assembly 300 may also be connected to a rotary drive shaft 230. When the controller 600 controls the drive assembly 300 to move, the rotary drive shaft 230 drives the other rotary drive shaft 230 to rotate synchronously via the synchronization assembly 400. It should be noted that the rotary drive shaft 230 connected to the drive assembly 300 can be either of the two rotary drive shafts 230, and this disclosure does not make a specific limitation.

[0039] In one embodiment, the synchronization component 400 may include a timing belt, a gear set, a linkage mechanism, etc. The matching synchronization component 400 can be selected according to the drive component 300, which will be described in detail in subsequent embodiments.

[0040] The controller 600 controls the movement of the drive component 300, which may include the extension and retraction of the drive component 300 or the rotation of the drive component 300.

[0041] The controller 600 may specifically be a PLC control unit, used to receive steering signals and control the movement of the drive component 300 according to the steering signals.

[0042] The steering signal may include the rotation direction signal of the rear wheel 210 and the rotation angle of the rotary drive shaft 230. The rotation direction of the rear wheel 210 can be represented by + or -, and the rotation angle of the rotary drive shaft 230 can be represented by a numerical value. The + can be omitted. For example, +30° or 30° means controlling the rear wheel 210 to turn 30° to the right, and -30° means controlling the rear wheel 210 to turn 30° to the left.

[0043] It should be noted that the steering signal is an updated steering indication based on the current operating state of the rear wheel 210. When the loader is not turning, that is, when the direction of travel of the rear wheel 210 is consistent with the loader body, the rotation angle of the rotary drive shaft 230 is defined as 0°. Similarly, when the direction of travel of the front wheel 700 is consistent with the loader body, the steering angle of the front wheel 700 is defined as 0°.

[0044] The rear wheel steering control device provided in this embodiment has two rear wheel assemblies 200 connected to a synchronization assembly 400, a drive assembly 300 connected to the synchronization assembly 400 or to a rotary drive shaft 230, and a controller 600 electrically connected to the drive assembly 300. The controller 600 controls the movement of the drive assembly 300 according to the steering signal. When the drive assembly 300 is connected to the synchronization assembly 400, the synchronization assembly 400 drives the two rotary drive shafts 230 to rotate synchronously. When the drive assembly 300 is connected to one rotary drive shaft 230, the rotation of one rotary drive wheel drives the other rotary drive shaft 230 to rotate synchronously through the synchronization assembly 400. This enables the rear wheel 210 to turn in any direction and move with driving force, avoids lateral drag on the rear wheel 210, reduces abnormal wear on the rear wheel 210, and reduces the replacement frequency.

[0045] Continue to refer to Figures 1-5 In one embodiment, the synchronization component 400 includes a linkage mechanism, which includes a pull rod 410 and two connecting rods 420. One end of each pull rod 410 is rotatably connected to the pull rod 410, and the other end of each pull rod 410 is fixedly connected to a corresponding rotary drive shaft 230.

[0046] The ends of the connecting rods 420 can be rotatably connected to the pull rods 410 via the second rotating shafts 430 (e.g., pins). The other end of each connecting rod 420 can be fixedly connected to the corresponding rotary drive shaft 230 by welding. The height and tilt angle of the two connecting rods 420 relative to the chassis frame 100 are the same, so that the pull rods 410, the two connecting rods 420, and the two rotary drive shafts 230 form a four-bar 420 structure.

[0047] In one embodiment, the centerlines of the two rotary drive shafts 230 and the two second rotary shafts 430 are parallel to each other, and the distance between the centerlines of the two rotary drive shafts 230 is equal to the distance between the centerlines of the two second rotary shafts 430. The distance between the centerlines of the two rotary drive shafts 230 and the corresponding centerlines of the second rotary shafts 430 is equal, so that the projection of the centerlines of the two rotary drive shafts 230 and the two second rotary shafts 430 onto the plane of the chassis frame 100 is the four vertices of a parallelogram or rectangle. By driving the tie rod 410 to swing back and forth along the second direction X, the tie rod 410 can drive the connecting rod 420 to rotate around the corresponding rotary drive shaft 230 as the centerline, thereby realizing the synchronous steering of the two rear wheels 210, avoiding the lateral drag of the rear wheels 210, and reducing abnormal wear of the rear wheels 210.

[0048] Continue to refer to Figures 1-5 In one embodiment, the drive assembly 300 includes a telescopic mechanism, one end of which is rotatably connected to the pull rod 410, and the other end of which is rotatably connected to the chassis frame 100.

[0049] like Figure 1 As shown, a telescopic mechanism is disposed at one end of the connecting rod 420. One end of the telescopic mechanism can be rotatably connected to the end of the pull rod 410 via a first rotating shaft 320 (for example, the first rotating shaft 320 is a pin). The telescopic mechanism is disposed on the chassis frame 100 between the two rotary drive shafts 230, or the telescopic mechanism is disposed on the chassis frame 100. The telescopic mechanism and the two rotary drive shafts 230 are respectively located on both sides of the pull rod 410 along the first direction Y, and one end of the telescopic mechanism is rotatably connected to the middle of the pull rod 410.

[0050] The axis of the telescopic mechanism can be parallel to the axis of the pull rod 410, or, during the telescopic process, the axis of the telescopic mechanism and the axis of the pull rod 410 have an included angle β.

[0051] It should be noted that the location of the telescopic mechanism, the size of the included angle β, and the connection method with the linkage mechanism can be determined according to actual needs, and this disclosure does not impose specific limitations.

[0052] The telescopic mechanism can be mounted on the chassis frame 100 via a support rod 310. The bottom of the support rod 310 can be welded and fixed to the chassis frame 100, and the top of the support rod 310 is hinged to the other end of the telescopic mechanism.

[0053] In one embodiment, the telescopic mechanism includes at least one of a hydraulic cylinder, an electric cylinder, and an electric push rod. The device also includes a power unit 330, which is electrically connected to the controller 600. The power unit 330 can be hydraulic, providing high-pressure hydraulic power, and the corresponding telescopic mechanism can be a hydraulic cylinder; alternatively, the power unit 330 can be electric, providing electric power, and the corresponding telescopic mechanism can be an electric cylinder or an electric push rod, also known as an electric actuator.

[0054] In this embodiment, the telescopic mechanism drives the linkage mechanism, causing the telescopic movement of the telescopic mechanism to drive the tie rod 410 to translate linearly along the second direction X. The tie rod 410 drives the connecting rod 420 to swing, thereby causing the rotary drive shaft 230 to rotate and realize the synchronous steering of the rear wheel 210. This effectively avoids the lateral velocity component and displacement component of the rear wheel 210 during the turning process of the loader. The rear wheel 210 is in a rolling state, which greatly reduces the wear of the rear wheel 210 and achieves the purpose of reducing the wear of the rear wheel 210.

[0055] The rear wheel steering mechanism is designed with a parallelogram structure to ensure that the steering angles of the two rear wheel assemblies 200 on one side are consistent during the extension and retraction of the telescopic mechanism.

[0056] In another embodiment, the drive assembly 300 includes a servo motor and a reducer. The reducer is fixed to the chassis frame 100 and connected to the output shaft of the servo motor. The output shaft of the reducer is coaxially connected to a rotary drive shaft 230, or the output shaft of the reducer is connected to a rotary drive shaft 230 via a transmission component.

[0057] By connecting one of the two rotary drive shafts 230 coaxially to the output shaft of the reducer or through a transmission component, the rotary drive shaft 230 can be used as a power shaft to drive the other rotary drive shaft 230 to rotate via the synchronization component 400.

[0058] The aforementioned coaxial connection refers to the output shaft of the reducer being aligned with the axis of the rotary drive shaft 230.

[0059] The transmission component can be a gear set, which can include a driving gear and a driven gear that mesh with each other. For example, the output shaft of the reducer is provided with a driving gear, and the rotary drive shaft 230 is provided with a driven gear. The driving gear and the driven gear mesh, thereby controlling the rotation of the rotary drive shaft 230 through the reducer.

[0060] The transmission component can also be a transmission belt, which is sleeved on the output shaft of the reducer and a rotary drive shaft 230.

[0061] It should be noted that the transmission component can also be other components that can realize the transmission connection between the output shaft of the reducer and the rotary drive shaft 230. This disclosure does not specifically limit the specific structure of the transmission component.

[0062] In one embodiment, the synchronization component 400 includes at least one of a timing belt, a gear set, and a linkage mechanism.

[0063] When the synchronization component 400 is a timing belt, the timing belt can be fitted onto the two rotary drive shafts 230 to achieve synchronous rotation of the two rotary drive shafts 230.

[0064] When the synchronization component 400 is a gear set, gears are respectively installed on the two rotary drive shafts 230 and mesh with each other, which can also achieve synchronous rotation of the two rotary drive shafts 230.

[0065] When the synchronization component 400 is a linkage mechanism, the connecting mechanism can be the four-bar linkage mechanism in the aforementioned embodiment, or it can realize the synchronous steering of the two rotary drive shafts 230.

[0066] In this embodiment, a reducer drives one rotary drive shaft 230 to rotate, and a synchronization component 400 drives another rotary drive shaft 230 to rotate, thereby achieving synchronous steering of the rear wheels 210. This effectively avoids the lateral velocity and displacement components of the rear wheels 210 during the turning process of the loader. The rear wheels 210 are in a rolling state, which greatly reduces the wear on the rear wheels 210 and achieves the purpose of reducing the wear on the rear wheels 210.

[0067] Continue to refer to Figures 1-5 In one embodiment, the rear wheel steering control device further includes a rear wheel angle sensor 500, the rotation shaft of which is detachably connected to a corresponding rotary drive shaft 230.

[0068] The rear wheel angle sensor 500 and the rotary drive shaft 230 can be arranged opposite each other. The housing of the rear wheel angle sensor 500 is fixed to the chassis frame 100 by a bracket 510. The rotating shaft of the rear wheel angle sensor 500 is inserted into the rotary drive shaft 230. For example, the rotating shaft of the rear wheel angle sensor 500 has a D-shaped structure, which effectively prevents the rotating shaft of the rear wheel angle sensor 500 from rotating relative to the rotary drive shaft 230 and maintains coaxiality.

[0069] It should be noted that each rotary drive shaft 230 can be connected to the rear wheel angle sensor 500, or one rotary drive shaft 230 can be connected to the rear wheel angle sensor 500. This disclosure does not make any specific limitation.

[0070] In one embodiment, the controller 600 is configured to generate a steering signal in response to the steering angle value of the front wheel 700 being within a preset angle range. The steering signal includes a first rotation angle of the rotary drive shaft 230 to control the movement of the drive assembly 300 based on the first rotation angle so that the two rotary drive shafts 230 turn synchronously. The first rotation angle is the opposite of the steering angle value of the front wheel 700.

[0071] In this disclosure, the electrical control section includes a controller 600, a power unit 330, a drive assembly 300, a rear wheel angle sensor 500, and a front wheel angle sensor 710. The rear wheel angle sensor 500 can detect the rotation angle value of the rear wheel 210 in real time, and the front wheel angle sensor 710 can detect the steering angle value of the front wheel 700 in real time. The rear wheel angle sensor 500 and the front wheel angle sensor 710 are electrically connected to the controller 600, which can be a PLC control unit. The controller 600 can acquire the rotation angle value of the rear wheel 210 and the steering angle value of the front wheel 700 collected by the rear wheel angle sensor 500.

[0072] The endpoint values ​​of the aforementioned preset angle range can be virtual steering angle values. When the controller 600 detects that the steering angle value α of the front wheel 700 is greater than the virtual steering angle value delta, i.e., α > delta, the controller 600 determines that the driver has a steering intention and generates a steering signal. The controller 600 controls the power unit 330 to work, and the power unit 330 provides hydraulic power or electricity to the drive assembly 300. Under the command and control of the controller 600, the drive assembly 300 drives the synchronization assembly 400 to drive the two rotary drive shafts 230 to deflect by the first rotation angle.

[0073] The first rotation angle can be the opposite of the steering angle value of the front wheels at 70°, such as... Figure 6 As shown. It should be noted that only one rear wheel assembly 200 is shown for each rear wheel steering mechanism.

[0074] Previously, the front wheel 700 and the rear wheel 210 were always at the same deflection angle. When the front wheel 700 was moving forward or backward, the rear wheel 210 was also passively in a rolling state. The turning radius of the front wheel 700 was R1, and the turning radius of the rear wheel 210 was R2. Since the rear wheel 210 had no power, R1 > R2.

[0075] like Figure 6 As shown, when the first rotation angle of the rear wheel 210 is -α, by controlling the drive component 300 to make the wheel edge linear velocity of the front wheel 700 and the rear wheel 210 the same, the turning radius can be effectively reduced, enabling fast turning and flexible maneuvering in small spaces, and achieving a turning effect with a smaller radius.

[0076] In one embodiment, the controller 600 is configured to generate a reset signal in response to an updated steering angle value of the front wheel 700 not being within a preset angle range. The reset signal includes a second rotation angle of the rotating drive shaft 230 to control the movement of the drive assembly 300 based on the second rotation angle, thereby resetting the two rear wheel assemblies 200.

[0077] When the controller 600 detects that the steering angle value of the front wheel 700 changes from being within the preset angle range to being outside the preset angle range, it generates a reset signal. The reset signal is used to restore the rear wheel assembly 200 to the non-steering state of the vehicle.

[0078] When the loader body is turned to the desired forward or backward direction, the driver resets the steering wheel, the front wheel 700 returns to center, and the steering angle value α of the front wheel 700 is within the angle range of [-delta, delta]. The controller 600 determines that the steering is completed at this time, generates a reset signal, and the second rotation angle is the opposite of the first rotation angle, so that the actual deflection angle of the rear wheel 210 is 0.

[0079] In this embodiment, on the one hand, the steering angle of the front wheel 700 and the rear wheel 210 is measured in real time using sensor measurement technology, providing data basis for the controller 600 to control the steering angle; on the other hand, the controller 600 can detect the driver's intention in real time and control the drive component 300 to move, so that the rear wheel 210 follows the steering angle of the front wheel 700, avoiding lateral force drag on the rear wheel 210. Since the lateral velocity component and displacement component on the rear wheel 210 during the steering process are eliminated, the rear wheel 210 is in a rolling state during the turning process, thereby avoiding abnormal wear of the rear wheel 210.

[0080] This embodiment provides a loader, wherein the loader may be a container loader or other similar equipment. The loader includes the rear wheel steering control device described in the above embodiment. The loader provided in this embodiment, through the rear wheel steering control device, can control the rear wheels 210 to eliminate lateral drag, reduce abnormal wear of the rear wheels 210, and reduce the replacement frequency of the rear wheels 210.

[0081] It should be noted that the embodiments of this utility model are merely one example of the principles employed by the present utility model, as shown in the accompanying drawings and described herein. Those skilled in the art will clearly understand that the principles of this utility model are not limited to any details or components of the apparatus shown in the accompanying drawings or described in the specification.

[0082] It should be understood that this invention is not limited to the detailed structure and arrangement of the components described herein. This invention can have other embodiments and can be implemented and performed in various ways. The foregoing variations and modifications fall within the scope of this invention. It should be understood that the invention disclosed and defined herein extends to all alternative combinations of two or more individual features mentioned or apparent in the text and / or drawings. All these different combinations constitute multiple alternative aspects of this invention. The embodiments described in this specification illustrate the best known mode for implementing this invention and will enable those skilled in the art to utilize this invention.

[0083] Other embodiments of the present invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. The present invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein. The specification and exemplary embodiments are to be considered as exemplary only, and the true scope and spirit of the invention are indicated by the appended claims.

[0084] It should be understood that this utility model is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of protection of this utility model is limited only by the appended claims.

Claims

1. A rear-wheel steering control device, characterized in that, include: A chassis frame and two rear-wheel steering mechanisms, the two rear-wheel steering mechanisms being arranged along a first direction, wherein each of the rear-wheel steering mechanisms includes: Two rear wheel assemblies are arranged along a second direction; each rear wheel assembly includes a rotary drive shaft, and the two rotary drive shafts pass through the chassis frame in a vertical direction and are rotatably connected to the chassis frame. A synchronization component, which is connected to two of the rotary drive shafts in each rear wheel assembly; A drive assembly, which is mounted on the chassis frame and connected to the synchronization assembly or to one of the rotary drive shafts; Controller, which is electrically connected to the drive assembly; When the controller receives a steering signal, it controls the movement of the drive component, which in turn drives the synchronization component to drive the two rotary drive shafts to turn synchronously, or the drive component drives one of the rotary drive shafts to drive the other rotary drive shaft to turn synchronously through the synchronization component.

2. The rear wheel steering control device according to claim 1, characterized in that, The synchronization component includes a linkage mechanism, the linkage mechanism comprising: Pull rod; Two connecting rods, one end of each of the two connecting rods is rotatably connected to the connecting rod, and the other end of each connecting rod is fixedly connected to the corresponding rotary drive shaft.

3. The rear wheel steering control device according to claim 2, characterized in that, The drive assembly includes a telescopic mechanism, one end of which is rotatably connected to the pull rod, and the other end of which is rotatably connected to the chassis frame.

4. The rear wheel steering control device according to claim 3, characterized in that, The telescopic mechanism includes at least one of a hydraulic cylinder, an electric cylinder, and an electric push rod.

5. The rear wheel steering control device according to claim 1, characterized in that, The drive assembly includes a servo motor and a reducer. The reducer is fixed to the chassis frame and connected to the output shaft of the servo motor. The output shaft of the reducer is coaxially connected to the rotary drive shaft, or the output shaft of the reducer is connected to the rotary drive shaft through a transmission component.

6. The rear wheel steering control device according to claim 5, characterized in that, The synchronization component includes at least one of a timing belt, a gear set, and a linkage mechanism.

7. The rear wheel steering control device according to claim 1, characterized in that, The device also includes a rear wheel angle sensor, the rotation shaft of which is detachably connected to the corresponding rotary drive shaft.

8. The rear wheel steering control device according to claim 7, characterized in that, The controller is configured to generate a steering signal in response to the steering angle value of the front wheel being within a preset angle range. The steering signal includes a first rotation angle of the rotary drive shaft, and controls the movement of the drive assembly based on the first rotation angle to cause the two rotary drive shafts to turn synchronously. The first rotation angle is the opposite of the steering angle value of the front wheel.

9. The rear wheel steering control device according to claim 8, characterized in that, The controller is configured to generate a reset signal in response to an updated steering angle value of the front wheel not being within a preset angle range. The reset signal includes a second rotation angle of the rotary drive shaft to control the movement of the drive assembly based on the second rotation angle, thereby resetting the two rear wheel assemblies. The second rotation angle is the opposite of the first rotation angle.

10. A loader, characterized in that, Includes the rear wheel steering control device as described in any one of claims 1 to 9.

Images