WO2013075549A1

WO2013075549A1 - Method, apparatus, and system for measuring load of crane and crane

Info

Publication number: WO2013075549A1
Application number: PCT/CN2012/082129
Authority: WO
Inventors: 詹纯新; 刘权; 张建军; 钟清平; 彭亿祥
Original assignee: 中联重科股份有限公司; 湖南中联重科专用车有限责任公司
Priority date: 2011-11-22
Filing date: 2012-09-27
Publication date: 2013-05-30
Also published as: CN102431896A; CN102431896B

Abstract

A method, apparatus (20), and system for measuring a load of a crane, and the crane. The method comprises: step A: measuring the tensions of tension units evenly arranged on both sides of a boom, thereby acquiring two tension values; and step B: determining, on the basis of the two tension values, if a side load of the crane exceeds a predetermined range, then outputting the determination result. The method, apparatus (20), and system are capable of measuring conveniently and accurately the side load of the crane. Combined with the prior apparatus, only two tension measuring apparatus (31 and 32) are required to be added, increase in costs is minimal. In addition, when the two tension measuring apparatus (31 and 32) are added, convenience is allowed in determining if the load of the crane is overloaded, more direct and accurate when compared with the load measuring method for the prior torque limiter. The problem in measuring the side load of the crane is solved.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the field of construction machinery, and in particular, to a crane load detection method, apparatus and system, and a crane. BACKGROUND OF THE INVENTION Cranes are a common construction machine. In the related art, the overload protection safety device of the jib crane is mainly a torque limiter. In addition to being the core control unit of the crane, the torque limiter is one of the crane's main safety devices, which monitors the crane's real-time working conditions. The jib crane uses the hoisting torque characteristic to reflect the load state, and the torque value is determined by a number of parameters such as the lifting weight, the amplitude (the product of the arm length and the cosine of the jib angle), and the operating conditions. complex. The torque limiter is composed of a load detector, an arm length detector, an angle detector, a condition selector, and a microcomputer. When the crane enters the working state, the detection signals of the actual parameters are input into the computer. After calculation, amplification, and processing, the corresponding parameter values are displayed and compared with the pre-stored rated lifting torque values. When the actual value reaches 90% of the rated value, an early warning signal is issued, and when it is overloaded, an alarm signal is issued, and the crane stops moving in a dangerous direction (lifting, booming, lowering arm, turning). In the related art, when the main arm is a telescopic arm and the main variable amplitude is performed by the variable amplitude cylinder, the load detection of the torque limiter is to convert the hoisting load of the entire boom by detecting the pressure of the main variable cylinder, and the main variable oil cylinder It is a basic arm joint that connects one end of the turntable to the tail end of the main arm, so the detection of the pressure of the main variable cylinder is difficult to reflect the lateral load of the front part of the longer boom, especially the front section of the main telescopic arm. In this way, it is difficult for the torque limiter to detect the lateral load on the crane, and it is impossible to protect the boom system, especially the main telescopic arm, from the side bend caused by the lateral load overload, which may cause the risk of folding the arm. . In the related art, it is difficult to detect the lateral load on the crane, and an effective solution has not been proposed for this problem. SUMMARY OF THE INVENTION A primary object of the present invention is to provide a method, apparatus and system for crane load detection and a crane to solve the problem in the prior art that it is difficult to detect the lateral load on the crane. In order to achieve the above object, according to one aspect of the present invention, a method of crane load detection is provided. The method for detecting the load of the crane of the present invention comprises: Step A: detecting the tension of the tension unit symmetrically arranged on both sides of the boom, thereby obtaining two tension values; Step B: judging the side of the crane according to the two tension values Whether the load exceeds the preset range, and then outputs the judgment result. According to another aspect of the present invention, an apparatus for crane load detection is provided. The device for detecting the load of the crane of the present invention comprises: a receiving device, configured to receive a tensile force detection value of a tension unit symmetrically arranged on both sides of the lifting arm; a computing device, configured to determine a side load of the crane according to the two tensile values Whether the preset range is exceeded; the output device is configured to output the judgment result of the computing device. According to yet another aspect of the present invention, a system for crane load detection is provided. The crane load detecting system of the present invention comprises: two tensile force detecting devices for respectively detecting the tensile force of the tension unit symmetrically arranged on both sides of the lifting arm; the calculating device is connected with the tensile force detecting device, and is used according to the two The tension value of the tension unit determines whether the side load of the crane exceeds a preset range, or determines whether the crane is overloaded according to two of the tension values; and an output device connected to the computing device for outputting the calculation The result of the judgment by the device. According to still another aspect of the present invention, there is provided a crane including the system for crane load detection of the present invention. According to the technical solution of the present invention, the tension of the tension unit symmetrically arranged on both sides of the boom is detected, and the tension can directly reflect the size of the side load of the crane, so that the side load of the crane can be detected conveniently and accurately. In combination with the existing equipment, it is only necessary to add two tension detecting devices, and the cost increase is small. In addition, after adding the two tension detecting devices, it is convenient to determine whether the crane hoisting load is hoist overload, which is more direct and accurate than the existing torque limiter load detecting method. 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 diagram showing the basic steps of a method for detecting load of a crane according to an embodiment of the present invention; FIG. 2 is a schematic diagram of essential components of a device for detecting load of a crane according to an embodiment of the present invention; Schematic diagram of the basic components of a crane load detection system in accordance with an embodiment of the present invention; 4 is a schematic view of the basic structure of a crane 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. 1 is a schematic diagram of the basic steps of a method for detecting load of a crane according to an embodiment of the present invention. As shown in FIG. 1, the method mainly includes the following steps: Step S11: detecting a tensile force of a tension unit symmetrically arranged on both sides of the boom, Thereby obtaining two pull values. Step S13: determining whether the side load of the crane exceeds a preset range according to the obtained two pull values. Step S15: The judgment result in step S13 is output. The above steps are further explained below. When lifting the jib system, when the jib system is subjected to lateral wind load or lateral pulling of the wire rope component or subjected to sideways yaw and other lateral loads of the lifting object, the jib frame is especially the main The left and right deformation of the telescopic arm is inconsistent, so that the side bend occurs. At this time, the two tension values obtained in step S11 (hereinafter referred to as S1 and S2 respectively) are necessarily unequal, so it can be judged according to the obtained two pull values. Whether the side load of the crane is outside the preset range. After step S15, step S1 l may be returned after a preset delay (for example, 0.1S), and the steps in FIG. 1 are performed again, thereby continuously detecting the side load of the crane and continuously monitoring the working condition of the crane. effect. The tension unit symmetrically arranged on both sides of the lifting arm in step S11 may specifically be two super-lifting front-end pulling ropes or super-lifting and pulling-up steel cords of the crane. In the following, the step S 13 will be described in detail by taking the pulling force of the left and right super-lifting wire ropes of the left and right sides of the crane as an example.

S1 and S2 respectively represent the real-time tensile values of the left and right two pre-tensioned wire ropes symmetrically arranged on both sides of the boom under the current working conditions, and the ratio of the sum of S1 and S2 to the absolute value of the difference between S1 and S2 A, that is, A=(S1+S2)/|S1-S2|, obviously A is a real number greater than 1, which can be defined as the side load safety factor indicating the extent to which the boom is subjected to the side load. The larger the A value is, The closer the pulling force of the left and right front pull wire ropes, the smaller the side load that the jib boom system bears, and the safer the jib boom system. It can be seen that when S1=S2 (that is, the pulling force of the front and rear wire ropes is equal), it indicates that the jib frame system has almost no side load, and the safety factor A tends to infinity. According to whether the A value is greater than the first set value of the current working condition, it can be judged whether the side load of the crane is beyond the preset range under the current working condition. For example, the A value is sent to the torque limiter of the crane, and the torque limiter compares the A value with the preset side load safety factor rating B under the current operating condition, when A falls to 110% of the rated value B. The judgment result in step S13 is that the side load of the crane is close to the preset range, so that the warning signal can be issued in step S15; A continues to descend, and when A=B, the judgment result in step S13 is that the direction has been reached. The overload limit of the load, so that an alarm signal can be issued in step S15 and a signal for cutting off all dangerous actions can be issued at the same time; thereby stopping the crane in a dangerous direction (for example, lifting, booming, lowering arm, turning, etc.) ) Continue to move. The rated value of the tension value of the front pull wire rope can be pre-loaded in the torque limiter of the crane in advance, and the sum of the rated tensile force values of the tension unit symmetrically arranged on both sides of the crane under each working condition is represented by S. In the above method of the embodiment, after step S11, the magnitude relationship between S and S1+S2 can be directly compared, thereby making a direct and effective determination of whether the crane operation is overloaded and corresponding security protection. For example, when the value S1+S2 reaches 90% of the rated value S, an early warning signal is issued; when the value S1+S2 reaches 100% of the rated value S, that is, S1+S2=S, it is considered that the hoisting load has reached The rated load, an alarm signal is issued and the crane stops moving in the dangerous direction. 2 is a schematic diagram of essential components of a crane load detection apparatus in accordance with an embodiment of the present invention. As shown in FIG. 2, the crane load detecting device 20 mainly comprises a receiving device 21, a computing device 22 and an output device 23, wherein the receiving device 21 is configured to receive a tensile force detection value of a tension unit symmetrically arranged on both sides of the lifting arm; 22 is used to determine whether the side load of the crane exceeds a preset range according to the two pull values; the output device 23 is configured to output the judgment result of the computing device 22. The computing device 22 can also be used to determine whether (S1+S2)/|S1-S2| is greater than the first set value, and if so, confirm that the side load of the crane does not exceed the preset range, otherwise confirm that the side load of the crane exceeds the pre-load Set the scope. The computing device 22 can also be used to determine whether the crane is overloaded based on the magnitude relationship between S and S1+S2. The above S represents the sum of the rated tensile force values of the tension units symmetrically arranged on both sides of the boom, and S1 and S2 represent the above-described tensile force detection values. The output device 23 is used to output a result of the determination by the computing device 22 of whether the crane is overloaded. 3 is a schematic diagram of the basic components of a system for crane load detection in accordance with an embodiment of the present invention. As shown in FIG. 3, the crane load detection system of the embodiment of the present invention mainly includes: two tension detecting devices 31, 32, a computing device 33, and an output device 34. Wherein, two tension detecting devices 31, 32 are respectively used for detecting the tension of the tension unit symmetrically arranged on both sides of the boom; the calculating device 33 is respectively connected with the tension detecting devices 31, 32 for the tensile value according to the two tension units It is judged whether the side load of the crane exceeds the preset range, or whether the crane is overloaded according to the two pull values; the output device 34 is connected to the computing device 33 for outputting the result of the judgment by the calculating device 33. The computing device 33 and the output device 34 can be implemented using components of the associated functions of the crane torque limiter. The tension detecting devices 31, 32 may include storage elements for storing the tensile force detection values, such that the tension detecting devices 31, 32 may serve as "black boxes" for crane operating conditions, providing data support for analysis of crane operating accidents. 4 is a schematic view of the basic structure of a crane according to an embodiment of the present invention. The crane according to the embodiment of the present invention includes the crane load detecting system of the present invention, wherein, as shown in Fig. 4, tension detecting devices 411 and 412 are respectively connected to the two super-lifting front wire ropes 41, 42 of the crane. The tension detecting device is connected in series with the wire rope in the super-starting state, that is, one end of the wire rope is extended from the front end of the wire rope, and the other end is directly connected to the connecting lug of the original wire rope. Alternatively, the tension detecting devices 411 and 412 may be connected in series to the two super-lifting and pulling wires 43 and 44 of the crane. According to the technical solution of the embodiment of the present invention, the tension of the tension unit symmetrically arranged on both sides of the boom is detected, and the tension can directly reflect the size of the side load of the crane, so that the side load of the crane can be conveniently and accurately detected. In combination with the existing equipment, it is only necessary to add two tension detecting devices, and the cost increase is small. In addition, after the two tension detecting devices are added, it is convenient to determine whether the crane hoisting load is overloaded, which is more direct and accurate than the existing torque limiter load detecting method. In addition, by applying the technical solution in the embodiment, it is possible to make an effective determination on whether or not the initial bypass of the boom after the seat is prepared before the crane operation. The method is as follows: After the lifting arm is ready to be in position, try to hang a weight that is much smaller than the rated load, and detect the pulling force of the wire rope before and after the lifting of the wire rope. When the difference between the two pulling forces is greater than the allowable value, the time can be determined. The boom has a side bend and the crane must be re-adjusted to lift the work. The technical solution of the embodiment of the present invention can be applied to various cranes, such as a wheeled crane, a crawler crane, a tower crane, a rail crane, a ship crane, and the like. 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 detecting load of a crane, comprising:

Step A: detecting the tension of the tension unit symmetrically arranged on both sides of the boom, thereby obtaining two tension values;

Step B: determining whether the side load of the crane exceeds a preset range according to the two pull values, and then outputting the judgment result.

2. The method of claim 1 wherein

Determining whether the side load of the crane exceeds a preset range according to the two pull values includes: determining whether (S1+S2)/|S1-S2| is greater than a first set value, and if so, confirming the crane The side load does not exceed the preset range, otherwise it is confirmed that the side load of the crane is beyond the preset range;

Wherein, S1 and S2 respectively represent real-time tensile values of tension units symmetrically arranged on both sides of the boom under current working conditions.

3. The method of claim 1 wherein

After the step A, the method further includes: judging whether the crane is overloaded according to the size relationship between S and S1+S2, and then outputting the judgment result;

Wherein, S represents the sum of the rated tensile force values of the tension units symmetrically arranged on both sides of the crane under the current working condition, and S1 and S2 respectively represent the two real-time tensile values of the specific working condition.

The method according to claim 1, wherein after the step B, the method further comprises: repeating the step A and the step B after a preset duration.

The method according to any one of claims 1 to 4, characterized in that the tension unit symmetrically arranged on both sides of the lifting arm is two super-lifting front wire ropes or a super-lifting rear pulling wire rope of the crane.

A device for detecting load of a crane, comprising:

a receiving device, configured to receive a tensile force detection value of the tension unit symmetrically arranged on both sides of the lifting arm; and a calculating device, configured to determine, according to the two tensile values, whether the side load of the crane exceeds a preset range;

And an output device, configured to output a determination result of the computing device.

7. Apparatus according to claim 6 wherein:

The computing device is further configured to: determine whether (S1+S2)/|S1-S2| is greater than a first set value, and if yes, confirm that the side load of the crane does not exceed a preset range, otherwise confirm the crane Side load is outside the preset range;

8. Apparatus according to claim 6 or claim 7 wherein:

The computing device is further configured to: determine whether the crane is hoisted and overloaded according to a size relationship between S and S1+S2, where S represents a tension unit symmetrically disposed on both sides of the boom in the current working condition The sum of the rated tensile values below, S1 and S2 respectively represent two real-time tensile values under the current operating conditions; the output device is further configured to: output a result of a determination as to whether the crane is hoisted or not.

A system for crane load detection, comprising:

Two tension detecting devices for detecting the tension of two tension units symmetrically arranged on both sides of the crane;

a computing device, coupled to the tension detecting device, configured to determine, according to the tensile values of the two tension units, whether the side load of the crane exceeds a preset range, or determine whether the crane is suspended according to the two tensile values Heavy overload

An output device is coupled to the computing device for outputting a result of the determining by the computing device.

10. The system according to claim 9, wherein the tension detecting device has a storage element for storing the detected value of the pulling force.

A crane comprising the system for crane load detection according to claim 9 or 10.

12. The crane of claim 11 wherein:

The two tension detecting devices are respectively connected to the two super-pull-pull wire ropes of the crane, and are respectively used for detecting the pulling force of the two super-lifting front-end wire ropes of the crane; or

The two tension detecting devices are respectively connected with two super-lifting and pulling wire ropes of the crane, and are respectively used for detecting the pulling force of the two super-lifting and pulling wire ropes of the crane.