All-electric loader and control method

Abstract

The invention provides an all-electric loader and a control method, and relates to the technical field of engineering machinery. The method comprises the steps that a first length parameter of a lifting electric cylinder and a second length parameter of a tipping bucket electric cylinder are obtained in the moving process of a movable arm; according to the first length parameter and the second length parameter, whether the movable arm interferes with the bucket in the moving process or not is judged; and if the movable arm interferes with the bucket in the moving process, the tipping bucket electric cylinder is controlled to act to drive the bucket to act, so that interference is relieved. According to the control method, a driver does not need to frequently control the tipping bucket electric cylinder to avoid interference, and driving can be simpler. Compared with hydraulic drive, multiple times of energy conversion are not needed, and therefore the energy utilization efficiency can be improved.

Description

Technical Field

[0001] This invention relates to the field of engineering machinery technology, and more specifically, to an all-electric loader and its control method. Background Technology

[0002] Loaders are multi-functional wheeled construction machines widely used in earthmoving projects, mines, construction sites, ports, and farmland. They are mainly used for loading, transporting, and unloading bulk materials. Based on their power source, loaders can be divided into two types: fuel-powered and purely electric. Among them, purely electric drive, with its advantages of environmental friendliness, energy saving, and high energy efficiency, is gradually becoming the mainstream direction for the future development of the industry.

[0003] Currently, the superstructure systems of pure electric loaders generally use an electric motor to drive a hydraulic pump, which in turn drives the cylinders to extend and retract to achieve movements such as the boom and bucket. To avoid motion interference, a pressure relief valve is typically installed in the hydraulic branch. However, because the power undergoes multiple conversions from electrical energy to mechanical energy to hydraulic energy, the overall energy utilization rate of the system remains relatively low, leaving room for further optimization. Summary of the Invention

[0004] The present invention aims to provide a fully electric loader and its control method. By employing automatic anti-interference control, it eliminates the need for frequent driver intervention in controlling the dump engine, thus simplifying operation. Compared to hydraulic drives, it eliminates the need for multiple energy conversions, thereby improving energy efficiency.

[0005] The embodiments of the present invention can be implemented as follows: Firstly, this application discloses a control method for an all-electric loader, applied to an all-electric loader, which includes: The vehicle frame has an electric drive system; The bucket is equipped with a bucket retraction limit block and a bucket tipping limit block; The boom is hinged at one end to the vehicle frame and at the other end to the bucket; A lifting electric cylinder, one end of which is hinged to the boom and the other end of which is hinged to the vehicle frame; The rocker arm is hinged to the movable arm in the middle. The connecting rod is hinged at one end to the bucket and at the other end to the front end of the rocker arm; The tipping electric cylinder is hinged at one end to the vehicle frame and at the other end to the rear end of the rocker arm. When the tipping electric cylinder drives the bucket to rotate to the bucket retraction limit state, the bucket retraction limit block abuts against the boom. When the tipping electric cylinder drives the bucket to rotate to the tipping limit state, the tipping limit block abuts against the boom; The method includes: During the boom movement, the first length parameter of the lifting electric cylinder and the second length parameter of the tipping electric cylinder are obtained; Based on the first length parameter and the second length parameter, it is determined whether the boom will interfere with the bucket during its movement; If the boom interferes with the bucket during its movement, the tipping electric cylinder is controlled to move the bucket to eliminate the interference.

[0006] In an optional implementation, the step of determining whether the boom will interfere with the bucket during movement based on the first length parameter and the second length parameter includes: During the extension process of the lifting electric cylinder, it is determined whether the first length parameter is greater than or equal to a first preset threshold. If the first length parameter is greater than or equal to the first preset threshold, then the first target length of the tipping electric cylinder is calculated based on the first length parameter when the boom and the tipping limit block interfere with each other. Determine whether the second length parameter is less than the first target length; If the second length parameter is less than the first target length, it is determined that the boom will interfere with the tipping bucket limit block during the lifting process; The step of controlling the tilting electric cylinder to move the bucket to eliminate interference includes: If no driver control command is received for the corresponding tipping electric cylinder, the tipping electric cylinder is automatically controlled to extend to the first target length.

[0007] In an optional implementation, the first preset threshold is the difference between the length of the tilting electric cylinder at its minimum value and the length of the lifting electric cylinder corresponding to the tilting limit block and the boom when the lifting electric cylinder extends to the point where the tilting limit block and the boom are in contact and limited, and the first safety threshold.

[0008] In an optional implementation, the step of calculating the first target length of the tilting electric cylinder when the boom and the tilting limit block interfere with each other based on the first length parameter includes: ∠AOD=acos((OA²+OD²-AD²) / (2*OA*OD)); ∠BOC = ∠AOD - ∠AOB + ∠COD; b= ; M1 = b + Y1; Wherein, O is the hinge center between the boom and the frame, A is the hinge center between the lifting electric cylinder and the frame, B is the hinge center between the dump electric cylinder and the frame, C is the hinge center between the dump electric cylinder and the rocker arm, D is the hinge center between the lifting electric cylinder and the boom, BC is the distance between the hinge centers of the dump electric cylinder and the frame and the hinge centers of the dump electric cylinder and the rocker arm, AD is the first length parameter, Y1 is the second safety threshold, and M1 is the first target length.

[0009] In an optional implementation, the step of determining whether the boom will interfere with the bucket during movement based on the first length parameter and the second length parameter further includes: During the shortening process of the lifting electric cylinder, it is determined whether the first length parameter is less than or equal to the second preset threshold. If the first length parameter is less than or equal to the second preset threshold, then the second target length of the tipping electric cylinder is calculated based on the first length parameter when the boom and the bucket limiting block interfere with each other. Determine whether the second length parameter is greater than the second target length; If the second length parameter is greater than the second target length, it is determined that the boom will interfere with the bucket limiting block during the descent process. The step of automatically controlling the tipping electric cylinder to drive the bucket movement to eliminate interference includes: If no driver control command is received for the corresponding tipping electric cylinder, the tipping electric cylinder is automatically shortened to release the interference.

[0010] In an optional implementation, the second preset threshold is the sum of the length of the tipping electric cylinder at its maximum value and the length of the lifting electric cylinder corresponding to the bucket closing limit block when it is shortened to the point where the bucket closing limit block abuts against the boom, and the third safety threshold.

[0011] In an optional implementation, the step of calculating the second target length of the tipping electric cylinder based on the first length parameter when the boom and the bucket-collecting limit block interfere with each other includes: ∠AOD=acos((OA²+OD²-AD²) / (2*OA*OD)); ∠BOC = ∠AOD - ∠AOB + ∠COD; d=

[0012] M2 = d - Y2; Wherein, O is the hinge center between the boom and the frame, A is the hinge center between the lifting electric cylinder and the frame, B is the hinge center between the dump electric cylinder and the frame, C is the hinge center between the dump electric cylinder and the rocker arm, D is the hinge center between the lifting electric cylinder and the boom, BC is the distance between the hinge centers of the dump electric cylinder and the frame and the hinge center of the dump electric cylinder and the rocker arm, AD is the distance between the hinge centers of the lifting electric cylinder and the frame and the lifting electric cylinder and the boom; the length of CD and ∠COD are constants; Y2 is the fourth safety threshold, and M2 is the second target length.

[0013] In an optional implementation, the step of automatically controlling the tipping electric cylinder to shorten to eliminate interference includes: If no driver control command corresponding to the tipping electric cylinder is received, the tipping electric cylinder is automatically controlled to shorten to the second target length.

[0014] In an optional implementation, the step of automatically controlling the tipping electric cylinder to shorten to eliminate interference includes: If both the driver's control command corresponding to the tipping electric cylinder and the shortening command corresponding to the lifting electric cylinder are received simultaneously, the brake of the tipping electric cylinder is unlocked, and a holding torque is applied to the tipping electric cylinder so that the tipping electric cylinder shortens when the torque it can withstand is greater than the holding torque.

[0015] Secondly, this application also provides an all-electric loader, including a controller, which is electrically connected to the tipping electric cylinder and the lifting electric cylinder, and the controller is capable of controlling the tipping electric cylinder according to the all-electric loader control method described in any of the above optional embodiments.

[0016] The beneficial effects of the all-electric loader control method and the all-electric loader provided in this invention include: This application acquires a first length parameter of the lifting electric cylinder and a second length parameter of the tipping electric cylinder during boom movement. Based on these parameters, it determines whether the boom will interfere with the bucket during movement. If interference is expected, the tipping electric cylinder is controlled to move the bucket and resolve the interference. This eliminates the need for frequent operator control of the tipping electric cylinder, simplifying operation. Compared to hydraulic drives, it eliminates the need for multiple energy conversions, thus improving energy efficiency. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a structural schematic diagram of the all-electric loader provided in this embodiment; Figure 2 This is a schematic diagram of the all-electric loader provided in this embodiment in its first state. Figure 3 This is a structural schematic diagram of the all-electric loader provided in this embodiment in the second state; Figure 4 This is a structural diagram of the all-electric loader in the third state provided in this embodiment; Figure 5 This is a structural diagram of the all-electric loader in the fourth state provided in this embodiment; Figure 6 This is a control flowchart of the all-electric loader control method provided in this embodiment; Figure 7 This is a specific control flowchart of the all-electric loader control method provided in this embodiment; Figure 8 This is another specific control flowchart of the all-electric loader control method provided in this embodiment; Figure 9 This is another control flowchart of the all-electric loader control method provided in this embodiment.

[0019] Icons: 100 - All-electric loader; 110 - Chassis; 120 - Bucket; 130 - Boom; 140 - Lifting electric cylinder; 150 - Rocker arm; 160 - Linkage; 170 - Dumping electric cylinder; 121 - Bucket closing limit block; 122 - Dumping limit block; O - Boom and chassis hinge center; A - Lifting electric cylinder and chassis hinge center; B - Dumping electric cylinder and chassis hinge center; C - Dumping electric cylinder and rocker arm hinge center; D - Lifting electric cylinder and boom hinge center. Detailed Implementation

[0020] Currently, the superstructure systems of pure electric loaders generally use an electric motor to drive a hydraulic pump, which in turn drives the cylinders to extend and retract to achieve movements such as the boom and bucket. To avoid motion interference, a pressure relief valve is typically installed in the hydraulic branch. However, because the power undergoes multiple conversions from electrical energy to mechanical energy to hydraulic energy, the overall energy utilization rate of the system remains relatively low, leaving room for further optimization.

[0021] To address the aforementioned problems, this invention provides an all-electric loader and its control method, which can improve energy utilization efficiency and mitigate motion interference issues.

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0023] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0024] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0025] In the description of this invention, it should be noted that if terms such as "upper," "lower," "inner," or "outer" are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed, they are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0026] Furthermore, the terms "first" and "second" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0027] It should be noted that, where there is no conflict, the features in the embodiments of the present invention can be combined with each other.

[0028] The following detailed description of the overall structure, working principle, and technical effects of the all-electric loader and its control method provided by the present invention, through embodiments and in conjunction with the accompanying drawings, is a practical example.

[0029] Please refer to Figure 1 This embodiment provides a fully electric loader 100, which can perform operations such as shoveling, transporting and unloading of bulk materials.

[0030] Please refer to Figure 1In this embodiment, the all-electric loader 100 includes a frame 110, a bucket 120, a boom 130, a lifting electric cylinder 140, a rocker arm 150, a connecting rod 160, a tipping electric cylinder 170, and a controller. The frame 110 has an electric travel system. The bucket 120 is provided with a bucket retraction limit block 121 and a tipping limit block 122. One end of the boom 130 is hinged to the frame 110, and the other end is hinged to the bucket 120. One end of the lifting electric cylinder 140 is hinged to the boom 130, and the other end is hinged to the frame 110. The middle part of the rocker arm 150 is hinged to the boom 130. One end of the connecting rod 160 is hinged to the bucket 120, and the other end is hinged to the front end of the rocker arm 150. One end of the tipping electric cylinder 170 is hinged to the frame 110, and the other end is hinged to the rear end of the rocker arm 150. When the bucket electric cylinder 170 drives the bucket 120 to rotate to the bucket retraction limit state, the bucket retraction limit block 121 abuts against the boom 130. When the bucket electric cylinder 170 drives the bucket 120 to rotate to the bucket tilting limit state, the bucket tilting limit block 122 abuts against the boom 130. The controller (not shown) is electrically connected to the lifting electric cylinder 140, the bucket electric cylinder 170, and the driver's operating mechanism (not shown). The operating mechanism is used by the driver to input corresponding driver operation commands to control the extension and retraction of the lifting electric cylinder 140 and the bucket electric cylinder 170 through the controller. The controller can also perform anti-interference detection and control according to the following all-electric loader control method, so as to control the operation of the bucket electric cylinder 170 when interference may occur during the movement of the boom 130, thereby avoiding interference problems and eliminating the need for the driver to frequently control the bucket electric cylinder 170, making driving simpler.

[0031] In this embodiment, the boom 130 is driven to move by the lifting electric cylinder 140, and the bucket is driven to move by the tipping electric cylinder 170. This eliminates the need to convert electrical energy into hydraulic energy; the lifting electric cylinder 140 and tipping electric cylinder 170 directly convert electrical energy into kinetic energy to drive the superstructure system, thereby improving energy efficiency. Furthermore, the controller can automatically control the tipping electric cylinder 170 to extend or retract to avoid interference when the bucket 120 is in its retracted or tipping limit state and the lifting electric cylinder 140 is in motion.

[0032] It should be noted that both the lifting electric cylinder 140 and the tipping electric cylinder 170 include a motor, gearbox, high-precision ball screw pair, and brake. Together, they convert the rotational motion of the motor into linear motion. The brake is located at the rear end of the motor and is a normally closed electromagnetic control. When the electric cylinder stops moving, the brake is locked; when the electric cylinder receives a movement command, it is energized to release the brake and allow the electric cylinder to extend or retract.

[0033] The all-electric loader 100 in this embodiment eliminates the hydraulic system, using electric cylinders instead of hydraulic cylinders as the actuators. The overall efficiency of the electric cylinder system can reach 80%, which reduces energy consumption and extends the operating time on a single charge for purely electric equipment. Furthermore, electric cylinders offer high control precision; when using servo motors, sub-millimeter level control accuracy can be achieved, enabling coordinated control of multiple actions. When the electric cylinder stops moving, its position can be briefly maintained by electromotive force.

[0034] Due to the structural characteristics of the six-bar linkage that drives the bucket 120, if the boom 130 continues to rise when the bucket 120 is in its tipping limit state, the tipping limit block 122 will cause the tipping electric cylinder 170 to tend to be stretched. If the boom 130 descends when the bucket 120 is in its retracted limit state, the retracted limit block 121 will cause the tipping electric cylinder 170 to tend to be compressed. In both cases, interference will occur, affecting the execution of the boom 130's movement and potentially damaging the tipping electric cylinder 170.

[0035] Please refer to Figure 2 and Figure 3 In position one, with the bucket 120 and boom 130 in state one, the tipping electric cylinder 170 retracts to its shortest length, and the tipping limit block 122 just collides with and limits the boom 130. Since the rotation center of the boom 130 is not concentric with the rotation center of the tipping electric cylinder 170, when the lifting electric cylinder 140 in state one shortens, it causes the boom 130 to descend, and the tipping limit block 122 tends to separate from the boom 130. The bucket 120 rotates clockwise relative to the boom 130, and the mechanism can move freely. When the lifting electric cylinder 140 in state one extends, it causes the boom 130 to rise, and the tipping limit block 122 of the bucket 120 tends to approach the boom 130. The bucket 120 rotates counterclockwise relative to the boom 130. Since the tipping limit block 122 has collided with the boom 130, the boom 130, rocker arm 150, connecting rod 160, and bucket 120 are locked together, restricting the movement of the mechanism. To advance the mechanism from state one to state two, the tipping electric cylinder 170 must be extended appropriately.

[0036] Please refer to Figure 4 and Figure 5In position three, with the bucket 120 and boom 130 in position three, the tipping electric cylinder 170 extends to its maximum length, and the bucket retraction limit block 121 just collides and limits the boom 130. Since the rotation center of the boom 130 is not concentric with the rotation center of the tipping electric cylinder 170, when the lifting electric cylinder 140 extends in position three, it drives the boom 130 to rise, and the bucket retraction limit block 121 of the bucket 120 tends to separate from the boom 130. The bucket 120 rotates counterclockwise relative to the boom 130, and the mechanism can move freely. When the lifting electric cylinder 140 shortens in position three, it drives the boom 130 to fall, and the bucket retraction limit block 121 of the bucket 120 tends to approach the boom 130. The bucket 120 rotates clockwise relative to the boom 130. Because the bucket closing limit block 121 has collided with the boom 130, the boom 130, rocker arm 150, connecting rod 160, and bucket 120 are locked together, restricting the movement of the mechanism. To allow the mechanism to descend from state three to state four, the tipping electric cylinder 170 must be appropriately shortened.

[0037] Traditional loaders use hydraulic cylinders to drive a six-bar linkage mechanism, requiring only an additional secondary relief valve in the multi-way valve. In case of interference, the pressure in the tipping cylinder changes, and the relief valve releases excess pressure to extend or retract the tipping cylinder, preventing interference. However, when the hydraulic cylinder is replaced with an electric cylinder, the interference problem still exists.

[0038] Please refer to Figures 1 to 6 To address the aforementioned issues, this embodiment also provides a control method for an all-electric loader, applied to the electric loader described in the above embodiments, to resolve the interference problem: The method includes: S1. During the movement of boom 130, acquire the first length parameter of lifting electric cylinder 140 and the second length parameter of tipping electric cylinder 170. S2. Determine whether the boom 130 will interfere with the bucket 120 during the movement based on the first length parameter and the second length parameter; S3. If the boom 130 interferes with the bucket 120 during movement, the bucket electric cylinder 170 is controlled to move the bucket 120 to eliminate the interference.

[0039] In this embodiment, during the movement of the boom 130, the first length parameter of the lifting electric cylinder 140 and the second length parameter of the tipping electric cylinder 170 are detected. Based on the first and second length parameters, it is determined whether the boom 130 will interfere with the tipping bucket during movement. When the boom 130 interferes with the bucket 120 during movement, the tipping electric cylinder 170 is controlled to move, thereby eliminating the interference. This eliminates the need for the operator to manually adjust the tipping electric cylinder 170 to avoid interference when operating the boom at the bucket retraction and tipping limits, making operation simpler.

[0040] Please refer to Figure 2 , Figure 3 and Figure 7 In this embodiment, step S2 includes: S21a. Determine whether the lifting electric cylinder 140 is extending; It should be noted that when the lifting electric cylinder 140 is detected to be extending, the system identifies it as the boom 130 rising.

[0041] S22a. If the lifting electric cylinder 140 is extending, determine whether the first length parameter is greater than or equal to the first preset threshold. It should be noted that the first preset threshold is a pre-set length value of the lifting electric cylinder 140, used to determine whether the boom 130 has risen to the vicinity of the area where interference may occur.

[0042] S23a. If the first length parameter is greater than or equal to the first preset threshold, then the first target length of the boom 130 and the tipping limit block 122 under interference conditions is calculated based on the first length parameter. The first target length is calculated by using the first length parameter, which makes it easier to obtain the critical value of the tipping electric cylinder 170, so as to make a comparison and judgment on whether there is interference in the later stage.

[0043] S24a. Determine whether the second length parameter is less than the first target length; By comparing the actual length of the current tipping electric cylinder 170 with the calculated first target length, it is easy to determine whether there is interference.

[0044] S25a. If the second length parameter is less than the first target length, it is determined that the boom 130 will interfere with the tipping bucket limit block 122 during the lifting process.

[0045] This embodiment can determine whether there will be interference between the boom 130 and the bucket 120 during the lifting process by the above method, which will facilitate the next step of solving the interference problem.

[0046] Please refer to Figure 2 , Figure 3 and Figure 7 After step S25a, step S3 includes the following sub-steps: S31a. If no driver control command corresponding to the tipping electric cylinder 170 is received, the tipping electric cylinder 170 is automatically extended to the first target length.

[0047] This embodiment can maintain the bucket 120 in its tipping limit state by means of the above method, and can also control the extension of the tipping electric cylinder 170 according to the change in the length of the lifting electric cylinder 140, thus solving the problem of interference between the lifting of the boom 130 and the bucket 120.

[0048] Please refer to Figure 2 , Figure 3 and Figure 7 In this embodiment, the first preset threshold is the difference between the length of the tipping electric cylinder at its minimum value and the length of the lifting electric cylinder 140 when it extends to the point where the tipping limit block 122 abuts against the boom 130 and the first safety threshold.

[0049] In this embodiment, setting the first preset threshold to the above value can both avoid interference and prevent movement during operation, and keep the bucket 120 as close as possible to its tipping limit.

[0050] It should be noted that the first safety threshold X1 can be set by the tester according to actual needs. The length a0 of the lifting electric cylinder 140 when the length of the tipping electric cylinder 170 is at its minimum and the lifting electric cylinder 140 extends to the point where the tipping limit block 122 abuts against the boom 130 is obtained by measurement. Overall, the value of the first preset threshold is a0-X1.

[0051] Please refer to Figure 2 , Figure 3 and Figure 7 In this embodiment, the calculation process of step S23a is as follows: ∠AOD=acos((OA²+OD²-AD²) / (2*OA*OD)); ∠BOC = ∠AOD - ∠AOB + ∠COD; b= ; M1 = b + Y1; Where O is the hinge center between the boom and the frame, A is the hinge center between the lifting electric cylinder and the frame, B is the hinge center between the dump electric cylinder and the frame, C is the hinge center between the dump electric cylinder and the rocker arm, and D is the hinge center between the lifting electric cylinder and the boom. BC is the distance between the hinge center B of the dump electric cylinder and the frame and the hinge center C of the dump electric cylinder and the rocker arm, and AD is the distance between the hinge center A of the lifting electric cylinder and the frame and the hinge center D of the lifting electric cylinder and the boom, i.e., the first length parameter. When the boom 130 abuts against the dump limit block 122, it can be considered that the boom 130, bucket 120, rocker arm 150, and connecting rod 160 are relatively fixed, thus making CD and ∠COD constant values. Y1 is the second safety threshold, and M1 is the first target length.

[0052] The length b of the tipping electric cylinder 170 in the tipping state (just interference) can be obtained from the above formula, which is the critical value. By adding a second safety threshold Y1 to b, interference can be avoided and dynamic control of the tipping electric cylinder 170 can be achieved, so that the bucket 120 is kept in the tipping limit state as much as possible.

[0053] It should be noted that OA is the fixed distance from point A to point O (the distance between the two hinge points on the frame 110), a fixed value determined by measurement. OD is the fixed distance from point O to point D (the distance from hinge point D on the boom 130 to the rotation center O), obtained by measurement. AD is the current length of the lifting electric cylinder 140 (the first length parameter), measured by a sensor. The size of ∠AOD can then be calculated using ∠AOD = acos((OA² + OD² - AD²) / (2 * OA * OD)).

[0054] Furthermore, ∠AOB is a constant, a fixed angle formed by points A, O, and B on the frame 110, obtained through measurement. ∠COD is a constant, obtained by measuring the tipping state when the length of the tipping electric cylinder is at its minimum and the lifting electric cylinder 140 extends to the point where the tipping limit block 122 abuts against the boom 130. Thus, the value of ∠BOC at the critical moment can be obtained.

[0055] Finally, by combining the length and angle relationships, the critical value b is obtained. Y1 is added to the critical value b to slightly increase the length of the tipping electric cylinder 170, thereby avoiding interference and realizing the lifting of the boom 130.

[0056] Please refer to Figure 4 , Figure 5 and Figure 8 In this embodiment, to address the interference problem that occurs when the boom 130 descends and the bucket 120 is in the bucket retraction limit state, step S2 further includes the following sub-steps: S21b, Determine whether the lifting electric cylinder 140 is shortening; It should be noted that when the lifting electric cylinder 140 is detected to be shortening, the system identifies it as the boom 130 lowering condition.

[0057] S22b If the lifting electric cylinder 140 is shortening, determine whether the first length parameter is less than or equal to the second preset threshold. It should be noted that the second preset threshold is a pre-set length value of the lifting electric cylinder 140, used to determine whether the boom 130 has been lowered to the vicinity of the area where interference may occur.

[0058] S23b. If the first length parameter is less than or equal to the second preset threshold, then the second target length of the boom 130 and the bucket limiting block 121 under interference conditions is calculated based on the first length parameter. The second target length is calculated using the first length parameter, which helps to obtain the critical value of the tipping electric cylinder 170, so that it can be compared and judged in the future to determine whether there is interference.

[0059] S24b: Determine whether the second length parameter is greater than the second target length; By comparing the actual length of the current tipping electric cylinder 170 with the calculated second target length, it is easy to determine whether there is interference.

[0060] S25b. If the second length parameter is greater than the second target length, it is determined that the boom 130 will interfere with the bucket limiting block 121 during the descent process.

[0061] This embodiment can determine whether there will be interference between the boom 130 and the bucket 120 during the lowering process by the above method, which will facilitate the next step of solving the interference problem.

[0062] Please refer to Figure 4 , Figure 5 and Figure 8 In this embodiment, the second preset threshold is the sum of the length of the tipping electric cylinder at its maximum value and the length of the lifting electric cylinder 140 corresponding to the time when the bucket closing limit block 121 and the boom 130 are shortened to the point where they are abutted and limited, and the third safety threshold.

[0063] In this embodiment, the second preset threshold is set to the above value to provide a safety margin and avoid collisions. When the length of the tipping electric cylinder 170 is at its maximum value and the lifting electric cylinder 140 is shortened to the point where the bucket closing limit block 121 abuts against the boom 130, the corresponding length of the lifting electric cylinder 140 is C0, and the third safety threshold is X2. The second preset threshold is C0 + X2.

[0064] In this embodiment, the calculation process of step S23b is as follows: ∠AOD=acos((OA²+OD²-AD²) / (2*OA*OD)) ∠BOC = ∠AOD - ∠AOB + ∠COD; d=

[0065] M2 = d - Y2; Where O is the hinge center between the boom and the frame, A is the hinge center between the lifting electric cylinder and the frame, B is the hinge center between the dump electric cylinder and the frame, C is the hinge center between the dump electric cylinder and the rocker arm, and D is the hinge center between the lifting electric cylinder and the boom. BC is the distance between the hinge center B of the dump electric cylinder and the frame and the hinge center C of the dump electric cylinder and the rocker arm, and AD is the distance between the hinge center A of the lifting electric cylinder and the frame and the hinge center D of the lifting electric cylinder and the boom, i.e., the first length parameter. Y2 is the fourth safety threshold, and M2 is the second target length. When the boom 130 abuts against the bucket limiting block 121, the boom 130, bucket 120, rocker arm 150, and connecting rod 160 can be considered relatively fixed, and CD and ∠COD can be considered constant values.

[0066] The calculation steps of S23b described above are basically the same as those of S23a, and will not be repeated in this embodiment.

[0067] In this embodiment, after step S25b, step S3 further includes the following steps: S31b If no driver control command corresponding to the tipper electric cylinder 170 is received, the tipper electric cylinder 170 is automatically shortened to release the interference.

[0068] Please refer to Figure 4 , Figure 5 and Figure 8 In this embodiment, S31b includes the following sub-steps: S31b1. If no driver control command corresponding to the tipping electric cylinder 170 is received, the tipping electric cylinder 170 is automatically controlled to shorten to the second target length.

[0069] That is, the length of the tipping electric cylinder 170 is shortened by active control, thereby avoiding limit interference when the lifting electric cylinder 140 is in operation.

[0070] Please refer to Figure 4 , Figure 5 and Figure 9 In another embodiment of this application, S31b includes the following sub-steps: S31b2 If both the driver's control command corresponding to the tipping electric cylinder 170 and the shortening command corresponding to the lifting electric cylinder 140 are received simultaneously, the brake of the tipping electric cylinder 170 is unlocked, and a holding torque is applied to the tipping electric cylinder 170 so that the torque on the tipping electric cylinder 170 is greater than the holding torque and shortens.

[0071] The difference between this step and the previous one is that the length change of the tipping electric cylinder 170 is passively adjusted. When the pressure on the tipping electric cylinder 170 due to interference exceeds the holding torque, the tipping electric cylinder 170 will be compressed and shortened, thereby avoiding interference. The holding torque can be determined through experiments and other methods, and can be changed by adjusting the parameters of the tipping electric cylinder 170.

[0072] Secondly, it should be noted that the driver's operating command for the tipping electric cylinder 170 is input by the driver through the operating mechanism. Not receiving a driver's operating command for the tipping electric cylinder 170 means the driver has not actively operated the tipping electric cylinder 170. If a driver's operating command for the tipping electric cylinder 170 is received, it means the driver is actively operating the tipping electric cylinder 170; in this case, the tipping electric cylinder 170 should act according to the driver's input command. The shortening command corresponding to the lifting electric cylinder 140 is input by the driver through the operating mechanism.

[0073] In summary, this embodiment acquires the first length parameter of the lifting electric cylinder 140 and the second length parameter of the tipping electric cylinder 170 during the movement of the boom 130. Based on the first and second length parameters, it determines whether the boom 130 will interfere with the bucket 120 during movement. If the boom 130 interferes with the bucket 120 during movement, the tipping electric cylinder 170 is controlled to move the bucket, thereby eliminating the interference. This eliminates the need for frequent control of the tipping electric cylinder 170 by the driver, simplifying operation. Compared to hydraulic drive, it eliminates the need for multiple energy conversions, thus improving energy efficiency.

[0074] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A control method for an all-electric loader, characterized in that, Applied to all-electric loaders, which include: A frame (110) having an electric drive system; The bucket (120) is equipped with a bucket retraction limit block (121) and a bucket tipping limit block (122). The boom (130) is hinged at one end to the frame (110) and at the other end to the bucket (120); A lifting electric cylinder (140) is provided, with one end of the lifting electric cylinder (140) hinged to the boom (130) and the other end hinged to the vehicle frame (110). The rocker arm (150) is hinged to the movable arm (130) at its middle part; The connecting rod (160) is hinged at one end to the bucket (120) and at the other end to the front end of the rocker arm (150); The tipping electric cylinder (170) is hinged at one end to the frame (110) and at the other end to the rear end of the rocker arm (150); When the tipping electric cylinder (170) drives the bucket (120) to rotate to the bucket retraction limit state, the bucket retraction limit block (121) abuts against the boom (130); When the tipping electric cylinder (170) drives the bucket (120) to rotate to the tipping limit state, the tipping limit block (122) abuts against the boom (130); The method includes: During the movement of the boom (130), the first length parameter of the lifting electric cylinder (140) and the second length parameter of the tipping electric cylinder (170) are obtained; Based on the first length parameter and the second length parameter, determine whether the boom (130) will interfere with the bucket (120) during the movement; If the boom (130) interferes with the bucket (120) during movement, the tipping electric cylinder (170) is controlled to move the bucket (120) to remove the interference.

2. The all-electric loader control method according to claim 1, characterized in that, The step of determining whether the boom (130) will interfere with the bucket (120) during movement based on the first length parameter and the second length parameter includes: During the extension process of the lifting electric cylinder (140), it is determined whether the first length parameter is greater than or equal to the first preset threshold. If the first length parameter is greater than or equal to the first preset threshold, then the first target length of the tipping electric cylinder (170) is calculated based on the first length parameter when the boom (130) and the tipping limit block (122) interfere with each other. Determine whether the second length parameter is less than the first target length; If the second length parameter is less than the first target length, it is determined that the boom (130) will interfere with the tipping bucket limit block (122) during the lifting process; The step of controlling the tilting electric cylinder (170) to move the bucket (120) to remove interference includes: If no driver control command is received for the corresponding tipping electric cylinder (170), the tipping electric cylinder (170) is automatically controlled to extend to the first target length.

3. The all-electric loader control method according to claim 2, characterized in that, The first preset threshold is the difference between the length of the tilting electric cylinder (170) at its minimum value and the length of the lifting electric cylinder (140) when the tilting limit block (122) and the boom (130) are extended to make the tilting limit block (122) abut against the boom (130) and the first safety threshold.

4. The all-electric loader control method according to claim 2, characterized in that, The step of calculating the first target length of the tilting electric cylinder (170) under interference conditions between the boom (130) and the tilting limit block (122) based on the first length parameter includes: ∠AOD=acos((OA²+OD²-AD²) / (2*OA*OD)); ∠BOC = ∠AOD - ∠AOB + ∠COD; b= ； M1 = b + Y1; Wherein, O is the hinge center between the boom (130) and the frame (110), A is the hinge center between the lifting electric cylinder (140) and the frame (110), B is the hinge center between the dump electric cylinder (170) and the frame (110), C is the hinge center between the dump electric cylinder (170) and the rocker arm (150), D is the hinge center between the lifting electric cylinder (140) and the boom (130), BC is the distance between the hinge centers between the dump electric cylinder (170) and the frame (110) and between the dump electric cylinder (170) and the rocker arm (150), AD is the first length parameter, Y1 is the second safety threshold, and M1 is the first target length.

5. The all-electric loader control method according to any one of claims 1-4, characterized in that, The step of determining whether the boom (130) will interfere with the bucket (120) during movement based on the first length parameter and the second length parameter further includes: During the shortening process of the lifting electric cylinder (140), it is determined whether the first length parameter is less than or equal to the second preset threshold. If the first length parameter is less than or equal to the second preset threshold, then the second target length of the tipping electric cylinder (170) is calculated based on the first length parameter when the boom (130) and the bucket closing limit block (121) interfere with each other. Determine whether the second length parameter is greater than the second target length; If the second length parameter is greater than the second target length, it is determined that the boom (130) will interfere with the bucket limiting block (121) during the descent process; The step of automatically controlling the tipping electric cylinder (170) to drive the bucket (120) to move, in order to eliminate interference, includes: If no driver control command is received for the corresponding tipping electric cylinder (170), the tipping electric cylinder (170) is automatically shortened to release the interference.

6. The all-electric loader control method according to claim 5, characterized in that, The second preset threshold is the sum of the length of the tipping electric cylinder (170) at its maximum value and the length of the lifting electric cylinder (140) when the bucket closing limit block (121) and the boom (130) are shortened to the point where the bucket closing limit block (121) and the boom (130) are in contact and limited, and the third safety threshold.

7. The all-electric loader control method according to claim 5, characterized in that, The step of calculating the second target length of the tipping electric cylinder (170) under interference conditions between the boom (130) and the bucket-closing limit block (121) based on the first length parameter includes: ∠AOD=acos((OA²+OD²-AD²) / (2*OA*OD)); ∠BOC = ∠AOD - ∠AOB + ∠COD; d= M2 = d - Y2; Wherein, O is the hinge center between the boom (130) and the frame (110), A is the hinge center between the lifting electric cylinder (140) and the frame (110), B is the hinge center between the tipping electric cylinder (170) and the frame (110), C is the hinge center between the tipping electric cylinder (170) and the rocker arm (150), D is the hinge center between the lifting electric cylinder (140) and the boom (130), and BC is the hinge center between the tipping electric cylinder (140) and the boom (130). The distance between the hinge center of the dump electric cylinder (170) and the frame (110) and the hinge center of the dump electric cylinder (170) and the rocker arm (150), AD is the distance between the hinge center of the lifting electric cylinder (140) and the frame (110) and the hinge center of the lifting electric cylinder (140) and the boom (130); the length of CD and ∠COD are constants; Y2 is the fourth safety threshold and M2 is the second target length.

8. The all-electric loader control method according to claim 7, characterized in that, The step of automatically controlling the tipping electric cylinder (170) to shorten in order to eliminate interference includes: If no driver control command is received for the tipping electric cylinder (170), the tipping electric cylinder (170) is automatically controlled to shorten to the second target length.

9. The all-electric loader control method according to claim 7, characterized in that, The step of automatically controlling the tipping electric cylinder (170) to shorten in order to eliminate interference includes: If both the driver's control command corresponding to the tipping electric cylinder (170) and the shortening command corresponding to the lifting electric cylinder (140) are received simultaneously, the brake of the tipping electric cylinder (170) is unlocked, and a holding torque is applied to the tipping electric cylinder (170) so that the tipping electric cylinder (170) shortens when the torque it can withstand is greater than the holding torque.

10. A fully electric loader, characterized in that, Includes a controller, which is electrically connected to the tipping electric cylinder (170) and the lifting electric cylinder (140), and the controller is capable of controlling the tipping electric cylinder (170) in accordance with the all-electric loader control method according to any one of claims 1-9.

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