JPH0826492A - Control method of continuous unloader and its device - Google Patents

Abstract

PURPOSE:To fixedly retain an unloading amount per unit time from a hold or the like by detecting an error equivalent amount between the target depth and the picking in depth of a scraping portion by means of a predetermined detection cycle, administering statistical processing to a detected error equivalent amount, regulating the picking in depth. CONSTITUTION:In the case of a device in which a scraping portion supported on a land side is inserted by predetermined picking in depth (target depth) into a cargo in a hold, and scrapes out the cargo by conducting horizontal movement and carries out unloading, distance measuring devices 8, 9 are fitted to a turning mast so that respective measuring surfaces may face the scraping front upper surface of the cargo, and in the case in which a signal fed from a derricking motion control button 7 is the one to signify an ON state, at an operation device 10, measuring is conducted by means of the respective distance measuring devices 8, 9. Errors between a target distance and distances between the respective measuring surfaces and the scraping front upper surface are calculated, and in the case in which the average value of the errors calculated within a predetermined specimen period is not within a predetermined range, control is made so that the turning mast may be ascended/descended according to its average value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous unloader control method and apparatus for maintaining a constant landing amount per unit time (hereinafter referred to as "landing flow rate").

[0002]

2. Description of the Related Art An unloader is used, for example, when unloading a load of ore, coal, grain, etc. from a hold (holding part) 6 of a ship, and an example of its entire structure is shown in FIG. . The unloader shown in this figure is provided with a traveling unit 1 rotatably provided on a wharf which is a loading / unloading site, a boom 2 provided on the traveling unit 1 rotatably and vertically, and a boom 2 of the boom 2. The swinging mast 4 is rotatably supported by the top support frame 3 provided at the tip end and hangs down in the vertical direction, and the scraping portion 5 is provided at the lower end of the swinging mast 4. It

The unloader shown in this figure is generally called a chain bucket type unloader, and an endless chain to which a plurality of buckets B, B, ... Are attached moves around the upper part of the rotating mast 4 and the outer periphery of the scraping part 5. The buckets B, B, ... laid on the bottom of the scraping unit 5 scrape the cargo in the hold 6, and convey the scraped cargo to the upper part of the swivel mast 4. Then, the scraped load is unloaded via the boom 2 and the traveling unit 1. At this time, the scraping work needs to be sequentially performed from the upper layer of the cargo so that the upper surface of the cargo in the hold 6 becomes substantially horizontal.

By the way, in this type of unloader, the landing flow rate is often small with respect to the size of the hold 6 due to various circumstances, and the landing work requires an extremely long time. Therefore, there is known a continuous unloader which is controlled by the control device and automatically and continuously carries out the landing work. The control device of the continuous unloader stores the route and the like of the turning mast 4 which is manually operated in the teaching process, and hydraulically controls each part of the continuous unloader in order to reproduce the route and the like in the subsequent playback process.

The playback process by the above-mentioned continuous unloader will be described with reference to FIG. FIG. 5 is a schematic sectional view taken along the line AA ′ of FIG. 4, and in this figure, in order to avoid complication of the drawing, the sectional structure of the swiveling mast 4 is shown as a simple plane. As shown in this figure, according to the continuous unloader, the turning mast 4 moves along the pre-teached path C so as to scrape the cargoes existing in all the areas in the hold 6 on average.

FIG. 6 shows the positional relationship between the scraping section 5 and the load. FIG. 6 is a view of the scraping section 5 shown in FIG. 4 as viewed from the D direction. As shown in this figure, the scraping section 5 moves in the E direction at a predetermined speed. At that time, the buckets B, B, ...
Conveys the load scraped off by passing through the bottom of the scraping unit 5. As a result, a height difference of the distance h occurs between the upper surface of the load before being scraped (upper surface S ₁ before scraping) and the upper surface of the load after being scraped (upper surface S ₂ after scraping). To do. Hereinafter, this height difference will be referred to as a cutting depth h.

When the scraping operation for the target layer is completed and the upper surfaces of the cargo are all level with the upper surface S ₂ after scraping, for example, the tip of the boom 2 moves vertically downward and the swing mast 4 is moved. And the scraping part 5 moves vertically downward by the cutting depth h. Of course, the moving operation at this time is also taught in advance. Thus, the cargo in the hold 6
It is scraped off one by one from the upper layer.

As described above, according to the continuous unloader, while the upper surface of the cargo in the hold 6 is made substantially horizontal, the cargo is discharged so that the landing flow rate becomes substantially constant (according to the cutting depth h). It can be scraped automatically. It is extremely important to make the landing discharge almost constant in order to omit or simplify the subsequent process on land, and the measurement of the landing discharge can be performed, for example, in the vicinity of the cargo passage of the traveling unit 1. It is performed by the provided sensor.

[0009]

By the way, since the ship loaded with the cargo is on the sea, the position of the hold 6 is the highest at high tide and the lowest at low tide. That is, the position of the hold 6 fluctuates in the vertical direction according to the ebb and flow of the tide. On the other hand, since the continuous unloader is installed on land, the positions of the turning mast 4 and the scraping unit 5 do not depend on the ebb and flow of the tide. Therefore, the positional relationship between the scraping unit 5 and the pre-scraping upper surface S ₁ changes according to the ebb and flow of the tide, and the cutting depth h changes. If the cutting depth h changes, there is a problem that the amount of cargo scraped by the buckets B, B, ... Per unit time, that is, the landing flow rate changes.

In order to avoid this problem, it is necessary to correct the positions of the swiveling mast 4 and the scraping portion 5 in accordance with the vertical movement of the hold 6 to make the cutting depth h constant. As one of the correction methods, feedback control of the drive system is performed based on the landing flow rate measured by a sensor provided in the vicinity of the traveling unit 1, and the continuous unloader units (for example, It is also conceivable to activate the boom 2).

By the way, in the continuous unloader, the scraping unit 5
In some cases, the time required for the cargo scraped off by the time to reach the above-ground part 1 may be more than sufficient. Therefore, even if the drive system is feedback-controlled according to the landing flow rate detected by the sensor installed near the traveling unit 1, the control delay becomes large, and in some cases, the landing flow rate may further vary. is there. The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a control method for a continuous unloader and a device therefor capable of keeping the landing flow rate constant.

[0012]

The invention according to claim 1 or 2 is characterized in that a scraping section supported on the land side so as to be movable in the horizontal direction and the vertical direction is provided on the vessel. A method of controlling a continuous unloader for scraping a cargo in the hold and landing it while inserting a target depth which is a preset cutting depth into a cargo inside and moving the cargo horizontally. A detection step of detecting an error equivalent amount between the cutting depth of the cut portion and the target depth in a predetermined detection cycle, and a statistical process is performed on the error equivalent amount detected in the detection step within a predetermined sampling period, And an adjusting step of adjusting the cutting depth based on a statistical value such as an average value obtained by statistical processing. Further, in the invention according to claim 3 or 4, the scraping portion supported on the land side so as to be movable in the horizontal direction and the vertical direction is set in advance during loading in a hold provided on the ship. A device for controlling a continuous unloader for scraping a cargo in the cargo hold and landing it while inserting the target depth which is the cut depth and moving in the horizontal direction. A distance measuring device which is attached to the scraping unit or a means for supporting the scraping unit so as to face the upper surface of the cargo in the hold, and which detects the distance between the measurement surface and the upper surface in a predetermined detection cycle; An error between the distance detected by the distance measuring device and a preset target distance was calculated as an error equivalent amount between the cutting depth of the scraping unit and the target depth, and was calculated within a predetermined sampling period. The error Subjected to statistical processing to equivalents,
A scraping unit for outputting a signal for adjusting the cutting depth based on a statistical value such as an average value obtained by the statistical processing, and the scraping unit according to a signal output from the computing device. It is characterized by raising and lowering.

[0013]

According to the method of the first or second aspect, in the detecting step, the error equivalent amount between the cutting depth of the scraping portion and the preset target depth is detected in a predetermined detecting cycle. Further, in the adjusting step, statistical processing is performed on the error equivalent amount detected in the detecting step within a predetermined sampling period, and the cutting depth is adjusted based on a statistical value such as an average value obtained by the statistical processing. To do. Therefore, the cutting depth is adjusted according to the average fluctuation within the sampling period, not the temporary vertical movement. Further, the cutting depth of the scraping section becomes constant, and the landing flow rate according to the cutting depth becomes constant. Further, according to the apparatus of any one of claims 3 and 4, the distance measuring device attached to the scraping section or the means for supporting the scraping section is the cargo hold just before being scraped from the measurement surface. The distance to the upper surface of the cargo inside is detected in a predetermined detection cycle. In addition, the arithmetic unit
An error between the distance detected by the distance measuring device and a preset target distance is calculated as an error equivalent amount between the cutting depth of the scraping unit and the preset target depth. Further, the arithmetic device performs statistical processing on the error equivalent amount calculated within a predetermined sampling period, and a signal for adjusting the cutting depth based on a statistical value such as an average value obtained by the statistical processing. Is output. That is, the cutting depth is adjusted according to an average fluctuation within the sampling period, not a temporary vertical movement. Then, the scraping unit moves up and down according to the signal output from the arithmetic unit. In this way, the cutting depth of the scraping section becomes constant, and the landing flow rate according to the cutting depth becomes constant.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a partial configuration of a control device 12 of a continuous unloader according to an embodiment of the present invention. The control device 12 shown in this figure has all the functions of a conventional control device. In FIG. 1, reference numeral 7 denotes an undulation correction button (for instructing whether to perform correction or not) which is changed from an on state to an off state or from an off state to an on state by being pressed by an operator. It outputs a signal according to the status.

Reference numerals 8 and 9 denote distance measuring devices such as ultrasonic sensors, which are formed at the lower end of the swivel mast 4 so that the respective measurement surfaces 8a and 9a face the pre-scraping upper surface S ₁ as shown in FIG. It is attached to the side surface of the projected portion 4a. These measuring devices 8 and 9 are arranged at a predetermined distance from each other, and each measuring surface 8
The distances L ₁₈ and L ₁₉ between the a and 9a and the upper surface S ₁ before scraping are measured, and the measured signals corresponding to the distances L ₁₈ and L ₁₉ are output.

Referring again to FIG. 1, reference numeral 10 denotes an arithmetic device for performing a predetermined arithmetic processing (described later) according to the signal output from the undulation correction button 7 and each signal under measurement, and control according to the arithmetic result. Output a signal. Reference numeral 11 denotes a hydraulic pump unit that operates according to a control signal supplied from the control device 12, and controls the hydraulic motors M, M, ...

The arithmetic unit 10 includes a CPU, RO (not shown).
It consists of M, RAM, and various I / O interfaces.
In the playback process, the undulation control program stored in the ROM is executed to output a control signal so that the landing flow rate becomes constant. Here, the processing performed by the arithmetic unit 10 that executes the undulation control program will be described with reference to FIGS.

FIG. 3 is a flow chart showing the flow of processing of the undulation control program. Since each processing shown in this figure is executed by the arithmetic unit 10, hereinafter, unless otherwise specified, the main body of processing is the arithmetic unit 10. To do. Prior to the processing shown in this figure, the RAM of the arithmetic unit 10 is initialized.
Then, the distance between the pre-scraping upper surface S ₁ at the start of the playback process and the measurement surfaces 8a, 9a of the distance measuring devices 8, 9 is obtained, and the target distance L ₀ (FIG. 2), which is the average value of these distances. Is stored at a predetermined address in the RAM.

When the scraping unit 5 starts moving in the E direction (see FIG. 2), the arithmetic unit 10 activates the undulation control program and executes the process of step S1 in FIG. In step S1, it is determined whether or not the undulation correction button 7 is supplied with a signal indicating the ON state. This judgment result is "N
If "O", the process ends, and if "YES", the process proceeds to step S2. In step S2, the distance measuring device 8,
A predetermined filter is applied to each signal under measurement supplied from No. 9, and each error between each distance L ₁₈ and L ₁₉ represented in each output obtained and a preset target distance L ₀ is calculated. Each of these errors is also an amount corresponding to the error between the target depth CL, which is an ideal cutting depth preset according to the target distance L ₀ , and the actual cutting depth h.
This is referred to as "the amount of error".

Then, from the calculated respective error equivalent amounts, the average value thereof is stored in the write address of the RAM as the average error equivalent amount ΔL ₈₉ . Here, the write address is one of a plurality of (for example, six) preset addresses, and the calculated latest average error equivalent amount ΔL.
₈₉ is written to one of the write addresses with the oldest update time.

Next, in step S3, the average error equivalent amounts ΔL ₈₉ , ΔL ₈₉ , written in the plurality of write addresses,
The average value of ... Is obtained. Here, for example, six average error equivalent amounts ΔL ₈₉ stored in each write address of the RAM are read (the contents of the addresses where the average error equivalent amount ΔL ₈₉ was not written remain initialized to 0), The average value AVR of them is calculated. Next, in step S4, it is determined whether or not the absolute value of the average value AVR is greater than or equal to a predetermined threshold value ΔL _S (for example, 100 mm). If the determination result is “NO”, the process proceeds to step S5.

In step S5, a time waiting is performed (waiting time is variable). Then, after the waiting time has elapsed, the process returns to step S2. The waiting time in step S5 is set so that the process in step S2 is performed in a predetermined detection cycle (for example, 1 minute interval). After that, the processes of steps S2, S3, S4, and S5 are repeatedly performed until the determination result of step S4 becomes “YES”. The absolute value of the average value AVR is the threshold Δ
It becomes L _S or more, and the judgment result in step S4 is “YE
If "S", the process proceeds to step S6.

In step S6, it is determined whether the average value AVR is 0 or more. This judgment result is "YES"
If so, go to step S7. If "NO", go to step S7.
The process proceeds to 8. In step S7, a signal for lowering the scraping unit 5 by, for example, 50 mm is supplied to the hydraulic pump unit 11. Further, in step S8, the scraping unit 5
Is supplied to the hydraulic pump unit 11 by, for example, increasing 50 mm. These steps S7, S8
When is completed, the process returns to step S1. The above-described processing is continued until the undulation correction button 7 is turned off, but when the layer on which the scraping work is performed shifts from the upper layer to the lower layer, the contents of each write address in the RAM are cleared and the step is performed again. The process is started from S1.

The playback process performed by the continuous unloader in such a configuration will be described with reference to FIG. In the playback process, the continuous unloader is controlled so that the cutting depth h matches the target depth CL, and the scraping operation for the layer of the load to be scraped is started. When the scraping work is started, the detection process and the adjustment process are started in parallel.

In the detection step, the average error equivalent amount ΔL ₈₉ is calculated in a predetermined detection cycle and stored in each write address of the RAM. On the other hand, in the adjustment step, when the average error equivalent amount ΔL ₈₉ becomes a value equal to or larger than the predetermined threshold value ΔL _S, the six average error equivalent amounts ΔL calculated in the last 5 minutes.
The average value AVR of ₈₉ , ΔL ₈₉ , ... Is calculated, and the scraping unit 5 is moved up and down based on this average value AVR.

While the above-mentioned detection process and adjustment process are being executed in parallel, if the hold 6 swings in the vertical direction depending on the state of the sea surface or the ebb and flow of the tide, the actual cutting depth h
The average error equivalent amount ΔL ₈₉ between the target depth CL and the target depth CL becomes a value equal to or larger than a predetermined threshold value ΔL _S. If such a state continues for a predetermined period, the absolute value of the average value AVR of the average error equivalent amounts ΔL ₈₉ , ΔL ₈₉ , ... Stored at each write address becomes a value equal to or greater than the threshold value ΔL _S.

In such a state, when the average value AVR is 0 or more, it is determined that the tide is low and the scraping unit 5
Is controlled to fall by 50 mm. On the contrary, when the average value AVR is less than 0, it is determined that the tide is rising and the scraping unit 5 sets
It is controlled to rise by 0 mm. As a result, the scraping unit 5 moves up and down so that the actual cutting depth h substantially matches the target depth CL, and the landing flow rate becomes substantially constant.

As explained above, according to one embodiment of the present invention, the actual depth of cut h is made to substantially coincide with the target depth CL and the landing flow rate is made almost equal without being affected by the ebb and flow of the tide. It can be constant. Further, the distance measuring devices 8 and 9 are provided at a predetermined distance from each other, and the measurement surfaces 8a and 9a and the pre-scraping upper surface S ₁
Since the average error equivalent amount ΔL ₈₉ is calculated from each error between the respective distances L ₁₈ and L ₁₉ and the target distance L ₀ and used for the calculation process of the average value AVR, the measurement error can be made small. it can. In addition, each distance L ₁₈ , L _{19 in} a predetermined detection cycle.
Was measured and the average value AVR calculated according to the respective distances L ₁₈ and L ₁₉ measured during the sample period was compared with the threshold value ΔL _S , so that an error due to a temporary change in sea surface condition, etc. Control can be prevented.

In the above embodiment, the distance measuring devices 8 and 9 are used, but three or more distance measuring devices may be used. The distance measuring devices 8 and 9 may be installed on the ground side as long as they can measure the distance in the vertical direction from the upper surface S ₁ before scraping. Furthermore, when the tide is high or low, the scraping unit 5 is kept at a certain distance (50 m).
Although the example in which the height is raised and lowered by m) is shown, the vertical distance may be determined according to the average value AVR.

In the above-described embodiment, the average value AVR calculated based on the distances L ₁₈ and L ₁₉ measured during the sampling period is compared with the threshold value ΔL _S, and the result is determined according to the result. Although the scraping unit 5 is moved up and down by the above, the present invention is not limited to this, and a known statistical method is applied to each of the distances L ₁₈ and L ₁₉ measured within the sample period, and the average value obtained by this is applied. The scraping unit 5 may be moved up and down based on statistical values other than the above.

[0031]

As described above, according to the present invention,
The amount of error between the cutting depth of the scraping unit and the preset target depth is detected in a predetermined detection cycle, and statistical processing is performed on the amount of error detected within a predetermined sampling period, and the statistical processing is performed. The cutting depth is adjusted based on the statistical value such as the average value obtained by. That is, the cutting depth of the scraping portion becomes constant. Therefore, there is an effect that the landing flow rate can be made constant according to the cutting depth.

[Brief description of drawings]

FIG. 1 is a block diagram showing a partial configuration of a control device 12 of a continuous unloader according to an embodiment of the present invention.

FIG. 2 is a diagram for explaining an operation of the control device 12.

FIG. 3 is a flowchart showing a processing flow of an undulation control program.

FIG. 4 is a diagram showing an overall configuration of a conventional continuous unloader.

FIG. 5 is a diagram for explaining the operation of a conventional continuous unloader.

FIG. 6 is a diagram for explaining the operation of a conventional continuous unloader.

[Explanation of symbols]

 7 Undulation correction button 8,9 Distance measuring device 8a, 9a Measuring surface 10 Computing device 12 Control device

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shoji Hamaya 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Nihon Kokan KK (72) Inventor Toru Hayashi 1-19-10, Mori, Koto-ku, Tokyo Ishikawajima Harima Heavy Industries Ltd. Koto Office

Claims (4)

[Claims] 1. A target depth, which is a cutting depth preset for a scraping portion supported on the land side so as to be freely movable in a horizontal direction and a vertical direction, during loading in a hold provided on a ship. A method of controlling a continuous unloader that scrapes the cargo in the hold and unloads it while moving it in the horizontal direction only by inserting a predetermined amount of error between the cutting depth of the scraping unit and the target depth. A detection step of detecting in a detection cycle, and statistical processing is performed on the error equivalent amount detected in the detection step within a predetermined sampling period, and the cutting depth is adjusted based on the statistical value obtained by the statistical processing. A method for controlling a continuous unloader, comprising: an adjusting step. 2. The control method for a continuous unloader according to claim 1, wherein the statistical process is a process for obtaining an average value. 3. A target depth, which is a cutting depth set in advance in a cargo in a hold provided on a ship, with a scraping portion supported on the land side so as to be movable in a horizontal direction and a vertical direction. It is a device that controls a continuous unloader that scrapes the cargo in the hold and unloaded it while moving horizontally only by inserting it so that it faces the upper surface of the load in the hold just before the measurement surface is scraped. A distance measuring device that is attached to the scraping unit or a unit that supports the scraping unit and that detects a distance between the measurement surface and the upper surface in a predetermined detection cycle; and the distance detected by the distance measuring device. While calculating an error with a preset target distance as an error equivalent amount between the cutting depth of the scraping unit and the target depth, statistically processing the error equivalent amount calculated within a predetermined sampling period, The statistics department And an arithmetic unit for outputting a signal for adjusting the cutting depth based on a statistical value obtained by, and moving the scraping unit up and down according to a signal output from the arithmetic unit. Control device for continuous unloader. 4. The control device for a continuous unloader according to claim 3, wherein the statistical process is a process for obtaining an average value.