JPH10250850A - Quantitative cargo handing control method and control device for continuous unloader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make quantitative cargo handling possible by relatively computing the computed cargo handling capacity of an unloader and the cargo handling capacity target value, and controlling the unloader in such a way that the computed cargo handling capacity becomes the cargo handling capacity target value. SOLUTION: A relative computing element 42 outputs the relative deviation of cargo handling capacity WN obtained by a cargo handling capacity computing element 41 and cargo handling capacity target value WT to a motor controller 43 for controlling a bucket chain driving motor 45, and a traverse controller 44 for controlling a traveling motor 46-1, a boom turning motor 46-2, a boom hoisting cylinder 46-3, a bucket elevator turning motor 46-4 and a tilt cylinder 46-5 of tilt mechanism. The motor controller 43 and the traverse controller 44 respectively outputs commands to reduce bucket chain speed (vc) and to reduce traverse speed in order to reduce scraped area in case of WN>WT and commands to increase bucket chain speed (vc) and to increase traverse speed in order to increase scraped area in case of WN<WT.

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, and more particularly, to a control method and a control device for realizing a constant load operation.

[0002]

2. Description of the Related Art Bucket elevator type continuous unloaders are mainly used for unloading bulk materials, such as ore, coal, or grain, stored in a ship's hold. Simply put, a bucket elevator is mounted on a frame running on the quay via a boom, and this bucket elevator is inserted into a hold, and a drilling section at the lower end of the bucket elevator excavates and scrapes loose objects, thereby obtaining a bucket elevator. Transported out of the hold and landed.

[0003] In such a bucket elevator type continuous unloader, to prevent an excessive load from being applied to the rear transport path and to optimize the equipment, the unloader is provided with a fixed amount of bulk material per unit time. Pay out,
So-called quantitative cargo handling is required. This quantitative cargo handling can be realized by predicting the cargo handling capacity of the unloader and adjusting the operating conditions such as the excavation depth, the moving speed of the machine, and the speed of the in-machine conveyor.

[0004]

For the purpose described above, the following two methods have conventionally been used as methods for determining the most important unloading ability of the unloader.

[0005] The first method is to calculate the volume of loose objects to be scraped from the excavation depth and the moving path and speed of the unloader excavator, and obtain the cargo handling capacity from the density of the loose objects and the moving speed of the bucket chain. is there. However, in this method, when the bucket scraps loose objects, the loose objects fall off, so that the calculated value may not match the actual value.

The second method is to predict the cargo handling capacity of the unloader from the driving force of the bucket chain. FIG.
0 shows the result of predicting the cargo handling capacity by this method. The curve WO shown by the solid line in the figure shows the predicted cargo handling capacity, and WH shown by the broken line is the actual cargo handling capacity. As is clear from the figure, the predicted cargo handling capacity WO does not match the actual cargo handling capacity WH, and the former is about 20% larger than the latter. This is because the excavation resistance is added in addition to the lifting force of the loose object.

FIG. 11 shows the relationship between the driving force of the bucket chain and the cargo handling capacity during coal cargo handling and iron ore cargo handling. Although there is a linear relationship between the bucket chain driving force and the cargo handling capacity, the inclination of the straight line differs depending on the type of loose objects. This is because the specific gravity and density of the loose objects are different.

As is apparent from the above description, the conventional method has a problem in accurately grasping the cargo handling capacity, and therefore, it has been difficult to realize the quantitative cargo handling.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a method for controlling the continuous unloading of a continuous unloader capable of accurately predicting the cargo handling capacity and realizing the quantitative cargo handling.

Another object of the present invention is to provide a quantitative cargo handling control device suitable for the above control method.

[0011]

According to the present invention, there is provided a vertical transport section suspended at the tip of a boom, an excavating section provided at a lower end of the vertical transport section, and a rose scraped by the excavating section. In a continuous unloader provided with a bucket chain for transporting an object to the upper end of the vertical transport section, the frontal excavation force FD and the driving loss FR of the bucket chain are subtracted from the driving force FM acting on the bucket chain to obtain the weight of the excavated object.
L is obtained and multiplied by the bucket chain speed vc,
By dividing by the head H of the vertical transport unit, a cargo handling capacity WN of the unloader is calculated, and the cargo handling capacity WN is compared with a preset cargo handling capacity target value WT to calculate the cargo handling capacity WN. A method for controlling the unloading of a continuous unloader, characterized in that the unloader is controlled to reach the target value WT.

[0012] More specifically, a vertical transport section hung at the tip of the boom, an excavation section provided at the lower end of the vertical transport section, and loose objects scraped by the excavation section are transferred to the vertical transport section. In a continuous unloader provided with a bucket chain that conveys at the upper end, a motor that drives the bucket chain, a torque meter that measures the torque of this motor, a tachometer that measures the number of revolutions of the motor, A bending moment measuring instrument fixed at a different height position, and calculating a digging force FD acting on the excavated portion from a slope of a regression line with respect to a bending moment value obtained from the bending moment measuring instrument. Then, the driving force FM acting on the bucket chain is calculated using the measurement result of the torque meter, and the speed vc of the bucket chain is calculated using the measurement result of the tachometer. Then, the driving loss FR of the bucket chain is measured in advance, and the unloading capacity WN of the unloader is calculated using the calculation results, and the calculated unloading capacity WN is compared with a preset set value WT. Then, a quantitative unloading control method for the continuous unloader, characterized by controlling the speed of the bucket chain or the traversing speed of the excavation part, so that the unloading capacity WN becomes the target unloading capacity value WT.

According to the present invention, there is also provided a vertical transport section hanging down at the tip of the boom, a digging section provided at a lower end of the vertical transport section, and a bulk transported by the digging section. A continuous unloader having a bucket chain for transporting at the upper end thereof, a motor for driving the bucket chain, a torque meter for measuring a torque of the motor, a tachometer for measuring the number of rotations of the motor, A bending moment measuring instrument fixed at different height positions of the section, and a digging force acting on the excavating section is calculated from a slope of a regression line with respect to a bending moment value obtained from the bending moment measuring instrument. A first calculator, a second calculator for calculating the driving force of the bucket chain using the measurement result of the torque meter, and the bucket chain using a measurement result of the tachometer. A third computing unit for calculating the speed of the unloader, a fourth computing unit for calculating the unloading capability of the unloader using the calculation results of the first to third computing units, and A comparison computing unit that performs a comparison operation with a preset cargo handling capacity target value and outputs a deviation thereof, and a control unit that controls an unloader based on the deviation so that the cargo handling capacity becomes the cargo handling target value. And a quantitative unloading control device for the continuous unloader.

The control means may include at least one of a motor controller that controls the speed of the bucket chain based on the deviation and a traverse controller that controls the traversing speed of the excavation section based on the deviation. It is preferable to provide

Further, each of the moment measuring instruments and the first
It is preferable to provide a low-pass filter for removing noise between the arithmetic units.

Further, the bending moment measuring devices at the respective height positions are two strain gauges arranged at the same height position, and the two strain gauges are provided before and after the vertical transport unit. It is preferable to calculate the frontal excavation force.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 is a diagram showing the entire configuration of the bucket elevator type continuous unloader of 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 which covers the bucket elevator 17 and a swing frame 20 between the lower end of the elevator casing 19 and the excavation section 18 and is incorporated in the swing frame 20. The first hydraulic cylinder mechanism 21 allows the excavating section 18 to be tiltable in the traveling direction (back and forth direction) of the bucket 24. Here, the front-back direction of the bucket elevator (vertical transport unit) 17 is defined as the traveling direction of the bucket 24 of the excavating unit 18, and the left-right direction is defined as a direction perpendicular to the traveling direction of the bucket 24.

The structure including the excavation portion 18 and the swing frame 20 is called a tilting portion structure. The excavating unit 18 excavates and scrapes the loose objects 23 stored in the hold 22,
The bucket 24 provided on the bucket chain 31 moves in the longitudinal direction. 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 that the boom 16 can be raised and lowered. 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.

FIG. 3 is an enlarged view of the bucket elevator 17 and the excavation section 18 of FIG. A sprocket 32 for driving a bucket chain 31 is provided at an upper end of the bucket elevator 17. An output shaft of a bucket chain drive motor 33 is connected to a rotation shaft of the sprocket 32 via a speed reducer. The bucket chain drive motor 33 is provided with a torque meter 34 for measuring the shaft torque and a tachometer 35 for measuring the motor speed.

On the other hand, among the structures constituting the bucket elevator 17, the bending moment measuring device 36-1 composed of a strain gauge is located at different height positions P1 and P2 of the vertical portions.
a, 36-1b, 36-2a, and 36-2b. These bending moment measuring instruments 36-1a, 36
-1b, 36-2a and 36-2b are used to determine the frontal digging force (the digging force of loose objects acting in the running direction of the bucket) FD acting on the digging section 18 from the measured values M1 and M2 which are the difference between these values. belongs to. Bending moment measuring instrument 36-
1a and 36-1b, 36-2a and 36-2b are arranged in the front-back direction of the bucket elevator 17, respectively.

The front excavation force FD can be obtained as follows. Bending moments M1, acting on different height positions P1, P2 of the vertical part of the bucket elevator 17,
M2 is, as shown in FIG. 3, of the forces acting on the tilting part structure including the excavation part 18 and the swing frame 20.
Gravity acting on the tilting part structure, the gravity acting on roses substance attached to the tilt unit structures, push-up force is the same moment M _ER for different height positions P1, P2.

On the other hand, the bending moments M _D1 and M _D2 due to the front digging force FD acting on the digging portion 18 are determined by the digging force F _D
It is proportional to the length from the action point of D to each of the height positions P1 and P2. Therefore, the bending moment measuring device 36-1a,
When the bending moments M1 and M2 at the respective height positions are measured by using 36-1b, 36-2a and 36-2b, and these values are used to determine a regression line RL as shown in FIG.
The inclination of L with respect to the horizontal axis is the front excavation force FD. That is, the front excavation force FD is given by the following equation.

FD = (1 / L) (M1−M2) (1) Here, FIG. 4 shows each measuring device 36-1a, 36-1 on the horizontal axis.
b, the height position of 36-2a, 36-2b, and a vertical axis | shaft take bending moment value and are the graphs which plotted the measured value of each measuring device. The distance L on the horizontal axis in FIG. 4 is equivalent to the measuring instruments 36-1a and 36-1b and 36-2a and 36-in FIG.
2b, that is, the distance between the positions P1 and P2.

The bucket chain driving force FM is a torque meter 3 for measuring the axial torque of the bucket chain driving motor 33.
The following equation is obtained by using the shaft torque TM which is the measurement result of No. 4.

FM = (1 / rs) GR · TM (2) where rs is the radius of the sprocket 32 that drives the bucket chain 31, and GR is the reduction ratio of the speed reducer.

The speed vc of the bucket chain is obtained by the following equation using the rotation speed N which is the output of the tachometer 35 for measuring the rotation speed of the bucket chain drive motor 33.

Vc = (2π / GR) rs · N (3) As described above, by subtracting the front excavation resistance FD and the driving loss FR of the bucket chain from the driving force FM, the weight FL of the excavated material can be obtained. The equation holds.

FL = FM−FD−FR (4) where FL is the lifting force, which corresponds to the weight of the excavated object. The drive loss FR can be obtained by the driving force of the bucket chain during idling, or by calculating the frictional resistance between the bucket chain and the sprocket, the bending resistance of the chain connection, the resistance of the speed reducer, and the like.

If the weight FL of the excavated material is obtained, the product is multiplied by the speed vc of the bucket chain and divided by the head H of the bucket elevator 17, so that the cargo handling capacity WN is obtained. .

WN = (1 / H) FL · vc (5) Next, the relationship between the operating conditions and the cargo handling capacity will be described.
The relationship between the cargo handling capacity WH, the scraping area Au, and the excavation depth h _D was determined from the measurement results during the operation of the unloader. Methods for detecting the excavation depth, as shown in FIG. 5, determine the height h _A of up roses of excavation rear side by a longitudinal detector 50 on both sides provided a plurality each of excavation frame 18 '. This height h _A is obtained from the average value of the detection results of the detector 50 on the excavation side. Since the distance h _B between the detector 50 and the lower end of the bucket 24 is determined, the excavation depth h _D is
It is given by h _D = h _B -h _A.

FIG. 6 shows the measurement results of the relationship between WH / Au and h _D during the coal loading and FIG. 7 shows the iron ore loading. Until 0.8m excavation depth h _D bucket height, WH / Au increases linearly with increasing drilling depths h _D. WH when excavation depth h _D is larger than 0.8m
/ Au is constant. Note that 0.8 m is an example.

FIGS. 6 and 7 show that a predetermined cargo handling capacity W can be obtained by keeping the excavation depth h _D constant and adjusting the scraping area Au.

FIG. 8 shows the scraping area Au of the bucket elevator type continuous unloader performing side excavation. Since a complicated calculation is required to calculate the scraping area Au, the scraping area Au is approximated by the following equation (6).

[0037]

(Equation 1)

Here, Vt is the traversing speed of the excavated portion 18 (represented by the middle portion in the longitudinal direction), and LD is the length of the excavated portion 18. In the present invention, the cargo handling capacity is adjusted by the traversing speed Vt instead of the scraping area Au.

FIG. 1 is a block diagram of a control device for calculating the cargo handling capacity using the principle described above and performing the quantitative cargo handling based on the result and the cargo handling capacity target value WT. Output signals of the difference between the bending moment measuring instruments 36-1a and 36-1b and the difference between 36-2a and 36-2b are low-pass filters 3 for removing high-frequency components such as noise.
The noise is removed by 7-1 and 37-2, and the output signal indicating the bending moment value is supplied to the excavation resistance calculator 38. The excavation resistance calculator 38 performs regression analysis on the output signals indicating the respective bending moment values, and obtains the front excavation force FD from the slope of the regression line.

The shaft torque T which is the measurement result of the torque meter 34
M is given to a bucket chain driving force calculator 39 to calculate the bucket chain driving force FM according to the above equation (2). The rotation speed N of the bucket chain drive motor 33, which is the output result of the tachometer 35, is supplied to the chain speed calculator 40, and calculates the bucket chain speed vc according to the above equation (3). These calculation results FD, FM, vc
Is given to the cargo handling capacity calculator 41, and the above (4), (5)
The cargo handling capacity WN is calculated according to the formula.

The comparison calculator 42 compares the cargo handling capacity WN obtained by the cargo handling capacity calculator 41 with a preset cargo handling capacity target value WT and outputs a deviation. This deviation is given to the motor controller 43 and the traversing controller 44. The motor controller 43 controls the driving motor 45 of the bucket chain. The traversing controller 44 controls the traveling motor 46-1 for the traveling frame 14, the boom swing motor 46-2, the boom hoist cylinder 46-3, The bucket elevator turning motor 46-4 and the tilt cylinder 46-5 of the tilt mechanism are controlled.

Each of the motor controller 43 and the traversing controller 44 issues an operation command as follows from the deviation from the comparator 42, that is, the magnitude relation.

If WN> WT, the speed vc of the bucket chain is reduced. Further, the traversing speed Vt is reduced in order to reduce the scraping area Au.

If WN <WT, the speed vc of the bucket chain is increased. In addition, the traversing speed Vt is increased to increase the scraping area Au.

Usually, in order to obtain a predetermined cargo handling capacity, it is necessary that the excavation depth h _D is at least larger than the height of the opening of the bucket 24. The above assumes that the above conditions are met.

If the excavation depth h _D is smaller than the height of the opening of the bucket 24, first, the set excavation depth h _D
The excavation part 18 is lowered so that

With respect to the state during coal handling, numerical simulations were performed on the variation of the cargo handling capacity when the conventional control method was used and the variation of the cargo handling capacity according to the control method of the present invention. FIG. 9 shows the result of comparison between the two. The solid line indicates the case according to the proposed control method, and the broken line indicates the case according to the conventional control method. In contrast to the target value of 2200 t / H, the cargo handling capacity fluctuates from 1500 to 3000 t / H in the conventional control method, but 1800 to 2500 t / H in the proposed method.
H range. This is more effective for larger capacity, lower head machines.

[0048]

According to the present invention described above, the cargo handling capacity at the position paid out from the bucket elevator can be calculated with a small number of measurement points and a small amount of calculation, so that the cargo handling capacity can be obtained almost in real time. According to the weight FL of the excavated matter thus obtained,
By adjusting the speed vc of the bucket chain and the traversing speed of the excavation part, it is possible to realize the quantitative cargo handling.

Further, since the variation in the cargo handling capacity can be reduced, the hopper provided for absorbing the variation in the cargo handling capacity can be reduced, which is useful for reducing the weight and size of the body.

[Brief description of the drawings]

FIG. 1 is a block diagram of a quantitative cargo handling control device according to the present invention.

FIG. 2 is a diagram showing an overall configuration of a bucket elevator type continuous unloader to which the present invention is applied.

FIG. 3 is an explanatory diagram showing the bucket elevator and the excavation section shown in FIG. 2 in an enlarged manner, and showing the magnitude of a bending moment acting on different height positions of a vertical portion.

FIG. 4 is a graph showing a regression line of a bending moment for explaining a method of detecting an excavating force used in the present invention.

FIG. 5 is a diagram for explaining a method of detecting a digging depth of a bucket according to the present invention.

FIG. 6 is a diagram showing the relationship between the ratio of the cargo handling capacity and the scraping area during coal loading and the excavation depth.

FIG. 7 is a diagram showing a relationship between a ratio between a cargo handling capacity and a scraping area and an excavation depth during iron ore loading.

FIG. 8 is a diagram for explaining a scraping area by an unloader according to the present invention.

FIG. 9 is a diagram showing a result of performing a numerical simulation on a change in the cargo handling capacity when the conventional control method is used and a change in the cargo handling capacity according to the control method of the present invention.

FIG. 10 is a graph showing a predicted cargo handling capacity W obtained by a conventional method in comparison with an actual cargo handling capacity WH.

FIG. 11 is a diagram showing a relationship between a bucket chain driving force and a cargo handling capacity at the time of coal handling and iron ore cargo handling.

[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 First hydraulic cylinder mechanism 22 Hold 23 Bulk material 24 Bucket 25 Second hydraulic cylinder mechanism 26 Boom conveyor 27 Arm 31 Bucket chain 32 Sprocket 33 Bucket chain drive motor 34 Torque meter 35 Tachometer 36-1a, 36-1b, 36-2a, 36-2b
Bending moment measuring instrument 37-1, 37-2 Low-pass filter

Claims (7)

[Claims] 1. A vertical transport section hanging down at the tip of a boom, a digging section provided at a lower end of the vertical transport section, and a loose object scraped by the digging section is transported to an upper end of the vertical transport section. In a continuous unloader equipped with a bucket chain, the frontal excavation force FD and the driving loss FR of the bucket chain are subtracted from the driving force FM acting on the bucket chain to obtain the weight FL of the excavated object, and the speed FL of the bucket chain is calculated. , And dividing by the head H of the vertical transport unit to calculate a cargo handling capacity WN of the unloader. The cargo handling capacity WN is compared with a preset cargo handling capacity target value WT to calculate the cargo handling capacity WN. A method for controlling the unloading of a continuous unloader, wherein the unloader is controlled so as to reach the target cargo handling capacity value WT. 2. The fixed-quantity cargo handling control method according to claim 1, wherein the speed of the bucket chain or the traversing speed of the excavation part is controlled so that the cargo handling capacity WN becomes equal to the cargo handling capacity target value WT. Quantitative cargo handling control method for continuous unloader. 3. A vertical transport section hanging down at the tip of a boom, a digging section provided at a lower end of the vertical transport section, and a piece scraped by the digging section is transported to an upper end of the vertical transport section. In a continuous unloader provided with a bucket chain, a motor that drives a bucket chain, a torque meter that measures the torque of the motor, a tachometer that measures the number of revolutions of the motor, and different height positions of the vertical transport unit Bending mode fixed to
A digging force FD acting on the digging portion is calculated from a slope of a regression line with respect to a bending moment value obtained from the bending moment measuring device, and a measurement result of the torque meter is used. The driving force FM acting on the bucket chain is calculated, the speed vc of the bucket chain is calculated using the measurement result of the tachometer, the driving loss FR of the bucket chain is measured in advance, and these calculation results are calculated. To calculate the cargo handling capacity WN of the unloader, and compare the calculated cargo handling capacity WN with a preset cargo handling capacity target value WT so that the cargo handling capacity WN becomes the cargo handling capacity target value WT. A method of controlling a constant unloading of a continuous unloader, comprising controlling a speed of a chain or a traversing speed of the excavation part. 4. A vertical transport section hanging down at the tip of a boom, a digging section provided at a lower end of the vertical transport section, and a piece scraped by the digging section is transported to an upper end of the vertical transport section. In a continuous unloader provided with a bucket chain, a motor for driving the bucket chain, a torque meter for measuring a torque of the motor, a tachometer for measuring a rotation speed of the motor, and different heights of the vertical transport unit Bending mode fixed in position
A first calculator for calculating a digging force acting on the digging portion from a slope of a regression line with respect to a bending moment value obtained from the bending moment measuring device; and a measurement result of the torque meter. A second calculator for calculating the driving force of the bucket chain by using the following; a third calculator for calculating the speed of the bucket chain using the measurement result of the tachometer; A fourth calculator for calculating the cargo handling capacity of the unloader using the calculation result of the calculator, a comparison for calculating the calculated cargo handling capacity and a preset cargo handling capacity target value and outputting a deviation thereof; A quantitative unloading control device for a continuous unloader, comprising: an arithmetic unit; and control means for controlling an unloader so that the unloading capacity becomes the unloading capacity target value based on the deviation. 5. The quantitative cargo handling control device according to claim 4, wherein the control means controls a motor of the bucket chain based on the deviation, and a traverse speed of the excavation unit based on the deviation. And a traversing controller for controlling the unloading of the continuous unloader. 6. The quantitative cargo handling control device according to claim 4, wherein a low-pass filter for removing noise is provided between each of the moment measuring devices and the first computing device. Loading and unloading control device for continuous unloader. 7. The quantitative cargo handling control device according to claim 6, wherein the bending moment measuring devices at the respective height positions are two strain gauges arranged at the same height position, and the two strain gauges are provided. A quantitative unloading control device for a continuous unloader, wherein a front excavation force is calculated by providing a gauge before and after the vertical transport unit.