JPH0354741B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Technical Field] The present invention relates to a dredging control method for a dredger that determines the soil quality of the submerged soil to be excavated by a dredger and adjusts the swing speed according to the soil quality determination result. .

[Conventional technology]

This type of dredger is used to secure water depth for navigation routes, ports, etc. by scraping away the submerged soil such as riverbeds or seabeds, or to remove sludge, etc. This is becoming an important issue. The reason for this is that if a ladder with a bucket or cutter is used to scrape away the soil, for example, if it is forced to move forward even though it has hit a hard soil slab, the efficiency of the dredging work will be significantly reduced. This is because the dredging work may have to be temporarily halted due to damage to the bucket.

Therefore, in recent years, as a dredging control method for dredgers,
A dredging control method has been proposed in which the armature current of the DC motor on the swing control side is controlled based on a field current value so that the output torque of the DC motor on the swing control side becomes equal to the set torque.

[Problem that the invention seeks to solve]

However, this method is directly affected by the difference between the swing speed of the dredger and the winding/feeding speed of the winch, and dredging is controlled at the optimal swing speed (traveling speed) according to changes in soil thickness, soil quality, etc. I have a problem that I can't do.

The present invention has been made with attention to the above points, and an object of the present invention is to provide a dredging control method for a dredger that can accurately perform dredging work at a swing speed that is more responsive to changes in soil quality.

[Means for solving problems]

In a dredger that excavates underwater soil, the present invention detects one or more of vibrations of the hull, heel, and load current of a bucket or cut drive source to determine the soil quality of the soil, and determines the soil quality. a swing speed correction means for obtaining a correction swing speed value by adding or subtracting a correction swing speed from the current swing speed of the dredger according to the result; and a speed comparison output means for comparing with a standard swing speed obtained in advance and outputting the corrected swing speed if the added corrected swing speed is small, and the standard swing speed if it is large, and this speed comparison output The swing speed is controlled using the output of the means and the subtractively corrected swing speed.

[Effect]

Therefore, by taking the above measures,
The soil quality of the soil bed is accurately determined and the swing speed is adjusted based on the result of this determination while giving a predetermined relatively small correction speed to the current swing speed of the dredger, so it is possible to adjust the swing speed sufficiently to respond to changes in soil quality. This allows dredging control to be performed at a precise swing speed.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1 to 6. First, in a bucket dredger with a bucket rudder, as shown in Figs. The rudder 2 is installed so that the tip of the rudder 2 is in contact with the bottom 3 of the water. 4 is a bucket drive source, and 5 is a rudder support. Although the rudder 2 is not shown, a rudder lifting device is installed on the bow side of the ship, and the rudder 2 is moved up and down by suspending a relatively forward end thereof. Therefore, with such a configuration, by driving the bucket drive source 4, the tumbler shaft 2b is rotated, and the bucket shaft 2a is rotated accordingly, and the bucket shaft 2a at the lowest end of the rudder removes the earth and sand on the water bottom 3. etc. will be removed and dredged.

In addition, in this dredger, wires or chains 6A1 to 6A3, 6B are anchored in three directions from the bow side A and the bow side B of the hull 1, respectively.
1 to 6B3 are strung, each chain etc. 6A1 on board the ship.
~6A3, 6B1~6B3 each have a winch 7...
It is wound so that it can be wound up or unwound. In these chains, 6A1 is designated as the bow left line, 6A2 is the head line, 6A3 is the bow right line, 6B1 is the stern left line, 6B2 is the stern line, and 6B3 is the stern right line. Therefore,
The bucket dredger has 6 lines stretched in each direction.
It is reliably positioned at a predetermined position by A1 to 6A3 and 6B1 to 6B3. Usually, when the hull 1 is moved during dredging, the bow left line 6A1 and the stern left line 6B3 are fed out while the lines 6A3,
By winding up the head line 6B3, the swing motion 8 shown in FIG.
Bake is applied to A2, stun line 6B
2 is unrolled or wound up as appropriate. Furthermore, the forward motion 9 shown in FIG. 3 is performed by winding up the head line 6A2 and the like while letting out the stun line 6B2 and the like. In this way, the earth and sand etc. on the water bottom 3 are dredged, and the dredger then dredges the earth and sand over the section 10 while drawing an arcuate trajectory while repeating the swing motion 8 and forward motion 9 as shown in Fig. 3. It is. During this time, Bucket 2a
The earth and sand inside is loaded onto an earth carrier or the like and transported by a belt conveyor 11 in the center of the hull 1.

By the way, bucket dredgers have the characteristic of being able to dredge even relatively hard soil, but this has been an obstacle to automating dredging work.

Therefore, in the present invention, a swing speed control means shown in FIG. 4 is provided in the dredger as described above, and dredging is performed at a swing speed corresponding to changes in soil quality based on the operation shown in FIG. 5. First, in FIG. 4, reference numeral 21 denotes soil quality determination means, to which a soil quality detection signal is inputted, for example, from one or more of a vibration detector, a heel detector, and a load current detection device of a ladder drive source. It's becoming like that. The vibration detector used is one that has been commonly used in the past. That is, when the bucket 2a collides with a hard soil slab or a clay slab during dredging, the entire ladder 2 generates vibrations, which are detected by a vibration detector and the vibration detection signal is used as a soil quality detection signal to be used as a soil quality determination means. 21. Further, the heel detector detects the heel in the swing direction of the dredger during the swing motion 8, that is, the inclination of the left and right sides of the hull 1. Various types of heel detectors can be considered, for example, the movement of a gyroscope. A potentiometer is used to detect this, the moving state of bubbles in a bubble tube is detected optically, or a dredging vessel is provided with water gauges on both sides of the dredger, and the output chains of these water gauges are detected. Further, the load current detection device detects the load current of the bucket rotary motor, which is the bucket drive source 4. That is, the bucket cart 2a is rotating at a predetermined rotation speed during dredging, but when the bucket cart 2a hits a hard soil slab or a clay slab, the load current of the motor increases and the torque of the motor increases rapidly. Therefore, this load current is detected by a load current detection device and is supplied to the soil quality determination means 21 as a soil quality detection signal. The soil quality determining means 21 receives the soil quality detection signal and switches the switches 22 and 23 to the opposite side from the illustrated position when the detected value exceeds a predetermined upper limit, that is, when the soil is hard, clay, etc. Control. 24 is a subtraction operation section, 25 is an addition operation section, and these are, for example, the right line 6A.
Current swing speed signal obtained from the tacho generator etc. installed on the winch 7 that winds up 3,6B3
Sv and a predetermined relatively small correction swing speed signal ΔS are input to each calculation unit 2.
In steps 4 and 25, the swing speed is corrected by subtraction and addition, respectively. Reference numeral 26 denotes a speed comparison output means for comparing the output of the addition calculation section 25 with the standard swing speed from the standard swing speed calculation section 27 when the switches 22 and 23 are in the positions shown in the figure. If the swing speed is determined to be high, a standard swing speed signal is output, and if the swing speed is determined to be low, a modified swing speed signal is output. Note that the standard swing speed calculating section 27 calculates the standard swing speed as follows. In other words, as shown in Fig. 6, when swinging at the maximum swing speed Smax at the thinnest part of the soil (water depth at the highest point) Dmin (y) within the range of swing width W (m), the predetermined amount of dredged soil is
The target advance amount Ls is determined based on the formula below so that Vs (=Cs×Ns) is obtained. However, upper and lower limits shall be set. Cs is the target volume of soil in the bucket, and Ns is the bucket speed (pieces/min).

Vs=Smax・Ls(Dmin(y)−Ds) ……(1) Therefore, from the above formula, the target advance amount Ls is: Ls=(Cs×Ns)/{Smax・(Dmin(y)−Ds) } ...(2) becomes. However, in the above equation, Ds is the dredging target depth, and Smax can be considered to be fixed. Then, the target advance amount obtained as above
In addition to Ls, using Vs, water depth D (x, y), Ds, etc., the amount of dredged soil is constant regardless of the soil thickness at that time.
The standard swing speed Ss is determined based on the formula below so as to ensure Vs, and is supplied to the speed comparison output means 26. However, upper and lower limits shall be set.

Vs=Ss・(D(x,y)−Ds)・Ls……(3) Ss=Vs/{(D(x,y)−Ds)・Ls}……(4) In Fig. 4, 28 is Each winch speed calculation section 29 calculates the speed of each winch, and 29 is a winch drive control section that controls the winch 7 that winds/feeds out the line based on the output of the winch speed calculation section 28. The winch speed is controlled.

Next, swing speed control will be explained with reference to FIG. First, as shown in steps S1 to S3, the soil quality determination means 21 determines whether or not the detection values detected by the vibration detector, heel detector, and load current detection device exceed the upper limit values determined respectively. If either of them exceeds the upper limit, that is, if the soil is hard, for example, the switches 22 and 23 are closed to the opposite side from the illustrated position, and the subtraction operation section 2
The judgment result is sent to 4. Here, the subtraction calculation unit 24
As shown in step S4, the correction swing speed ΔS is subtracted from the current swing speed Sv of the dredger 1 to lower the swing speed, and this is supplied to each winch speed calculating section 28. The winch speed calculation section 28 determines the winding speed and payout speed of each winch 7 based on the subtracted and corrected swing speed, and supplies the results to the winch speed control section 29, thereby swinging the dredger 1 at a swing speed corresponding to the soil quality. This is to control dredging in the direction.

On the other hand, if the detected value in steps S1 to S3 is below the upper limit, it is determined that the soil is soft, and the determination result is supplied to the addition calculation section 25.
The addition calculation unit 25 adds the correction swing speed ΔS to the current swing speed Sv to add and correct the swing speed, and supplies this to the speed comparison output means 26, as shown in step S5. This speed comparison output means 26 compares the added and corrected swing speed with the aforementioned standard swing speed Ss.
6) If the standard swing speed is large, the corrected swing speed is supplied to each winch speed calculation unit 28, and conversely, if the corrected swing speed is large, the standard swing speed Ss is supplied to each winch speed calculation unit 28 in step S7. The swing speed is adjusted so as to approach the standard swing speed without exceeding the standard swing speed.

Therefore, according to the configuration of the embodiment as described above,
Since the soil quality is determined by using one or more soil quality detectors and supplying the detected values to the soil quality determination means 21, the soil quality can be determined accurately, and depending on the soil quality determination result, for example, in the case of hard soil. Currently, the swing speed is controlled by subtracting a relatively small corrective swing speed from the swing speed.
Problems that could damage the bucket are eliminated, and dredging work can be carried out smoothly. In addition, if it is determined that the soil is soft, the swing speed is determined by adding and correcting the current swing speed by the correction swing speed, and if it is smaller than the predetermined standard swing speed, the swing speed is controlled using the corrected swing speed. In the opposite case, the swing speed is controlled at the standard swing speed, so the dredging work can be carried out smoothly and the target soil volume can be reliably excavated.

In the above embodiment, the same correction swing speed ΔS is supplied to the subtraction calculation unit 24 and addition calculation unit 25, but different values may be used. Further, the standard swing speed calculation means is not limited to the embodiment. Further, although the above embodiment uses the ladder 2 with a bucket, a ladder with a hook may be used instead. Furthermore, soil quality determination means 21
If the signal is converted into a binary logical signal and output, the switches 22 and 23 can be made unnecessary. Also,
By outputting a binary signal or a positive/negative signal from the soil quality determination means 21, both the calculation units 24 and 25 can be combined into one and perform the same function.
In addition, the present invention is not limited to the above embodiments, and can be implemented with various modifications.

〔Effect of the invention〕

As detailed above, according to the present invention, the dredger can dredge earth and sand by swinging the dredger at an appropriate swing speed depending on the soil quality, and can smoothly perform dredging work without damaging the bucket or the like. A dredging control method can be provided.

[Brief explanation of drawings]

Figures 1 to 6 are shown to explain one embodiment of the present invention, and Figure 1 is a schematic diagram showing a dredging state, Figure 2 is a plan view during dredging, and Figure 3 is a diagram showing a dredging state. 4 is a schematic block diagram for realizing the method of the present invention, FIG. 5 is an explanatory diagram of swing control operation, and FIG. 6 is an explanation for determining the standard swing speed. It is a diagram. 1... Hull, 2... Rudder, 2a... Bucket, 4... Bucket drive source, 6A1 to 6A3, 6
B1-6B3...Line of chain etc., 7...Winch, 21...Soil quality determination means, 24...Subtraction operation section, 25...Addition operation section, 26...Speed comparison output means, 27...Standard swing speed Arithmetic unit, 28...
...Each winch speed calculation unit, 29...Winch drive control unit.

Claims (1)

[Claims] 1. In a dredger that excavates underwater soil, it is possible to determine whether the soil is hard or clay based on one or more signals of vibration of the ship, heel and load current of the bucket or cutter drive source. soil quality determining means for determining whether the soil type belongs to the soil type; and when the soil type determining means determines that the soil type belongs to hard soil or clay type, deceleration correction is performed by subtracting a correction swing speed from the current swing speed of the dredger. swing speed deceleration correction means for obtaining a swing speed; and swing speed acceleration correction for obtaining an accelerated correction swing speed by adding a correction swing speed to the current swing speed when the soil quality is determined to be soft soil by the soil quality determination means. The accelerated corrected swing speed that has been added and corrected by the swing speed acceleration correcting means is compared with the predetermined standard swing speed, and if the accelerated corrected swing speed is small, the accelerated corrected swing speed is increased. and speed comparison output means for respectively outputting the standard swing speeds, and the swing speed is decelerated by the swing speed deceleration correction means or by the speed comparison output means according to changes in the soil quality of the underwater bed. A dredging control method for a dredger, characterized in that the current swing speed is adjusted using the obtained output.