JPH1067437A - Excavation detection method and device for continuous unloader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect foward and sideway excavation force applied to an excavation part by calculating the excavation force from the inclination of a returning straight line with respect to a bending moment value at two or more height positions of a vertical transfer part having the excavation part at its lower end. SOLUTION: Bending moments MD1 , MD2 , MD3 generated by a forward excavation force F applied to an excavation part are proportional to the height to each height position P1, P2, P3 from a working point of the force FD. Measuring units each being composed of a pair of distortion gauges are mounted to a bucket elevator 17 being a vertical transfer part to the positions P1-P3. The bending moment M1 , M2 , M3 at the height positions are measured by the measurement unit, and by use of the measured values a return straight line is obtained so that the inclination of the line to the lateral axis is the forward excavation force FD. With the arrangement of paired distortion gauges (41-1a, 41-b), (41-2a, 41-2b), (41-3a, 41-3b) at the front and rear positions of the elevator 17, the forward excavation force FD can be detected and when they are arranged at the right and left positions side excavation force can be detected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bucket elevator type continuous unloader, a belt sandwiching type continuous unloader,
The present invention relates to a digging force detection method and a digging force detection device for a continuous unloader such as an SC, and more particularly to a digging force detection method and a digging force detection device for a bucket elevator type continuous unloader.

[0002]

2. Description of the Related Art A bucket elevator type continuous unloader is mainly used for unloading bulk materials such as ore, coal, and grain stored in a ship's hold. Briefly, a bucket elevator is mounted on a frame running on a quay via a boom, and this bucket elevator is inserted into a hold, and a digging section at the lower end of the bucket elevator excavates and scraps loose objects to remove the bucket. It is transported out of the hold by the elevator and landed.

[0003]

In such a bucket elevator type continuous unloader, the force acting on the unloader during the cargo handling operation, particularly the force acting on the bucket running direction of the excavation part (the front-back direction of the bucket elevator). It is effective to grasp a certain frontal excavation force and a side excavation force which is a force acting in a direction perpendicular to the frontal excavation force (right and left direction of the bucket elevator) to prevent damage to the machine due to overload. Also, if the frontal excavation force can be grasped, it can be combined with the driving force of the bucket chain and the traveling speed of the bucket,
It becomes possible to know the weight per unit time of loose items paid out from the bucket elevator.

However, the conventional bucket elevator type continuous unloader does not grasp or measure such a front excavation force or a side excavation force.

Therefore, in a continuous unloader of the type in which the lower end of the bucket elevator tilts in the traveling direction of the bucket, a method of obtaining the front excavation force from the force acting on the driving device of the bucket elevator tilting unit will be examined. The force acting on the structure of the tilting part including the excavation part provided at the lower end of the bucket elevator is a front excavation force, the gravity acting on the tilting part structure, the gravity acting on the loose object attached to the tilting part structure, The thrust force from Therefore, the force acting on the drive unit of the tilting unit is a force with respect to the moment around the rotation center of the tilting unit generated by each of the above-described forces.

Incidentally, it is difficult to measure the gravity acting on the loose objects attached to the tilting part structure during cargo handling. Moreover, the moment generated by gravity acting on the tilting portion structure and the loose objects attached thereto changes depending on the tilting angle, so that it is difficult to measure this during the cargo handling work. It is difficult to specify the point of action of the thrust force acting on the unloader tilting section using the side excavation method. Therefore, it is difficult to specify the moment generated by the front excavation force from the moments acting around the tilting unit rotation center, and to accurately determine the excavation force from the force acting on the driving device of the tilting unit.

The present invention has been made to solve such a problem, and detects a frontal excavating force acting on a digging portion in a continuous unloader and a side excavating force acting in a direction perpendicular thereto. An object of the present invention is to provide an excavation force detection method.

Another object of the present invention is to provide an excavating force detecting device suitable for the above detecting method.

[0009]

According to the present invention, there is provided a method for detecting a digging force of a continuous unloader according to the present invention, which comprises a vertical transport section suspended at the tip of a boom, and a digging section provided at a lower end of the vertical transport section. The unloader is characterized in that bending moments at two or more height positions of the vertical transport portion are measured, and a digging force is calculated from a slope of a regression line with respect to these bending moment values.

According to the present invention, there is also provided a continuous unloader having a vertical transport section hanging down at the tip of a boom and a digging section provided at a lower end of the vertical transport section. Moment measuring instruments installed to measure the bending moment at the height of the ground, and the outputs of these moment measuring instruments are supplied, and a regression line is calculated from these output values, and the excavation force is calculated from the slope. An excavating force detecting device for a continuous unloader, comprising: an arithmetic unit;

It is preferable that a low-pass filter for removing noise is provided between each of the moment measuring devices and the computing device.

In addition, the bending moment measuring device at each height position includes two detectors arranged at the same height position, and by providing these two detectors before and after the vertical transport unit. , The frontal digging force can be calculated.

Further, the bending moment measuring device at each height position includes two detectors arranged at the same height position, and by providing these two detectors on the left and right sides of the vertical transport unit. , Side excavation force can be calculated.

Preferably, a strain gauge is used for the detector.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing the overall configuration of a bucket elevator continuous unloader according to the present invention. The bucket elevator type continuous unloader includes a traveling frame 14 traveling on a rail 13 laid on a quay 12 to which a ship 11 berths, a pivoting frame 15 installed on the traveling frame 14 and capable of pivoting in a horizontal plane, Frame 1
5 and a boom 1 pivotally supported by the
6, a bucket elevator (vertical transport unit) 17 rotatably supported at the tip of the bucket elevator 6 and vertically suspended, and a digging unit 18 provided at a lower end of the bucket elevator 17
And

Further, the bucket elevator 17 is provided with an elevator casing 19 for covering the bucket, and a swing frame 20 between the lower end of the elevator casing 19 and the excavation section 18.
The excavating portion 18 can be tilted in the traveling direction (front-back direction) of the bucket by the first hydraulic cylinder mechanism 21 incorporated in the inside of the cylinder. Here, the front-back direction of the bucket elevator (vertical transport unit) 17 is defined as the traveling direction of the bucket of the excavating unit 18, and the left-right direction is defined as the direction perpendicular to the traveling direction of the bucket. The structure including the excavation unit 18 and the swing frame 20 is called a tilting unit structure. The excavating section 18 is configured so that a bucket provided on a bucket chain 24 moves in the longitudinal direction in order to excavate and scrape loose objects 23 stored in the hold 22. Excavated loose objects 23,
When scraping, the excavating part 18 moves in the hold 22,
This movement is performed by the traveling of the traveling frame 14, the turning frame 1
5 turning, boom 16 undulation and bucket elevator 1
7, that is, rotation about the central axis of the bucket elevator 17.

On the other hand, the boom 16 is pivotally supported by the revolving frame 15 by a second hydraulic cylinder mechanism 25 so as to be able to move up and down. The boom 16 is provided with a boom conveyor 26, and conveys loose objects from the bucket elevator 17 to the turning frame 15 side. Boom 1 from turning frame 15
The arm 27 extends in the direction opposite to the direction
Is provided with a balance weight 28 at the tip thereof. Thus, the boom 16 and the arm 27 can perform a so-called seesaw motion with the upper portion of the turning frame 15 as a fulcrum.

As described above, the loose objects 23 stored in the hold 22 are excavated and scraped by the excavation unit 18, and then conveyed upward by the bucket elevator 17, and moved out of the hold 22 by the boom conveyor 26. Conveyed.

In such a bucket elevator type continuous unloader, the front digging force acting on the digging portion 18 (the digging force of loose objects acting in the running direction of the bucket) FD,
Bending moments M1, M2, and M3 acting on different height positions P1, P2, and P3 of the vertical portion that does not tilt in the structure constituting the bucket elevator 17 are as shown in FIG. That is, among the forces acting on the tilting portion structure including the excavation portion 18 and the swing frame 20, the gravity acting on the tilting portion structure, the gravity acting on the loose object attached to the tilting portion structure, and the pushing force are different. Height position P1,
The same moment M _ER is obtained for P2 and P3.

On the other hand, the bending moments M _D1 , M _D2 , M _D3 due to the front digging force FD acting on the digging portion 18 are long from the point of _application of the digging force FD to the respective height positions P1, P2, P3. Proportional to As shown in FIG. 4, measuring instruments 41-1, 41-2, 41-3 formed of strain gauges are installed in the bucket elevator 17 at each of these height positions P1, P2, P3. These measuring devices 41-1, 41-2,
According to 41-3, bending moments M1 and M at each height position
2, M3 is measured, and the regression line 51 is obtained as shown in FIG. 5 using these values. The inclination of the regression line 51 with respect to the horizontal axis is the front excavation force FD.

The measuring devices 41-1, 41-2, 41
-3 are two strain gauges 41-1a and 41-1a, respectively.
1b, 41-2a, 41-2b, 41-3a, 41-3
3, the front excavation force FD can be detected by arranging two strain gauges at the same height position before and after the bucket elevator 17 as shown in FIG. On the other hand, by arranging two strain gauges at the same height position on the left and right sides of the bucket elevator 17, the side excavation force FD 'can be detected as described later. The reason why two strain gauges are used at a certain height position is to remove an error component caused by vertical expansion and contraction acting on the bucket elevator 17. Therefore, each measuring device 41-1 and 4
The outputs of 1-2 and 41-3 are the difference components between the outputs of the two strain gauges. If the error component as described above can be neglected, each of the measuring devices 41-1, 41-2, 41-3 may be constituted by one strain gauge, or another bending moment may be used instead of the strain gauge. May be used.

Here, FIG. 5 shows each measuring device 41- on the horizontal axis.
It is the graph which plotted the measured value of each measuring device 41-1, 41-2, 41-3 taking the moment value on the height position of 1, 41-2, 41-3, and a vertical axis | shaft. The distances L1 and L2 on the horizontal axis in FIG. 5 are the measuring instruments 41-1 and 41-2 in FIG.
And the distance between the measuring instruments 41-2 and 41-3.

FIG. 4 is a block diagram of an apparatus for automatically obtaining the regression line 51 shown in FIG. Measuring instruments 41-1 to 4
The output signals of 1-3 are low-pass filters 42-1, 42-2, 42-3 for removing high-frequency components such as noise, respectively.
The output signal indicating the bending moment value is supplied to the arithmetic unit 43. The computing unit 43 performs a regression analysis on the output signals indicating the respective bending moment values, and obtains a front excavation force FD from the slope of the regression line.

FIG. 6 shows another embodiment, in which a strain gauge 41- as a detector for determining the side excavation force FD '.
1a ', 41-1b', 41-2a ', 41-2b',
It is a figure which shows the installation state of 41-3a 'and 41-3b'. As shown in FIG. 6, each detector is installed in the left-right direction around the vertical portion of the bucket elevator 17 with respect to each installation position in FIG. In other words, as described above, the arrangement direction of the two detectors in each measuring device is set to be perpendicular to the traveling direction of the bucket of the excavation unit 18. Other configurations are the same as those in FIG.
Corresponding components are denoted by corresponding reference numerals, and description thereof is omitted.

Incidentally, as shown in FIG.
-3a, 41-3b are these strain gauges 41-3a,
Although the line segment connecting 41-3b is provided in the same direction as the front-back direction of the bucket elevator 17, it may be slightly shifted.

Although the above example describes the measurement of front / side excavation forces acting on a cargo handling device having a vertical transport path between the excavation section and the boom conveyor, the present invention relates to, for example, a chain conveyor type continuous unloader, The present invention can also be applied to a belt sandwiching type continuous unloader, VSC, and the like.

[0027]

According to the present invention described above, it is possible to detect only the front excavation force and the side excavation force from various forces acting on the bucket elevator structure. In addition, since the measurement points of the bending moment are about two or three points in the vertical direction of the bucket elevator, the amount of calculation for obtaining the regression line is small, and the front excavation force and the side excavation force are almost real-time. Can be detected.

[Brief description of the drawings]

FIG. 1 is a diagram showing an overall configuration of a bucket elevator type continuous unloader to which the present invention is applied.

FIG. 2 is an explanatory view showing the magnitude of a bending moment acting on different height positions of a bucket elevator shown in FIG. 1;

FIG. 3 is a cross-sectional view of the bucket elevator shown in FIG.

FIG. 4 is a block diagram showing an embodiment of an excavating force detecting device according to the present invention.

FIG. 5 is a graph showing a regression line showing the principle of the excavation force detection method of the present invention.

FIG. 6 is an explanatory diagram showing the magnitude of a bending moment acting on different height positions of a bucket elevator according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Ship 12 Wharf 13 Rail 14 Running frame 15 Revolving frame 16 Boom 17 Bucket elevator 18 Excavation part 19 Elevator casing 20 Swing frame 21 1st hydraulic cylinder mechanism 22 Hold 23 Bulk material 24 Bucket chain 25 2nd hydraulic cylinder mechanism 26 Boom Conveyor 27 Arm 41-1, 41-2, 41-3 Measuring device 42-1, 42-2, 42-3 Low-pass filter 43 Arithmetic unit

Claims (8)

[Claims] 1. A continuous unloader comprising a vertical transfer section hanging down at the tip of a boom and a digging section provided at a lower end of the vertical transfer section, wherein the vertical transfer section has two or more height positions. A method for detecting a digging force of a continuous unloader, comprising: measuring a bending moment; and calculating a digging force from a slope of a regression line with respect to the bending moment value. 2. The excavating force detecting method according to claim 1, wherein the bending moment at each height position is measured at two positions at the same height position, and these measurements are performed before and after the vertical transport unit. The excavation force detecting method for a continuous unloader, wherein the excavation force is calculated by the following formula: 3. The excavating force detecting method according to claim 1, wherein the bending moment at each height position is measured at two locations at the same height position, and these measurements are performed on the left and right sides of the vertical transport unit. A method for detecting a digging force of a continuous unloader, wherein the digging force is calculated by the following formula: 4. A continuous unloader comprising a vertical transport section suspended at the tip of a boom and a digging section provided at a lower end of the vertical transport section, wherein the vertical transport section is provided at two or more height positions. A moment measuring device installed to measure the bending moment, and an arithmetic unit that is supplied with the outputs of these moment measuring devices, calculates a regression line from these output values, and calculates the excavating force from its slope. An excavating force detecting device for a continuous unloader. 5. The excavating force detecting device according to claim 4, wherein a low-pass filter for removing noise is provided between each of the moment measuring devices and the computing device. apparatus. 6. The excavating force detecting device according to claim 4, wherein the bending moment measuring device at each height position includes two detectors arranged at the same height position, and the two detections are performed. An excavating force detecting device for a continuous unloader, wherein a front excavating force is calculated by providing a vessel before and after the vertical transport unit. 7. The excavating force detecting device according to claim 4, wherein the bending moment measuring device at each height position includes two detectors arranged at the same height position, and the two detections are performed. An excavating force detecting device for a continuous unloader, wherein side excavating forces are calculated by providing containers on the left and right sides of the vertical transport unit. 8. The excavating force detecting device for a continuous unloader according to claim 6, wherein a strain gauge is used as the detector.