JPH0321687B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a swing braking device for a cutter suction pump type dredger.

[Conventional technology]

Figures 1 and 2 are an explanatory plan view and side view of a cutter suction pump dredger, and Figure 3 is a front view of the cutter seen from the rudder side. 1 is the hull of the dredger, and 2 is the hull 1. Rudder installed at the bow, 3
is a cutter attached to the tip of the rudder 2 and excavates earth and sand from the seabed ground 11 by its rotation; 4 is a spud installed at the stern of the hull 1; 5 and 6 are swing winches on the starboard and port sides; 7 and 8 are swing winches on the port and starboard sides; Right and left anchors 9 and 10 anchored on the submarine ground 11
and the right and left swing wires stretched between the swing winches 5 and 6, 12 the unexcavated ground,
Reference numeral 13 indicates an arrow indicating the direction of rotation of the cutter, and reference numeral 14 indicates an arrow indicating the direction of movement of the cutter when swinging to the right. For example, when dredging in the right direction, the right swing winch 5 is operated for retracting, and the left swing winch 6 is operated for unwinding. and wind up the right swing wire 7,
The left swing wire 8 is unwound, and the cutter 3 rotates in the direction shown by the arrow 13 to cut the unexcavated ground 1.
While excavating the earth and sand 2, the robot moves to the right, in the direction of the arrow 14, centering on the spud 4.

During normal operation, this moving speed is determined by the rotational speed of the winding side swing winch, and the unwinding swing winch unwinds the unwinding wire by the amount of wire wound by the winding side swing winch. It is driven while being given an appropriate amount of braking force.

If the soil of the ground 11 is hard and the cutter 3 cannot excavate, if the rotation direction 13 and the movement direction 14 of the cutter 3 are the same as shown in FIG. The cutter begins to roll up, and the cutter movement speed at this time considerably exceeds the normal operating speed controlled by the swing winch. This phenomenon is called cutter rolling, and at this time, the winding-side swing wire becomes slack, and accidents often occur in which the slack winding-side swing wire is cut by the cutter.

In order to prevent this cutter from rolling, conventional methods utilize the phenomenon that the swing load on the winding side decreases as the swing wire on the winding side becomes slack, and apply a braking force that is inversely proportional to the increase or decrease in the swing winch load signal on the winding side. I try to give it to the exit swing winch.

[Problem to be solved by the invention]

However, the above braking force is within the range of increase/decrease of the swing winch load signal on the retraction side,
Such braking force alone may not provide a sufficient braking effect, and the phenomenon of loosening of the winding-side swing wire may continue. At this time, the hull 1 is in an unrestrained state where it is floating, and the tension of both the right and left swing wires is close to zero, and therefore the swing winch load signal on the retraction side and the swing winch load signal on the unwinding side are The difference becomes extremely small, and the smaller this value is, the more likely it is that accidents such as wire breakage may occur.

The present invention seeks to eliminate the above-mentioned drawbacks.

[Means to solve the problem]

In the dredger swing braking device of the present invention, it is possible to detect early when the cutter 3 is rolling on the seabed surface or when the winding-side swing wire begins to loosen, so that it can detect signs of rolling and prevent rolling. The progress of rolling, such as enlargement and signs of trouble due to rolling, is detected separately, and braking force is applied to the unwinding side swing winch according to each situation.

In other words, if we divide the process from the occurrence of cutter rolling until just before trouble occurs, there are four stages: before rolling occurs, rolling occurs, rolling increases (the cutter rolls faster), and before rolling trouble (wire cutting) occurs. However, in the present invention, focusing on the fact that the magnitude of each load on the swing and wire is different in each of the above stages, these are detected by the load signals of the swing and cutter, and
To apply an appropriate amount of braking force to an unwinding winch according to each stage.

Regarding the above four stages of detection, first, in the stage before rolling occurs, the cutter 3 enters excavation of hard soil, so the cutter load and the swing winch load on the winding side increase, and then the cutter 3 When the cutter begins to roll and rolling occurs, the cutter load increases compared to that during digging, and when the cutter rolling phenomenon continues, the winding side swing wire becomes slack, so the winding side swing load decreases. When rolling expands, the cutter load further increases and the swing winch load on the winding side further decreases.

At this time, if sufficient braking force is not applied to the unwinding side swing, the unwinding side swing wire will become slack and the hull 1 will float up into an unrestrained state, and the tension of both the right and left swing wires will be close to zero. Therefore, the difference between the swing winch load signal on the reeling side and the swing winch load signal on the unwinding side becomes very small. It is regarded as a pre-occurrence stage.

The present invention is a swing braking device for a cutter suction pump type dredger that has an automatic braking mechanism for a swing winch, and is applied when the load signal of the swing winch on the engulfing side increases and then the cutter load signal increases, or when the swing winch on the engulfing side increases. When the winch load signal decreases and the cutter load signal increases, a first braking signal that is inversely proportional to the increase or decrease in the load signal of the retraction side swing winch is applied to the unwinding side swing winch, and a first braking signal is applied to the retraction side swing winch. When the load signal decreases and the difference between the load signal of the retraction side swing winch and the load signal of the unwinding side swing winch decreases to a set value or more, a second The present invention is characterized in that the braking signal is applied to the unwinding side swing winch.

[Effect]

In the swing braking device for a dredger of the present invention, the load signal of the swing winch and the cutter load signal are detected, and when the cutter rolls, the first braking is applied to the swing winch on the unwinding side, and when the rolling increases, the second braking is applied. braking will be applied.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

In the present invention, when the retraction side swing winch load signal a ₁ increases from the first setting value and the cutter load signal a ₂ increases from the second setting value, and when the retraction side swing winch load signal a ₁ increases from the first setting value, 4th or 5th
a first braking signal that is inversely proportional to the increase or decrease in the winding side swing winch load signal a ₁ when the cutter load signal a ₂ increases above the third or sixth setting value. e ₁ is applied to the unwinding side swing winch, and the retracting side swing winch load signal a ₁ continues to decrease and decreases below the seventh set value.
When the difference between a ₁ and the unwinding side swing winch load signal a ₃ becomes smaller than the 8th set value, a second braking signal e ₂ that is inversely proportional to the decrease in the unwinding side swing winch load signal is applied. , is applied to the unwinding side swing winch in addition to the first braking signal _e1 .

For this reason, in the present invention, as shown in _FIG . The signals c 1 exceeding b 1 are compared with the first, fourth, fifth and seventh set values b ₁ , b ₄ , b ₅ and b ₇ in order from the value, and _{the signals c 1 and b 4 , b 5} and Obtain signals c ₄ , c ₅ and c ₇ below b ₇ .

Furthermore, the cutter load signal a ₂ is applied to the second, third, and sixth comparators 16, 17, and 20, respectively, and the second, third, and sixth set values b ₂ ,
b ₃ and b ₆ respectively to obtain signals c ₂ , c ₃ and c ₆ that exceed b ₂ , b ₃ and b ₆ , respectively.

On the other hand, the retraction side swing winch load signal _a1 and the unwinding side swing winch load signal _a3 are added to the subtracter 23, and the difference signal _a4 is added to the eighth comparator 22, and the eighth set value b Compare with ₈ b Signal less than ₈ c ₈
get.

The signals c ₁ and c ₂ are input to the first discriminator 24, and after c ₁ is input, c ₂ is input during the first set time period t ₁ .
is input, an output signal d ₁ is generated which indicates before the occurrence of rolling, and the second discriminator 25 receives the signals c ₃ and c ₄
and during the second set time period t ₂ after c ₃ is entered
When c ₄ is input, an output signal d ₂ indicating the occurrence of rolling is generated, and the third discriminator 26 receives the signals c ₅ and c ₆ .
is input, and after c ₅ is input, the third setting time period t ₃
When c ₆ is input in between, the output signal d ₃ indicates rolling expansion.
are generated and applied to the first braking signal generator 28, respectively.

The first braking signal generator 28 receives the signals d ₁ , d ₂ and
When either of _d3 is received, a first braking signal _e1 is generated to the unwinding side swing winch.

The value of the first braking signal e ₁ is, for example, as _shown in FIG.
When a is over ₁₁ , e ₁₁ is a constant value; when a is less than 0, then _{e 11 to} e ₁₂ is a value that increases in inverse proportion to the retraction side swing winch load signal a ₁ ; when it is less than 0, Make it a constant value of e ₁₂ .

Next, when the fourth discriminator 27 receives both the symbols c ₇ and c ₉ , it generates an output signal d ₄ indicating that the rolling trouble has not yet occurred.

When the second braking signal generator 29 receives the signal d ₄ , it generates a second braking signal e ₂ to the unwinding swing winch.

The value of the second braking signal _e2 is, for example, the difference _a4 between the swing winch load signals on the winding side and the winding side, as shown in Fig. 6.
If the value exceeds a ₄₁ , it is set to 0, and when a is less than ₀ , it is set to a value 0 to e ₂₁ that increases in inverse proportion to the signal a ₄ of the difference between the swing winch loads on the winding side and unwinding side.
When the signal a ₄ is less than 0, it is set to a constant value of e ₂₁ .

〔Effect of the invention〕

Since the device of the present invention has the above-described configuration, when the cutter rolls on the surface of the seabed, or when both the winding side and unwinding side swing wires are loosened, it is possible to adjust the situation to the unwinding side swing winch. This makes it possible to apply braking force that is appropriate for the dredging process, thereby preventing accidents from occurring and ensuring smooth dredging operations.

[Brief explanation of the drawing]

Figures 1 and 2 are an explanatory plan view and side view of the dredger, Figure 3 is a front view of the cutter, Figure 4 is a block diagram of the device of the present invention, and Figure 5 is the swing winch load on the retraction side. An explanatory diagram of the relationship between the first braking signal and FIG. 6 is an explanatory diagram of the relationship between the difference between the swing winch loads on the winding side and the unwinding side and the second braking signal. 1...hull, 2...rudder, 3...cutter,
4...Spud, 5,6...Swing winch,
7, 8... Swing wire, 9, 10... Anchor, 11... Seabed ground, 12... Unexcavated ground, 13, 14... Arrow, 15, 16, 17, 1
8, 19, 20, 21, 22... comparator, 23...
...subtractor, 24...first discriminator, 25...second discriminator, 26...third discriminator, 27...fourth discriminator, 28...first braking signal generator, 29...th 2
Braking signal generator.

Claims (1)

[Claims] 1. In the swing braking device of a cutter suction pump dredger that has an automatic braking mechanism for the swing winch, when the load signal of the swing winch on the engulfing side increases and then the load signal of the cutter increases, or When the load signal decreases and the cutter load signal increases, a first braking signal that is inversely proportional to the increase or decrease in the load signal of the retraction side swing winch is applied to the unwinding side swing winch, and further a load signal of the retraction side swing winch is applied. decreases, and when the difference between the load signal of the swing winch on the take-in side and the swing winch load signal on the take-out side decreases beyond a set value, the second braking is inversely proportional to the decrease in the swing winch load signal on the take-in side. A swing braking device for a dredger, characterized in that a signal is applied to the unwinding side swing winch.