Boom work range determination system for mobile crane

Abstract

To provide a boom work range determination system for a mobile crane that is applicable even to an existing mobile crane and is able to inform a worker of the suitability of a work range of a boom.SOLUTION: A boom work range determination system for a mobile crane includes: first measurement means 12; second measurement means 14; third measurement means 16; and a mobile terminal 18 including storage means 20 that stores at least a rated load diagram of a work vehicle 50, input means 22 that selects a vehicle type of the work vehicle 50 and inputs a suspension load, and calculation means that calculates a work radius of a telescopic boom 54 based on measurement values measured by the second measurement means 14 and the third measurement means 16, compares an allowable work radius with the work radius, the allowable work radius being obtained by applying the suspension load input via the input means, and an amount of overhang of an outrigger measured via the first measurement means, to the rated load diagram, and determines whether the work radius is equal to or less than the allowable work radius.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a device for determining whether the boom working range of a mobile crane is acceptable, and more particularly to a system that enables retrofitting to determine whether the working range is acceptable. [Background technology]

[0002] The boom working range of a mobile crane is determined by factors such as the extension of the outriggers and the vehicle characteristics (e.g., weight) that make up the mobile crane, within a range that ensures safety. For this reason, conventionally, measures such as placing traffic cones (registered trademark) along the predetermined working range have been taken, and the crane has been operated to ensure that the boom does not exceed this working range. However, in practice, it is difficult to accurately determine the positional relationship between the tip of the boom and traffic cones (registered trademark) placed on the ground, and there have been cases where the tip of the boom has exceeded the set working range while work is being carried out.

[0003] In light of these circumstances, a safety device for a mobile crane is disclosed in Patent Document 1. The safety device for a mobile crane disclosed in Patent Document 1 is configured to set a working range that allows crane operation with the maximum rated total load (hanging load) based on the extension amount and extension angle of the outriggers. If a crane operation instruction is given that exceeds the preset working range, an overload prevention function is activated to forcibly stop the crane operation.

[0004] A mobile crane safety device configured in this way makes it impossible to carry out work that falls outside the work area where safety has been taken into consideration, and is therefore thought to be able to achieve a high level of safety.

[0005] However, the above-mentioned safety devices for mobile cranes are attached to new mobile cranes, and are difficult to retrofit onto existing mobile cranes, so the reality is that they do not actually contribute to improving the safety of work using mobile cranes. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] WO2018 / 147388 publication Summary of the Invention [Problem to be solved by the invention]

[0007] In view of the above-described circumstances, the present invention aims to provide a mobile crane boom working range determination system that can be applied to existing mobile cranes and that can inform workers whether the boom working range is appropriate. [Means for solving the problem]

[0008] In order to achieve the above object, the present invention provides a boom working range determination system for a mobile crane, which is a boom working range determination system for a work vehicle equipped with a telescopic boom, and comprises: a first measurement means that can be attached to the outside of the work vehicle and measures the extension amount of the outriggers attached to the work vehicle; a second measurement means that can be attached to the outside of the work vehicle and measures the inclination angle of the telescopic boom; a third measurement means that can be attached to the outside of the work vehicle and measures the length of the telescopic boom; storage means that stores a rated load diagram that shows the relationship between at least the rated lifting load and the working radius determined for each type of work vehicle; a mobile terminal having an input means for selecting the type of work vehicle and inputting the hanging load; a calculation means for calculating the working radius of the telescopic boom based on the measurement values ​​measured by the second measurement means and the third measurement means, and for comparing the working radius with an allowable working radius obtained by applying the hanging load input via the input means and the extension amount of the outrigger measured via the first measurement means to the rated load diagram, and determining whether the working radius is equal to or less than the allowable working radius; and a display means for visibly outputting the options for the work vehicle selected by the input means, the input value of the hanging load, and the result of the determination.

[0009] In addition, in the mobile crane boom working range determination system having the above-mentioned features, it is preferable that the extension amount of the outriggers be determined by adding together a fixed value from the vehicle center to the vehicle width range and the displacement measured by the first measurement means. With such features, it is possible to calculate the extension amount of the outriggers from the vehicle center.

[0010] In addition, in the mobile crane boom working range determination system having the above-mentioned features, it is preferable that the length of the telescopic boom be determined by adding together the fixed value from the movable base point of the telescopic boom to the tip of the base portion that does not telescope and the measurement value measured by the third measuring means. With such features, it is possible to calculate the working radius based on the actual length of the boom.

[0011] In addition, in the mobile crane boom working range determination system having the above-mentioned features, it is desirable that the mobile terminal has a communication function so that the determination results can be transferred to an external system. With such a feature, the determination results can be used in other systems.

[0012] Furthermore, in a mobile crane boom working range determination system having the above-described features, if a determination result is given that the working radius exceeds the allowable working radius and this condition continues for a predetermined time, a warning is preferably sent to a work supervisor. With such features, it is possible to notify the work supervisor of the working status and take measures to improve the safety of the actual work. [Effects of the Invention]

[0013] The mobile crane boom working range determination system with the above features can be applied to existing mobile cranes and can inform the operator whether the boom working range is appropriate. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a block diagram showing the configuration of a boom working range determination system for a mobile crane according to an embodiment. [Figure 2] 1 is a side view for explaining an example in which a boom working range determination system for a mobile crane according to an embodiment is attached to a mobile crane (work vehicle). FIG. [Figure 3] 1 is a plan view for explaining an example in which a boom working range determination system for a mobile crane according to an embodiment is attached to a mobile crane (work vehicle). FIG. [Figure 4] FIG. 10 is a diagram showing an example of a screen displayed on a display unit. [Figure 5]1 is a flowchart illustrating a processing flow of a boom working range determination system for a mobile crane according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, embodiments of a mobile crane boom working range determination system according to the present invention will be described in detail with reference to the drawings. Note that the embodiments shown below are only a portion of the embodiments for carrying out the present invention, and even if a portion of the configuration is changed, it can be considered as part of the present invention as long as the effects of the system are achieved.

[0016] [composition] First, referring to FIG. 1, the configuration of a mobile crane boom working range determination system (hereinafter simply referred to as the determination system 10) according to this embodiment will be described. The determination system 10 according to this embodiment is basically composed of a first measurement means 12, a second measurement means 14, a third measurement means 16, and a mobile terminal 18. The first measurement means 12 is an element for measuring the extension amount of an outrigger 52 provided on a work vehicle 50 (see FIGS. 2 and 3), which is a mobile crane. Specifically, it may be a distance measurement sensor such as a Time of Flight (TOF) sensor. The extension amount of an outrigger 52 on a work vehicle 50 generally refers to the distance from the center of the vehicle to the support portion located at the tip of the outrigger 52. For this reason, the distance from the center of the vehicle that is half the vehicle width is set as a fixed value Y, and the variations D, E, F, and G of each outrigger 52 are set as measured values. The sum of the fixed value Y and the variations (measured values) D, E, F, and G is set as the extension amount M of each outrigger 52 (see FIG. 3).

[0017] The placement location of the first measurement means 12 is not critical as long as it is possible to measure the degree of outrigger extension. In this embodiment, as shown in FIG. 3, the main body of a TOF sensor serving as the first measurement means 12 is placed on the side of the work vehicle 50, and measurements are performed using the tips of the outriggers 52 as targets 12a. Furthermore, the same number of first measurement means 12 as the number of outriggers 52 must be placed. The work vehicle 50 shown in FIG. 3 is equipped with four outriggers 52, so the four first measurement means 12 can measure the extension amounts of the outriggers 52 at four locations: the right front wheel, the left front wheel, the right rear wheel, and the left rear wheel. It is preferable that the thickness of the first measurement means 12 and the target 12a be negligible or be added to the measurement value in advance.

[0018] As shown in Figure 2, the second measuring means 14 is an element for measuring the tilt angle of the telescopic boom 54 of the work vehicle 50. Specifically, it may be an inclination sensor, an acceleration sensor, a gyro sensor, or the like. The tilt angle of the telescopic boom 54 may be the tilt angle θ from the horizontal plane where the base point O for raising and lowering the telescopic boom 54 is located. Note that the mounting position of the second measuring means 14 is not limited to a specific arrangement, as long as it is on the telescopic boom 54.

[0019] The third measuring means 16 is an element for measuring the extension of the telescopic boom 54 of the work vehicle 50. Specifically, it may be a TOF sensor similar to the first measuring means 12, or a wire-type displacement meter. This is because by configuring the wire of the wire-type displacement meter to be pulled out as the telescopic boom 54 extends, it becomes possible to detect the amount of displacement of the telescopic boom 54.

[0020] In this embodiment, it is necessary to calculate the working radius of the telescopic boom 54. Therefore, the length of the telescopic boom 54 needs to be determined not just by the amount of displacement due to extension, but also by the overall length of the telescopic boom 54. Therefore, the length of the boom is determined by setting the distance from the base point (base point O) of the boom to the tip of the telescopic base (the non-extending portion) as a fixed value X, and the extending portion as a measured value A, and the sum of these values ​​is the length L of the telescopic boom 54. The arrangement of the third measurement means 16 is not limited as long as it can measure the change in the extension of the telescopic boom 54. In the example shown in FIG. 2, the third measurement means 16 is a TOF sensor, and a target 16a is placed at the tip of the telescopic boom 54. The thickness of the target can be ignored or added to the measurement value in advance.

[0021] In this way, the measuring means of this embodiment (first measuring means 12, second measuring means 14, third measuring means 16) can all be retrofitted to the outside of an existing work vehicle 50.

[0022] The mobile terminal 18 is an element that calculates the working radius of the telescopic boom 54 based on the measurements taken via the first measuring means 12 to the third measuring means 16 described above, and determines whether the weight of the load (hanging load) planned for work at this working radius falls within the allowable range. The mobile terminal 18 according to this embodiment that performs these functions has at least a storage means 20, an input means 22, a calculation means 24, and a display means 26.

[0023] The storage means 20 is an element for storing at least specification information for each type of work vehicle 50 and information relating to a rated load diagram showing the relationship between the rated lifting load and the working radius. The storage means also serves to temporarily store input values ​​via the input means 22 and values ​​calculated via the calculation means. Specific examples of the storage means 20 include an HDD, an SSD, and memory.

[0024] The input means 22 is an element for selecting the type of work vehicle 50 and inputting the weight of the suspended load, i.e., the suspended load. A specific example of the input means 22 can be a touch panel that uses the display means 26. By using the display means 26 and the input means 22 as a common element, there is no need to provide a separate input means 22, and the mobile terminal 18 can be made smaller.

[0025] The calculation means 24 is an element that calculates the working radius R1 of the telescopic boom 54 based on the tilt angle θ and length L of the telescopic boom 54 obtained via the second measurement means 14 and the third measurement means 16, and determines whether the calculated working radius R1 is within the range of the allowable working radius R0 in the rated load diagram. Specifically, the calculation means 24 calculates the allowable working radius R0 by applying the extension amount M of the outrigger 52 obtained via the first measurement means 12 and the suspended load input via the input means 22 to the rated load diagram corresponding to the type of work vehicle selected via the input means 22. The calculation means 24 then compares the working radius R1 with the allowable working radius R0, and if the working radius R1 is equal to or less than the allowable working radius R0, it determines whether to issue a work permit, or if the working radius R1 exceeds the allowable working radius R0, it determines whether to issue a warning to halt work.

[0026] The display means 26 is an element for visually displaying measurement values, determination results, etc. Specifically, it is sufficient if it can visually display the contents input via the input means 22, the contents measured or calculated via the first measurement means 12 to the third measurement means 16, and the results of determination via the calculation means 24. An example of a display screen by the display means 26 is shown in FIG. 4.

[0027] The example of the display screen shown in Fig. 4 is provided with a display unit that displays the boom length, which indicates the length of the telescopic boom, and measured values ​​(calculated values) for the right front (front wheel right) side, left front (front wheel left) side, right rear (rear wheel right) side, and left rear (rear wheel left) side. The example of the display screen also shows the value input via the input means or input as a measured value by a sensor or the like as the suspended load. Furthermore, the display means 26 has a display item for the calculated working radius (shown as 3.5 m in Fig. 4) and an allowable work judgment that indicates whether the working radius is within the allowable working radius range ("OK" or "NG").

[0028] [Actions and Effects] Next, the flow of determining the allowable work range using the determination system 10 configured as described above will be described with reference to Figure 5. It is assumed that the first measurement means 12, the second measurement means 14, and the third measurement means 16 are installed in advance on the work vehicle 50.

[0029] First, the work vehicle 50 is parked at the work position and the outriggers 52 are extended for work. At this time, measurement of the displacement amount by the first measurement means 12 begins. The measured values ​​(measurement values ​​D, E, F, G) are transmitted to the mobile terminal 18 via short-range wireless communication. In the mobile terminal 18 that receives the measurement values ​​from the first measurement means 12, the calculation means 24 reads out a specification table for the corresponding vehicle model recorded in the storage means 20 based on the pre-selected vehicle model of the work vehicle 50, and extracts a fixed value Y from the vehicle center. The extracted fixed value Y is added to each of the measurement values ​​(D, E, F, G) measured via the first measurement means 12, and the extension amount M of the outriggers 52 is calculated. Here, the calculation of the extension amount of the outriggers 52 is repeated the number of times equal to the number of outriggers 52 provided on the work vehicle 50 (the number of first measurement means 12) (S10).

[0030] Next, the calculation means 24 reads out the rated load diagram corresponding to the work vehicle 50, and calculates the allowable working radius R0 from the suspended load and extension amount M of the outriggers 52 input via the input means 22 (S20). The calculated allowable working radius R0 is temporarily saved in the storage means 20, and the length L of the telescopic boom 54 is calculated by adding the measured value A obtained via the third measurement means 16 and a fixed value X based on the specifications (S30).

[0031] Based on the angle θ of the telescopic boom 54 measured via the second measuring means 14 and the length L of the telescopic boom 54, the working radius R1 is calculated using a trigonometric function (Equation 1) (S40).

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[0032] After the working radius R1 is calculated in S40, the allowable working radius R0 temporarily stored in the storage means 20 is read out and compared with the working radius R1. If the comparison result satisfies the relationship in Equation 2, the tip of the telescopic boom 54 is within the range of the allowable working radius R0, meaning that work can be carried out safely (S50).

number

[0033] Therefore, if the comparison shows that the working radius R1 is equal to or less than the allowable working radius R0, a determination is made that the working radius is normal, and "OK" or "normal" is displayed in the item for outputting the determination result in the display means 26 (allowable work determination) (S60). On the other hand, if the working radius R1 is greater than the allowable working radius R0, a determination is made that the working radius is abnormal, and "NG" or "abnormal" is displayed in the item for outputting the determination result in the display means 26. Note that when "NG" is output as the determination result, in addition to displaying it in the display means 26, a warning may be issued by sound or light via warning means (not shown) (S70).

[0034] If the display means 26 shows a judgment result indicating "NG," the worker holding the mobile terminal 18 should perform processing to narrow the range of the working radius R1 by, for example, increasing the tilt angle θ of the telescopic boom 54 or shortening the length L of the telescopic boom 54.

[0035] The above-described judgment system 10 can be applied to existing mobile cranes (work vehicles 50), and can inform workers of the suitability of the working range (working radius R1) of the telescopic boom 54.

[0036] [Application form] In the judgment system 10 configured as described above, by equipping the mobile terminal 18 with a communication function, it becomes possible to transmit the propriety of the work status to an external organization, etc. Therefore, for example, if during work status, the display means 26 continues to show "NG" in the allowable work judgment item for a certain period of time, it becomes possible to send a warning to the work instructor such as the construction manager or the construction manager that work is being performed in a dangerous condition.

[0037] Furthermore, the determination results by the determination system 10 can be stored as a work record (evidence) in the cloud or in an external organization. Furthermore, in the above embodiment, the extension amount M of each outrigger 52 is the sum of a fixed value Y and variations D, E, F, and G. However, if the extension amount of the outrigger 52 shown in the rated load diagram is shown as a converted value (for example, one that shows a stepwise change such as full extension and 1 / 2 extension), the measurement value by the first measuring means 12 may be converted into the converted value and used.

[0038] For example, if a load rating diagram showing the relationship between the lifting load rating and the working radius shows a relationship curve between "fully extended" and "half extended" as the extension of the outriggers 52, the ratio of the measured values ​​can be calculated by assuming that the fully extended length of the outriggers 52 for each work vehicle 50 (the state where the amount of change is maximum) is 1. If the converted value of the measured value is less than 1 / 2 as the extension of the outriggers 52, the extension is determined to be 0, and if the converted value is between 1 / 2 and 1, the extension is set to 1 / 2. Furthermore, if the converted value is 1, the extension is set to 1 (fully extended), and the working radius for the rated load (hanging load) can be calculated. Note that by rounding down the converted value if it is less than the specified value, it is possible to increase the safety factor of the working radius for the rated load. [Industrial Applicability]

[0039] The above description only explains how the determination system 10 issues a warning or the like in response to the determination result and stores it. However, the determination result obtained by the determination system 10 according to the embodiment may be used in the processing of another system. For example, if linked to a work record creation system, the determination result can be recorded in the work record. Furthermore, if linked to the starter system of the work vehicle 50, if an NG message appears in the allowable work determination item on the display means 26, or if the NG message continues to appear for a certain period of time, it is possible to stop the engine of the work vehicle 50 and take measures to prevent the work from continuing. [Explanation of symbols]

[0040] 10...Determination system, 12...First measurement means, 12a...Target, 14...Second measurement means, 16...Third measurement means, 16a...Target, 18...Mobile terminal, 20...Memory means, 22...Input means, 24...Calculation means, 26...Display means, 50...Work vehicle, 52...Outrigger, 54...Telescopic boom.

Claims

1. A boom working range determination system for a work vehicle equipped with a telescopic boom, a first measuring means that can be attached to the outside of the work vehicle and that measures the extension amount of an outrigger provided on the work vehicle; a second measuring means that can be attached to the outside of the work vehicle and that measures the tilt angle of the telescopic boom; a third measuring means that can be attached to the outside of the work vehicle and that measures the length of the telescopic boom; a mobile terminal having at least a storage means for storing a rated load diagram showing the relationship between the lifting capacity rating and the working radius determined for each type of work vehicle; an input means for selecting the type of work vehicle and inputting the hanging load; a calculation means for calculating the working radius of the telescopic boom based on the measurement values ​​measured by the second measurement means and the third measurement means, comparing the working radius with an allowable working radius obtained by applying the hanging load input via the input means and the extension amount of the outrigger measured via the first measurement means to the rated load diagram, and determining whether the working radius is equal to or less than the allowable working radius; and a display means for visibly outputting the options for the work vehicle selected by the input means, the input value of the hanging load, and the result of the determination.

2. 2. The mobile crane boom working range determination system according to claim 1, wherein the extension amount of the outrigger is calculated by adding together a fixed value from the center of the vehicle to the vehicle width range and the displacement amount measured by the first measuring means.

3. 3. The mobile crane boom working range determination system according to claim 2, wherein the length of the telescopic boom is determined by adding together a fixed value from the movable base point of the telescopic boom to the tip of the base portion that does not telescope and a measurement value measured by the third measurement means.

4. 4. A mobile crane boom working range determination system according to claim 1, wherein the mobile terminal is provided with a communication function and is configured to be able to transfer the results of the determination to an external system.

5. 5. The mobile crane boom working range determination system according to claim 4, wherein when a determination result is given that the working radius exceeds the allowable working radius, and this condition continues for a predetermined time, a warning is sent to a work instructor.

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