JPH0517128B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for controlling the scraping amount of a continuous unloader.

[Prior art] When unloading materials such as ore, coal, or grain continuously using a continuous unloader, it is necessary to keep the unloaded amount constant. For this reason, conventionally, a belt scale was installed on the internal conveyor of the continuous unloader. set up,
The moving speed of the bucket conveyor scraping section was controlled by the signal detected by the belt scale.

[Problems to be Solved by the Invention] However, in the case of the above-mentioned continuous unloader, the belt scale is far from the bucket conveyor, and it takes several tens of seconds for the scraped material to reach the belt scale. Therefore, even if the moving speed of the bucket conveyor scraping section was controlled by the signal from the belt scale, a time delay occurred, making it impossible to accurately control the scraping amount.

The present invention has been made in view of the above-mentioned points of view, and an object of the present invention is to provide a method for controlling the scraping amount of a continuous unloader, which enables accurate quantitative scraping when unloading scatterings from a ship's hold.

[Means for Solving the Problems] The present invention is a continuous unloader equipped with a material scraping section at the lower end of a bucket conveyor having a plurality of buckets, which detects the amount of material scraped by the buckets, and detects the amount of material scraped by the buckets. When controlling the moving speed of the material scraping unit so that the detected amount of scraping is approximately equal to the set amount of scraping, the average flow rate is calculated from the amount of unloaded cargo at a certain time interval accumulated by the belt scale, and the Compare the average flow rate and the amount of unloaded cargo at a set fixed time interval, and multiply the detected amount of load scraped by a coefficient determined based on the value obtained by the comparison to obtain the corrected amount of scraped load. The moving speed of the material scraping section is controlled so that the corrected scraping amount becomes approximately equal to the set scraping amount.

[Function] The average flow rate is calculated from the amount of unloaded cargo at each fixed time interval accumulated by the belt scale, and the average flow rate is compared with the unloaded amount at each set fixed time period to obtain a coefficient. A corrected scraping amount is calculated by multiplying the scraping amount, and the moving speed of the material scraping unit is controlled so that the corrected scraping amount becomes approximately equal to the set scraping amount. Therefore, when scraping a load, it is not affected by instantaneous fluctuations in the load, nor is it affected by detection delays due to belt scales.

[Examples] Examples of the present invention will be described below with reference to the accompanying drawings.

A continuous unloader for use in the method of the invention is shown in FIG. In the figure, reference numeral 1 denotes a traveling frame that runs on a rail 3 on which the quay wall 2 has been laid, 4 a rotating frame installed on the traveling frame 1 and capable of rotating horizontally, and 5 a rotating frame that pivots freely on the rotating frame 4. A supported boom, 6 a support frame provided at the tip of the boom 5, 7 a support frame 6
8 is a bucket conveyor disposed to pass through the swing mast 7, and 9 is a bucket conveyor 8 for carrying the materials (loads) supplied from the bucket conveyor 8. A rotary feeder 11 is a conveyor for feeding the soybeans supplied from the conveyor 10 to the external conveyor 12, and 13 is a conveyor for measuring the weight of the soybeans to be landed. Belt scale, 14 is the ship's hold.

The lower end of the bucket conveyor 8 is bent into an L-shape to form a scraping part 8a.
a can be extended and contracted back and forth by a fluid pressure cylinder 8b, and can be tilted up and down by a fluid pressure cylinder 8c, and the material scraping section 8a can be raised and lowered by a fluid pressure cylinder (not shown). It's summery.

A control block for controlling the amount of load scraped by such a continuous unloader is shown in FIG.

In the figure, 21 is a comparator that compares the set scraping amount and the actual scraping amount, 22 is a moving speed adjuster for the scraping section (see reference numeral 8a in FIG. 3), and 23 is a scattering section. 24 is a bucket scraping amount detector, 25 is an arithmetic processing unit, 26 is a moving speed control device;
27 is the scraping amount correction device, 27 is the belt scale installed on the in-machine conveyor, and 28 is the belt scale 27.
29 is a comparator that compares the set unloading amount with the average flow rate actually unloaded; 30 is a unloading amount adjuster. .

The amount of scraping with the bucket is detected using a phototube method.
There are torque methods, scraping resistance methods, and the like. For example, in the case of a phototube method, the light blocking time by a bucket is measured using a phototube, and the light blocking time is controlled to be constant. To explain this using Figure 2,
Transmission time between buckets 31 is t _po , buckets 31
And if the light shielding time by the load 32 is t _co , then t _co /t _po +t _co = t _co /T _o =t _R (constant).

When unloading, the external conveyor 12, conveyors 11 and 10, rotary feeder 9, and bucket conveyor 8 are driven, the revolving frame 4 rotates, the boom 5 rises and falls, and the unloading is performed. At this time, a speed signal V _c based on a preset scraping amount is outputted from the movement speed regulator 22 and sent to the movement speed control device 23 , and the material scraping section 8 a of the bucket conveyor 8 is controlled by the control device 23 . The materials are unloaded while moving at a predetermined speed in response to a command signal 23 from the robot. In addition, in the scraping amount detection amount 24,
In the case of the above-mentioned phototube method, the amount of scraping by the bucket 31 is detected as the ratio of the time it takes for the bucket 31 to move one pitch to the light shielding time, and the signal is sent to the arithmetic processing unit 25 and is actually processed by the arithmetic processing unit 25. The scraping amount is calculated, and the signal is sent to the comparator 21 and compared with the set scraping amount. If the set amount of scraping differs from the actual amount of scraping, a deviation signal is output from the comparator 21, and a speed signal _Vc corresponding to the deviation signal is sent to the control device 23 to scrape off the scattered material. The part 8a is accelerated or decelerated by the deviation signal, and the material scraping part 8a is adjusted so that the corrected scraping amount becomes approximately equal to the set scraping amount.
The moving speed is controlled and the scraping continues.

On the other hand, the belt scale 27 integrates the flow rate of the load that has passed through the belt scale 27, and the integrated signal is sent to the average flow rate calculation device 25, where the average flow rate Q/T is calculated at regular intervals. The flow rate signal is sent to the comparator 29, where the set unloaded amount and the calculated average flow rate are compared, and if the set unloaded amount and the calculated average flow rate are not equal, the deviation signal is compared. Unloading amount regulator 3 from container 29
0, and the unloading amount regulator 30 outputs a coefficient according to the deviation and sends it to the scraping amount correction device 26, where the calculated scraping amount sent from the arithmetic processing device 25 is output. The amount of scraping is corrected by multiplying by the amount of scraping, and the corrected amount of scraping is output to the comparator 11. If there is a difference between the corrected scraping amount and the set scraping amount, the deviation is output from the comparator 11, and the corrected scraping amount and the set scraping amount are determined in the same manner as described above. The moving speed of the picker scraper is controlled to be approximately equal.

The reason why the detected scraping amount is corrected by multiplying it by a coefficient is because the scraping amount generally fluctuates from moment to moment, and if it is used as it is as a control signal, stable control cannot be performed. Therefore, a coefficient is determined empirically depending on whether the scraping amount tends to be large, increasing or decreasing, and the detected scraping amount is corrected using this coefficient to perform stable control.

It should be noted that the present invention is not limited to the above-described embodiments, and it goes without saying that various changes can be made without departing from the gist of the present invention.

[Effects of the Invention] According to the scraping amount control method of a continuous unloader of the present invention, the average flow rate is calculated from the integrated amount at regular intervals, the average flow rate is compared with the set unloaded amount, and the difference is calculated. Since the scraping amount is corrected accordingly, it is not affected by instantaneous load fluctuations, and the scraping amount is directly detected to control the moving speed of the bucket conveyor scraping section. ,
Unaffected by detection delay due to belt scale,
Various excellent effects such as stable control can be achieved.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of the scraping amount control method of the continuous unloader of the present invention, Fig. 2 is a principle diagram of an example of how to detect the scraping amount used in the control method shown in Fig. 1, and Fig. 3 1 is a side view of a continuous unloader to which the method of the present invention is applied. In the diagram, 5 is a boom, 8 is a bucket conveyor, 8
21 is a comparator, 22 is a moving speed regulator for the scraping section, 23 is a moving speed control device for the scraping section, 24 is a scraping amount detector, 25 is an arithmetic processing unit, 26 is a scraping amount correction device, 27 is a belt scale, 28 is an average flow rate calculation device, 29 is a comparator, 30 is a load adjustment device, 31 is a bucket, 32
indicates load.

Claims (1)

[Claims] 1. In a continuous unloader equipped with a material scraping section at the lower end of a bucket conveyor having a plurality of buckets, the amount of material scraped by the buckets is detected, and the amount of material scraped by the bucket is set to the amount of material scraped. When controlling the moving speed of the material scraping unit so that it is approximately equal to the amount, the average flow rate is calculated from the amount of unloaded cargo at each fixed time period integrated with the belt scale, and the average flow rate and the amount of unloaded material at each set time interval are calculated. The corrected scraping amount is obtained by multiplying the detected scraping amount of the load by a coefficient obtained based on the value obtained by the comparison, and the corrected scraping amount is calculated based on the setting. A method for controlling the amount of scraping of a continuous unloader, comprising controlling the moving speed of the material scraping section so that the amount of scraping is substantially equal to the amount of scraping that has been done.