Hoist synchronization control method and device, crane and storage medium

Abstract

The present disclosure discloses a hoist synchronous control method and device, a crane and a storage medium, and relates to the field of engineering machinery. The method comprises: for a multi-hoist working condition, in the case that the hoist load is between an empty load and a heavy load, determining a motor displacement control current value corresponding to any one hoist motor based on a preset electric control pressure cut-off value; and outputting the motor displacement control current value to each hoist motor to control each hoist motor to have the same displacement. According to the present disclosure, each hoist motor has the same displacement when the pressure is cut off, and the multi-hoist synchronous control can be better achieved. In addition, since the preset electric control pressure cut-off value ensures that the motor works at the minimum displacement that can work under the current load, the speed of the motor can be improved while the double-hoist or multi-hoist synchronization is ensured, and the system efficiency is improved.

Description

Technical Field

[0001] This disclosure relates to the field of engineering machinery, and more particularly to a hoisting synchronization control method, device, crane, and storage medium. Background Technology

[0002] Within a safe pressure range and with a fixed input flow rate, a smaller motor displacement results in a faster rotation speed. The motor pressure cut-off function is highly beneficial for improving hoisting efficiency and ensuring hoisting functionality. Large-tonnage crane hoisting systems utilize electrically controlled proportional-variable motors with pressure cut-off to meet the speed control requirements of different loads.

[0003] For large-tonnage cranes using dual-lifting winches, synchronization of the two winches is crucial; otherwise, hook misalignment can affect construction, damage the wire rope or hook, and lead to accidents. Besides the input flow rate, winch bottom diameter, and wire rope diameter, the main factors affecting dual-winch synchronization include the consistency of motor displacement. Motor displacement is primarily affected by the displacement control signal and the motor pressure cut-off value. External errors such as winch and wire rope bottom diameters are easily detected, controlled, and corrected. Disparities in displacement control caused by the motor displacement control signal can also be corrected through closed-loop feedback. However, the motor pressure cut-off function automatically controls its own displacement based on system pressure. The entire displacement adjustment process is a mechanical-hydraulic automatic control, guaranteed by component manufacturing and functional debugging tests. In reality, the factors such as the cut-off valve and spring of the motor pressure cut-off displacement control mechanism, and the frictional resistance of each mating surface, cannot be completely identical. Displacement adjustment responses also vary. Therefore, the displacement controlled by the pressure cut-off value of different motors is difficult to be completely consistent. Furthermore, the actual loads borne by the two hoisting motors may differ, resulting in differences in the actual working pressure of the different motors. This can lead to a situation where one motor remains unchanged while the other motor automatically changes pressure or the two motors change to different degrees, resulting in a lack of synchronization.

[0004] Currently, high-precision, high-pressure, and high-reliability electro-hydraulic piston motors remain a technical challenge. All the winch motors used for synchronous double winches in large-tonnage cranes in China are imported brands, but this still cannot avoid the problem of inconsistent motor displacement. Therefore, how to solve the asynchrony problem caused by motor pressure cut-off in practical applications is of great significance for making up for the shortcomings of domestic high-precision component processing and manufacturing level and realizing domestic application substitution. Summary of the Invention

[0005] One technical problem this disclosure aims to solve is to provide a hoisting synchronization control method, device, crane, and storage medium that can realize multi-hoisting synchronization control.

[0006] According to one aspect of this disclosure, a hoisting synchronization control method is proposed, comprising: for multi-hoisting working conditions, when the hoisting load is between no load and heavy load, determining the motor displacement control current value corresponding to any hoisting motor based on a preset electrical control pressure cutoff value, wherein the preset electrical control pressure cutoff value is less than the mechanical pressure cutoff value; and outputting the motor displacement control current value to each hoisting motor to control each hoisting motor to have the same displacement.

[0007] In some embodiments, determining the motor displacement control current value corresponding to any hoist motor includes: determining the winding diameter of the outermost lifting rope of any hoist at the current moment; and calculating the motor displacement control current value corresponding to any hoist motor based on the tension of the lifting rope, the winding diameter, and the preset electronic control pressure cut-off value of each hoist.

[0008] In some embodiments, calculating the motor displacement control current value corresponding to any hoist motor includes: calculating the motor displacement control current value corresponding to any hoist motor based on the functional relationship between the motor displacement control current value, the torque of any hoist, and the preset electronic control pressure cut-off value, wherein the torque is the product of the tension of the hoisting rope and the winding diameter.

[0009] In some embodiments, the motor displacement control current value is linearly negatively related to the torque of any winch and positively correlated with the preset electronic control pressure cutoff value.

[0010] In some embodiments, the functional relationship is as follows: Where I is the motor displacement control current value, F is the tension of the lifting rope, and D is the torque of the lifting rope. n P is the winding diameter. cut The preset electronically controlled pressure cutoff value is given by k, which is a system parameter, and I is the value of k. o To correct the parameters.

[0011] In some embodiments, the winding diameter of the outermost lifting rope is determined based on the diameter of the winch drum, the diameter of the lifting rope, and the number of layers of the lifting rope currently wound.

[0012] In some embodiments, determining the motor displacement control current value corresponding to any one hoisting motor includes: acquiring a displacement signal of the operating component; acquiring a pressure value at the inlet of each motor based on the displacement signal while outputting a gradually increasing current signal to each hoisting motor; and determining the motor displacement control current value corresponding to any one hoisting motor based on the relationship between the pressure value and a preset electronic control pressure cutoff value.

[0013] In some embodiments, determining the motor displacement control current value corresponding to any hoist motor includes: when any pressure value reaches a preset electronic control pressure cutoff value, using the current current value as the motor displacement control current value; and when the pressure value at each motor inlet is less than the preset electronic control pressure cutoff value, the maximum value of the motor displacement control current value is the current value corresponding to the minimum motor displacement.

[0014] In some embodiments, determining the motor displacement control current value corresponding to any hoist motor further includes: when any pressure value reaches a first pressure value and continues for a first predetermined time, the motor displacement control current value gradually decreases from the current current value in predetermined steps until the pressure value at each motor inlet is less than or equal to a second pressure value, then the current current value is maintained, wherein the first pressure value is greater than a preset electrical control pressure cut-off value, and the second pressure value is less than the preset electrical control pressure cut-off value.

[0015] In some embodiments, determining the motor displacement control current value corresponding to any hoist motor further includes: during the process of the operating component increasing displacement, if the pressure value at each motor inlet is less than or equal to the second pressure value, and after a second predetermined time, the motor displacement control current value gradually increases from the current value with a predetermined step size; and when any pressure value reaches a preset electronic control pressure cutoff value, the current current value is maintained, and if the pressure value at each motor inlet is less than the preset electronic control pressure cutoff value, the motor displacement control current value gradually increases to the current value corresponding to the current displacement of the control component.

[0016] In some embodiments, determining the motor displacement control current value corresponding to any hoist motor further includes: during the process of the operating component decreasing displacement, if the current current value is less than the current value maintained when the pressure value at each motor inlet is less than or equal to the second pressure value, then the motor displacement control current value is the current value corresponding to the current displacement of the operating component.

[0017] In some embodiments, when the hoisting load is under heavy load, the motor displacement control current value corresponding to any hoisting motor is the current value corresponding to the maximum motor displacement.

[0018] In some embodiments, when the hoisting load is unloaded, the motor displacement control current value corresponding to any hoisting motor is the current value corresponding to the minimum motor displacement.

[0019] According to another aspect of this disclosure, a hoisting synchronization control device is also proposed, comprising: a current determination module configured to determine, for multi-hoisting operating conditions, a motor displacement control current value corresponding to any hoisting motor based on a preset electrical control pressure cutoff value when the hoisting load is between no load and heavy load, wherein the preset electrical control pressure cutoff value is less than the mechanical pressure cutoff value; and a synchronization control module configured to output a motor displacement control current value to each hoisting motor to control each hoisting motor to have the same displacement.

[0020] In some embodiments, the current determination module is configured to determine the winding diameter of the outermost lifting rope of any winch at the current moment, and calculate the motor displacement control current value corresponding to any winch motor based on the tension of the lifting rope, the winding diameter, and the preset electronic control pressure cut-off value of each winch.

[0021] In some embodiments, the current determination module is configured to acquire the displacement signal of the operating component, acquire the pressure value at the inlet of each motor based on the displacement signal while outputting a gradually increasing current signal to each hoisting motor, and determine the motor displacement control current value corresponding to any hoisting motor based on the relationship between the pressure value and the preset electronic control pressure cut-off value.

[0022] According to another aspect of this disclosure, a hoisting synchronization control device is also proposed, comprising: a memory; and a processor coupled to the memory, the processor being configured to execute the hoisting synchronization control method as described above based on instructions stored in the memory.

[0023] According to another aspect of this disclosure, a crane is also provided, comprising: the aforementioned hoisting synchronization control device.

[0024] According to another aspect of this disclosure, a non-transient computer-readable storage medium is also proposed, on which computer program instructions are stored, which, when executed by a processor, implement the hoisting synchronization control method as described above.

[0025] In this embodiment, a preset electronically controlled pressure cutoff value is used to calculate the motor displacement control current value corresponding to any hoisting motor, and the motor displacement control current value is output to each hoisting motor, so that each hoisting motor has the same displacement. This reduces the requirements for motor manufacturing consistency, improves adaptability, and avoids the problem of asynchronous operation of dual hoists caused by the motor's own pressure cutoff function. In addition, since the preset electronically controlled pressure cutoff value ensures that the motor operates at the minimum working displacement under the current load, the motor speed can be increased when dual or multiple hoists are synchronized, thereby improving system efficiency.

[0026] Other features and advantages of this disclosure will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0027] The accompanying drawings, which form part of this specification, illustrate embodiments of this disclosure and, together with the specification, serve to explain the principles of this disclosure.

[0028] This disclosure will become clearer with reference to the accompanying drawings and the following detailed description, wherein:

[0029] Figure 1 This is a flowchart illustrating some embodiments of the hoist synchronization control method disclosed herein;

[0030] Figure 2 The following are schematic flowcharts illustrating other embodiments of the hoist synchronization control method disclosed herein;

[0031] Figure 3 This is a schematic diagram of some embodiments of the relationship between current and displacement of an electro-proportional variable motor disclosed herein;

[0032] Figure 4 Schematic diagrams of other embodiments of the relationship between current and displacement of an electro-proportional variable motor disclosed herein;

[0033] Figure 5 The following are schematic flowcharts illustrating other embodiments of the hoist synchronization control method disclosed herein;

[0034] Figure 6 These are schematic diagrams illustrating the structure of some embodiments of the hoist synchronization control device disclosed herein; and

[0035] Figure 7 This is a schematic diagram of the structure of some other embodiments of the hoist synchronization control device disclosed herein. Detailed Implementation

[0036] Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present disclosure.

[0037] At the same time, it should be understood that, for ease of description, the dimensions of the various parts shown in the accompanying drawings are not drawn according to actual scale.

[0038] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this disclosure or its application or use.

[0039] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0040] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0041] 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 discussed further in subsequent figures.

[0042] To make the objectives, technical solutions, and advantages of this disclosure clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0043] Currently, one solution to the asynchronous problem of dual winches caused by the motor's own pressure cut-off function is to replace the motor or the motor's variable displacement mechanism, ensuring synchronization through component consistency. Another solution is to design an "electrically controlled pressure cut-off" function on the aforementioned motor with its built-in pressure cut-off function ("mechanical pressure cut-off"). Based on known parameters, combined with experience or repeated experiments, the electrically controlled pressure cut-off value is set to be lower than the motor's factory-set "mechanical pressure cut-off" value. When the load pressure is lower than the electrically controlled cut-off pressure value, the motor displacement is controlled by the handle's electronic control signal to achieve high speed; when the load pressure is higher than the electrically controlled cut-off pressure, the motor is directly controlled to its maximum displacement, avoiding the motor's own pressure cut-off and forcing the two motors to have equal displacement, thus ensuring synchronization.

[0044] The first solution, relying solely on component replacement, involves significant movement, high costs, and contamination of the main hydraulic system. The second solution, when the load pressure is below the electrically controlled cut-off pressure, only controls the motor displacement via the handle's electrical signal. Furthermore, even under light to medium loads, when the system pressure reaches the electrically controlled cut-off pressure, the motor consistently operates at maximum displacement. While this ensures synchronization, it sacrifices lifting speed, resulting in low lifting efficiency under light to medium loads.

[0045] This disclosure solves the asynchrony problem caused by inconsistent displacement of dual or multiple winches in single-hook dual-winch and multi-winch operating conditions due to differences in motor manufacturing precision and debugging parameters, which is addressed by the built-in pressure cutoff mechanism, thus reducing the impact on component consistency. Furthermore, it can increase the motor speed during synchronous lifting / lowering of dual or multiple winches under light and medium load conditions, thereby improving system efficiency.

[0046] Figure 1 This is a flowchart illustrating some embodiments of the hoist synchronization control method disclosed herein.

[0047] In step 110, for multi-winch working conditions, when the winch load is between no load and heavy load, the motor displacement control current value corresponding to any winch motor is determined based on the preset electronic control pressure cut-off value, wherein the preset electronic control pressure cut-off value is less than the mechanical pressure cut-off value.

[0048] In some embodiments, if the crane includes two winches, the two winches share the load equally, thereby enabling the determination of whether the winches are under heavy load, no load, or a combination of both. Heavy load and light load are determined by whether the operating condition reaches a preset electronically controlled pressure cutoff value.

[0049] In some embodiments, an electronically controlled pressure cutoff value P, slightly smaller than the motor's own pressure cutoff value, is preset. cut This value serves as the control benchmark, ensuring that the motor inlet pressure is less than the preset pressure cut-off value, and controlling the motor displacement to the minimum displacement that can overcome the load.

[0050] In some embodiments, the motor displacement control current corresponding to the hoisting motor is calculated by using a preset electronic control pressure cutoff value and either an active displacement control method or a passive displacement control method.

[0051] For example, by using the electronically controlled pressure cut-off value, the functional relationship between the motor displacement control current and torque under different load conditions can be calculated, and the maximum output current of the handle can be actively limited, that is, the minimum displacement of the motor that can overcome the load can be controlled.

[0052] For example, based on the relationship between the detected pressure at the inlet of the main and auxiliary hoists and the electrical control pressure cutoff value, the motor displacement control current value is passively limited.

[0053] In step 120, a motor displacement control current value is output to each winch motor to control each winch motor to have the same displacement.

[0054] In some embodiments, if the crane includes two winches, the motor displacement control current value is output to the motor of each winch, thereby enabling each motor to have the same displacement, so that the motor operates at the minimum working displacement under a preset pressure value, thereby achieving synchronous control of multiple winches.

[0055] In the above embodiments, the motor displacement control current value corresponding to any hoisting motor is calculated by using a preset electronic control pressure cutoff value, and the motor displacement control current value is output to each hoisting motor, so that each hoisting motor has the same displacement, realizing multi-hoisting synchronous control. In addition, since the preset electronic control pressure cutoff value ensures that the motor works at the minimum working displacement under the current load, the motor speed can be improved when two or more hoists are synchronized, thus improving the system efficiency.

[0056] Figure 2This is a flowchart illustrating some other embodiments of the hoist synchronization control method disclosed herein.

[0057] In step 210, when the hoist load is between no load and heavy load, the winding diameter of the outermost hoisting rope of any hoist at the current moment is determined.

[0058] In some embodiments, the winding diameter of the outermost lifting rope is determined based on the diameter of the winch drum, the diameter of the lifting rope, and the current number of layers of the lifting rope wound. For example, if the lifting rope is a wire rope, according to formula D... n =D + (2n-1) × d, calculate the winding diameter D of the outermost wire rope at the current moment. n Where D is the drum diameter in meters (m); d is the wire rope diameter in meters (m); and n is the number of layers of the wire rope, which can be determined in advance by calibrating the winch encoder to know which layer the wire rope is currently in.

[0059] In step 220, the motor displacement control current value corresponding to any hoist motor is calculated based on the tension of the hoisting rope, the winding diameter, and the preset electrical control pressure cut-off value of each hoist.

[0060] In some embodiments, the motor displacement control current value corresponding to any hoist motor is calculated based on the functional relationship between the motor displacement control current value, the torque of any hoist, and the preset electronic control pressure cut-off value, wherein the torque is the product of the tension of the hoisting rope and the winding diameter.

[0061] Torque is the cause of pressure changes. Torque causes the motor pressure to approach the motor pressure cutoff, resulting in displacement changes and thus speed instability. The motor displacement and control current are controlled by using the actual load as a reference. This is not a direct factor. If the influence of the number of wire rope layers is ignored, it will cause a discrepancy with the actual situation.

[0062] In some embodiments, the motor displacement control current value is linearly negatively related to the torque of any winch and positively correlated with the preset electronic control pressure cutoff value.

[0063] For example, the functional relationship is Where I is the motor displacement control current value, F is the tension of the lifting rope, and D is the torque of the lifting rope. n P is the winding diameter. cut The preset electronically controlled pressure cutoff value is given by k, which is a system parameter, and I is the value of k. o To correct the parameters.

[0064] The functional relationship between the motor displacement control current value, the winch torque, and the preset electronic control pressure cutoff value will be derived below.

[0065] The torque applied to the motor by the load is calculated using formula (1).

[0066]

[0067] Where T is the output torque of the motor at a single winch, in Nm; F is the tension of a single rope, in N, which is obtained through a tension sensor; i is the reduction ratio of the reducer; η h For pulley efficiency; η j The mechanical efficiency of the speed reducer; η m D represents the mechanical efficiency of the motor. n The current winding diameter of the outermost wire rope is obtained through a calculation formula.

[0068] The relationship between motor torque, motor inlet pressure, and motor displacement is shown in formula (2).

[0069]

[0070] Where T is the output torque of the motor at a single winch, in Nm; P is the motor inlet pressure, in bar; Vg is the motor displacement, in ml / r; η m This refers to the mechanical efficiency of the motor.

[0071] Formula (3) is obtained by using formulas (1) and (2).

[0072]

[0073] make Where k is a constant, the relationship between load and motor displacement can be calculated as shown in formula (4).

[0074]

[0075] In some embodiments, the relationship between the current and displacement of an electro-proportional variable motor is as follows: Figure 3 As shown, taking Rexroth's electric motor as an example, when the current is 600mA, the motor displacement is zero and the minimum; when the current is 200mA, it is 100% and the motor is at its maximum displacement. The formula for the relationship between current and displacement of an electric proportional variable motor is formula (5).

[0076]

[0077] Wherein, I represents current. Those skilled in the art will understand that this application can also be applied to other brands of motors using hydraulic or other control methods.

[0078] Formula (6) is obtained by using formulas (4) and (5).

[0079]

[0080] In this disclosure, P is taken as the electronically controlled pressure cutoff value P. cut In addition, in order to make the control more accurate and find a reasonable control range, a current correction value is added to the formula (6), as shown in formula (7). That is, the intercept of the function on the vertical axis is changed, the position of the function curve is changed, and thus the adjustment range is changed.

[0081]

[0082] In some embodiments, to avoid motor overspeeding issues caused by excessively small motor displacement, a minimum motor displacement is typically calculated and limited by mechanical switches to ensure safety. For example, in a dual-winch hoisting system, a Rexroth 200cc / r motor is used, with a minimum displacement set at 70cc / r. Figure 3 As shown, the motor displacement control current range controlled by the handle is 200-460mA. According to formula (7), there is no current change outside the function, which can cover the motor displacement control current range. The torque before and after correction are shown in the curves of the relationship between the torque and the motor displacement control current function. Figure 4 As shown.

[0083] For different loads, the maximum current output of the handle of each layer can be directly limited by the program. That is, the maximum current when the handle is at its maximum opening is the value calculated according to formula (7) in the input program.

[0084] In step 230, a motor displacement control current value is output to each winch motor to control each winch motor to have the same displacement.

[0085] In the above embodiments, based on the winch load, winding diameter, and preset electronic control pressure cutoff value, the motor displacement control current value corresponding to any winch motor under different working conditions is calculated, and the maximum output current of the handle is actively limited. This can eliminate control step intervals and eliminate control abrupt changes. Furthermore, since each winch motor has the same displacement, multi-winch synchronous control can be achieved.

[0086] Figure 5 This is a flowchart illustrating some other embodiments of the hoist synchronization control method disclosed herein.

[0087] In step 510, when the hoist load is between no load and heavy load, the displacement signal of the operating component is acquired.

[0088] In some embodiments, the operating component is, for example, an operating handle.

[0089] In some embodiments, taking a Rexroth 200cc / r displacement motor selected in a dual-winch hoisting system, with a minimum displacement setting of 70cc / r as an example, the motor displacement control current range controlled by the handle is 200-460mA, the factory-set value for motor self-pressure cutoff is 200bar, and the preset electronic control pressure cutoff value P cut The pressure is 185 bar. The operating handle is gradually pushed / pulled from the middle position to the maximum opening.

[0090] In step 520, based on the displacement signal, the pressure value at the inlet of each motor is obtained while outputting a gradually increasing current signal to each hoisting motor.

[0091] In some embodiments, as the operating handle is gradually pushed / pulled from the middle position to the maximum opening, the current of the motor displacement control proportional valve is supplied starting from 200mA. The current gradually and evenly increases with the handle. During this process, the pressure value of each motor inlet is obtained through the pressure sensor.

[0092] In step 530, the motor displacement control current value corresponding to any hoist motor is determined based on the relationship between the pressure value and the preset electronic control pressure cut-off value.

[0093] In some embodiments, when any pressure value reaches a preset electrically controlled pressure cutoff value, the current current value is used as the motor displacement control current value. When the pressure value at each motor inlet is less than the preset electrically controlled pressure cutoff value, the maximum value of the motor displacement control current value is the current value corresponding to the minimum motor displacement.

[0094] For example, if either of the two pressure sensors at the inlet of the main and auxiliary hoist motors detects a pressure reaching P, then... cut =185 bar, the current supplied to the motor will remain at the current value and will not continue to increase. Otherwise, as the handle opening is pulled to the maximum, the maximum current supplied to the motor will be 460mA, which corresponds to the minimum displacement of the motor 70ml.

[0095] In some embodiments, when any pressure value reaches the first pressure value and remains so for a first predetermined time, the motor displacement control current value gradually decreases from the current value in predetermined steps until the pressure value at each motor inlet is less than or equal to the second pressure value, then the current current value is maintained, wherein the first pressure value is greater than a preset electronic control pressure cut-off value and the second pressure value is less than the preset electronic control pressure cut-off value.

[0096] For example, if the two pressure sensors at the inlet of the main and auxiliary hoist motors detect that one of the pressure values ​​reaches P′ = P, then... cutIf +ΔP = 195 bar and this pressure value remains above 1.5 seconds, the current of the main and auxiliary winch motors will decrease uniformly from the current value at a rate of ΔI = 20 mA per cycle until the pressure values ​​detected by both motor pressure sensors are less than or equal to 150 bar. Then, the current current value will be maintained. ΔP and ΔI should be adjusted according to the actual situation to achieve the best results.

[0097] In some embodiments, during the process of increasing displacement of the operating component, if the pressure value at each motor inlet is less than or equal to the second pressure value, and after a second predetermined time, the motor displacement control current value gradually increases from the current value with a predetermined step size; and if any pressure value reaches a preset electronic control pressure cutoff value, the current current value is maintained, and if the pressure value at each motor inlet is less than the preset electronic control pressure cutoff value, the motor displacement control current value gradually increases to the current value corresponding to the current displacement of the control component.

[0098] For example, if both motor pressure sensors detect pressure values ​​less than or equal to 150 bar, and maintain the current current value, a predetermined delay is imposed, e.g., a delay of Δt1 = 1 second. If the handle remains in its current non-neutral position or continues to be operated towards its maximum opening direction, the current values ​​of the two motors increase at a rate of 20 mA per cycle to the current value corresponding to the current handle position. During this process, if either pressure sensor detects a pressure reaching p... cut =185 bar, the current remains at the current value under the current pressure and will not continue to rise. Δt1 should be adjusted according to the actual situation to obtain the best results.

[0099] In some embodiments, when the operating component is in the process of decreasing displacement, if the current current value is less than the current value maintained when the pressure value at each motor inlet is less than or equal to the second pressure value, then the motor displacement control current value is the current value corresponding to the current displacement of the operating component.

[0100] In step 540, a motor displacement control current value is output to each winch motor to control each winch motor to have the same displacement.

[0101] In the above embodiments, the system pressure, as a direct variable, is used as the control object. The motor displacement is automatically controlled by the program without any conversion or consideration of the current load and working conditions such as the wire layer. The motor displacement control current can cover the entire range. In other words, through passive displacement control, hoist synchronization can be achieved simply and efficiently.

[0102] In some other embodiments of this disclosure, when the hoisting load is under heavy load, the motor displacement control current value corresponding to any hoisting motor is the current value corresponding to the maximum motor displacement.

[0103] For dual winches, if the winch load is under heavy load, even if the motor is at its maximum displacement, it will require a pressure higher than the pressure cut-off value to overcome the load. Therefore, there is no need for control at this time. Both motors are controlled to their maximum displacement, which can increase the lifting capacity and ensure better synchronization.

[0104] In some other embodiments of this disclosure, when the hoisting load is unloaded, the motor displacement control current value corresponding to any hoisting motor is the current value corresponding to the minimum motor displacement.

[0105] For dual winches, if the winch load is in an empty or light load condition, even if the motor is working at its minimum displacement, the pressure is lower than the preset electronically controlled pressure cutoff value. At this time, no control is needed, and the displacement of both motors is controlled to the minimum displacement, thus ensuring good efficiency and synchronization.

[0106] Figure 6 The diagram below shows some embodiments of the hoisting synchronization control device disclosed herein, which includes a current determination module 610 and a synchronization control module 620.

[0107] The current determination module 610 is configured to determine the motor displacement control current value corresponding to any hoist motor based on a preset electronic control pressure cut-off value for multi-hoisting working conditions when the hoisting load is between no load and heavy load.

[0108] In some embodiments, the current determination module 610 is configured to determine the winding diameter of the outermost lifting rope of any winch at the current moment, and calculate the motor displacement control current value corresponding to any winch motor based on the tension of the lifting rope of each winch, the winding diameter, and a preset electronic control pressure cut-off value. The winding diameter of the outermost lifting rope is determined based on the drum diameter of the winch, the diameter of the lifting rope, and the current number of layers of the lifting rope wound.

[0109] The current determination module 610 calculates the motor displacement control current value corresponding to any hoist motor based on the functional relationship between the motor displacement control current value, the torque of any hoist, and the preset electronic control pressure cut-off value. Here, the torque is the product of the tension of the hoisting rope and the winding diameter.

[0110] The motor displacement control current value has a linear negative function relationship with the torque of any winch, and a positive correlation with the preset electronic control pressure cut-off value.

[0111] For example, the functional relationship is Where I is the motor displacement control current value, F is the tension of the lifting rope, and D is the torque of the lifting rope. n P is the winding diameter. cut The preset electronically controlled pressure cutoff value is given by k, which is a system parameter, and I is the value of k. oTo correct the parameters.

[0112] In some embodiments, the current determination module 610 is configured to acquire the displacement signal of the operating component, acquire the pressure value at the inlet of each motor based on the displacement signal while outputting a gradually increasing current signal to each hoisting motor, and determine the motor displacement control current value corresponding to any hoisting motor based on the relationship between the pressure value and the preset electronic control pressure cut-off value.

[0113] For example, the current determination module 610 is configured to use the current value as the motor displacement control current value when any pressure value reaches the preset electronic control pressure cut-off value; and when the pressure value at each motor inlet is less than the preset electronic control pressure cut-off value, the maximum value of the motor displacement control current value is the current value corresponding to the minimum motor displacement.

[0114] For example, the current determination module 610 is configured such that when any pressure value reaches a first pressure value and continues for a first predetermined time, the motor displacement control current value gradually decreases from the current current value in predetermined steps until the pressure value at each motor inlet is less than or equal to a second pressure value, then the current current value is maintained, wherein the first pressure value is greater than a preset electronic control pressure cut-off value and the second pressure value is less than the preset electronic control pressure cut-off value.

[0115] For example, the current determination module 610 is configured to, during the process of increasing displacement of the operating component, if the pressure value at each motor inlet is less than or equal to a second pressure value and after a second predetermined time, gradually increase the motor displacement control current value from the current value in predetermined steps; and if any pressure value reaches a preset electronic control pressure cutoff value, maintain the current current value, and if the pressure value at each motor inlet is less than the preset electronic control pressure cutoff value, gradually increase the motor displacement control current value to the current value corresponding to the current displacement of the control component.

[0116] For example, the current determination module 610 is configured such that, during the process of the operating component undergoing a displacement reduction, if the current current value is less than the current value maintained when the pressure value at each motor inlet is less than or equal to the second pressure value, then the motor displacement control current value is the current value corresponding to the current displacement of the operating component.

[0117] The synchronization control module 620 is configured to output a motor displacement control current value to each winch motor to control each winch motor to have the same displacement.

[0118] In the above embodiments, the motor variable current value is automatically controlled to ensure that the detected motor pressure within the motor variable range does not exceed the preset electronic control pressure cut-off value. The use of the electronic control pressure cut-off function ensures the consistency of the two motor variables, ensures the same motor displacement, and further ensures that the motor works at the minimum working displacement under the current load. This improves the motor speed during dual winch synchronization under light and medium load conditions and improves system efficiency.

[0119] In some other embodiments of this disclosure, the current determination module 610 is further configured such that, when the hoisting load is under heavy load, the motor displacement control current value corresponding to any hoisting motor is the current value corresponding to the maximum motor displacement.

[0120] In some other embodiments of this disclosure, the current determination module 610 is further configured such that, when the hoisting load is unloaded, the motor displacement control current value corresponding to any hoisting motor is the current value corresponding to the minimum motor displacement.

[0121] Figure 7 The diagram below illustrates the structure of another embodiment of the hoist synchronization control device 700 disclosed herein. The hoist synchronization control device 700 includes a memory 710 and a processor 720. The memory 710 can be a disk, flash memory, or any other non-volatile storage medium. The memory is used to store instructions in the corresponding embodiments described above. The processor 720 is coupled to the memory 710 and can be implemented as one or more integrated circuits, such as a microprocessor or microcontroller. The processor 720 is used to execute the instructions stored in the memory.

[0122] In some embodiments, the processor 720 is coupled to the memory 710 via a BUS bus 730. The hoist synchronization control device 700 can also be connected to an external storage system 750 via a storage interface 740 to access external data, and can also be connected to a network or another computer system (not shown) via a network interface 760. Further details are omitted here.

[0123] In this embodiment, by storing data instructions in a memory and then processing the instructions by a processor, the problem of asynchronous operation of the two winches when the motor is near its own pressure cut-off value ("mechanical pressure cut-off") can be avoided, while improving efficiency under light and medium load conditions.

[0124] In other embodiments of this disclosure, a crane is also protected, which includes the hoisting synchronization control device described above. This hoisting synchronization control device can solve the problem of asynchrony caused by inconsistent displacement of multiple hoisting motors. In addition, this disclosure has low requirements for the consistency of motor manufacturing and has good adaptability, avoiding the problem of asynchrony between the two hoists caused by the motor's own pressure cut-off function.

[0125] In other embodiments, a computer-readable storage medium stores computer program instructions that, when executed by a processor, implement the steps of the methods in the corresponding embodiments described above. Those skilled in the art will understand that embodiments of this disclosure can be provided as methods, apparatus, or computer program products. Therefore, this disclosure can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this disclosure can take the form of a computer program product embodied on one or more computer-usable non-transitory storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0126] This disclosure is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this disclosure. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create a machine for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0127] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0128] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0129] This concludes the detailed description of the present disclosure. To avoid obscuring the concept of the disclosure, some details known in the art have not been described. Those skilled in the art will fully understand how to implement the technical solutions disclosed herein based on the above description.

[0130] While specific embodiments of this disclosure have been described in detail by way of example, those skilled in the art should understand that the examples are for illustrative purposes only and not intended to limit the scope of this disclosure. Those skilled in the art should understand that modifications can be made to the above embodiments without departing from the scope and spirit of this disclosure. The scope of this disclosure is defined by the appended claims.

Claims

1. A hoist synchronization control method, comprising: For multi-winch working conditions, when the winch load is between no load and heavy load, the displacement signal of the operating component is acquired; Based on the displacement signal, the pressure value at the inlet of each motor is obtained during the process of outputting a gradually increasing current signal to each hoisting motor. Based on the relationship between the pressure value and the preset electronic pressure cut-off value, the motor displacement control current value corresponding to any hoist motor is determined, wherein the preset electronic pressure cut-off value is less than the mechanical pressure cut-off value; as well as The motor displacement control current value is output to each winch motor to control each winch motor to have the same displacement.

2. The hoist synchronization control method according to claim 1, wherein Determining the motor displacement control current value corresponding to any one of the hoisting motors includes: If any pressure value reaches the preset electronically controlled pressure cutoff value, the current current value will be used as the motor displacement control current value; and When the pressure value at each motor inlet is less than the preset electronic control pressure cut-off value, the maximum value of the motor displacement control current value is the current value corresponding to the minimum motor displacement.

3. The hoist synchronization control method according to claim 1, wherein Determining the motor displacement control current value corresponding to any one of the hoisting motors also includes: If any pressure value reaches the first pressure value and remains so for a first predetermined time, the motor displacement control current value gradually decreases from the current current value in predetermined steps until the pressure value at each motor inlet is less than or equal to the second pressure value, then the current current value is maintained, wherein the first pressure value is greater than the preset electronic control pressure cutoff value, and the second pressure value is less than the preset electronic control pressure cutoff value.

4. The hoisting synchronization control method according to claim 3, wherein, Determining the motor displacement control current value corresponding to any one of the hoisting motors also includes: During the process of increasing displacement of the operating component, if the pressure value at each motor inlet is less than or equal to the second pressure value, and after a second predetermined time, the motor displacement control current value gradually increases from the current value in predetermined steps; and If any pressure value reaches the preset electronically controlled pressure cutoff value, the current current value is maintained. If the pressure value at each motor inlet is less than the preset electronically controlled pressure cutoff value, the motor displacement control current value is gradually increased to the current value corresponding to the current displacement of the control component.

5. The hoisting synchronization control method according to claim 3, wherein, Determining the motor displacement control current value corresponding to any one of the hoisting motors also includes: During the process of the operating component decreasing displacement, if the current value is less than the current value maintained when the pressure value at each motor inlet is less than or equal to the second pressure value, then the motor displacement control current value is the current value corresponding to the current displacement of the operating component.

6. The hoisting synchronization control method according to any one of claims 1 to 5 further includes: When the hoisting load is under the heavy load condition, the motor displacement control current value corresponding to any one of the hoisting motors is the current value corresponding to the maximum displacement of the motor.

7. The hoisting synchronization control method according to any one of claims 1 to 5, further comprising: When the hoisting load is under no-load conditions, the motor displacement control current value corresponding to any hoisting motor is the current value corresponding to the minimum motor displacement.

8. A hoist synchronization control device, comprising: A current determination module is configured to, for multi-hoisting operation conditions, acquire displacement signals of operating components when the hoisting load is between no-load and heavy-load conditions. Based on these displacement signals, and while outputting gradually increasing current signals to each hoisting motor, acquire the pressure value at the inlet of each motor. Based on the relationship between these pressure values ​​and a preset electronically controlled pressure cutoff value, determine the motor displacement control current value corresponding to any hoisting motor, wherein the preset electronically controlled pressure cutoff value is less than the mechanical pressure cutoff value. The synchronization control module is configured to output the motor displacement control current value to each winch motor to control each winch motor to have the same displacement.

9. A hoist synchronization control device, comprising: Memory; as well as A processor coupled to the memory, the processor being configured to execute the hoisting synchronization control method as described in any one of claims 1 to 7 based on instructions stored in the memory.

10. A crane, comprising: The hoisting synchronization control device as described in claim 8 or 9.

11. A non-transitory computer-readable storage medium having stored thereon computer program instructions that, when executed by a processor, implement the hoisting synchronization control method as described in any one of claims 1 to 7.

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