JP7715263B2 - Underwater ball removal device - Google Patents

Description

The present invention relates to an underwater sling release device for a sling wire used to suspend an underwater structure.

Traditionally, wave-dissipating blocks and scour prevention materials, which are attached to wires suspended from cranes on work vessels, have been allowed to settle on the water bottom, and then the wires have been removed by hand underwater by divers. During the wire removal process, the up and down movement of the work vessel caused by waves is transmitted to the wires, making the process of removing the moving wires from the settled wave-dissipating blocks cumbersome.

For example, in Patent Document 1, a float is installed midway along the wire that suspends the sheathing block, preventing the up and down movement of the work vessel from being transmitted to the wire located below the float, improving the efficiency of the divers' work to remove the load. However, depending on the type of load, there is a risk of the load collapsing during the work, so there are safety issues with divers manually removing the load while in close proximity to it.

In light of this, various devices capable of remotely operating sling removal operations at sea or on land are being developed. For example, Patent Document 2 discloses a remote sling removal device equipped with a movable pin that is movable by a hydraulic cylinder, installed between the crane's wire and the sling wire rope. In this case, one end of the sling wire rope is attached to the movable pin, and the other end is attached to a heavy object, and the heavy object is then installed in the desired position using a crane. The position of the movable pin is then switched via a hydraulic control device, and one end of the sling wire rope is removed from the movable pin. This completes the sling removal operation, leaving the heavy object in the desired position, and the remote sling removal device is removed and recovered by a crane.

Patent Document 3 also describes a lifting and ball-removal device installed between the crane's suspension chain and the steel frame (suspended load). The lifting and ball-removal device is equipped with a suspension member attached to a wire suspended from a housing, and this suspension member is equipped with a pin that is attached and detached by the operation of a pneumatic cylinder. The pneumatic cylinder can be controlled wirelessly, and the steel frame is installed in the desired position using a crane with the pin passed through an opening in a suspension piece attached to the suspension member. The pin is then removed wirelessly from the suspension member to complete the ball-removal operation, leaving the steel frame in the desired position, and the lifting and remote ball-removal device is then removed and collected by the crane.

Japanese Patent Application Laid-Open No. 2017-7845 JP 2014-118237 A Japanese Utility Model Application Laid-Open Publication No. 7-23776

Devices such as those described in Patent Documents 2 and 3, which can be remotely operated to perform ball removal work on land or at sea, pose various challenges when used underwater. Specifically, devices using hydraulic cylinders, such as those described in Patent Document 2, run the risk of oil leaking in the event of an unexpected accident, resulting in environmental pollution. For this reason, their use is often restricted in construction work carried out in rivers or ocean areas. Furthermore, devices using pneumatic cylinders, such as those described in Patent Document 3, are not only prone to malfunction due to water pressure when used underwater, but also require greater power than when used on land. This means that the entire facility, including the power source, is likely to become excessively large, requiring, for example, an air supply compressor.

The present invention was developed in consideration of these issues, and its main purpose is to efficiently perform remote-controlled underwater ball removal operations.

In order to achieve this object, the underwater sling release device of the present invention is an underwater sling release device that releases underwater a sling wire that suspends an underwater structure, and is equipped with a sling release mechanism that includes a metal locking pin to which the sling wire is detachably attached, a pin holding plate with a through hole into which the locking pin is inserted, and a pin operating unit that moves the locking pin in the direction of insertion and removal relative to the pin holding plate, an insertion detection sensor that detects when the locking pin is inserted into the pin holding plate, and a removal detection sensor that detects when the locking pin is removed. and an insertion/removal state confirmation sensor, wherein the pin operating unit is arranged parallel to the locking pin and includes an extension device equipped with a ball screw and a connecting member connecting one end of the extension device and the locking pin , wherein the insertion detection sensor and the removal detection sensor are non-contact magnetic proximity sensors, the insertion detection sensor is arranged at a position where it can detect the locking pin when inserted into the through hole, and the removal detection sensor is arranged at a position where it can detect the locking pin when removed from the through hole .

The underwater ball removal device of the present invention is also characterized by including a cage that covers the top and sides of the ball removal mechanism.

The underwater sling removal device of the present invention employs an extension device equipped with a ball screw in the pin operating unit, which moves the locking pin in the direction of insertion and removal relative to the pin holding plate. This allows the locking pin with the sling wire attached to be inserted and removed relative to the pin holding plate without the extension device malfunctioning due to water pressure. Therefore, simply by operating the extension device, it is possible to reliably remove the sling wire from an underwater structure installed underwater.

Furthermore, telescopic devices equipped with ball screws do not have the risk of oil leaks, which can have a negative impact on the environment, as is the case with hydraulic telescopic devices, making them suitable for use in river and undersea construction projects.

Furthermore, by installing equipment to control the telescopic device equipped with a ball screw via wire or wirelessly, underwater workers can perform ball removal work remotely, thereby improving safety and work productivity.

In addition, an insertion/removal status confirmation sensor is provided that includes an insertion detection sensor and a removal detection sensor. By connecting an insertion detection light and a removal detection light to these insertion detection sensors, respectively, underwater and surface workers can check the insertion/removal status of the locking pin while remotely located from the underwater ball removal device.

According to the present invention, an extension device equipped with a ball screw is used in the pin operating unit, which moves the locking pin with the sling wire attached in the direction of insertion and removal from the pin holding plate. This makes it possible to efficiently perform remote-controlled sling removal operations underwater, despite the simple configuration.

1 is a diagram showing how an underwater structure is suspended using an underwater ball removal device according to an embodiment of the present invention. FIG. 1 is a perspective view showing an underwater ball removal device according to an embodiment of the present invention. 1 is a side view of an underwater ball removal device according to an embodiment of the present invention. 1 is a plan view of an underwater ball removal device according to an embodiment of the present invention. 1 is a diagram showing an example of an extension device equipped with a ball screw mechanism according to an embodiment of the present invention. FIG. 10A and 10B are diagrams showing the behavior of an extension device and a locking pin in an embodiment of the present invention. 3A and 3B are diagrams illustrating a control unit and an insertion/removal state confirmation sensor according to an embodiment of the present invention. 1 is a diagram showing an outline of an underwater slinging system according to an embodiment of the present invention. FIG. 1 is a diagram showing an outline of underwater acoustic communication equipment according to an embodiment of the present invention;

The present invention is a device and system that can remotely remove the slings from an underwater structure equipped with a sling wire after it has been installed underwater or has been landed on the bottom, and can be used in any water environment, including oceans, rivers, lakes, and marshes. The underwater structure can also be used for scour prevention materials such as rubble, or concrete blocks such as foot protection blocks and wave-dissipating blocks (e.g., Tetrapods (registered trademark)).

In this embodiment, we will use an underwater load rotation device to carry out installation work for wave-dissipating blocks, a type of underwater civil engineering work, as an example. Details of the underwater ball removal device and underwater ball removal system will be explained below with reference to Figures 1 to 9.

As shown in Figure 1, a lifting jig 5 is suspended in a horizontal position from the wire 4b of a crane 4a mounted on a crane ship 4 via an underwater load rotation device 3, and a wave-dissipating block B is suspended from this lifting jig 5.

The underwater load rotation device 3 is a device used underwater to rotate the suspended concrete block B to change direction, maintain its position, and perform other posture control, such as fine adjustments during positioning, when installing the wave-dissipating block B on the seabed. This underwater load rotation device 3 has a lifting wire 3b attached to the underside of the outer hull 3a, which suspends the lifting jig 5. For details on the principle of posture control using the underwater load rotation device 3, please refer to Japanese Patent No. 5,970,946.

The lifting jig 5 is made of H-shaped steel, and as shown in Figure 2, the sling wire 6 is installed directly near one end of the lower flange 5a, and the underwater sling release device 1 is installed near the other end. The sling wire 6 has a locking eye 6a formed at one end that is directly connected to the lifting jig 5, and a lockable eye 6b formed at the other end, which is attached to the underwater sling release device 1. Therefore, as shown in Figure 1, after the wave-dissipating block B around which the sling wire 6 is routed reaches the bottom in a predetermined position, the sling wire 6 can be removed from the wave-dissipating block B by releasing the connection between the underwater sling release device 1 and the lockable eye 6b.

<<Underwater ball removal device>>
As shown in the side view of Figure 3, the underwater ball removal device 1 comprises a ball removal mechanism 10, a sensor 20 for checking the insertion/removal state, a control unit 30, and a cage 40 for housing these components. The cage 40 is formed by attaching a wire mesh 42 to a substantially rectangular frame 41, but the shape of the cage is not limited to this.

<Ball removal mechanism>
As shown in FIG. 3, the ball removal mechanism 10 includes a mounting portion 11, a pair of pin holding plates 12, a locking pin 13, and a pin operating unit 14.

The mounting portion 11 is formed in a roughly T-shape by a joining steel plate 111 in a lying position and an upright steel plate 112 placed on its upper surface. The joining steel plate 111 is placed on the ceiling of the cage 40, and the upright steel plate 112 is placed so as to protrude upward from the cage 40. The upright steel plate 112 is inserted between a pair of device mounting portions 5c provided on the lower flange 5a of the lifting jig 5 and is connected to them via connecting pins 5d. In addition, a pair of pin holding plates 12 are installed on the underside of the joining steel plate 111 in a position parallel to the upright steel plate 112 with a predetermined gap between them.

As shown in the plan views of Figures 3 and 4, the pair of pin holding plates 12 each have opposing through holes 121. A locking pin 13, which moves along a guide tube 131, is inserted into these through holes 121 so that it can be inserted and removed. In Figures 3 to 6, the right side of the paper is referred to as the extraction side, and the left side is referred to as the insertion side.

The locking pin 13 is a long, rod-shaped member made of metal, and is fitted with the locking eye 6b of the sling wire 6, which is positioned between a pair of pin holding plates 12. The guide tube 131 is connected coaxially to the through-hole 121 on the outside of the pin holding plate 12a, which is located on the extraction side of the locking pin 13. The operation of moving the locking pin 13 in the insertion/removal direction is performed by the pin operating unit 14.

As shown in Figure 4, the pin operating unit 14 comprises an extension device 15, a coupling 16 connected to one end of the extension device 15, an underwater motor 17 connected to the extension device 15 via the coupling 16, and a connecting member 18 installed on the extension device 15.

The extension device 15 is positioned so that it extends and retracts parallel to the insertion and removal direction of the locking pin 13, and any type of extension device, such as an electric or ball screw type, may be used as long as it has a mechanism suitable for use underwater.

Mechanisms that are unsuitable for underwater use include hydraulically and pneumatically driven telescopic mechanisms. Hydraulically driven telescopic mechanisms have the potential to cause environmental problems, such as oil leaks, making them unsuitable for use in rivers or the ocean. Furthermore, pneumatically driven telescopic mechanisms not only have the potential to malfunction due to water pressure when used underwater, but also require the use of a separate air compressor, which can result in excessively large auxiliary equipment, making them unsuitable for underwater use.

Below, we will use a ball screw as an example of an extension mechanism suitable for use underwater, and explain an example of an extension device 15 using a ball screw with reference to Figure 5.

The telescopic device 15 includes a screw shaft 151, a ball nut 1521, a hollow rod 152 with the ball nut 1521 inside, and a protective tube 153 that houses the screw shaft 151 and hollow rod 152.

The screw shaft 151 is free to rotate about its axis, with the base end shaft portion 1512 supported by a centralizer 1531 provided inside the protective tube 153. A ball nut 1521 provided inside the hollow rod 152 is threadedly engaged with the threaded portion 1511, which extends from the middle portion toward the tip. The screw shaft 151 configured in this way is rotated by power supplied by the underwater motor 17.

The submersible motor 17 is mounted with its output shaft 171 intersecting the screw shaft 151. Therefore, the shaft portion 1512 of the screw shaft 151 and the output shaft 171 of the submersible motor 17 are connected via a coupling 16 that is capable of transmitting power via orthogonal or skewed shafts.

When the shaft 1512 of the screw shaft 151 and the output shaft 171 of the submersible motor 17 are arranged so as to form skewed shafts, the coupling 16 may be equipped with a worm gear. Specifically, a worm 161 is connected to the output shaft 171 of the submersible motor 17, and a worm wheel 162 is connected to the shaft 1512 of the screw shaft 151. This allows for smooth transmission of power from the output shaft 171 of the submersible motor 17 to the shaft 1512 of the screw shaft 151.

If the two are in a perpendicular axis relationship, then it is sufficient to use an appropriate gear such as a straight bevel gear or a spiral bevel gear. By arranging the two in a staggered or perpendicular axis relationship in this way, the width of the cage 40 can be made shorter and smaller compared to when they are arranged in series, and the underwater ball removal device 1 as a whole can be made slimmer.

The worm 161 and worm wheel 162 are housed in a housing 163 that is highly waterproof and pressure-resistant. The protective tube 153 of the telescopic device 15 described above is also fixed to the housing 163, and the protective tube 153 and the hollow rod 152 that extends from it are also highly waterproof and pressure-resistant, just like the housing 163.

3, the above-mentioned coupling 16 is fixed to a support column 164 hanging down from the ceiling of the cage 40 and is arranged on the insertion side of the locking pin 13. As a result, in the extension device 15, the screw shaft 151 connected to the coupling 16 is arranged on the insertion side and the hollow rod 152 is arranged on the extraction side. The connecting member 18 is connected to this hollow rod 152.

As shown in Figure 4, the connecting member 18 is arranged perpendicular to the hollow rod 152 and the aforementioned locking pin 13, connecting them together. Therefore, as shown in Figure 6(b), when it is desired to remove the locking pin 13 with the sling wire 6 attached from the through-hole 121 of the pair of pin holding plates 12, the screw shaft 151 is rotated to move the hollow rod 152 toward the removal side, thereby extending the extension device 15. As a result, as shown in Figure 6(a), the locking pin 13 is removed from the pair of pin holding plates 12 and the sling wire 6, completing the sling removal operation.

On the other hand, as shown in Figure 6(a), when it is desired to insert the locking pin 13 into the through-hole 121 of the pair of pin holding plates 12 and the sling wire 6 arranged between them, the screw shaft 151 is rotated in the reverse direction so that the hollow rod 152 moves toward the insertion side, thereby shortening the extension device 15. As a result, as shown in Figure 6(b), the locking pin 13 is inserted into the pair of pin holding plates 12 and the sling wire 6. An insertion/removal state confirmation sensor 20 is provided inside the cage 40 so that such an insertion/removal state can be recognized by a person at a distance.

<Insertion/removal status sensor>
The insertion/removal state confirmation sensor 20 is a sensor that detects the position of the locking pin 13 relative to the pair of pin holding plates 12, and as shown in Figures 3 and 4, it is equipped with an insertion detection sensor 21 and a removal detection sensor 22, and is installed at the desired position via an installation jig 23.

The insertion detection sensor 21 is located on the outer side of the pin holding plate 12b, which is located on the insertion side of the locking pin 13, directly above the through-hole 121. The removal detection sensor 22 is located directly above the removal end of the locking pin 13 when it has been removed from the pair of pin holding plates 12. These are attached via an installation jig 23 made of an angle bar, but the shape of the installation jig 23 is not critical, and installation does not require the use of an installation jig 23.

The insertion detection sensor 21 and removal detection sensor 22 use non-contact magnetic proximity sensors. Magnetic proximity sensors are widely used sensors that detect changes in impedance caused by metal approaching a magnetic field generated by a coil. For this reason, metal is used as the material for the locking pin 13.

The insertion/removal state confirmation sensors 20 arranged in these cages 40 are connected to the control unit 30 together with the underwater motor 17. Note that the insertion/removal state confirmation sensors 20 are not limited to this, and other sensors can be used as long as they are capable of detecting the locking pin 13 underwater.

<Control Unit>
The control unit 30 is installed in the cage 40 as shown in FIGS. 3 and 7, and includes a motor driver 31, a battery 32, and a waterproof pressure-resistant container 33 for accommodating these components.

The pressure-resistant vessel 33 has a connection panel 331 attached to its outer surface, which, as shown in Figure 7, is equipped with a sensor jack 331a and a motor jack 331b that connect the motor driver 31 and battery 32 to the insertion/removal state confirmation sensor 20 and the underwater motor 17. The connection panel 331 also has a removal detection light 331c and an insertion detection light 331d that light up when the insertion/removal state confirmation sensor 20 detects the locking pin 13. Both of these are LED lights.

As a result, the underwater motor 17 is controlled by the motor driver 31 to operate the extension device 15. When the locking pin 13 is pulled out of the through-hole 121 by operating the extension device 15, the pull-out detection sensor 22 detects the locking pin 13 and causes the pull-out detection light 331c to flash.

On the other hand, when the locking pin 13 is inserted into the through-hole 121, the insertion detection sensor 21 detects the locking pin 13 and causes the insertion detection light 331d to flash. The removal detection light 331c and the insertion detection light 331d may be arranged not only on the connection panel 331 of the pressure-resistant vessel 33, but also in a position that is easily visible to the underwater worker D and the surface worker S, such as outside the cage 40.

As shown in Figure 1, this allows underwater worker D and surface worker S to check the insertion/removal status of the locking pin 13 while remotely positioned from the underwater ball removal device 1. When the insertion detection sensor 21 and removal detection sensor 22 detect the locking pin 13, they send a detection signal to the motor driver 31. Upon receiving the detection signal, the motor driver 31 stops the underwater motor 17.

The connection panel 331 is also provided with a power supply jack 331e, as shown in Figure 7. When the power plug 34 is inserted into the power supply jack 331e, the power switch is turned on and the underwater ball release device 1 becomes usable. Furthermore, the battery 32 can be charged by removing the power plug 34 and inserting a charging cable (not shown). When the underwater ball release device 1 is not in use, a dummy plug (not shown) is inserted.

Furthermore, the connection panel 331 is equipped with a wired controller jack 331f and a wired controller 35 attached to it. The wired controller 35 is used to manually operate the underwater motor 17 and can take any form. For example, it can be set so that when the handle 351 is turned to the right, the underwater motor 17 rotates forward, and when turned to the left, it rotates reversely. This makes it possible to extend and retract the extension device 15 and move the locking pin 13 in the insertion/removal direction as appropriate.

As such, the underwater ball release device 1 can be operated via wired communication, but it can also be operated in combination with wireless communication equipment. Below, we will explain an underwater ball release system that combines the underwater ball release device 1 with underwater acoustic communication equipment, using underwater acoustic communication technology as an example.

<<Underwater ball removal system>>
8 and 9, the underwater payload removal system 100 comprises the above-mentioned underwater payload removal device 1 and underwater acoustic communication equipment 2. The underwater acoustic communication equipment 2 comprises a command information transmitting device 50 that allows the surface worker S to transmit command information M to the underwater payload removal device 1 as sound waves, and a machine control device 60 that receives the sound waves and controls the underwater payload removal device 1 based on the command information M.

The command information transmission device 50 and machine control device 60 are outlined below, but for details, please refer to Japanese Patent Application No. 2019-192086. In this embodiment, the command information M refers to "extension" and "contraction." "Extension" is a command to extend the extension device 15 to pull the locking pin 13 out of the through-hole 121 of the pair of pin holding plates 12, and "contraction" is a command to contract the extension device 15 to insert the locking pin 13 into the through-hole 121 of the pair of pin holding plates 12.

<Command information transmission device>
As shown in FIG. 9, the command information transmission device 50 includes a command input unit 51, an oscillator 52, a carrier wave selector 53, a modulator 54, an amplifier 55, and a transmitter 56.

The command input unit 51 is equipped with an input section into which the surface worker S or underwater worker D inputs operation commands for the extension device 15 of the underwater ball release device 1. The input section is provided with at least two operation command buttons: "extend" and "retract." The surface worker S or underwater worker D inputs operation commands for the extension device 15 by appropriately selecting one of these operation command buttons. The command input unit 51 also digitizes the input operation command, converting it into command information M, which is a baseband signal, and outputs it to the modulation unit 54.

Meanwhile, the oscillator 52 generates multiple reference waves W to be used as carrier waves C and outputs them to the carrier selection unit 53. The carrier selection unit 53 selects two or more of the multiple reference waves W to be used as carrier waves C and outputs them to the modulator 54, which is connected wirelessly or via a wire.

The modulation unit 54 performs so-called modulation, which involves mixing the command information M input from the command input unit 51 with each of two or more carrier waves C input from the carrier wave selection unit 53, to form multiple modulated waves Mw with different frequency bands. The multiple modulated waves Mw thus formed are output to an amplifier 55 connected wirelessly or via a wire. The modulation method used is BPSK (binary phase shift keying), which modulates by changing the phase without changing the frequency or amplitude of the carrier waves C.

With the above configuration, multiple modulated waves Mw carrying the same command signal M output from the modulation unit 54 are amplified by the amplifier 55, then D/A converted by the wave transmitter 56, a dedicated wave transmission transducer, and transmitted into the sea as sound waves. When the surface worker S operates the command information transmission device 50, the wave transmitter 56 may be in the air or may be suspended underwater as shown in Figure 8.

These multiple types of sound waves transmitted into the ocean may be transmitted with a time lag between them, or they may all be combined and transmitted simultaneously. The sound waves transmitted from the transmitter 56 are modulated waves Mw that have been D/A converted, and since the modulated waves Mw are carrier waves C modulated using the BPSK method, their frequency band is the same as that of the carrier waves C.

<Machine control device>
On the other hand, the mechanical control device 60 is provided in the pressure-resistant container 33 of the underwater ball removal device 1, as shown in Figure 3, and its configuration includes a receiver 61, a frequency diversity unit 62, an amplifier 63, a demodulation unit 64, and a control unit 65, as shown in Figure 9.

The wave receiver 61 is a dedicated wave receiving transducer that collects various underwater sound waves, performs A/D conversion, and converts them into an input electrical signal Ms', and in this embodiment, a hydrophone capable of handling the audible range is used. The sound waves collected by these wave receivers 61 are multiple types of sound waves based on multiple modulated waves Mw transmitted from the wave transmitter 56. As shown in Figure 8, multiple such wave receivers 61 are provided in the cage 40, and the position and number of such receivers 61 may be any position that makes it easy to receive sound waves.

The frequency diversity unit 62 continuously analyzes the quality of the input electrical signal Ms' using the carrier frequency bands of each of the multiple carrier waves C selected by the carrier wave selection unit 53 of the command information transmission device 50, and the frequency bands of the harmonics of each carrier wave C. Note that harmonics refer to waveforms with frequencies that are integer multiples of the fundamental frequency waveform. Of the input electrical signal Ms', the most reliable signal that originates from the carrier wave C or its harmonics is extracted as a processed electrical signal Ms corresponding to the modulated wave Mw or its harmonics, and output to the wired or wirelessly connected amplifier 63.

The amplifier 63 amplifies the processed electrical signal Ms, which corresponds to the modulated wave Mw or its harmonics, and outputs it to a wired or wirelessly connected demodulator 64. The demodulator 64 demodulates the amplified processed electrical signal Ms and obtains command information M related to the operation command input by the command input unit 51 of the command information transmission device 50, which is then output to the control unit 25. The control unit 65 transmits the command information M extracted by the demodulator 64 to the motor driver 31 as a control signal.

As described above, the underwater payload removal system 100 uses the underwater acoustic communication equipment 2 to transmit into the sea the operation commands of the surface worker S or the underwater worker D for the extension device 15 of the underwater payload removal device 1, which are input to the command information transmission device 50. Furthermore, by receiving this information with the machine control device 60, it becomes possible to control the operation of the extension device 15 based on the command information M.

In this embodiment, three types of carrier waves (2 kHz, 2.25 kHz, 2.5 kHz) are selected by the carrier wave selection unit 53 from within the audible range (generally between 20 Hz and 20 kHz), and these are used to transmit the same command signal M as sound waves into the sea. In this way, by setting the frequency band of the sound waves within the audible range, underwater worker D can recognize from the sound waves that he is performing a ball removal operation, even in highly turbid water.

In addition, compared to using ultrasound, which is generally used in underwater acoustic communications, it is possible to minimize the effects of the phenomenon known as Doppler shift, in which the frequency band changes due to the relative speed difference between the transmitter and receiver, and the phenomenon known as multipath fading, in which the received strength of sound waves fluctuates.

Furthermore, three types are selected from within the audible range, and these are used to transmit the same command signal M into the sea as sound waves. Therefore, when receiving the sound waves, the one that is least affected by various phenomena such as the Doppler shift and multipath fading mentioned above, as well as underwater noise, can be selected and received to obtain the command information M. This makes it possible to further improve communication stability.

<<<How to install concrete blocks using an underwater ball removal system>>>
The specific steps of the method for installing the wave-dissipating block B on the seabed using the underwater ball removal system 100 having the above configuration will be described below.

After pre-charging the battery 32 provided in the control unit 30 of the underwater ball removal device 1, insert the power plug 34 into the power jack 331e provided on the connection panel 331 of the control unit 30, as shown in Figure 7.

At the same time, the lifting jig 5 is suspended from the underwater lifting and slewing device 3 suspended from the wire 4b of the crane 4a mounted on the crane ship 4. Also, as shown in Figure 2, a sling wire 6 is connected to one end of the lower flange 5a of the lifting jig 5 via a locking eye 6a, and an underwater sling release device 1 is installed at the other end. The sling wire 6 is then looped around a wave-dissipating block B placed on the ground, and the locking eye 6b of the sling wire 6 is positioned between a pair of pin holding plates 12 provided on the sling release mechanism 10, as shown in Figure 6(a).

After this, as shown in Figure 6(b), the locking eye 6b of the sling wire 6 is attached to the locking pin 13. Since these operations are performed on land or on a ship, to illustrate the case where the wired controller 35 is used, first, the locking eye 6b is placed between the pair of pin holding plates 12. Next, the handle 351 of the wired controller 35 is turned to the right or left (to shorten the extension device 15).

Then, a control signal is sent from the wired controller 35 to the motor driver 31, and the underwater motor 17 supplies power to retract the extension device 15. As a result, the locking pin 13 connected to the extension device 15 via the connecting member 18 moves toward the side where it is inserted into the through-holes 121 of the pair of pin holding plates 12, and the sling wire 6 is attached to the locking pin 13, as shown in Figure 6 (b).

Furthermore, when the locking pin 13 is inserted into the through-hole 121 of the pair of pin holding plates 12, the insertion detection sensor 21 detects the locking pin 13 and sends a detection signal to the insertion detection light 331d and motor driver 31. This causes the insertion detection light 331d to light up, indicating that the locking pin 13 has been inserted, and the motor driver 31 stops the underwater motor 17, thereby halting the retraction operation of the extension device 15.

After this, the underwater load rotation device 3 and the lifting jig 5 are lifted by the crane 4a, and after confirming that the wave-dissipating block B can be lifted in a stable state, the crane 4a is operated to lift the wave-dissipating block B and lower it to the desired position in the sea. The underwater load rotation device 3 is then used to adjust the direction and posture of the wave-dissipating block B, and the wave-dissipating block B is then installed on the seabed.

After confirming that wave-dissipating block B has reached the bottom, underwater worker D operates the "extend" operation command button on the command input unit 51 of the command information transmission device 50, and transmits the "extend" command information as sound waves to the machine control device 60.

When the machine control device 60 receives the "extend" command, the control unit 65 sends a control signal to the motor driver 31, and the extension device 15 is extended by power supplied from the underwater motor 17. As a result, the locking pin 13 connected to the extension device 15 via the connecting member 18 moves toward the side where it is pulled out of the through-holes 121 of the pair of pin holding plates 12, and the sling wire 6 is released from the locking pin 13, as shown in Figure 6(a).

After the sling removal work is completed, the sling wire 6, lifting jig 5, and underwater load rotation device 3 are lifted and removed by the crane 4a. This work is repeated until all of the wave-dissipating blocks B have been installed on the seabed.

As described above, with the underwater sling release device 1, the locking pin 13 to which the sling wire 6 is attached can be inserted and removed from the pair of pin holding plates 12 without the extension device 15 malfunctioning due to water pressure. Therefore, simply by operating the extension device 15, it is possible to reliably remove the sling wire 6 from the wave-dissipating block B installed underwater.

Furthermore, the underwater payload removal system 100 described above utilizes underwater acoustic communication equipment 2, allowing stable control of the extension device 15 and the payload removal work to be carried out at work sites with a variety of water environments, regardless of water quality, etc. Therefore, underwater worker D can carry out work safely while maintaining a constant distance from the underwater payload removal device 1. Furthermore, because the frequency band of the sound waves is set within the audible range, underwater worker D can recognize from the sound waves that the payload removal work is being carried out, even in highly turbid water.

The above embodiments are intended to facilitate understanding of the present invention and are not intended to limit the scope of the present invention. The present invention may be modified or improved without departing from its spirit, and it goes without saying that the present invention includes equivalents.

For example, in this embodiment, the underwater ball release system 100 is configured to include underwater acoustic communication equipment 2, and the underwater ball release device 1 is controlled by remote control using underwater acoustic communication technology, but visible light communication technology using visible light may also be used. For details on underwater visible light communication technology, see, for example, Japanese Patent No. 5,970,946.

In addition, in this embodiment, the insertion/removal state of the locking pin 13 relative to the pair of pin holding plates 12 is detected using an insertion/removal state confirmation sensor 20. However, this is not limited to this, and the state of the locking pin 13 may also be detected based on the operating time or amount (number) of rotations of the submersible motor 17. The submersible motor 17 may also be equipped with a pressure compensator to ensure operational stability.

Furthermore, in this embodiment, the insertion/removal state of the locking pin 13 is confirmed by the insertion/removal state confirmation sensor 20, and this information is reported visually by the removal detection light 331c and the insertion detection light 331d, but this is not limited to this, and for example, a device that provides auditory recognition may also be used.

1 Underwater lifting device 2 Underwater acoustic communication equipment 3 Underwater lifting and rotating device 3a Hull 3b Lifting wire 4 Crane ship 4a Crane 4b Wire 5 Lifting jig 5a Lower flange 5b Upper flange 5c Pair of device mounting parts 5d Connecting pin 6 Lifting wire 6a Locking eye 6b Locked eye 10 Lifting mechanism 11 Mounted part 111 Bonding steel plate 112 Standing steel plate 12 Pair of pin holding plates 121 Through hole 13 Locking pin 131 Guide tube 14 Pin operating unit 15 Extension device 151 Screw shaft 1511 Threaded portion 1512 Shaft portion 152 Hollow rod 1521 Ball nut 153 Protective tube 1531 Centralizer 16 Coupling 161 Worm 162 Worm wheel 163 Housing 164 Support column 17 Underwater motor 171 Output shaft 18, connecting member 20, insertion/removal state confirmation sensor 21, insertion detection sensor 22, removal detection sensor 23, installation jig 30, control unit 31, motor driver 32, battery 33, pressure-resistant container 331, connection panel 331a, sensor jack 331b, motor jack 331c, removal detection light 331d, insertion detection light 331e, power supply jack 331f, wired controller jack 331g, acoustic communication jack 34, power plug 35, wired controller 351, handle 40, gauge 41, frame 42, wire mesh 50, command information transmission device 51, command input unit 52, oscillator 53, carrier wave selection unit 54, modulator 55, amplifier 56, transmitter 60, machine control device 61, receiver 62, frequency diversity unit 63, amplifier 64, demodulator 65, control unit B, wave-dissipating block (underwater structure)
C Carrier wave M Command information W Reference wave Mw Modulated wave Ms' Input electrical signal Ms Processed electrical signal S Surface worker D Underwater worker

Claims (2)

An underwater sling release device that releases a sling from a sling wire that suspends an underwater structure underwater,
a sling removal mechanism including a metal locking pin to which the sling wire is detachably attached, a pin holding plate having a through hole into which the locking pin is inserted, and a pin operating unit that moves the locking pin relative to the pin holding plate in a direction to insert or remove the locking pin;
an insertion/removal state confirmation sensor having an insertion detection sensor that detects a state in which the locking pin is inserted into the pin holding plate and a removal detection sensor that detects a state in which the locking pin is removed,
The pin operating unit
An extension device arranged parallel to the locking pin and equipped with a ball screw;
a connecting member that connects one end of the extension device and the locking pin ,
The insertion detection sensor and the removal detection sensor are non-contact magnetic proximity sensors,
An underwater ball removal device characterized in that the insertion detection sensor is positioned at a position where it can detect the locking pin when inserted into the through hole, and the withdrawal detection sensor is positioned at a position where it can detect the locking pin when withdrawn from the through hole . The underwater ball removal device according to claim 1,
An underwater ball removal device characterized by comprising a cage that covers the top and sides of the ball removal mechanism.