WO2013086889A1 - Method, device and system for controlling crane rotation, and crane - Google Patents

Abstract

Disclosed are a method, a device and a system for controlling the rotation of a crane, and a crane. The method comprises: obtaining the rotating linear velocity of the pendant ballast according to the rotating linear velocity of the rotating mechanism of the present crane, the length of the pendulum formed by the pendant ballast and the pendant cord, and a preset included angle formed by the pendant cord and the vertical direction based on the present conditions of the crane; reducing the rotational speed of the crane when the differential between the rotating linear velocity of the rotating mechanism and the rotating linear velocity of the pendant ballast is greater than a first preset value. The method aids in reducing the impact from the ballast and the tangential deflection angle of the ballast and the impulse load on the head of the boom while meeting the stability, structural integrity and rigidity conditions of the vehicle, such that operational safety is ensured.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to the field of construction machinery control technology, and in particular, to a method, a device and a system for crane swing control, and a crane. BACKGROUND OF THE INVENTION Cranes are a common construction machine. For various cranes, there are usually legs, swivels, and booms. The boom head can be connected to the weight by wire ropes for lifting work. As shown in Fig. 1, Fig. 1 is a schematic view of a hoisting and swinging structure of a crane according to the prior art. The leg 11, the swivel platform 12, the boom 13, the boom head 14, the sling 15 connected between the boom head and the weight, and the sling 16 are shown in Fig. 1 . During the turning process, the slewing platform rotates about a straight line L which is perpendicular to the plane of revolution and passes through the center of revolution 0 of the slewing platform. In the related art, in order to ensure smooth operation, the swing of the crane is usually controlled based on the swing speed of the boom. In the process of realizing the present invention, the inventors have found that the control effect on the swing of the crane in the related art is not good in the case of the flexible connection of the hoisting weight. Referring to Figure 1, the boom head and the hoisting weight are rigid bodies, and the connection between them is a wire rope, which can be called a flexible connection. In the flexible connection state, since the arm running speed VI and the weight operating speed V2 are not the same at the start, stop and constant speed of the swing, the normal and tangential deflection of the heavy object is caused, resulting in the entire vehicle arm. The instability of the rack system or even the break or rollover. For the problem of poor control of the swing control of a crane for flexibly connecting a hoisting weight in the related art, an effective solution has not yet been proposed. SUMMARY OF THE INVENTION A primary object of the present invention is to provide a method, apparatus and system for crane slewing control and a crane to solve the problem of poor slewing control of a crane for flexibly connecting hoisting weights in the prior art. In order to achieve the above object, according to an aspect of the present invention, a method of crane swing control is provided. The method for controlling the swing of the crane provided by the invention comprises: according to the rotary line speed of the current swing mechanism of the crane, the length of the swing formed by the hoisting weight and the sling, and the preset sling and vertical direction for the current working condition of the crane Angle of rotation, the rotational speed of the hoisting weight is obtained; the rotational speed of the slewing mechanism exceeds In the case where the difference in the rotational linear velocity of the hoisting weight is greater than the first predetermined value, the rotational speed of the crane is lowered. Further, according to the rotational linear velocity of the slewing mechanism of the current crane, the preset angle of the sling with the vertical direction for the current working condition of the crane, and the length of the sling formed by the hoisting weight and the sling, The rotational linear velocity of the hoisting weight includes: determining Π according to the formula "= ^{aretan 2 _ X} ", where,

 4H

The included angle, Π represents the rotational linear velocity of the hoisting weight, represents the rotational linear velocity of the slewing mechanism, H represents the length of the pendulum, and Γ represents the period of the pendulum. Further, after the reducing the rotation speed of the crane, the method further comprises: increasing the rotational linear velocity of the swing mechanism of the crane if the difference is less than a second preset value. According to another aspect of the invention, an apparatus for crane swing control is provided. The device for slewing control of the crane provided by the invention comprises: a determining module, a slewing line speed according to a slewing mechanism of the current crane, a length of a sling formed by the hoisting weight and the sling, and a pre-set sling for the current working condition of the crane and An angle between the vertical direction, the rotational speed of the hoisting weight is obtained; the adjustment module, the difference between the rotational linear velocity of the slewing mechanism and the rotational linear velocity of the hoisting weight is greater than a first preset value In the case of the crane, the speed of rotation of the crane is lowered. Further, the determining module is further configured to: determine, according to the formula "= ^{aretan 2 _" x} , wherein

 4H

The angle is indicated, Π indicates the rotational linear velocity of the hoisting weight, indicates the rotational linear velocity of the slewing mechanism, H indicates the length of the pendulum, and Γ indicates the period of the pendulum. Further, the adjustment module is further configured to: when the difference is less than the second preset value, increase a rotational linear velocity of the swing mechanism of the crane. According to still another aspect of the present invention, a system for crane swing control is provided. The system of the crane swing control of the present invention comprises: an operating device for issuing an operation signal when subjected to external operation; and a control device for, during the survival of the operation signal, according to the rotational speed of the current swing mechanism of the crane, the hoisting weight The length of the pendulum formed by the object and the sling, and the angle between the sling which is preset for the current working condition of the crane and the vertical direction, the slewing linear velocity of the hoisting weight, and the slewing of the slewing mechanism In the case where the linear velocity exceeds the first predetermined value of the difference in the rotational linear velocity of the hoisting weight, the rotational speed of the crane is lowered. Further, the operating device is an operating handle of the crane; or the operating device is a pedal; or the operating device is a button. Further, the control device is further configured to increase a rotational linear velocity of the swing mechanism of the crane if the difference is less than a second preset value. According to still another aspect of the present invention, a crane is provided. The crane of the present invention has a device for flexibly connecting the hoisting weight, and also has a system for the slewing control of the crane of the present invention. According to the technical solution of the present invention, the rotational speed of the hoisting weight is calculated for the current working condition of the crane, and the difference between the rotational linear velocity of the hoisting weight and the rotational linear velocity of the slewing mechanism of the crane is controlled, so that the vehicle is satisfied Under the condition of stability, structural strength and rigidity, the rotation speed of the hoisting weight is controlled more accurately, which ensures the stability of the heavy object during the start, operation and stop of the swing, and the positioning, which greatly reduces the impact and weight of the heavy object. The tangential deflection angle and the impact load on the boom head achieve the control of the hoisting process to hoist the object. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings are intended to provide a further understanding of the invention In the drawings: Fig. 1 is a schematic view of a hoisting and swiveling structure of a crane according to the prior art. 2 is a schematic view of a method of swing control of a crane according to an embodiment of the present invention; FIG. 3 is a schematic view showing a running state of a swing plane according to an embodiment of the present invention; FIG. 4 is a diagram showing a rotational speed of a swinging mechanism of a crane according to an embodiment of the present invention. FIG. 5 is a schematic diagram of main components of a device for swing control of a crane according to an embodiment of the present invention; FIG. 6 is a schematic diagram of main components of a system for swing control of a crane according to an embodiment of the present invention; 7 is a schematic view of the operation handle stroke associated with the embodiment of the present invention; FIG. 8 is a schematic view showing the control current corresponding to the swing speed of the crane swing mechanism according to an embodiment of the present invention; 9 is a schematic diagram of a control mode according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS It should be noted that the embodiments in the present application and the features in the embodiments may be combined with each other without conflict. The invention will be described in detail below with reference to the drawings in conjunction with the embodiments. 2 is a schematic diagram of a method for swing control of a crane according to an embodiment of the present invention. As shown in FIG. 2, the method mainly includes the following steps: Step S21: According to the swing speed of the current swing mechanism of the crane, lifting weights and slings The length of the formed pendulum and the preset angle between the sling and the vertical direction for the current working condition of the crane, and the rotational linear velocity of the hoisting weight is obtained; Step S23: The rotational linear velocity of the slewing mechanism exceeds the hoisting weight In the case where the difference in the rotational linear velocity is greater than the first predetermined value, the rotational speed of the crane is lowered. The rotational linear velocity of the slewing mechanism of the crane can be determined in accordance with various existing methods. For example, according to the engine speed, according to the relationship between the engine speed and the maximum output flow of the swing pump, the maximum output speed of the swing motor, and the swing speed of the swing mechanism, it is also possible to directly detect the rotational speed of the gear in the swing mechanism to determine the swing of the swing mechanism. Line speed. The angle between the sling and the vertical direction for the current working condition of the crane can be preset. According to the current boom length and working range, the maximum lifting capacity and the minimum lifting weight can be calculated according to the structural stability formula. The angle between the two slings and the vertical direction is the maximum. Between the lifting weight and the minimum lifting weight, therefore, the angle between the sling and the vertical direction for the current working condition of the crane can be obtained by interpolation by the two angle values obtained by the above calculation. In addition, the above-mentioned angles set in advance can also directly adopt the values provided according to national standards.

In step S21, the rotation line of the hoisting object can be determined according to the formula = ^L^

 4H

speed. Wherein, the angle between the sling and the vertical direction of the current working condition of the crane is preset, Π indicates the rotational speed of the hoisting weight, indicating the degree of the slewing mechanism, and H indicates the sway formed by the hoisting weight and the sling The length, Γ represents the period of the pendulum, can be calculated using Γ = , where g is the acceleration of gravity.

among them. The length of the pendulum can be the length of the sling, or more precisely the distance between the head of the jib and the center of gravity of the hoisting weight. Depending on the control accuracy requirements. The formula for calculating the maximum output flow rate of the rotary pump can be ρ^ ζ ^^ · ; / , where is the displacement of the oil pump, which can be randomly changed according to the current, which is the engine speed. The calculation formula of the maximum output speed of the slewing motor is η _η = ^· η , where ^ is the displacement of the hydraulic motor, which can be randomly changed according to the current, and is the mechanical working efficiency. The calculation formula of the slewing mechanism's slewing speed is "= · is the slewing gear ratio, Ζ ₂ , and the number of gears is y Ζ _λ . The calculation can be as follows: ν2 = π · η · . Crane current operating radius

 30

The calculation method is R = J *c _0S +A^, where J is the length of the jib frame, which is the bulge angle of the jib, which is the deflection of the current jib and the jib frame in the direction of the jib of the boom. The calculation formula of the frame winding and the actual measured value of the field are corrected and calculated. It can be seen from the above calculation formula that the linear speed of the slewing mechanism or the acceleration and deceleration can be controlled by the hydraulically controlled variable pump and the electronically controlled variable motor in addition to the normal configuration of the system, and the linear speed of the slewing mechanism can also be By checking the rotational speed of the slewing mechanism, it is obtained through verification. In the above calculations, the units of each quantity may be in the international unit system or other unit systems. 3 is a schematic view showing an operational state of a rotary plane according to an embodiment of the present invention. Figure 3 shows the crane leg 31, the swivel body 32, the boom 33, the arm head 34, the sling 35, the sling 36, and the angle between the sling and the vertical direction (or the swing angle), The sling weight normal direction 37 and the tangential direction 38, as well as the hoisting weight 36 trajectory 39. The slewing linear velocity VI of the sling is in the tangential direction 38. The rotation speed of the crane slewing mechanism is controlled according to the above steps, and an example of the control effect obtained is shown in FIG. 4 is a schematic view of a rotary linear velocity and a sling weight linear velocity of a crane slewing mechanism according to an embodiment of the present invention. In the coordinate system shown in Fig. 4, the abscissa indicates time, the ordinate indicates speed, line 41 indicates the slewing linear speed of the crane, line 42 indicates the slewing speed of the hoisting weight, 43 indicates the slewing start phase, and 44 indicates the slewing smooth running phase. 45 denotes a swing stop phase, 46 denotes a phase in which the swing linear speed of the crane swing mechanism and the swing weight linear velocity are equal, and 47 denotes that the swing linear speed of the crane swing mechanism before the swing stop is equal to the swing weight speed of the hoisting weight Stage. TO is the slewing mechanism, that is, the starting time of the slewing rotation, and TO' is the starting time point of the sling rotation. Since the two are flexible connection methods, the time difference between TO and TO' exists objectively, so that there is a deflection angle α. According to the law of weight swing and the existing calculation method, the time difference between Τ0 and T0' can be approximated as 1/4 of the weight swing period T. At the same speed of the two, the deflection angle α is approximately zero. As shown in Fig. 4, after Τ2, the linear speed of the slewing mechanism of the crane is lowered, so that the slewing speed of the hoisting weight is close to the slewing speed of the slewing mechanism of the crane, and after Τ3, the slewing speed of the slewing mechanism of the crane can be increased. In actual operation, the rotational linear velocity of the slewing mechanism of the crane may be increased if the difference between the rotational linear velocity of the crane slewing mechanism and the rotational linear velocity of the hoisting weight is less than a preset value. Figure 5 is a schematic diagram of the main modules of the apparatus for swing control of a crane according to an embodiment of the present invention. As shown in FIG. 5, the apparatus 50 for swing control of a crane according to an embodiment of the present invention mainly includes: a determining module 51, which is configured to adjust a swing line speed of a swing mechanism of a current crane, a length of a swing formed by a hoisting weight and a sling, and Pre-set angle between the sling and the vertical direction for the current working condition of the crane, and the turning linear speed of the hoisting weight is obtained; the adjusting module 52 is used for the turning linear speed of the slewing mechanism beyond the turning speed of the hoisting object In the case where the difference is greater than the first preset value, the swing speed of the crane is lowered. The determining module 51 can also be used to: determine Π according to the formula "= ^{aretan 2 _" X} , where, "represent

 4H

The angle, Π represents the rotational linear velocity of the hoisting weight, represents the rotational linear velocity of the slewing mechanism, H represents the length of the sling formed by the sling and the sling, and Γ represents the period of the sway. The adjustment module 51 can also be configured to increase the rotational linear velocity of the slewing mechanism of the crane if the difference between the rotational linear velocity of the slewing mechanism and the rotational linear velocity of the hoisting weight is less than a second predetermined value. Figure 6 is a schematic illustration of the major components of a system for crane swing control in accordance with an embodiment of the present invention. The system of crane swing control 60 primarily includes an operating device 61 and a control device 62. Wherein the operating device 61 is configured to emit an operation signal when subjected to external operation; and the control device 62 is configured to, during the operation of the operation signal, the length of the swing formed by the hoisting weight and the sling according to the slewing mechanism of the current crane, And the preset angle between the sling and the vertical direction for the current working condition of the crane, the rotational speed of the hoisting weight is obtained, and the difference between the rotational linear velocity of the slewing mechanism and the rotational linear velocity of the hoisting object is greater than In the case of the first preset value, the speed of rotation of the crane is reduced. The handling device 61 can be an operating handle of a crane. It can also be a pedal or a button. In the prior art, the stroke of the operating handle determines the speed of rotation of the slewing mechanism of the crane. In this embodiment, regardless of the stroke size of the operating handle, the same operation command is regarded, and the rotation speed of the specific slewing mechanism of the crane is controlled. The device decides. Figure 7 is a schematic illustration of the stroke of the operating handle associated with an embodiment of the present invention. The handle 71, the handle travel path 72, the handle swing angle 73 and the handle stroke 74 are shown in FIG. The handle stroke is the length of the handle projected on a horizontal plane. Figure 8 is a schematic illustration of control current corresponding to the speed of rotation of a slewing mechanism of a crane in accordance with an embodiment of the present invention. The control current here is the current used to control the speed of the swing mechanism, applied in the manner of the prior art, for example on a rotary pump or a swing motor. Figure 8 shows a relationship curve 83 between the stroke of the handle and the current output by the handle, a relationship 82 between the stroke of the handle and the control current, and a relationship 83 between the rotational speeds of the slewing mechanism of the crane. It can be seen from Fig. 8 that the larger the stroke of the handle, the larger the output current can be, but the actual control current is determined by the control system and is not necessarily related to the stroke of the handle. The control system herein includes the system 60 of the present embodiment, which can operate in the manner of FIG. Figure 9 is a control in accordance with an embodiment of the present invention Schematic diagram of the way. The stroke of the handle actually gives a time period and the command requires actual control current during that time period, and the actual control current is not determined by the handle stroke. Under the control of the control system, the actual control current achieves the control effect as shown by curve 83. According to the technical solution of the present embodiment, by calculating the rotational linear velocity of the hoisting weight for the current working condition of the crane, and controlling the difference between the rotational linear velocity of the hoisting weight and the rotational linear velocity of the slewing mechanism of the crane, Under the condition of vehicle stability, structural strength and stiffness, the slewing speed of the hoisting object is controlled more accurately, which ensures the stability of the heavy object during the start, operation and stop of the slewing, positioning, and greatly reduces the impact of heavy objects. The tangential deflection angle of the weight and the impact load on the head of the boom realize the control of lifting the object in the lifting process. Obviously, those skilled in the art should understand that the above modules or steps of the present invention can be implemented by a general-purpose computing device, which can be concentrated on a single computing device or distributed over a network composed of multiple computing devices. Alternatively, they may be implemented by program code executable by the computing device, such that they may be stored in the storage device by the computing device, or they may be separately fabricated into individual integrated circuit modules, or they may be Multiple modules or steps are made into a single integrated circuit module. Thus, the invention is not limited to any specific combination of hardware and software. The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

Claims

Claim A method for controlling a swing of a crane, comprising:  According to the current rotational speed of the slewing mechanism of the crane, the length of the pendulum formed by the hoisting weight and the sling, and the angle between the sling and the vertical direction of the preset working condition of the crane, the hoisting weight is obtained. Rotating line speed  In the case where the difference in the rotational linear velocity of the slewing mechanism beyond the rotational linear velocity of the hoisting weight is greater than the first predetermined value, the rotational speed of the crane is lowered. 2. The method according to claim 1, wherein the slewing line speed according to the slewing mechanism of the current crane, the preset angle of the sling for the current working condition of the crane and the vertical direction, and the hoisting weight The length of the pendulum formed by the object and the sling, and the rotational speed of the hoisting weight is obtained, including:  Arctan ( 2- l)xJ . ,  Determine according to the formula " = ^ '- ~ Π  4H  Here, the angle is indicated, Π indicates the rotational linear velocity of the hoisting weight, indicates the rotational linear velocity of the slewing mechanism, H indicates the length of the pendulum, and Γ indicates the period of the pendulum. The method according to claim 1 or 2, wherein, after the reducing the rotation speed of the crane, the method further comprises: if the difference is less than a second preset value, increasing the The rotational linear velocity of the slewing mechanism of the crane. 4. A device for controlling the swing of a crane, comprising:  a determining module for determining the length of the slewing line of the hoisting mechanism of the current crane, the length of the sling formed by the hoisting weight and the sling, and the pre-set angle between the sling and the vertical direction for the current working condition of the crane The rotational speed of the hoisting weight;  And an adjustment module, configured to reduce a rotation speed of the crane when a difference in a rotational linear velocity of the swing mechanism exceeds a rotational speed of the hoisting weight is greater than a first preset value. 5. The apparatus according to claim 4, wherein the determining module is further configured to: arctan (2-l)xJ.  Determine according to the formula " = ^ '- ~ Π  4H Here, the angle is indicated, Π indicates the rotational linear velocity of the hoisting weight, indicates the rotational linear velocity of the slewing mechanism, H indicates the length of the pendulum, and Γ indicates the period of the pendulum. The apparatus according to claim 4 or 5, wherein the adjustment module is further configured to: increase a rotational linear velocity of the slewing mechanism of the crane if the difference is less than a second preset value . A system for crane swing control, comprising:  An operating device for issuing an operation signal when subjected to external operations;  a control device, for the duration of the operation signal, according to the slewing speed of the current slewing mechanism of the crane, the length of the sling formed by the hoisting weight and the sling, and the sling and the vertical setting for the current working condition of the crane An angle between the straight direction, the rotational speed of the hoisting weight is obtained, and the difference between the rotational linear velocity of the slewing mechanism and the rotational linear velocity of the hoisting weight is greater than a first preset value , reducing the speed of rotation of the crane. The system according to claim 7, wherein said operating device is an operating handle of said crane;  Or the operating device is a pedal;  Alternatively, the operating device is a button. The system according to claim 7 or 8, wherein the control means is further configured to increase a rotational linear velocity of the slewing mechanism of the crane if the difference is less than a second predetermined value. A crane having means for flexibly connecting a hoisting weight, characterized in that the crane further has the system of claim 7, 8, or 9.