Leveling system and leveling method suitable for large aerial work platform

Abstract

The invention discloses a leveling system and method suitable for a large aerial work platform, the leveling system comprises a detection device, a control device and an execution mechanism, the detection device is used for detecting the included angle between arms of the aerial work platform; the control equipment is used for calculating or converting data detected by the detection equipment through a control algorithm, outputting a current value of an element in the execution mechanism, and establishing a dynamic adjustment model of the aerial work platform according to the output current value; the execution mechanism is connected with the control device and used for leveling the aerial work platform. The method comprises the steps that included angles between arms of the aerial work platform are obtained; the included angle data between the arms are calculated or converted and output into corresponding current values through a control algorithm; and establishing a dynamic adjustment model of the aerial work platform according to the magnitude of the output current value, and leveling the aerial work platform according to a calculation result of the dynamic adjustment model. The leveling device is high in leveling precision, fast in response and good in stability.

Description

Technical Field

[0001] The present invention relates to the technical field of aerial work equipment, and particularly to a leveling system and a leveling method applicable to a large aerial work platform. Background Art

[0002] In the prior art, the leveling systems of aerial work platforms can be divided into two methods: one is active leveling from bottom to top. This leveling method measures the angles between the arms or the lengths of the hydraulic cylinders, and uses mechanical and hydraulic relationships to calculate the angles required for the working bucket to be in a horizontal position, and actively pushes the working bucket to this horizontal angle. The other is passive leveling from top to bottom. An inclination sensor is installed on the working bucket platform, and the inclination signal feedback by the sensor is used to adjust the working bucket to a horizontal position.

[0003] For the above two leveling methods, after years of practical application, combined with the optimization of manufacturing processes, hydraulic control, and mechanical structures, they basically meet the requirements of existing aerial work platforms. However, with the continuous increase in the height and load of the work platform, especially in large aerial work platforms, the first type of active leveling, due to the cumulative error after the increase in the number of boom hinge points, the clearance between the telescopic boom arms, the deformation of the boom, and the leakage of hydraulic cylinders, results in uneven and unstable leveling. For the second method of adjusting using the inclination sensor feedback, due to the increase in height, especially for aerial platforms above 70m, the wind will blow the platform to shake, and at the same time, the elastic deformation of the steel structure of the boom will also increase the shaking of the platform, resulting in jumps in the inclination sensor feedback value. Coupled with the inherent lag of its adjustment principle, it will cause jitter and instability in the leveling action. Summary of the Invention

[0004] To solve some or all of the technical problems existing in the above prior art, the present invention provides a leveling system and a leveling method applicable to a large aerial work platform, which have high leveling accuracy, fast response, and good stability for the aerial work platform.

[0005] The technical solution of the present invention is as follows:

[0006] In the first aspect, a leveling system applicable to a large aerial work platform is provided, including:

[0007] Detection equipment, which is arranged on the aerial work platform and is used to detect the angles between the arms of the aerial work platform, the angles between the arms and the platform, the extended lengths of the arms, and the weight of the working bucket;

[0008] A control device, which is connected to the detection device. A control algorithm is set in the control device, so that the control algorithm model calculates or converts the data detected by the detection device through the control algorithm and outputs the current value of the components in the actuator. And a dynamic adjustment model of the aerial work platform established according to the magnitude of the output current value is set in the control device, so that the actuator is controlled by the dynamic adjustment model to level the aerial work platform upward or downward;

[0009] An actuator, which is connected to the control device and is used to level the aerial work platform according to the calculation result of the dynamic adjustment model in the control device.

[0010] Further, in the above leveling system applicable to large aerial work platforms, the detection device includes:

[0011] An absolute angle encoder, which is arranged at the hinge points of each arm of the aerial work platform and is used to measure the included angle between each arm. The included angle includes the included angle between the arm and the turntable, the included angle between each folding arm, and the included angle between the arm and the work platform;

[0012] An absolute length encoder, which is arranged on each arm and is used to detect the extended length of each arm;

[0013] An inclination sensor, which is arranged on the workbench of the aerial work platform and is used to detect the inclination angle of the workbench relative to the horizontal plane;

[0014] A weighing sensor, which is arranged on the work bucket of the aerial work platform and is used to detect the weight of the work bucket.

[0015] Further, in the above leveling system applicable to large aerial work platforms, the actuator includes:

[0016] A control proportional valve, the oil inlet of which is connected to the first control end of the control device, and the oil outlet of which is connected to the second control end of the control device;

[0017] A switching valve, which includes a first solenoid valve and a second solenoid valve arranged in parallel. Among them, the first interface of the first solenoid valve is used as the first oil inlet of the switching valve and is connected to the first interface of the control proportional valve. The second interface of the first solenoid valve is used as the third oil inlet of the switching valve and is connected to the balance valve. The first interface of the second solenoid valve is used as the first oil outlet of the switching valve and is connected to the second interface of the control proportional valve. The second interface of the second solenoid valve is used as the third oil outlet and is connected to the balance valve;

[0018] A balance valve, wherein a first interface of the balance valve is connected to a third oil outlet of the switching valve, and a second interface of the balance valve is connected to a third oil inlet of the switching valve;

[0019] A leveling cylinder, wherein a rod chamber of the leveling cylinder is connected to an output port corresponding to the second interface of the balance valve, and a rodless chamber of the leveling cylinder is connected to an output port corresponding to the first interface of the balance valve.

[0020] Further, in the above leveling system applicable to a large aerial work platform, the actuator further includes a manual emergency control, a first interface of the manual emergency control is connected to an output pipeline of a second interface of the second solenoid valve in the switching valve as a second oil inlet of the switching valve, and a second interface of the manual emergency control is connected to an output pipeline of a second interface of the first solenoid valve in the switching valve as a second oil outlet of the switching valve.

[0021] Second, a leveling method applying the above leveling system applicable to a large aerial work platform is provided, including:

[0022] Obtaining the angles between the arms of the aerial work platform, the angles between the arms and the platform, the extended lengths of the arms, and the weight of the work bucket;

[0023] Calculating or converting the detected data of the angles between the arms, the angles between the arms and the platform, the extended lengths of the arms, and the weight of the work bucket through a control algorithm, and outputting corresponding current values;

[0024] Establishing a dynamic adjustment model of the aerial work platform according to the magnitudes of the output current values;

[0025] Leveling the aerial work platform upward or downward according to the calculation results of the dynamic adjustment model.

[0026] Further, in the above leveling method applicable to a large aerial work platform, establishing a dynamic adjustment model of the aerial work platform according to the magnitudes of the output current values includes:

[0027] An upward dynamic adjustment model, the upward dynamic adjustment model includes:

[0028]

[0029] Where: PWM UP represents the upward dynamic adjustment model of the aerial work platform, A represents the valve opening reference threshold, G1 represents the upward response algorithm formula, a represents the main arm amplification factor, b represents the folding arm amplification factor, c represents the flying arm amplification factor, represents the relative angle between the arms, represents the main arm linear change trend function, Represents the folding arm linear change trend function, Represents the flying arm linear change trend coefficient, PWM BoomUp Represents the upward current of the main boom amplitude variation of the aerial work platform, PWM BoomDown Represents the downward current of the main boom amplitude variation of the aerial work platform, PWM FoldUp Represents the upward current of the folding boom amplitude variation of the aerial work platform, PWM FoldDown Represents the downward current of the folding boom amplitude variation of the aerial work platform, PWM FlyUp Represents the upward current of the flying boom amplitude variation of the aerial work platform, PWM FlyDown Represents the downward current of the flying boom amplitude variation of the aerial work platform, d represents the level amplifier coefficient, θ represents the inclination angle of the work platform relative to the horizontal plane, θ0 represents the reference angle, the reference angle represents the feedback value of the inclinometer when the work bucket is horizontal, m(θ - θ0) represents the coefficient linear function with the angle difference as the input variable, e represents the weight amplification coefficient, and T represents the weight of the work bucket.

[0030] Furthermore, in the above leveling method applicable to large aerial work platforms, according to the magnitude of the output current value, establishing the dynamic adjustment model of the aerial work platform includes:

[0031] The downward dynamic adjustment model, and the downward dynamic adjustment model is determined according to the upward dynamic adjustment model and the actual situation of the aerial work platform.

[0032] Furthermore, in the above leveling method applicable to large aerial work platforms, the change trend coefficient is obtained by the following method:

[0033] Adopt the point plotting method, fit the mechanical structure calculation relationship, and plot the corresponding points;

[0034] Use the included angle as the scale, and take the derivative of the cylinder length according to the plotted corresponding points;

[0035] Take the result obtained by the derivative as the change trend coefficient.

[0036] The main advantages of the technical solution of the present invention are as follows:

[0037] A leveling system and method applicable to large aerial work platforms according to the present invention obtain various parameters during the operation of the aerial work platform through detection devices, convert the obtained detection parameters into their corresponding current values through a control device, and establish a dynamic adjustment model for adjusting the aerial work platform to move upward or downward based on the converted current values. The aerial work platform is leveled upward or downward according to the calculation results of the dynamic adjustment model. Thus, by converting the adjustment method into a method of detecting current values and establishing a model, the present invention makes the adjustment more accurate, avoids the problem of inaccurate adjustment caused by the shaking of the aerial work platform due to wind and its own factors, and eliminates the problem of unnecessary frequent adjustment caused by the interference of wind force and mechanical elasticity on the work bucket. At the same time, the adjustment structure of the present invention is simple, has good leveling stability, high precision, and fast response speed, can better ensure the safety of the operators and operating equipment on the aerial work platform, as well as the safety of the aerial platform itself, avoid damage to the aerial work equipment, and also avoid the risk of falling objects caused by poor leveling effect and resulting in aerial falling objects. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of the present invention, and the illustrative embodiments and descriptions thereof are used to explain the present invention without unduly limiting the present invention. In the drawings:

[0039] Figure 1 is a schematic diagram of the overall structure of a leveling system applicable to large aerial work platforms provided by an embodiment of the present invention;

[0040] Figure 2 is Figure 1 an enlarged schematic diagram of part A in;

[0041] Figure 3 is Figure 1 an enlarged schematic diagram of part B in;

[0042] Figure 4 is Figure 1 an enlarged schematic diagram of part C in;

[0043] Figure 5 is Figure 1 an enlarged schematic diagram of part D in;

[0044] Figure 6 is a schematic diagram of the structure of an actuator in a leveling system applicable to large aerial work platforms provided by an embodiment of the present invention;

[0045] Figure 7 is a schematic diagram of the structure of a leveling mechanism in a leveling system applicable to large aerial work platforms provided by an embodiment of the present invention;

[0046] Figure 8 A schematic flow chart of a leveling method applicable to a large aerial work platform provided in one embodiment of the present invention;

[0047] Figure 9 A schematic diagram of a corresponding point diagram drawn based on the calculated relationship between each arm amplitude angle and cylinder extension in a leveling method applicable to a large aerial work platform provided by one embodiment of the present invention;

[0048] Figure 10 4. Schematic diagram of the current and flow characteristic curve of the electromagnetic proportional leveling valve in a leveling method applicable to a large aerial work platform provided in one embodiment of the present invention.

[0049] Description of reference numerals:

[0050] 1. Main boom luffing cylinder; 2. Folding boom luffing cylinder; 3. Flying boom luffing cylinder; 4. Working bucket leveling cylinder; 5. Main boom luffing angle encoder; 6. Folding boom luffing angle encoder; 7. Flying boom luffing angle encoder; 8. Inclination sensor; 9. Weighing sensor; 10. Control proportional valve; 11. Switching valve; 12. Manual emergency control; 13. Balancing valve; 14. Leveling cylinder; 15. Four-bar linkage; 16. Working bucket support structure. DETAILED DESCRIPTION

[0051] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments of the present invention and corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0052] The following is combined with Figure 1 -Attached Figure 10 , describes in detail the technical solution provided by the embodiments of the present invention.

[0053] In order to clearly and completely illustrate the technical solution of the present invention, a brief introduction is given to the aerial work platform provided in the embodiment of the present invention. The aerial work platform provided in the embodiment of the present invention includes a main arm luffing mechanism, a folding arm luffing mechanism, a flying arm luffing mechanism and a working bucket leveling mechanism. The corresponding structures are as follows: Figures 1-5 As shown, the above-mentioned institutions correspond to Figures 2-5 The structure of the aerial work platform corresponds to the Figure 1The positions of A - D correspond to the main boom luffing cylinder 1, folding boom luffing cylinder 2, fly boom luffing cylinder 3, and working bucket leveling cylinder 4 on the main boom luffing mechanism, folding boom luffing mechanism, fly boom luffing mechanism, and working bucket leveling mechanism, which are used to level the working bucket alone or in combination with multiple cylinders.

[0054] The purpose of the present invention is to provide a leveling system and method applicable to large aerial work platforms, so that the method and system of the present invention can solve the problem of unstable leveling of large climbing platforms based on existing sensors and mechanical structures without adding redundant special hardware devices.

[0055] In the first aspect, as shown in the attached Figure 1 - attached Figure 7 figures, the embodiments of the present invention provide a leveling system applicable to large aerial work platforms, which includes: detection equipment, control equipment, and an actuator, where:

[0056] The detection equipment is arranged on the aerial work platform and is used to detect the angles between the arms of the aerial work platform, the angles between the arms and the platform, the extended lengths of the arms, and the weight of the working bucket; the control equipment is connected to the detection equipment, and a control algorithm is set in the control equipment, so that the control algorithm model calculates or converts the data detected by the detection equipment through the control algorithm and outputs the current values of the components in the actuator, and a dynamic adjustment model of the aerial work platform established according to the magnitude of the output current value is set in the control equipment, so that the actuator is controlled through the dynamic adjustment model to level the aerial work platform upward or downward; the actuator is connected to the control equipment, and the actuator is used to level the aerial work platform according to the calculation result of the dynamic adjustment model in the control equipment.

[0057] Further, referring to Figures 1-5 , in an embodiment of the present invention, the detection equipment includes: an absolute angle encoder, an absolute length encoder, an inclination sensor 8, and a weighing sensor 9, where:

[0058] The absolute encoder is arranged at the hinge points of the arms of the aerial work platform and is used to measure the angles between the arms. Its measurement principle includes the wire - type relative length measurement principle. The angles include the angles between the arm and the turntable, the angles between the folding arms, and the angles between the arm and the work platform; the absolute length encoder is arranged on each arm and is used to detect the extended length of each arm; the inclination sensor 8 is arranged on the workbench of the aerial work platform and is used to detect the inclination angle of the workbench relative to the horizontal plane; the weighing sensor 9 is arranged on the working bucket of the aerial work platform and is used to detect the weight of the working bucket.

[0059] As an example, the absolute value encoder includes a main boom luffing angle encoder 5, a folding boom luffing angle encoder 6, and a fly boom luffing angle encoder, and the above-mentioned main boom luffing angle encoder 5, folding boom luffing angle encoder 6, and fly boom luffing angle encoder are correspondingly arranged at the hinge points of the main boom and the folding boom, and the folding boom and the fly boom of the aerial work platform. The included angle between the arms measured by the absolute value angle encoder is represented by α1 to α n is represented, and the extended lengths of each section of the boom measured by the absolute value length encoder are represented by l1 to l n is represented, the inclination angle of the working platform relative to the horizontal plane measured by the inclination sensor 8 is represented by θ, and the weight of the working bucket measured by the weighing sensor 9 is represented by T.

[0060] In order to make the data detected by the above-mentioned detection equipment more accurate, and thus make the leveling of the aerial work platform more accurate, the number of the above-mentioned various detection equipment is set to multiple, so that the same parameter is detected by multiple detection equipment, thereby ensuring the accuracy of the detection.

[0061] At the same time, in order to facilitate data calculation and acquisition, the average value of the detection values of the detection equipment with the same detection parameter is used as the detection result of a detection part.

[0062] In order to improve the detection accuracy, and at the same time for the weight of the aerial work platform to make the structure simple, the detection equipment at each detection position is set to at least two or two.

[0063] In some optional implementation manners of this embodiment, the functions of the control algorithm or the control algorithm model include substituting the sensor detection data into the parametric model for calculation, and the output is the current value of the proportional valve of the actuator.

[0064] As an example, the control algorithm is set in the controller. The controller has functions of analog-to-digital acquisition of data, communication interface, logic calculation, and digital-to-analog output. When the controller performs the above corresponding data processing, the controller calls the corresponding control algorithm to enable the control algorithm to convert the corresponding data. After the control algorithm converts the detected data into current data, a corresponding dynamic adjustment model is established according to the converted current data.

[0065] As an example, the detection equipment can also be set as an industrial personal computer.

[0066] Further, referring to Figure 6 , in an embodiment of the present invention, the actuator includes: a control proportional valve 10, a switching valve 11, a balance valve 13, and a leveling oil cylinder 14, where:

[0067] The oil inlet of the control proportional valve 10 is connected to the first control end of the control device, and the oil outlet of the control proportional valve 10 is connected to the second control end of the control device; the switching valve 11 includes a first solenoid valve and a second solenoid valve distributed in parallel. Among them, the first interface of the first solenoid valve serves as the first oil inlet of the switching valve 11 and is connected to the first interface of the control proportional valve 10, the second interface of the first solenoid valve serves as the third oil inlet of the switching valve 11 and is connected to the balance valve 13, the first interface of the second solenoid valve serves as the first oil outlet of the switching valve 11 and is connected to the second interface of the control proportional valve 10, and the second interface of the second solenoid valve serves as the third oil outlet and is connected to the balance valve 13; the first interface of the balance valve 13 is connected to the third oil outlet of the switching valve 11, and the second interface of the balance valve 13 is connected to the third oil inlet of the switching valve 11; the rod chamber of the leveling cylinder 14 is connected to the output port corresponding to the second interface of the balance valve 13, and the rodless chamber of the leveling cylinder 14 is connected to the output port corresponding to the first interface of the balance valve 13.

[0068] In the embodiment of the present invention, due to its characteristics of large flow rate and large current range, the control proportional valve 10 is used to control the leveling speed in the embodiment of the present invention. The balance valve 13 functions as an interlock protection in the embodiment of the present invention, and the switching valve 11 is used to switch between manual and automatic modes.

[0069] Further, referring to Figure 6 , in an embodiment of the present invention, the actuator further includes a manual emergency control 12. The first interface of the manual emergency control 12 serves as the second oil inlet of the switching valve 11 and is connected to the output pipeline of the second interface of the second solenoid valve in the switching valve 11. The second interface of the manual emergency control 12 serves as the second oil outlet of the switching valve 11 and is connected to the output pipeline of the second interface of the first solenoid valve in the switching valve 11.

[0070] In order to enable the manual emergency control 12 to quickly and safely adjust or brake the aerial work platform, the manual emergency control 12 needs to be operated with both hands, so that during the braking process of the aerial work platform, it can completely break away from the original hydraulic power and boom pipeline through the manual emergency control 12.

[0071] Specifically, the components and connection relationships of the actuator in the embodiment of the present invention are as shown in the appendix Figure 6 shown.

[0072] In some optional implementation manners of this embodiment, the manual emergency control 12 includes a lever or a push rod, etc.

[0073] For the convenience of emergency operation, improve the efficiency and accuracy of emergency operation, the manual emergency control 12 can be set as an emergency button. When the emergency button is pressed, it plays an emergency control role to achieve the purpose of emergency control.

[0074] Furthermore, in the embodiments of the present invention, a leveling mechanism is further included, such as Figure 7 shown. The leveling mechanism includes the above-mentioned leveling oil cylinder 14, four-link mechanism 15 and working bucket support structure 16. When adjusting the working bucket, the leveling oil cylinder 14 pushes the four-link mechanism 15 to rotate the working bucket support, so as to achieve the purpose of adjusting the angle of the working bucket.

[0075] Secondly, as Figure 8 shown, the present invention also provides a leveling method for applying the leveling system of a leveling system suitable for a large aerial work platform described above. The method includes the following steps S1-S4:

[0076] Step S1: Obtain the included angles between the arms of the aerial work platform, the included angles between the arms and the platform, the extended lengths of the arms, and the weight of the working bucket;

[0077] As an example, the included angles between the arms of the aerial work platform, the included angles between the arms and the platform, the extended lengths of the arms, and the weight of the working bucket are obtained by an absolute angle encoder, an absolute length encoder, an inclination sensor 8 and a weighing sensor 9 respectively.

[0078] Step S2: Calculate or convert the detected data of the included angles between the arms, the included angles between the arms and the platform, the extended lengths of the arms, and the weight of the working bucket through a control algorithm, and output the corresponding current value;

[0079] It should be noted that the above control algorithm is determined according to actual needs. The number and type of algorithms and the calculation method of the control algorithm are all commonly used algorithm models in the prior art. When obtaining the converted data, only the obtained data needs to be input into the algorithm model, or the algorithm model calls the corresponding data, and the corresponding current value can be output.

[0080] As an example, for example, through the linear regression algorithm: I = w·S + b, where I represents the output current value, w represents the weight (slope), S represents the input sensor data, and b represents the bias (intercept). Through the above formula, the purpose of obtaining the sensor data and outputting the corresponding current value can be achieved.

[0081] As an example, for example, the polynomial regression algorithm: I = w2·S 2 + w1·S + b, where I represents the output current value, w represents the weight (slope), S represents the input sensor data, and b represents the bias (intercept). Through the above formula, the purpose of obtaining the sensor data and outputting the corresponding current value can also be achieved.

[0082] As an example, for instance, through a neural network model, the input layer of the neural network model is set to 1 node, i.e., sensor data, the hidden layer is set to 3 nodes, ReLU activation is used, the output layer is set to 1 node, linear activation is used, and the corresponding current value of the input is output.

[0083] Step S3: Establish a dynamic adjustment model for the aerial work platform according to the magnitude of the output current value;

[0084] Specifically, establishing a dynamic adjustment model for the aerial work platform according to the magnitude of the output current value includes: an upward dynamic adjustment model and a downward dynamic adjustment model. Among them, the upward dynamic adjustment model includes:

[0085]

[0086] Among them: PWM UP represents the upward dynamic adjustment model of the aerial work platform, A represents the valve opening reference threshold, G1 represents the upward response algorithm formula, a represents the main boom amplification coefficient, b represents the folding boom amplification coefficient, c represents the fly boom amplification coefficient, represents the relative angle between the arms, represents the main boom linear change trend function, represents the folding boom linear change trend function, represents the fly boom linear change trend coefficient, PWM BoomUp represents the upward current of the main boom amplitude variation of the aerial work platform, PWM BoomDown represents the downward current of the main boom amplitude variation of the aerial work platform, PWM FoldUp represents the upward current of the folding boom amplitude variation of the aerial work platform, PWM FoldDowh represents the downward current of the folding boom amplitude variation of the aerial work platform, PWM FlyUp represents the upward current of the fly boom amplitude variation of the aerial work platform, PWM FlyDown represents the downward current of the fly boom amplitude variation of the aerial work platform, d represents the level amplifier coefficient, θ represents the inclination angle of the work platform relative to the horizontal plane, θ0 represents the reference angle, and the reference angle represents the feedback value of the inclinometer when the work bucket is horizontal. m(θ - θ0) represents a coefficient linear function with the angle difference as the input variable, e represents the weight amplification coefficient, and T represents the weight of the work bucket.

[0087] Among them, the downward dynamic adjustment model is determined according to the upward dynamic adjustment model and the actual situation of the aerial work platform.

[0088] Exemplarily, in combination with Figure 1 , based on the inherent change direction of the mechanical structure, for example, only PWM BoomUp - PWM BoomDown> 0; At this time, only when the main boom moves upward (clockwise rotation), other mechanisms do not move, and the working platform will necessarily tilt downward; while when PWM UP > 0, it makes the platform move upward automatically. For another example, at certain times, PWM UP = -PWM Down .

[0089] Therefore, the downward dynamic adjustment of the model PWM DOWN cannot be generalized, nor can PWM UP be used for substitution. It needs to be determined according to the upward dynamic adjustment model and the actual situation of the aerial work platform.

[0090] Step S4: Level the aerial work platform upward or downward according to the calculation result of the dynamic adjustment model.

[0091] Since after a certain height of the large aerial work platform, the wind force interferes with the platform stability, increasing the disturbance of the sensor, the hydraulic valve action feedback current of the luffing mechanism that affects the horizontal of the working bucket mechanism in the whole vehicle mechanism is used as the monitoring item. If there is no action and the feedback value of the working bucket inclination sensor 8 is within the set range, no working bucket leveling action is performed. This eliminates unnecessary frequent adjustments caused by the interference of wind force and mechanical elasticity on the working bucket.

[0092] Analyzing the working direction of the aerial work platform, the reverse direction output is blocked.

[0093] The leveling direction of the working bucket is nothing more than upward or downward. According to the movement direction of each arm, the adjustment direction that the working bucket should have can be predicted. For example:

[0094] If the main boom luffing mechanism moves upward, the working bucket moves downward, and the working bucket should be adjusted upward. On the contrary, it is adjusted downward.

[0095] If the folding boom luffing mechanism moves upward, the working bucket moves upward, and the working bucket should be adjusted downward. On the contrary, it is adjusted upward.

[0096] If the fly boom luffing mechanism moves upward, the working bucket moves upward, and the working bucket should be adjusted downward. On the contrary, it is adjusted upward.

[0097] On the basis of this prediction, the current output in the reverse direction is blocked, so that the working bucket is adjusted only in one direction, thereby improving the response and reducing the jitter.

[0098] Furthermore, referring to Figure 9 , Figure 9 is a schematic diagram of drawing the corresponding point diagram according to the calculation relationship between the luffing angle of each arm and the cylinder elongation amount in a leveling method for a large aerial work platform provided by an embodiment of the present invention. In an embodiment of the present invention, the change trend coefficient is obtained by the following method:

[0099] Using the point - plotting method, fit the calculation relationship of the mechanical structure and draw the corresponding points; taking the included angle as a scale, derive the length of the oil cylinder based on the drawn corresponding points; use the result of the derivation as the change - trend coefficient.

[0100] Specifically, due to the differences in mechanical structures, the relationship between the length of the oil cylinder extending and the change in the luffing angle cannot be calculated using an ordinary linear formula. Since it is non - linear and even irregular, the point - plotting method is used to fit a corresponding calculation relationship. In the figure, the X - axis is the serial number of the corresponding points, which has no actual meaning and can be understood as the first point, the second point, etc. The Y - axis represents the actual length value for the length and the corresponding angle value for the angle.

[0101] Exemplarily, when the X - axis is 1, the corresponding angle is 10 and the length of the oil cylinder is 1100.

[0102] As an example, based on the calculation relationship between the luffing angle of each arm and the elongation of the oil cylinder, draw the corresponding points.

[0103] Based on the mechanical structure, the corresponding points can be calculated and drawn, and taking the included angle as a scale, derive the length of the oil cylinder to obtain the change - trend coefficient. As its application.

[0104] Such as Figure 10 shown, Figure 10 is a schematic diagram of the current - flow characteristic curve of the electromagnetic proportional leveling valve in a leveling method applicable to a large - scale aerial work platform provided by an embodiment of the present invention. Based on the current - flow characteristics of the electromagnetic proportional leveling valve, determine the starting currents A and B and draw the corresponding points during the change.

[0105] In order to avoid over - adjustment of the aerial work platform by using the leveling method of the leveling system applicable to the large - scale aerial work platform of the present invention, an over - adjustment threshold can also be set according to the inclination sensor 8.

[0106] Specifically, when the boom is in motion, the current of the working - bucket leveling proportional valve has exceeded the maximum current, but the working - bucket leveling still cannot keep up and reaches the set threshold. Send an over - adjustment signal to the controller for speed - reduction protection control.

[0107] In addition, a protection threshold can also be set according to the inclination sensor 8.

[0108] When the angle detected by the inclinometer exceeds the protection angle, send a protection signal to the controller. For example, output the finally defined command to the actuator through the controller.

[0109] The principle of a leveling system and a leveling method applicable to a large - scale aerial work platform of the present invention is described as follows: Specifically:

[0110] By adopting detection equipment to obtain various parameters of the aerial work platform's operation process, the acquired detection parameters are converted into their corresponding current values through the control equipment, and a dynamic adjustment model for adjusting the aerial work platform upward or downward is established through the converted current value. The aerial work platform is leveled upward or downward through the calculation result of the dynamic adjustment model. Therefore, the present invention makes the adjustment more accurate by converting the adjustment method into a method of detecting current values and establishing a model, avoiding the problem of inaccurate adjustment caused by wind blowing and the aerial work platform's own factors, and eliminating the problem of unnecessary frequent adjustments caused by the interference of wind and mechanical elasticity on the work bucket. At the same time, the adjustment structure of the present invention is simple, the leveling stability is good, the precision is high, and the response speed is fast, which can better ensure the safety of workers and working equipment on the aerial work platform, as well as the safety of the aerial platform itself, avoid damage to the aerial work equipment, and avoid the risk of materials falling due to poor leveling effect, resulting in falling objects from high altitude.

[0111] In summary, the leveling system and leveling method for a large aerial work platform of the present invention have at least the following technical effects:

[0112] Static stabilization: When the boom is in a static working condition, it monitors and protects the working bucket in real time to prevent shaking and misoperation caused by frequent adjustments.

[0113] In the dynamic process adjustment, the feedback current of the valve is used as the action reference, which means that the movement direction of the boom is accurately captured without tilting or overshooting caused by active leveling.

[0114] The parameterized control algorithm has a wide range of adaptability and is easy to expand, fully covering the working conditions of all aerial platforms.

[0115] Complete protection mechanism. Two safety protections are set: overshoot threshold and protection threshold, and it is combined with reverse blocking output function, hydraulic system balance valve 13 protection function, and manual emergency function.

[0116] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In addition, "front", "back", "left", "right", "upper" and "lower" in this document are all referenced to the placement states shown in the accompanying drawings.

[0117] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A leveling system applicable to large aerial work platforms, characterized in that, Comprising: A detection device, which is arranged on the aerial work platform and is used to detect the included angle between the arms of the aerial work platform, the included angle between the arm and the platform, the extended length of each arm, and the weight of the working bucket; A control device, which is connected to the detection device. A control algorithm is set in the control device, so that the control algorithm model calculates or converts the data detected by the detection device through the control algorithm and outputs the current value of the components in the actuator. And a dynamic adjustment model of the aerial work platform established according to the magnitude of the output current value is set in the control device, so as to control the actuator to level the aerial work platform upward or downward through the dynamic adjustment model; An actuator, which is connected to the control device and is used to level the aerial work platform according to the calculation result of the dynamic adjustment model in the control device.

2. The leveling system for a large aerial work platform according to claim 1, wherein, The detection device includes: An absolute angle encoder, which is arranged at the hinge points of the arms of the aerial work platform and is used to measure the included angle between the arms. The included angle includes the included angle between the arm and the turntable, the included angle between the folding arms, and the included angle between the arm and the work platform; An absolute length encoder, which is arranged on each arm and is used to detect the extended length of each arm; An inclination sensor, which is arranged on the workbench of the aerial work platform and is used to detect the inclination angle of the workbench relative to the horizontal plane; A weighing sensor, which is arranged on the working bucket of the aerial work platform and is used to detect the weight of the working bucket.

3. The leveling system for a large aerial work platform according to claim 1, characterized in that, The actuator includes: A control proportional valve, the oil inlet of which is connected to the first control end of the control device, and the oil outlet of which is connected to the second control end of the control device; A switching valve, which includes a first solenoid valve and a second solenoid valve arranged in parallel. Among them, the first interface of the first solenoid valve is used as the first oil inlet of the switching valve and is connected to the first interface of the control proportional valve. The second interface of the first solenoid valve is used as the third oil inlet of the switching valve and is connected to the balance valve. The first interface of the second solenoid valve is used as the first oil outlet of the switching valve and is connected to the second interface of the control proportional valve. The second interface of the second solenoid valve is used as the third oil outlet and is connected to the balance valve; A balance valve, the first interface of which is connected to the third oil outlet of the switching valve, and the second interface of which is connected to the third oil inlet of the switching valve; A leveling oil cylinder, the rod chamber of which is connected to the output port corresponding to the second interface of the balance valve, and the rodless chamber of which is connected to the output port corresponding to the first interface of the balance valve.

4. A leveling system applicable to a large-scale aerial work platform according to claim 3, characterized in that, The actuator further includes a manual emergency control, the first interface of which is used as the second oil inlet of the switching valve and is connected to the output pipeline of the second interface of the second solenoid valve in the switching valve. The second interface of the manual emergency control is used as the second oil outlet of the switching valve and is connected to the output pipeline of the second interface of the first solenoid valve in the switching valve.

5. A leveling method for a leveling system applicable to a large aerial work platform according to any one of claims 1-4, characterized in that, Comprising: Obtain the angles between the arms of the aerial work platform, the angles between the arms and the platform, the extended lengths of the arms, and the weight of the work bucket; Calculate or convert the data of the angles between the arms, the angles between the arms and the platform, the extended lengths of the arms, and the weight of the work bucket detected through the control algorithm, and output the corresponding current values; Establish a dynamic adjustment model of the aerial work platform according to the magnitudes of the output current values; Level the aerial work platform upward or downward according to the calculation results of the dynamic adjustment model.

6. A leveling method applicable to a large high-altitude operation platform according to claim 5, characterized in that, Establishing a dynamic adjustment model of the aerial work platform according to the magnitudes of the output current values includes: An upward dynamic adjustment model, and the upward dynamic adjustment model includes: Among them: PWM UP represents the upward dynamic adjustment model of the aerial work platform, A represents the valve opening reference threshold, G1 represents the upward response algorithm formula, a represents the main boom amplification factor, b represents the folding boom amplification factor, c represents the fly boom amplification factor, represents the relative angle between each arm, represents the main boom linear change trend function, represents the folding boom linear change trend function, represents the fly boom linear change trend coefficient, PWM BoomUp represents the upward current of the main boom amplitude variation of the aerial work platform, PWM BoomDown represents the downward current of the main boom amplitude variation of the aerial work platform, PWM FoldUp represents the upward current of the folding boom amplitude variation of the aerial work platform, PWM FoldDown represents the downward current of the folding boom amplitude variation of the aerial work platform, PWM FlyUp represents the upward current of the fly boom amplitude variation of the aerial work platform, PWM FlyDown represents the downward current of the fly boom amplitude variation of the aerial work platform, d represents the level amplifier factor, θ represents the inclination angle of the work platform relative to the horizontal plane, θ0 represents the reference angle, and the reference angle represents the feedback value of the inclinometer when the work bucket is horizontal. m(θ - θ0) represents a coefficient linear function with the angle difference as the input variable, e represents the weight amplification factor, and T represents the weight of the work bucket.

7. A leveling method applicable to a large-scale aerial work platform according to claim 5, characterized in that, Establishing a dynamic adjustment model of the aerial work platform according to the magnitudes of the output current values includes: A downward dynamic adjustment model, and the downward dynamic adjustment model is determined according to the upward dynamic adjustment model and the actual situation of the aerial work platform.

8. A leveling method applicable to a large-scale aerial work platform according to claim 6, characterized in that The change trend coefficient is obtained through the following method: Adopt the point plotting method, fit the calculation relationship of the mechanical structure, and plot the corresponding points; Taking the angle as the scale, take the derivative of the cylinder length according to the plotted corresponding points; Take the result obtained by the derivative as the change trend coefficient.

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