Underwater ball removal system

Abstract

To efficiently carry out unslinging work in water through a remote control operation.SOLUTION: This underwater unslinging system comprises: an underwater unslinging device that unslings a slinging wire for suspending an underwater structure in water; and an underwater acoustic communication facility. The underwater unslinging device has an unslinging mechanism provided with a locking pin to which the slinging wire is detachably fitted, a pin holding plate having a through-hole into which the locking pin is inserted, and a pin operation unit that moves the locking pin in an inserting / pulling-out direction with respect to the pin holding plate. The pin operation unit is disposed in parallel with the locking pin, and provided with an elongation device having a ball screw and a connection member for connecting one end of the elongation device to the locking pin. The underwater acoustic communication facility includes a command information transmission device that transmits command information as a sound wave to the elongation device, and a machine control device that receives the command information transmitted as the sound wave from the command information transmission device, and controls the elongation device on the basis of the command information. The sound wave has a frequency band set within an audible range.SELECTED DRAWING: Figure 9

Description

[Technical field]

[0001] The present invention relates to an underwater sling release system for a sling wire used to suspend an underwater structure. [Background technology]

[0002] Conventionally, after the wave-dissipating blocks or scour prevention materials, which are attached with wires suspended from a crane on a work vessel, are landed on the bottom of the water, the work of removing the wires is manually performed underwater by divers. During the work of removing the wires, the vertical movement of the work vessel caused by the waves is transmitted to the wires, so the work of removing the wires, which move up and down, from the wave-dissipating blocks that are landed on the bottom can be complicated.

[0003] For this reason, for example, in Patent Document 1, a float is installed midway along the wire that suspends the sheathing block, preventing the vertical 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 rope. However, depending on the type of suspended load, there is a risk of the load collapsing during the work, and there are safety issues with the manual work of removing the rope by divers in close proximity to the load.

[0004] In this situation, various devices capable of remotely performing slinging work on the sea or land are being developed. For example, in Patent Document 2, a remote slinging device with a movable pin that is movable by a hydraulic cylinder is installed between the crane wire and the slinging wire rope. In this case, one end of the slinging wire rope is attached to the movable pin, and the other end is attached to a heavy load, and the heavy load is installed in a desired position by a crane. After this, the position of the movable pin is switched via a hydraulic control device, and one end of the slinging wire rope is removed from the movable pin. This completes the slinging work, the heavy load is left in the desired position, and the remote slinging device is removed and collected by a crane.

[0005] In addition, in Patent Document 3, a lifting and ball removal device is installed between the hanging chain on the crane side and the steel frame (suspended load). The lifting and ball removal device is equipped with a hanging member on a wire suspended from a housing, and this hanging member is provided 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 by a crane with the pin passing through an opening in a hanging piece provided on the steel frame and attached to the hanging member. Thereafter, the pin is removed from the hanging member by wireless control to complete the ball removal work, the steel frame is left in the desired position, and the lifting and remote ball removal device is removed and collected by a crane. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2017-7845 A [Patent Document 2] JP 2014-118237 A [Patent Document 3] Japanese Utility Model Application Publication No. 7-23776 Summary of the Invention [Problem to be solved by the invention]

[0007] Devices capable of remotely operating the ball removal work on land or sea as in Patent Documents 2 and 3 will cause various problems if they are used underwater as is. Specifically, devices using hydraulic cylinders as in Patent Document 2 may cause oil leakage due to an unexpected incident, resulting in environmental pollution. For this reason, their use is often restricted in construction work carried out in rivers and sea areas. In addition, devices using pneumatic cylinders as in Patent Document 3 are prone to malfunction due to the application of water pressure when used underwater, and require a larger power source than when used on land. For this reason, the entire equipment, including the power source, is likely to become excessively large, such as requiring an air supply compressor.

[0008] The present invention has been made in consideration of such problems, and its main object is to efficiently perform remote-controlled ball removal work underwater. [Means for solving the problem]

[0009] In order to achieve this object, the underwater sling removal system of the present invention is an underwater sling removal system comprising an underwater sling removal device that performs underwater slinging of a sling wire used to suspend an underwater structure, and underwater acoustic communication equipment, wherein the underwater sling removal device has a sling removal mechanism comprising a 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 in a direction to insert and remove it relative to the pin holding plate, wherein the pin operating unit is arranged parallel to the locking pin and comprises an extension device equipped with a ball screw, and a connecting member that connects one end of the extension device and the locking pin, and the underwater acoustic communication equipment comprises a command information transmission device that transmits command information for the extension device as sound waves, and a machine control device that receives the command information transmitted as the sound waves from the command information transmission device and controls the extension device based on the command information, wherein the frequency band of the sound waves is set within the audible range. The underwater ball removal system of the present invention is also characterized in that the command information transmission device transmits the same command using multiple sound waves.

[0010] According to the underwater sling removal system of the present invention, a telescopic device equipped with a ball screw is used in the pin operating unit that moves the locking pin in the direction of insertion / removal relative to the pin holding plate. This allows the locking pin with the sling wire attached to be inserted / removed relative to the pin holding plate without the telescopic device malfunctioning due to water pressure. Therefore, it is possible to reliably perform the operation of removing the sling wire from the underwater structure installed underwater by simply operating the telescopic device.

[0011] In addition, because the telescopic device equipped with a ball screw does not cause problems such as oil leaks that can have a negative impact on the environment, which is a concern when using hydraulic telescopic devices, it can also be used in river construction and undersea construction.

[0012] Furthermore, by providing equipment for controlling the telescopic device equipped with a ball screw via wire or wirelessly, underwater workers can perform the ball removal work remotely, thereby improving safety and work productivity.

[0013] By using underwater acoustic communication equipment, the expansion device can be stably controlled and the ball removal work can be carried out even in work sites with various water environments, regardless of water quality, etc. Therefore, underwater workers such as divers can carry out their work safely while maintaining a certain distance from the underwater ball removal device.

[0014] Furthermore, if the frequency band of the sound waves is set within the audible range, the underwater worker can recognize that the ball removal work is being performed by the sound waves even in highly turbid water. Also, compared to using ultrasonic waves, which are generally used in underwater acoustic communication, the effects of the phenomenon of frequency band change caused by the relative speed difference between the transmitter and receiver, called Doppler shift, and the phenomenon of fluctuation in the reception strength of sound waves, called multipath fading, can be minimized. Therefore, it is possible to perform the ball removal work underwater using underwater acoustic communication equipment in a stable state.

[0015] Furthermore, since multiple signals are selected from within the audible range and used to transmit the same command signal into the sea as sound waves, when receiving sound waves, the signal that is least affected by various phenomena such as the above-mentioned Doppler shift and multipath fading, underwater noise, etc. can be selected and received to obtain command information. This makes it possible to further improve communication stability. Effect of the Invention

[0016] 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 attached to the sling wire in the direction of inserting and removing it from the pin holding plate.This makes it possible to efficiently perform sling removal work by remote control underwater, despite the simple configuration. [Brief description of the drawings]

[0017] [Figure 1] 1 is a diagram showing how an underwater structure is suspended using an underwater ball removal device in an embodiment of the present invention. FIG. [Diagram 2] 1 is a perspective view showing an underwater ball removal device according to an embodiment of the present invention; [Diagram 3] 1 is a side view of an underwater ball removal device according to an embodiment of the present invention. [Figure 4] 1 is a plan view of an underwater ball removal device according to an embodiment of the present invention. [Diagram 5] FIG. 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. [Figure 6] 1 is a diagram showing the behavior of an extension device and a locking pin in an embodiment of the present invention. FIG. [Figure 7] 3A and 3B are diagrams illustrating a control unit and an insertion / removal state confirmation sensor according to the embodiment of the present invention. [Figure 8] 1 is a diagram showing an outline of an underwater slinging system according to an embodiment of the present invention. FIG. [Figure 9] 1 is a diagram showing an outline of underwater acoustic communication equipment according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] The present invention is a device and system that can perform remote operation to remove the slings from an underwater structure equipped with a sling wire after the structure is installed underwater or landed on the bottom of the water, and can be used in any water environment such as the ocean, rivers, lakes, etc. The underwater structure can also be any type of scour prevention material such as riprap, or concrete blocks such as foot protection blocks or wave dissipating blocks (e.g., Tetrapods (registered trademark)).

[0019] In this embodiment, an example is taken of the use of an underwater load rotating device to carry out installation work for wave-dissipating blocks, which is one type of underwater civil engineering work, and the details of the underwater ball removal device and underwater ball removal system are described below with reference to Figures 1 to 9.

[0020] As shown in Figure 1, a hanging jig 5 is suspended in a horizontal position from a 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 hanging jig 5.

[0021] The underwater load rotation device 3 is a device for controlling the attitude of the suspended concrete block B, such as changing direction by rotating it and maintaining its attitude, and for making fine adjustments during positioning, underwater when installing the wave-dissipating block B on the seabed. In this type of underwater load rotation device 3, a suspension wire 3b is attached to the underside of the outer shell 3a, and a suspension jig 5 is suspended. Please refer to Japanese Patent No. 5970946 for the principle of attitude control by the underwater load rotation device 3.

[0022] The lifting jig 5 is made of H-shaped steel, and as shown in Fig. 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 an engaging eye 6a formed at one end that is directly connected to the lifting jig 5, and an engaged eye 6b formed at the other end, and this engaged eye 6b is attached to the underwater sling release device 1. Therefore, as shown in Fig. 1, after the wave-dissipating block B around which the sling wire 6 is looped hits the bottom in a predetermined position, the connection between the underwater sling release device 1 and the engaged eye 6b is released, and the sling wire 6 can be removed from the wave-dissipating block B.

[0023] <<Underwater ball removal device>> 3, the underwater ball removal device 1 includes a ball removal mechanism 10, an insertion / removal state confirmation sensor 20, a control unit 30, and a gauge 40 that houses these. The gauge 40 is formed by installing a wire mesh 42 on a substantially rectangular frame 41, but the shape is not limited to this.

[0024] <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.

[0025] The mounting portion 11 is formed in a substantially T-shape by a joining steel plate 111 in a lying position and an upright steel plate 112 placed on the upper surface of the joining steel plate 111. The joining steel plate 111 is placed on the ceiling of the gauge 40, and the upright steel plate 112 is placed so as to protrude upward from the gauge 40. The upright steel plate 112 is inserted between a pair of device mounting portions 5c provided on the lower flange 5a of the hanging jig 5, and is connected thereto via a connecting pin 5d. In addition, a pair of pin holding plates 12 are installed on the lower surface of the joining steel plate 111 at a predetermined interval in a position parallel to the upright steel plate 112.

[0026] As shown in the plan views of Figures 3 and 4, the pair of pin holding plates 12 are provided with opposing through holes 121. The locking pins 13 that move along guide tubes 131 are inserted removably into these through holes 121. In Figures 3 to 6, the right side of the paper surface is referred to as the removal side, and the left side of the paper surface is referred to as the insertion side.

[0027] The locking pin 13 is made of a long rod-shaped metal member, and is fitted with the locked eye 6b of the sling wire 6 arranged between the pair of pin holding plates 12. The guide tube 131 is connected coaxially with the through hole 121 to the outside of the pin holding plate 12a of the pair of pin holding plates 12 that is located on the side from which the locking pin 13 is pulled out. The operation of moving the locking pin 13 in the direction of insertion and removal is performed by the pin operating unit 14.

[0028] As shown in FIG. 4, the pin operating unit 14 includes a telescopic device 15, a coupling 16 connected to one end of the telescopic device 15, an underwater motor 17 connected to the telescopic device 15 via the coupling 16, and a connecting member 18 installed on the telescopic device 15.

[0029] The extension device 15 is arranged so as to extend and retract parallel to the insertion and removal direction of the locking pin 13, and any type of extension device, such as an electric type or a ball screw type, may be used as long as it has a mechanism suitable for use underwater.

[0030] Examples of mechanisms that are unsuitable for use underwater include hydraulically and pneumatically driven telescopic mechanisms. Hydraulically driven telescopic mechanisms may cause oil leaks and other adverse environmental effects, making them unsuitable for use in rivers or the ocean. Pneumatically driven telescopic mechanisms may not only malfunction due to water pressure when used underwater, but also require separate air compressors and other equipment, which can result in excessively large auxiliary equipment and are therefore not suitable for use underwater.

[0031] Below, a ball screw is taken as an example of a telescopic mechanism suitable for use underwater, and an example of a telescopic device 15 using a ball screw will be described with reference to FIG.

[0032] The telescopic device 15 includes a screw shaft 151, a ball nut 1521, a hollow rod 152 incorporating the ball nut 1521, and a protective tube 153 for housing the screw shaft 151 and the hollow rod 152.

[0033] The screw shaft 151 is allowed to rotate freely about its axis, and its shaft portion 1512 on the base end side is supported by a centralizer 1531 provided in a protective tube 153. A ball nut 1521 provided inside the hollow rod 152 is screwed onto the threaded portion 1511 formed from the middle portion toward the tip side. The screw shaft 151 having this configuration is rotated by power supply from the underwater motor 17.

[0034] The submersible motor 17 is disposed such that its output shaft 171 intersects with 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 capable of transmitting power via orthogonal or skewed shafts.

[0035] When the shaft portion 1512 of the screw shaft 151 and the output shaft 171 of the submersible motor 17 are arranged to form what is called a skew shaft, the coupling 16 may be provided 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 portion 1512 of the screw shaft 151. In this manner, power can be smoothly transmitted from the output shaft 171 of the submersible motor 17 to the shaft portion 1512 of the screw shaft 151.

[0036] When the two are in a perpendicular axis relationship, a suitable gear such as a straight bevel gear or a spiral bevel gear may be used. By arranging the two in a staggered or perpendicular axis relationship in this way, the width of the gauge 40 can be made shorter and smaller than when they are arranged in series, and the underwater ball removal device 1 as a whole can be made slimmer.

[0037] The worm 161 and the worm wheel 162 are housed in a highly waterproof and pressure-resistant housing 163. The protective tube 153 of the telescopic device 15 described above is fixed to the housing 163, and the protective tube 153 and the hollow rod 152 that appears and retracts from it are also highly waterproof and pressure-resistant, just like the housing 163.

[0038] As shown in Fig. 3, the above-mentioned coupling 16 is fixed to a support column 164 suspended from the ceiling of the gauge 40 and is disposed on the insertion side of the locking pin 13. As a result, in the telescopic device 15, the screw shaft 151 connected to the coupling 16 is disposed on the insertion side, and the hollow rod 152 is disposed on the extraction side. The connecting member 18 is connected to this hollow rod 152.

[0039] The connecting member 18 is provided perpendicular to the hollow rod 152 and the locking pin 13, as shown in Fig. 4, to connect them together. Therefore, as shown in Fig. 6(b), when it is desired to pull out the locking pin 13 to which the sling wire 6 is attached from the through hole 121 of the pair of pin holding plates 12, the screw shaft 151 is rotated so that the hollow rod 152 moves to the pulling side, thereby extending the telescopic device 15. As a result, as shown in Fig. 6(a), the locking pin 13 is pulled out from the pair of pin holding plates 12 and the sling wire 6, and the sling removal operation is completed.

[0040] On the other hand, 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 slinging wire 6 arranged between them as shown in Fig. 6(a), 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 Fig. 6(b), the locking pin 13 is inserted into the pair of pin holding plates 12 and the slinging wire 6. An insertion / removal state confirmation sensor 20 is provided in the gauge 40 so that such an insertion / removal state can be recognized by a person at a distance.

[0041] <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.

[0042] The insertion detection sensor 21 is provided on the outer side of the pin holding plate 12b, which is located on the insertion side of the locking pin 13, of the pair of pin holding plates 12, directly above the through hole 121. The removal detection sensor 22 is provided directly above the removal end of the locking pin 13 in a state where 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 may be any shape, and it is also not necessary to use the installation jig 23 for attachment.

[0043] Non-contact magnetic proximity sensors are used for the insertion detection sensor 21 and removal detection sensor 22. 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.

[0044] The insertion / removal state confirmation sensors 20 arranged on these gauges 40 are connected to the control unit 30 together with the underwater motor 17. Note that the insertion / removal state confirmation sensor 20 is not limited to this, and other sensors can be used as long as they are capable of detecting the locking pin 13 underwater.

[0045] <Control Unit> The control unit 30 is installed in the gauge 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 housing these.

[0046] The pressure-resistant container 33 has a connection panel 331 attached to its outer surface, and as shown in Fig. 7, is provided with a sensor jack 331a and a motor jack 331b for connecting the motor driver 31 and the battery 32 to the insertion / removal state confirmation sensor 20 and the underwater motor 17. The connection panel 331 is also provided with 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.

[0047] As a result, the underwater motor 17 is controlled by the motor driver 31 to operate the telescopic device 15. When the locking pin 13 is pulled out of the through hole 121 by operating the telescopic device 15, the pull-out detection sensor 22 detects the locking pin 13 and causes the pull-out detection light 331c to flash.

[0048] 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 the outside of the gauge 40.

[0049] This allows the underwater worker D and the surface worker S to check the insertion / removal state of the locking pin 13 while remotely standing from the underwater ball removal device 1, as shown in Figure 1. When the insertion detection sensor 21 and the removal detection sensor 22 detect the locking pin 13, they send a detection signal to the motor driver 31. The motor driver 31, having received the detection signal, stops the underwater motor 17.

[0050] 7, the connection panel 331 is provided with a power jack 331e. When the power plug 34 is inserted into the power jack 331e, the power switch is turned on and the underwater ball release device 1 becomes usable. When the power plug 34 is removed and a charging cable (not shown) is attached, the battery 32 can be charged. When the underwater ball release device 1 is not in use, a dummy plug (not shown) is attached.

[0051] Furthermore, the connection panel 331 is provided with a wired controller jack 331f and a wired controller 35 attached thereto. The wired controller 35 is used to manually operate the submersible motor 17 and may take any form, but is set, for example, so that the submersible motor 17 rotates forward when the handle 351 is turned to the right and rotates reversely when turned to the left. This makes it possible to move the locking pin 13 in the insertion / removal direction as appropriate by extending and retracting the extension device 15.

[0052] In this way, the underwater ball release device 1 can be operated by 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 and underwater acoustic communication equipment, taking the case of using underwater acoustic communication technology as an example.

[0053] <<Underwater ball removal system>> 8 and 9, the underwater ball removal system 100 includes the above-mentioned underwater ball removal device 1 and underwater acoustic communication equipment 2. The underwater acoustic communication equipment 2 includes a command information transmitting device 50 that transmits command information M to the underwater ball removal device 1 by the surface worker S as sound waves, and a machine control device 60 that receives the sound waves and controls the underwater ball removal device 1 based on the command information M.

[0054] Below, an overview of the command information transmission device 50 and the machine control device 60 will be described, but for details, please refer to Japanese Patent Application No. 2019-192086. In this embodiment, the command information M is "extension" and "contraction". "Extension" is a command to extend the extension device 15 so as 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 so as to insert the locking pin 13 into the through hole 121 of the pair of pin holding plates 12.

[0055] <Command information transmission device> As shown in FIG. 9, the command information transmitting device 50 includes a command input unit 51, an oscillator 52, a carrier wave selector 53, a modulator 54, an amplifier 55, and a wave transmitter 56.

[0056] The command input unit 51 includes an input section into which the surface worker S or the underwater worker D inputs an operation command for the extension device 15 in the underwater ball removal device 1. The input section is provided with at least two operation command buttons, "extend" and "retract." The surface worker S or the underwater worker D inputs an operation command 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 becomes a baseband signal, and outputs it to the modulation unit 54.

[0057] Meanwhile, the oscillator 52 creates a plurality of reference waves W to be used as carrier waves C, and outputs these to a carrier selection unit 53. The carrier selection unit 53 selects two or more reference waves W to be used as carrier waves C from the plurality of reference waves W, and outputs them to a modulation unit 54 that is connected wirelessly or via a wire.

[0058] The modulation unit 54 performs so-called modulation, in which the command information M input from the command input unit 51 is mixed with each of the two or more carrier waves C input from the carrier wave selection unit 53, to form a plurality of modulated waves Mw having different frequency bands. The plurality of 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 the carrier waves C by changing the phase without changing their frequency and amplitude.

[0059] 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, which is a transducer dedicated to wave transmission, 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 placed in the air or may be suspended in the water as shown in Fig. 8.

[0060] These multiple types of sound waves transmitted into the sea may be transmitted at different times, or may be combined and transmitted simultaneously. Note that the sound waves transmitted from the transmitter 56 are modulated waves Mw by D / A conversion, and the modulated waves Mw are carrier waves C modulated by the BPSK method, so that the frequency band is the same as that of the carrier waves C.

[0061] <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.

[0062] The receiver 61 is a dedicated receiver transducer that collects various underwater sound waves and converts them into an input electrical signal Ms' through A / D conversion, and in this embodiment, a hydrophone capable of handling the audible range is used. The sound waves collected by these receivers 61 are multiple types of sound waves based on multiple modulated waves Mw transmitted from the transmitter 56. As shown in Fig. 8, multiple receivers 61 are provided on the gauge 40, and the position and number of such receivers 61 may be any position that allows easy reception of sound waves.

[0063] The frequency diversity unit 62 continuously analyzes the quality of the input electrical signal Ms' by using the carrier frequency bands of the multiple carrier waves C selected by the carrier selection unit 53 of the command information transmission device 50 and the frequency bands of the harmonics of the carrier waves C. Note that a harmonic refers to a waveform whose frequency is an integer multiple of the fundamental frequency waveform. Of the input electrical signal Ms', the most reliable signal originating 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 an amplifier 63 connected by wire or wirelessly.

[0064] The amplifier 63 amplifies the processed electrical signal Ms corresponding to the modulated wave Mw or its harmonics, and outputs the signal to a wired or wirelessly connected demodulator 64. The demodulator 64 demodulates the amplified processed electrical signal Ms, acquires command information M relating to the operation command inputted by the command input unit 51 of the command information transmission device 50, and outputs the command information M 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.

[0065] As described above, the underwater payload removal system 100 utilizes the underwater acoustic communication equipment 2 to transmit into the sea the operation commands of the surface worker S or the undersea worker D for the extension joint 15 of the underwater payload removal device 1, which are input to the command information transmission device 50, as command information M. In addition, by receiving this information with the machine control device 60, it becomes possible to control the operation of the extension joint 15 based on the command information M.

[0066] In this embodiment, three types (2 kHz, 2.25 kHz, 2.5 kHz) are selected from the audible range (generally between 20 Hz and 20 kHz) by the carrier wave selection unit 53, 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, it becomes possible for the underwater worker D to recognize from the sound waves that the ball removal work is being performed even in highly turbid water.

[0067] 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 multipath fading, in which the received strength of sound waves fluctuates.

[0068] 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, so that when receiving the sound waves, the one least affected by various phenomena such as the above-mentioned Doppler shift and multipath fading, underwater noise, etc. is selected and received, and command information M can be obtained. This makes it possible to further improve communication stability.

[0069] <<How to install concrete blocks using an underwater ball removal system>> A specific procedure for installing the wave-dissipating block B on the seabed using the underwater ball removal system 100 having the above-mentioned configuration will be described below.

[0070] After the battery 32 provided in the control unit 30 of the underwater ball removal device 1 has been charged in advance, the power plug 34 is inserted into the power jack 331e provided on the connection panel 331 of the control unit 30, as shown in FIG.

[0071] At the same time, the hoisting jig 5 is suspended from the underwater load rotating device 3 suspended from the wire 4b of the crane 4a mounted on the crane ship 4. As shown in Fig. 2, a sling wire 6 is connected to one end of the lower flange 5a of the hoisting jig 5 via a locking eye 6a, and the underwater sling release device 1 is installed on the other end. The sling wire 6 is then looped around a wave dissipating block B placed on the ground, and the locked eye 6b of the sling wire 6 is placed between a pair of pin holding plates 12 provided on the sling release mechanism 10, as shown in Fig. 6(a).

[0072] After that, as shown in Fig. 6(b), the locked 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 a case where the wired controller 35 is used for operation, first, the locked 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 the side that shortens the telescopic device 15).

[0073] Then, a control signal is sent from the wired controller 35 to the motor driver 31, and the extension device 15 is shortened by the power supply from the underwater motor 17. As a result, the locking pin 13 connected to the extension device 15 via the connecting member 18 moves to the side where it is inserted into the through holes 121 of the pair of pin holding plates 12, so that the sling wire 6 is attached to the locking pin 13 as shown in Figure 6(b).

[0074] 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 transmits a detection signal to the insertion detection light 331d and the motor driver 31. As a result, the insertion detection light 331d lights up to notify that the locking pin 13 has been inserted, and the motor driver 31 stops the underwater motor 17 to stop the retracting operation of the telescopic device 15.

[0075] After that, while lifting the underwater hoisting and rotating device 3 and the hoisting jig 5 with the crane 4a, it is confirmed that the wave-dissipating block B can be lifted in a stable state, and then the crane 4a is operated to lift and lower the wave-dissipating block B to a desired position in the sea. In addition, after adjusting the direction and posture of the wave-dissipating block B using the underwater hoisting and rotating device 3, the wave-dissipating block B is installed on the seabed.

[0076] After confirming that the wave-dissipating block B has hit the bottom, underwater worker D operates the “extend” operation command button on the command input section 51 of the command information transmission device 50, and transmits the “extend” command information as sound waves to the machine control device 60.

[0077] When the machine control device 60 receives the "extend" command information, a control signal is sent from the control unit 65 to the motor driver 31, and the telescopic device 15 is extended by the power supply from the underwater motor 17. As a result, the locking pin 13 connected to the telescopic device 15 via the connecting member 18 moves to the side where it is pulled out from 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).

[0078] After the sling removal work is completed in this manner, the sling wire 6, the hoisting jig 5, and the underwater hoisting and rotating device 3 are lifted up and removed by the crane 4a. This type of work is repeated until all the wave-dissipating blocks B are installed on the seabed.

[0079] As described above, with the underwater sling removal 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, by simply operating the extension device 15, it is possible to reliably perform the sling removal work of the sling wire 6 from the wave dissipating block B installed underwater underwater.

[0080] Moreover, according to the underwater payload removal system 100, since the underwater acoustic communication equipment 2 is used, the telescopic device 15 can be stably controlled and the payload removal work can be performed even in work sites with various water environments regardless of the water quality, etc. Therefore, the underwater worker D can safely perform the work while maintaining a certain distance from the underwater payload removal device 1. Furthermore, since the frequency band of the sound waves is set within the audible range, the underwater worker D can recognize that the payload removal work is being performed by the sound waves even in highly turbid water.

[0081] The above-mentioned embodiment is for the purpose of facilitating understanding of the present invention, and is not intended to limit the present invention. The present invention can be modified or improved without departing from the spirit of the present invention, and it goes without saying that the present invention includes equivalents thereof.

[0082] For example, in this embodiment, the underwater ball release system 100 is configured to include the 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 about underwater visible light communication technology, see, for example, Japanese Patent No. 5970946.

[0083] In this embodiment, the inserted / removed state of the locking pin 13 relative to the pair of pin holding plates 12 is detected using the inserted / removed 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.

[0084] Furthermore, in this embodiment, the inserted / removed state of the locking pin 13 is confirmed by the inserted / removed state confirmation sensor 20, and the information is notified by the removal detection light 331c and the insertion detection light 331d so that it can be visually recognized, but this is not limited to this, and for example, a device that provides auditory recognition may be adopted. [Explanation of symbols]

[0085] 1 Underwater ball removal device 2 Underwater acoustic communication equipment 3. Underwater load rotation device 3a Outer shell 3b Suspension wire 4 Hoist ship 4a Crane 4b Wire 5 Hanging jig 5a Lower flange 5b Upper flange 5c Pair of device mounting parts 5d Connecting pin 6. Sling Wire 6a Locking eye 6b Locking eye 10 Ball removal mechanism 11 Mounting part 111 Joined steel plate 112 Erect steel plate 12 Pair of pin retaining plates 121 Through hole 13 Locking pin 131 Guide tube 14 pin working unit 15 Telescopic device 151 Screw shaft 1511 Threaded part 1512 Shaft 152 Hollow Rod 1521 Ball nut 153 Protective tube 1531 Centralizer 16 Coupling 161 Warm 162 Worm Wheel 163 Housing 164 Support column 17 Underwater Motor 171 Output shaft 18 Connecting members 20 Insertion / removal status sensor 21 Insertion detection sensor 22 Pull-out detection sensor 23 Installation jig 30 Control Unit 31 Motor Driver 32 Battery 33 Pressure vessels 331 Connection Panel 331a Sensor Jack 331b Motor Jack 331c Pull-out detection light 331d Plug-in detection light 331e Power 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 section 52 Oscillator 53 Carrier wave selection unit 54 Modulation section 55 Amplifier 56 Transmitter 60 Machine Control Device 61 Receiver 62 Frequency diversity section 63 Amplifier 64 Demodulation section 65 Control Unit B Wave-dissipating blocks (underwater structures) C Carrier M command information W reference wave Mw Modulation wave Ms' Input electrical signal Ms processed electrical signal S Water worker D Underwater workers

Claims

1. An underwater lifting system including an underwater lifting device and underwater acoustic communication equipment for lifting and releasing a sling wire that suspends an underwater structure underwater, The underwater ball removal device is A sling removal mechanism includes a 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, The pin operating unit includes: An extension device arranged in parallel with 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 underwater acoustic communication equipment includes: A command information transmitting device that transmits command information for the telescopic device as sound waves; a machine control device that receives the command information transmitted as the sound wave from the command information transmission device and controls the telescopic device based on the command information, An underwater ball removal system, characterized in that the sound waves have a frequency band set within the audible range.

2. 2. The underwater ball removal system according to claim 1, An underwater ball removal system, wherein the command information transmission device transmits the same command using multiple sound waves.

Images