JPH0119012B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a drag suction type dredger, and more particularly to a device capable of automatically controlling the depth of its drag head.

Conventionally, in self-propelled drag suction type dredges, dredging drag head 1 (first
The depth of the drag arm (see figure) is adjusted by the action of the winch from which the drag arm is suspended and the swell compensator 2 (see figure 1).

An example of an automatic dredging device that controls such a drag head is disclosed in Japanese Patent Publication No. 51-45169.

However, conventionally, the depth control of the drag head 1 is performed so as to almost follow the surface irregularities of the accumulated sediment 3 as shown in FIG. ′
Dredging of such unnecessary earth and sand 3' increases the number of trips of the dredger between the dredging site and the earth and sand disposal site, resulting in a significant drop in work efficiency.

In addition, FIG. 1 shows the trajectory of the drag head 1 moving along the accumulated earth and sand 3 in the downward direction, and also shows the position of the swell compensator 2 in the upward direction corresponding to the trajectory of the drag head 1. The symbol a is the point in time when the swell compensator 2 starts lowering the winch after a predetermined time τ1 after passing the lower limit control point, and b is the point in time when the swell compensator 2 reaches the neutral point and stops the winch. c is the point at which the swell compensator 2 reaches the upper limit control point and winds up the winch, d is the point at which the swell compensator 2 becomes the neutral point and stops the winch, and e is the point when the swell compensator 2 passes the lower limit control point. , the point in time when the winch is lowered after a predetermined time τ1, and f indicates the point in time when the swell compensator 2 reaches the neutral point and the winch is stopped.

Therefore, it is conceivable to avoid dredging unnecessary earth and sand 3' each time through an operator's operation, but this would be an extremely troublesome task.

As such conventionally known technology,
There is something shown in Publication No. 2139, and this technology is
The angle of inclination of the pump dredger's rudder, the hull draft near the axis of the rudder, and the tide level of any water area outside the ship are automatically measured, and three signals corresponding to these measured values are used as elements to automatically calculate from the reference sea level. This technology is equipped with a calculation mechanism that calculates the depth to the cutter at the tip of the rudder, and a gauge that displays the depth, but this technology has the trouble of having to measure the rudder inclination angle and hull draft. In addition, there is the trouble of requiring operator operations depending on the measurement results.

Furthermore, the conventional method has a problem in that the drag head 1 must be adjusted up and down in response to changes in the draft of the dredge.

The present invention is an attempt to solve the above-mentioned problems of the conventional device.The present invention automatically adjusts the depth of the drag head so as not to dredge unnecessary earth and sand, and also to automatically correct for changes in draft. The purpose is to provide a device that can be controlled.

For this reason, the automatic drag head depth control device of the present invention includes a drag arm having a base end pivotably connected to a ship's hull and a drag head at a distal end, and a drag head on a ship that can drive the drag arm via a wire to adjust the depth of the drag head. It is equipped with a winch and a swell compensator that can automatically adjust the tension of the wire by supporting an intermediate portion of the wire on the ship, and a depth detector is provided on the drag head,
The swell compensator is provided with a position detector at the operating end, and the difference signal is determined according to the difference signal between the detection signal from the depth detector and the set depth signal, and the position signal from the position detector. exceeds a specified upper limit, and when the position signal exceeds the specified upper limit, a signal for high-speed hoisting of the winch is output to the control panel of the winch, and the difference signal exceeds the specified upper limit; When the position signal exceeds the specified lower limit value, a signal for low-speed lowering of the winch is output to the control panel, and when the difference signal is below the specified lower limit value, a signal for low-speed lowering of the winch is output. The present invention is characterized in that a drag head depth control means is provided for outputting a signal to the control panel of the winch.

The automatic drag head depth control device as an embodiment of the present invention will be explained below with reference to the drawings. Fig. 2 is an explanatory diagram showing its operation, Fig. 3 is an overall configuration diagram thereof, and Fig. 4 is a diagram showing the device equipped with this device. 5 is a block diagram showing the main parts of the dredge, FIG. 6 is a flowchart for explaining its operation, FIG. 7 is a schematic diagram showing the operation of the swell compensator, and FIG. 8 is a side view showing the dredge. The figure is an explanatory diagram showing its operation, and Figure 9 is a block diagram of a circuit that controls the winch depending on the position of the swell compensator. In each figure, the same symbols as in Figure 1 refer to almost the same parts. It shows.

As shown in FIG. 4, a pair of port and starboard drag arms 5 have their base ends pivoted to a drudger hull 6.

In addition, a drag head 1 is provided at the tip of each drag arm 5, and the accumulated dirt 3 is passed through the drag head 1 through the drag arm 5.
is sucked into the hull 6.

Furthermore, a drive mechanism 7 is provided which can adjust the depth of the drag head 1 by rotating the drag arm 5, and this drive mechanism 7 is configured with a drag head winch 8 and an intermediate joint winch 9. .

The drag head winch 8 is used to wind up or lower a wire 10 connected to the drag head 1, and the middle portion of the wire 10 is supported by a swell compensator 2 on board.

The swell compensator 2 changes the tension of the wire 10 by moving the piston 2b up and down by adjusting the air pressure sealed in the cylinder of an actuator (not shown), and as shown in FIGS. It is now possible to take the lower limit or vice versa.

Further, the intermediate joint winch 9 is for winding up or lowering the wire 11 connected to the vicinity of the intermediate joint 5a of the drag arm 5.

By the way, each drag head 1 is provided with a depth detector 12, and this depth detector 12 converts, for example, water pressure or the like into a corresponding electric signal and outputs it. The value of the electrical signal to be converted is, for example, 4 to 20 mA for a water depth of 0 to 22 m.
That's about it.

Further, a depth control means 13 is provided which receives the detection signal SD from the depth detector 12 and outputs a control signal to the drive mechanism 7 according to the difference between the detection signal SD and the set depth signal SS. Means 13
As shown in FIG. 3, it is comprised of automatic control panels 14, 14 for port and starboard, a central control panel 15, and winch control panels 16, 16 for port and starboard.

Reference numeral 17 indicates a pen recorder for recording changes in depth and tide level of the drag head 1, and 18 indicates a drag arm operation panel.

Here, the automatic control panel 14, central control panel 15, pen recorder 17, and drag arm operation panel 18 are installed in a wheelhouse 19, and the winch control panel 16 is installed in a pump room 20.

In addition, from the automatic control panel 14 to the winch control panel 16
The portion of the signal line on the inner upper deck 21 is protected by a flexible tube 22.

As shown in FIG. 5, the automatic control panel 14 has on its panel surface 23 a set depth knob 24 for inputting the set depth of the drag head 1, and a tide level knob 25 for inputting the tidal level fluctuation value.

Further, a set depth signal generator 27 is provided which outputs a set depth signal corresponding to, for example, 0 to 22 m according to the value of the set depth knob 24, and further, according to the value of the tide level knob 25, for example, +9 to -1 m. A tide level signal generator 28 is provided which outputs a tide level correction signal corresponding to the tide level correction signal.

Note that correction of the tide level is performed manually or automatically at predetermined intervals.

Further, the signals from the generators 27 and 28 are added together by an adder 29 and inputted to a subtracter 30 as a set depth signal SS.

This subtracter 30 subtracts the detection signal SD from the depth detector 12 from the set depth signal SS and outputs the deviation signal Sε. is supplied to a group of comparators.

The comparator 31 activates the relay 34 and turns on the switch 37 connected to the control power supply if the deviation signal Sε is larger than a certain positive threshold; otherwise it deactivates the relay 34 and turns on the switch. This is a comparator for detecting a positive deviation component, which turns off 37.

If the deviation signal Sε is smaller than a certain negative threshold value, the comparator 33 activates the relay 36 and turns on the switch 38 connected to the winch low-speed hoisting control power supply; otherwise, the comparator 33 deactivates the relay 36. This is a comparator for detecting a negative deviation component that turns off the switch 38.

Note that FIG. 8 schematically shows areas where the deviation is positive and areas where the deviation is negative.

Further, the comparator 32 is a comparator for detecting a deviation neutral state that activates the relay 35 when the deviation signal Sε is between the above thresholds, and deactivates the relay 35 otherwise.

Note that when the relays 34, 35, and 36 are activated, the deviation display lamps 26b, 26c, and 26d of the display lamp group 26 on the panel surface 23 are lit, respectively, to notify the current deviation state.

Also, when the power is on, the lamp 26a
Furthermore, the signal S1 from the switch 37 is transmitted to a control circuit 39 which controls the hoisting, lowering and stopping of the winches 8 and 9 according to the operating end position (hereinafter simply referred to as "position") of the swell compensator 2.
is input to.

As shown in FIG. 9, this control circuit 39 is turned on upon receiving the signal S1 from the switch 37.
It is provided with interlocking switches 40 and 41 that are turned off in other cases.

The control circuit 39 also includes a comparator group consisting of comparators 43, 44, and 45 that receive a signal from a swell compensator position detector 42 that detects the position of the swell compensator 2.

Comparator 43 is swell compensator 2
When the position of
Turn on the switch 49 connected through 0,
Otherwise, the relay 46 is deactivated and the switch 49 is turned off.

Comparator 45 is swell compensator 2
When the position falls below the lower limit, the relay 48 is activated to turn on the switch 50 connected to the winch low-speed lowering control power source via the switch 41, otherwise the relay 48 is deactivated. This turns off the switch 50.

Comparator 44 is swell compensator 2
The relay 47 is activated when the position is between an upper limit and a lower limit including the neutral point.

It should be noted that when the relays 46, 47, and 48 are activated, a display lamp (not shown) on the board displays the position of the swell compensator 2.

Moreover, the on/off control of the switches 49 and 50 is as follows.
This can also be done by operating a limit switch that detects the upper and lower limit positions of the swell compensator 2.

Thereby, when the deviation signal Sε is larger than a certain positive threshold value, it is possible to further control the hoisting, lowering and stopping of the winches 8 and 9 by the position of the swell compensator 2.

That is, when the position of the swell compensator 2 is between the upper limit and the lower limit including the neutral point, the winches 8 and 9 are stopped, and when the position of the swell compensator 2 is at the upper limit, the winches 8 and 9 are stopped.
When the swell compensator 2 is at the lower limit, the winches 8 and 9 can be controlled to be lowered at a low speed.

Then, signals S3 from switches 49 and 50,
S4 and signal S2 from switch 38 are each output to winch control panel 16.

That is, the automatic control panel 14 determines the deviation between the depth of the drag head and the set depth, and
Signals for hoisting, lowering and stopping the winches 8, 9 can be supplied to the winch control panel 16.

In addition to the above-mentioned tide level correction function, the automatic control panel 14 has control functions such as various status displays and a switch for lifting the drag head 1 when the drag arm 5 is turned.

That is, when turning, a control signal for lifting the drag arm is output from the automatic control panel 14 to the winch, whereby the drag head 1 is lifted to a depth position shallower than the dredging depth. As a result, the drag head 1 will not cause any damage even on extremely uneven surfaces.
As a result, extremely safe turning operations can be performed.

Further, the winch control panel 16 is for receiving signals from the automatic control panel 14 and controlling the electric motors for the winches 8 and 9.

Further, the central control panel 15 is an extension control terminal of the automatic control panel 14, and can collectively control the drag arms 5 on both the port and starboard sides.

Since the apparatus of the present invention is constructed as described above, the depth control of the drag head 1 is automatically performed as follows.

First, by moving the dredge,
When the drag head 1 passes the lower limit value 4L of the set depth 4 by moving the drag head 1 as shown by the arrow m in Fig. 2 and entering the part where the earth and sand 3' is below the set depth 4 (symbol A). ), the deviation is negative, so the time τ2
Later (see position indicated by symbol B), winches 8, 9
winding starts at low speed.

As a result, the drag head 1 is gradually lifted up, and when the drag head 1 reaches the set depth 4 (see position C), the winches 8 and 9 stop hoisting.

After that, when the draft of the dredge increases and drag head 1 passes the lower limit value 4L (see the position indicated by symbol D), the deviation becomes negative again, so winches 8 and 9 are kept at low speed until drag head 1 reaches the set depth 4. It is rolled up.

Conversely, when the draft of the drudger decreases and the drag head 1 passes the upper limit value 4U (see the position indicated by symbol E), the deviation becomes positive, but at this time the position of the swell compensator 2 is at the lower limit alarm point, so The winches 8 and 9 are lowered at low speed until the drag head 1 reaches the set depth 4.

In this way, in places where there is accumulated soil 3' in a depressed area below the set depth 4, the drag head 1 skips while maintaining the set depth 4, so unnecessary soil 3' is not dredged. .

Next, when the drag head 1 moves to a place where the sediment 3 is above the set depth 4 and passes the upper limit value 4U of the set depth 4 (see the position indicated by the symbol F), the deviation becomes positive, but At this time, since the position of the swell compensator 2 is at the lower limit alarm point, lowering of the winches 8 and 9 is started at a low speed after a delay of time τ3 (see the position indicated by symbol G).

As a result, drag head 1 gradually lifts up.
When the tension of the wire 10 is relaxed and the swell compensator 2 is raised to a neutral point (see the position indicated by the symbol H), the operation of the winches 8 and 9 is stopped.

When the drag head 1 is further lifted by the accumulated earth and sand 3 and the swell compensator 2 reaches the upper limit control point (see the position indicated by the symbol I), the winches 8 and 9 are hoisted at high speed and the wire 10 is pulled. Therefore, the swell compensator 2 quickly lowers, and when the swell compensator 2 reaches the neutral point again (see the position indicated by the symbol J), the winches 8 and 9 are stopped.

After that, after passing the peak of the uplift of sediment 3',
As the drag head 1 goes down, the swell compensator 2 also goes down, but when the swell compensator 2 reaches the lower limit control point (see the position indicated by K), the winches 8 and 9 are lowered at low speed. .

As a result, the swell compensator 2 comes to the neutral point again (see the position indicated by the symbol L), but at this time the winches 8 and 9 are stopped from operating.

When the drag head 1 moves again to a place where the sediment 3' is below the set depth 4 and passes the lower limit 4L of the set depth 4 (see the position indicated by the symbol M),
After the time τ4 (see the position indicated by the symbol N), the winches 8, 9 start hoisting at a low speed.

As a result, the drag head 1 is gradually lifted up, and when the drag head 1 reaches the set depth 4 (see the position indicated by the symbol P), the winches 8 and 9 stop hoisting.

Thereafter, the drag head 1 skips the depressed portion in substantially the same manner as described above, so that unnecessary earth and sand 3' is not dredged.

Incidentally, the state of the above-mentioned work is shown in a flowchart as shown in FIG. 6.

In addition, the depth maintenance function of the drag head 1 also includes changes in the draft of the dredge, so even if the cargo condition changes and the draft changes,
There is no need to readjust the depth of drag head 1.

As described in detail above, the automatic drag head depth control device of the present invention provides the following effects and advantages.

(1) Since dredging is carried out to the necessary depth according to the undulations of the seabed, and unnecessary areas are removed, the amount of dredged soil can be kept to the minimum required.

(2) Since unnecessary earth and sand are not loaded, the number of trips to the earth and sand dump site is reduced, and work efficiency can be improved.

(3) It is not affected by changes in draft from the shallow draft at the start of dredging to the deep draft just before completion, eliminating the need for the operator to constantly monitor and make manual corrections.

(4) Since the depth detector directly measures and outputs the depth from the water surface to the drag head, there is no need to install an inclinometer or draft gauge, and there is no need for correction.

(5) Not only the depth of the drag head is controlled according to the difference signal between the detection signal from the depth detector and the set depth signal and the position signal of the operating end of the swell compensator, but also the speed of change of depth is controlled. As a result, the drag head can quickly respond to the undulations of the seabed, and dredging can be carried out smoothly in areas where dredging is not necessary.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing the action of a conventional drag head depth control means, and FIGS. 2 to 9 show an automatic drag head depth control device as an embodiment of the present invention. FIG. 3 is an overall configuration diagram, FIG. 4 is a side view of a dredge equipped with this device, FIG. 5 is a block diagram showing its main parts, and FIG. 6 explains its function. Figure 7 is a schematic diagram showing the action of the swell compensator, Figure 8 is an explanatory diagram showing the action, and Figure 9 is a circuit that controls the winch depending on the position of the swell compensator. FIG. 1... Drag head, 2... Swell compensator, 2b... Piston, 3, 3'... Earth and sand,
4... Setting depth, 4L... Lower limit of setting depth, 4
U... Upper limit of set depth, 5... Drag arm,
6... Hull, 7... Drive mechanism, 8, 9... Winch, 10, 11... Wire, 12... Depth detector, 13... Depth control means, 14... Automatic control panel, 15... Center Control panel, 16... Winch control panel, 17... Pen recorder, 18... Drag arm operation panel, 19... Wheelhouse, 20... Pump room,
21... Upper deck, 22... Flexible tube, 23... Panel surface, 24... Setting depth knob, 2
5... Tide level knob, 26... Display lamp group, 26
a-26d...Display lamp, 27...Setting depth signal generator, 28...Tide level signal generator, 29...Adder, 30...Subtractor, 31-33...Comparator, 34-36... Relay, 37, 38...Switch, 39...Control circuit, 40, 41...Switch, 42...Swell compensator position detector, 43-45...Comparator, 46-48...
...Relay, 49,50...Switch.

Claims (1)

[Claims] 1. A drag arm whose base end is pivotally connected to the hull and has a drag head at the tip, an onboard winch that can drive the drag arm via a wire to adjust the depth of the drag head, and a midway portion of the wire supported on the boat. and a swell compensator that can automatically adjust the tension of the wire, and the drag head is provided with a depth detector, and the swell compensator is provided with a position detector of an operating end, and the swell compensator is provided with a position detector of an operating end, and a According to the difference signal between the detection signal and the set depth signal and the position signal from the position detector, when the difference signal exceeds the specified upper limit value and the position signal exceeds the specified upper limit value, the above-mentioned A signal for high-speed hoisting of the winch is output to the control panel of the winch, and when the above-mentioned difference signal exceeds the specified upper limit value and the above-mentioned position signal exceeds the specified lower limit value, a signal for low-speed lowering of the winch is output. drag head depth control means for outputting a signal for low-speed hoisting of the winch to the control panel of the winch when the difference signal falls below a specified lower limit value. An automatic drag head depth control device featuring: