JP2011058167A - Dredging unit and dredging method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dredging unit and a dredging method which can smooth a slope which is liable to be formed in a staircase pattern when dredging is performed on the slope, and can reduce the excessive break of the slope during the excavation of the slope. <P>SOLUTION: The dredging unit is equipped with a grab bucket 1 which includes a pair of bucket shells 3 and 4 joined to each other in such a manner as to be rotatable about a supporting shaft, so that it can perform horizontal excavation. When the slope is dredged on the bottom of the water by using the grab bucket, the slope is excavated in a state that the bucket shell is obliquely and adjusted in terms of position so that a center line of the supporting shaft can be inclined from a horizontal direction depending on an angle of the inclination of the slope. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a dredge apparatus and a dredge method using a horizontal excavation grab bucket.

  Grab dredging is a method that excavates the bottom sediment with a grab bucket suspended from a dredger by a crane, and raises and lowers the grab bucket to drown the bottom sediment. According to the conventional grab dredging method, there is a problem that the excavation during excavation is large, the sediment overflows, the polluted water easily diffuses, and the bottom shape after excavation becomes uneven. On the other hand, a grab dredging method has been developed in which a contaminated portion accumulated on the upper part of the bottom of the water is excavated horizontally with a grab bucket to enable thin layer dredging.

  Two conventional horizontal excavation methods will be described with reference to FIGS. The first conventional example of FIG. 9 uses a horizontal excavation grab bucket (see Patent Document 1), and the second conventional example of FIG. 10 performs horizontal excavation using a normal grab bucket (see FIG. 9). Patent Document 2).

  A grab bucket 100 shown in FIGS. 9 (a) and 9 (b) includes a pair of bucket shells 101 and 102 that open and close about a support shaft 103, and the bucket shells 101 and 102 are elevating chains at outer connection portions 101b and 102b. 103, 104, the lifting chains 103, 104 are joined at the upper joint 106, the joint 106 is connected to a wire 107 from a crane (not shown), and the bucket shell 101, 102 moves up and down. Further, an opening / closing wire 105 from the crane is connected to the support shaft 103 for opening / closing the bucket shells 101, 102, and the bucket shells 101, 102 are opened / closed by raising / lowering the opening / closing wire 105.

  When the length from the connecting portions 101b and 102b of the elevating chains 103 and 104 to the blade tips 101a and 102a of the bucket shells 101 and 102 raises and lowers the support shaft 103 with the opening and closing wire 105, the locus of the blade tips 101a and 102a is The length can be moved in the horizontal direction while moving up and down within a predetermined height range. For this reason, when the bucket shells 101 and 102 are opened and closed by raising and lowering the opening and closing wire 105, the locus of the blade edges 101a and 102a moves in the horizontal direction while moving up and down within a predetermined height range so that excavation is possible.

  According to the dredging method using the horizontal excavation grab bucket of FIG. 9, thin layer dredging is possible, the polluted portion accumulated on the upper part of the bottom of the water can be excavated horizontally, there is no sediment overflow, and there is no pollution underwater diffusion. Can be realized.

  The grab bucket 150 shown in FIG. 10 has a support wire 156 connected to a support body 155, and a pair of arms 153 and 154 are rotatably supported by arm support shafts 158 at both ends of the support body 155. The buckets 151 and 152 are rotatably supported by a bucket support shaft 159 at the lower end of 154. Buckets 151 and 152 are rotatably connected to pulley mechanism 160 by connecting shaft 161, and rotate in conjunction with pulley mechanism 160 by opening / closing wire 157. When the opening / closing wire 157 is extended, the pair of buckets 151 and 152 are opened to the left and right. The opening / closing angle of the buckets 151, 152 is defined by the amount of the opening / closing wire 157 being drawn in and out. The feed-in amount of the elevating wire 156 and the feed-in amount of the opening / closing wire 157 are detected, and the blade edge positions 151a and 152a in the side surface direction of the bucket are calculated from these detection data by the data processing device, and the calculated side surface of the bucket The movement trajectories of the blade edge positions 151a and 152a in the direction are displayed on the monitor in real time, and the operator can adjust the blade edge positions 151a and 152a and move them horizontally while watching the movement locus of the blade edge positions 151a and 152a. The bottom of the water can be flattened.

JP 2005-264606 A JP 2006-27830 A

  When dredging on the slope where the bottom G of FIG. 11 is inclined, the design cross section is basically obtained by digging in the design as shown in FIG. 11 using the grab bucket as shown in FIG. 9 and FIG. Create a satisfactory slope. However, according to the conventional dredging method, step digging is performed on a design cross section having a straight cross section as shown in FIG. 11, so that the slope digging becomes large as shown by hatching in FIG. 11. In addition, the shape of the slope becomes stepped.

  In view of the above-described problems of the prior art, the present invention can smooth a slope that tends to be stepped when sloped on a slope, and can reduce over-excavation during slope digging. An object is to provide an apparatus and a dredge method.

  In order to achieve the above object, a dredge apparatus according to the present invention includes a grab bucket configured to enable horizontal excavation from a pair of bucket shells joined so as to be rotatable about a support shaft, and the grab bucket When drilling the slope at the bottom of the water using the slope, drill the slope with the bucket shell positioned at an angle so that the centerline of the support shaft tilts from the horizontal direction according to the slope angle of the slope. By doing so, it is possible to realize smoothing of the slope and reduction of the slope digging.

  That is, the dredge apparatus according to the present embodiment is a dredge apparatus including a grab bucket capable of horizontal excavation, an elevating means for elevating the grab bucket, and an opening / closing means for performing an opening / closing operation of the grab bucket. The grab bucket includes a pair of bucket shells joined so as to be rotatable about a support shaft, and suspension means for hanging the bucket shell, and the lifting means is moved up and down by the lifting means. The bucket shell is raised and lowered, the bucket shell is opened and closed by an up and down operation by the opening and closing means, and the hanging means is supported by a lifting member supported by the raising and lowering rope member of the lifting and lowering means, and the hanging member A pair of suspension rope members disposed between the member and the bucket shell, and the suspension rope members based on the inclination angle of the slope to be anchored. Suspension length adjustment means capable of adjusting the length of the suspension, and the suspension means adjusts the suspension length of one of the suspension rope members by the suspension length adjustment means. The bucket shell can be suspended obliquely so that the center line of the support shaft is inclined from the horizontal direction.

  According to this dredging device, a pair of bucket shells constituting a grab bucket capable of horizontal excavation can be suspended obliquely so that the center line of the support shaft is inclined from the horizontal direction. Based on the inclination angle of the slope, the blade edge of each bucket shell can be disposed substantially parallel to the slope. For this reason, it is possible to smooth the slope that is likely to be stepped when dredging on the slope, and to reduce the surplus slope during the slope excavation.

  In the above dredging apparatus, it is preferable that the suspension length adjusting means includes a suspension length adjusting rope member disposed between any one of the suspension rope members and the suspension member. By changing the length of the rope member for adjusting the suspension length, it is possible to cope with a change in the inclination angle of the slope of the heel object.

  Further, two of the pair of suspension rope members are connected in the vicinity of both corners of one end of the pair of bucket shells with the support shaft interposed therebetween, and the other is connected to the pair of buckets with the support shaft interposed therebetween. It is preferable that two are connected in the vicinity of both corners of the other end of the shell, and are connected to the suspension member and the suspension length adjusting rope member at one place respectively.

  In addition, it is preferable that the said suspension member and the said support shaft are arrange | positioned so that the axis | shaft extended in the horizontal direction of the said suspension member and the centerline of the said support shaft may pass the surface of the same perpendicular direction.

  In addition, when the pair of bucket shells are rotated about the support shaft by the opening / closing means by the opening / closing means and opened / closed, the locus of the blade edge of each bucket shell moves horizontally with the height position being substantially constant. It is configured.

  The dredging method according to the present embodiment is a dredging method for dredging a slope at the bottom of a water using a grab bucket that includes a pair of bucket shells that are pivotally joined around a support shaft and is capable of horizontal excavation, The beveling is performed with the bucket shell being obliquely adjusted so that the center line of the support shaft is inclined from the horizontal direction based on the inclination angle of the slope.

  According to this dredging method, since the grab bucket is slanted so that the center line of the support shaft is inclined from the horizontal direction, it can be arranged obliquely with respect to the slope based on the inclination angle of the slope to be dredged. The entire cutting edge of the shell can be arranged substantially parallel to the slope. For this reason, it is possible to smooth the slope that is likely to be stepped when dredging on the slope, and to reduce the surplus slope during the slope excavation.

  In the scissor method, the pair of bucket shells are configured to open and close by pivoting about the support shaft, and the trajectory of the blade edge of each bucket shell is horizontal while the height position is substantially constant during the opening and closing. Is configured to move.

  According to the dredging apparatus and dredging method of the present invention, it is possible to smooth the slope that tends to be stepped when dredging on the slope, and to reduce the surplus slope during the slope excavation.

It is a front view which shows schematic structure of the grab bucket of this embodiment. It is the front view (a) which shows the state which the bucket shell of FIG. 1 opened, the front view (b) which shows the half-opened state, and the front view (c) which shows the closed state. It is the side view (a) and front view (b) which show the grab bucket of the open state of the dredge apparatus by this embodiment. It is the side view (a) and front view (b) which show the grab bucket of a closed state. It is the figure which looked at the inside of the open grab bucket similar to FIG.3 (b) from the front. It is a figure which shows process (a)-(e) of the horizontal excavation construction method using the grab bucket of FIGS. It is a perspective view shown in the state which suspended the grab bucket of the open state of FIGS. 3-6 diagonally. It is a side view which shows the grab bucket (closed state) of FIG. It is the side view (a) and front view (b) of the grab bucket used for the horizontal excavation construction method of the 1st conventional example. It is a side view of the grab bucket of the 2nd prior art example. It is sectional drawing of the water bottom for demonstrating the problem of the slope by a prior art.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. The grab bucket of this embodiment is configured so that the trajectory of the blade edge of each bucket shell moves horizontally when a pair of bucket shells open and close, similar to the grab bucket of FIG. 9, but the bucket shell is suspended. The configuration is different.

  First, with reference to FIGS. 1 and 2, a configuration in which the locus of the blade tips of a pair of bucket shells moves horizontally when opening and closing will be described. FIG. 1 is a front view showing a schematic configuration of the grab bucket of the present embodiment. 2 is a front view (a) showing a state where the bucket shell of FIG. 1 is opened, a front view (b) showing a half-open state, and a front view (c) showing a closed state.

  As shown in FIG. 1, the grab bucket 1 includes a pair of steel bucket shells 3 and 4 that pivot about a support shaft 2 to open and close, and suspension wires 5 and 6 that suspend the bucket shells 3 and 4, An opening / closing wire 7 which is an opening / closing means for opening / closing the bucket shells 3, 4. The bucket shells 3 and 4 are joined by the support shaft 2, and an opening / closing wire 7 is joined to the support shaft 2, and two suspension wires 5 and 6 extending from the suspension wire 9 to the left and right are attached to the bucket shells 3 and 4. Connected to the outer edge. The length ab from the connecting portion of the suspension wires 5 and 6 to the blade tips 3a and 4a of the bucket shell is the length that the locus of the blade tips 3a and 4a can move horizontally when the support shaft 2 is raised and lowered by the opening and closing wire 7. There is little change in the height position of the trajectory at this time. For this reason, according to the grab bucket 1, when the bucket shells 3 and 4 are opened and closed by raising and lowering the opening and closing wire 7, the trajectories of the blade edges 3a and 4a move horizontally, thereby enabling horizontal excavation at the bottom of the water.

  The trajectories of the blade edges 3a and 4a of the bucket shells 3 and 4 when the bucket shells 3 and 4 are opened and closed will be examined with reference to FIGS. 1 and 2A to 2C. Such examination is disclosed in the above-mentioned Patent Document 1 by the present applicant.

  The coordinates (X, Y) of the blade edges 3a, 4a of the grab bucket 1 of FIG. 1 can be expressed by the following equations (1), (2).

X = msinθ _x + absin ψ _x (1)
Y = m cos θ _x + abcos φ _x (2)
However, the length of m hanging wires 5,6, theta _x is hanging wires 5, 6 and the angle between the Y-axis, ab is suspended from the connection of the wires 5,6 of the bucket shell edge 3a, to 4a long Ψ _x is an angle formed by the line segment ab and the Y axis. The point c (the center of the support shaft 2) is always X = 0.

The Y coordinate of the blade edges 3a and 4a is obtained from the above equation (2). For example, when the grab bucket 1 is manufactured with the dimensions m = 3099 mm, ab = 877 mm, bc = 1969 mm, and ca = 1666 mm, θ _{x in the} state where the bucket shells 3 and 4 are opened as shown in FIG. Since = 32.3 ° and ψ _x = −6.8 °, when the Y coordinate is obtained from the equation (2), Y = 3099 × cos32.3 ° + 877 × cos (−6.8 °) = 3490 mm (solution 1).

Further, as shown in FIG. 2B, when the bucket shells 3 and 4 are half opened by raising the opening / closing wire 7, θ _x = 27.66 ° and ψ _x = 23.15 °. 3099 × cos27.66 ° + 877 × cos23.15 ° = 3551 mm (solution 2). Similarly, when the bucket shells 3 and 4 are closed by further raising the opening / closing wire 7 as shown in FIG. 2C, θ _x = 13.7 ° and ψ _x = 57.1 °, so Y = 3099 × cos13.7 ° + 877 × cos57.1 ° = 3487 mm (solution 3)

  Comparing solutions 1-3 above, 3490mm (solution 1)-3487mm (solution 3) = 3mm, 3490mm (solution 1)-3551mm (solution 2) = -61mm, and 3487mm (solution 3)-3551mm ( Solution 2) = − 63 mm. From this result, it was confirmed that the blade edges 3a and 4a move horizontally while moving within a height distance of 65 mm when the bucket shells 3 and 4 are opened and closed by raising and lowering the opening and closing wire 7.

  As described above, according to the grab bucket 1 shown in FIG. 1, the heights of the blade edges 3a and 4a are kept substantially constant by determining the length ab and the like so that the Y coordinate according to the equation (2) is constant. It is possible to design the bucket shells 3 and 4 that are kept horizontal.

  Next, the configuration of the dredge apparatus according to the present embodiment will be described with reference to FIGS. FIG. 3 is a side view (a) and a front view (b) showing the grab bucket in the open state of the dredge apparatus according to the present embodiment. FIG. 4 is a side view (a) and a front view (b) showing the closed grab bucket. The grab buckets of FIGS. 3 and 4 have the same basic configuration as the grab bucket of FIG.

  3 and 4 is a glove bucket 1 having a pair of steel bucket shells 3 and 4 that pivots around a support shaft 2 to open and close, and the bucket shells 3 and 4 are suspended and moved up and down. Elevating means including elevating chains 15 and 16 and a suspension member 11 held horizontally, and opening / closing means including opening / closing wires 7 for opening and closing the bucket shells 3 and 4 are provided. The opening / closing wire 7 mainly bears the hoisting load of the grab bucket 1 when the grab bucket 1 is closed and ascends. At this time, the lifting chains 15 and 16 prevent the grab bucket 1 from rotating on the horizontal plane. Is wound up in synchronism with the opening / closing wire 7.

  The pair of bucket shells 3 and 4 rotate around the support shaft 2 by moving the pulling wire 7 upward and pulling it from the state where it is opened 180 degrees as shown in FIGS. It will be in the closed state like 4 (a) (b). Further, by loosening the opening / closing wire 7 from the closed state shown in FIGS. 4A and 4B and moving it downward, the bucket shells 3 and 4 are rotated and opened by their own weight.

  As shown in FIG. 3A, elevating chains 15 and 16 are connected to both ends of the center line p of the support shaft 2 extending in the horizontal direction, and as shown in FIG. 15 is connected to a position away from the support shaft 2 at the upper part of the bucket shell 3, and a lifting chain 16 is connected to a position away from the support shaft 2 at the upper part of the bucket shell 4.

  Above the bucket shells 3 and 4, a rod-like suspension member 11 made of a shape steel or the like is disposed so as to extend in a horizontal direction substantially parallel to the center line p of the support shaft 2, as shown in FIG. Two elevating chains 15 and 16 are connected to the end of the suspension member 11 at a single location in a substantially Δ (delta) shape to form a delta portion.

  Lifting wires 12 and 13 are connected to both ends of the upper part of the suspension member 11, and the bucket shells 3 and 4 are suspended horizontally at the four corners by the lifting chains 15 and 16 via the suspension member 11. By raising and lowering the elevating wires 12 and 13 or the opening and closing wire 7, the bucket shells 3 and 4 are raised and lowered via the suspension member 11 and the elevating chains 15 and 16.

  Next, an opening / closing mechanism for the bucket shells 3, 4 by the opening / closing wire 7 will be described with reference to FIG. FIG. 5 is a front view of the inside of the open grab bucket similar to FIG. 3 (b).

  As shown in FIG. 5, the opening / closing mechanism of the bucket shells 3 and 4 includes an upper pulley 17 in which an opening / closing wire 7 is provided at the upper portion of the bucket shell 3, a lower pulley 18 provided at the lower portion of the bucket shell 3, and the bucket shell 4. The lower pulley 19 provided at the lower portion of the bucket shell 4 is stretched over and joined to the upper pin 20 of the bucket shell 4. When the opening / closing wire 7 is pulled upward, the support shaft 2 is pushed upward by this pulling force, and the bucket shells 3 and 4 rotate about the support shaft 2 as shown in FIGS. 4 (a) and 4 (b). Closed state. Further, when the pulling force of the opening / closing wire 7 is loosened from this closed state, the bucket shells 3 and 4 are rotated by the weight of the bucket shells 3 and 4 so as to be in the open state shown in FIGS. Become.

  The open / close wire 7 can be wound and unwound via a crane by a winch (not shown) of the dredger hoist ship, and the bucket shells 3 and 4 can be rotated to open and close and the grab bucket 1 can be wound up. . Similarly, the elevating wires 12 and 13 can be wound and lowered via a crane by two winches (not shown) that are rotationally driven synchronously, and move up and down together with the grab bucket 1. For this reason, it is preferable to use a hoist ship having a grab bucket opening / closing main winch at the center and a grab bucket lifting winch on both sides of the hoist ship bridge.

  Next, the horizontal excavation dredging process by the dredge apparatus of FIGS. 1-5 is demonstrated with reference to FIG. FIG. 6 is a diagram illustrating steps (a) to (e) of the horizontal excavation dredging method using the grab buckets of FIGS.

  First, with the bucket shells 3 and 4 opened at 180 degrees as shown in FIG. 3, the lifting wires 12 and 13 of FIGS. 3 and 4 are lowered to submerge the grab bucket 1 and lowered to the design dredging depth, It installs in the bottom G as shown in FIG. At this time, no load is applied to the open / close wire 7 yet.

  Next, when the pulling-up of the opening / closing wire 7 is started, the suspension load gradually moves to the opening / closing wire 7, and at the same time, the grab bucket 1 is supported by the bucket shells 3, 4 as shown in FIG. When the opening / closing wire 7 is further lifted with the shaft 2 as the center, the bucket shells 3 and 4 are further rotated in the closing direction as shown in FIGS.

  In the process of closing the bucket shells 3, 4, the blade edges 3 a, 4 a of the bucket shells 3, 4 move horizontally with the height position being substantially constant, and the earth and sand D of the bottom G is horizontally excavated. Move to the inside of 4. Finally, as shown in FIG. 6 (e), the bucket shells 3 and 4 are further rotated in the closing direction to close the earth and sand D held inside. In addition, the raising / lowering wires 12 and 13 are not moved in the process of FIG.6 (b)-(e).

  Next, the grab bucket 1 is lifted from underwater by winding up the opening and closing wire 7 of FIGS. 3 and 4 and moved to a sediment transport ship (not shown), and then opened, and the internal sediment is transferred to the sediment transport ship. At this time, the elevating wires 12 and 13 are wound together with the opening / closing wire 7 so that the grab bucket 1 does not rotate, but the load is mainly handled by the opening / closing wire 7.

  As described above, according to the scissors device of the present embodiment, the blade edges 3a, 4a of the bucket shells 3, 4 can be moved horizontally by a mechanical mechanism in the steps of FIGS. 6 (a) to (e). Horizontal drilling is possible.

  Next, a configuration in the case where horizontal excavation is performed on the slope of the bottom of the water with the dredger of FIGS. 3 to 6 will be described with reference to FIGS. FIG. 7 is a perspective view showing the opened grab bucket of FIGS. 3 to 6 in an obliquely suspended state. FIG. 8 is a side view showing the grab bucket (closed state) of FIG.

  The grab bucket 1 shown in FIGS. 7 and 8 has a suspension length adjusting chain 21 between the lifting chains 15 and 16 on one side and the suspension member 11 for suspending the bucket shells 3 and 4 of FIG. ing. That is, a connecting portion 22 made of a hook or the like is provided at the joint between the elevating chains 15 and 16, and the suspension length adjusting chain 21 is connected to the elevating chains 15 and 16.

  As shown in FIG. 7, the bucket shells 3, 4 can be moved in the horizontal direction by adding suspension length adjusting means (part B) using the suspension length adjusting chain 21 to the lifting chains 15, 16 (part A) on one side. Suspend diagonally so that it tilts. In this case, by determining the length of the suspension length adjusting chain 21 based on the inclination angle θ (FIG. 8) of the saddle target slope, the entire blade edges 3a and 4a of the bucket shells 3 and 4 are sloped. Can be arranged substantially in parallel. In this way, the grab bucket 1 can be arranged obliquely according to the slope of the dredging target.

  3 and 7, the surface formed by passing through the horizontally extending axis n (FIGS. 3, 4 and 8) of the suspension member 11 and extending in the vertical direction is the support shaft 2 of the bucket shells 3 and 4. The suspension member 11 and the bucket shells 3 and 4 are disposed so as to pass through the center line p. In FIG. 3, the grab bucket 1 is horizontally arranged so that the horizontally extending suspension member 11 and the center line p of the support shaft 2 of the bucket shells 3 and 4 are parallel to each other, but in FIG. The grab bucket 1 is disposed obliquely so that the center line p of the support shaft 2 is inclined with respect to 11.

  As shown in FIG. 7, by hanging the grab bucket 1 diagonally according to the slope to be dredged, excavation can be performed on the slope in the same manner as in FIGS. 6 (a) to 6 (e), and the efficiency matched to the slope. Drilling and dredging becomes possible.

  When FIGS. 6A to 6E are slope excavations, the bottom G is inclined in the direction perpendicular to the drawing sheet, and the direction perpendicular to the sheet is the normal direction. Further, when the grab bucket 1 is suspended, the grab bucket 1 is positioned so that the length direction (direction of the axis n) of the suspension member 11 coincides with the normal direction of the slope.

  7 and 8, the chain length of the delta portion (A portion in FIG. 7) of the lifting chains 15 and 16 is not changed, and the suspension length adjusting chain 21 (B portion in FIG. 7) is used. Although the grab bucket 1 is inclined by this, if the length of a delta part (A part) is changed, excavation like FIG. 6 (a)-(e) will become impossible.

  As described above, according to the dredge apparatus of the present embodiment, the grab bucket 1 is lowered to the design height of the slope with the lifting wires 12 and 13 in exactly the same manner as when the grab bucket 1 is horizontally suspended to the bottom of the water. By simply winding up the opening / closing wire 7 after installation, a smooth saddle face that matches the slope can be formed. In addition, since smooth slope excavation is possible, it is possible to reduce the slope overexcavation, and it is possible to easily form a flat cross section that is close to the design cross section and has a small amount of overexcavation.

  That is, as shown in FIG. 11, the slope that tends to be stepped can be smoothed when performing dredging on the slope, and the surplus digging during slope digging can be reduced. Dredge is possible.

  Moreover, the rotation of the grab bucket 1 can be reduced before the grab bucket 1 is installed by using the suspension member 11 extending horizontally for hanging the grab bucket 1. While excavation of the bottom of the water is allowed to some extent, in the case of slope excavation, if the grab bucket 1 is rotated, the shape of the slope of the slope is reduced three-dimensionally. Therefore, it is possible to prevent the shape of the collar surface from being lowered. In addition, by using the suspension member 11, the inclination adjustment according to the slope inclination angle by the suspension length adjustment chain 21 becomes easy.

  In addition, it is possible to perform smooth dredging and smooth dredging according to the slope by a mechanical structure by simply winding up the opening / closing wire 7 without requiring special grab bucket height control.

  In addition, the conventional horizontal excavation using a normal grab bucket as shown in FIG. 10 enables horizontal excavation by closing the grab bucket and simultaneously controlling the height of the entire grab. Thus, it is technically impossible to excavate the slope as in this embodiment.

  As described above, the modes for carrying out the present invention have been described. However, the present invention is not limited to these, and various modifications can be made within the scope of the technical idea of the present invention. For example, the opening / closing mechanism of bucket shells 3 and 4 in FIG. 5 is an example, and may be another mechanism.

  Further, the elevating chains 15 and 16 and the suspension length adjusting chain 21 may be rope members such as wires and ropes. The suspension member 11 may be a rod-shaped member other than a shape steel, or a steel pipe or a round bar.

  According to the dredging apparatus and dredging method of the present invention, the grab bucket is configured to hang obliquely in accordance with the slope of the dredging object, thereby eliminating the step dug in the slope dredging and reducing the overdraft. Therefore, it is possible to easily form a smooth cross-section with a small surplus amount close to the design cross-section. For this reason, a thin layer dredging is possible on the slope, and the contaminated portion deposited on the upper part of the bottom of the water can be excavated efficiently, and an environmentally-friendly dredging method that does not cause sediment overflow and does not diffuse polluted water can be realized.

1: Grab bucket 2: Support shaft 3, 4: Bucket shell 3a, 4a: Cutting edge 7: Opening / closing wire 10: Anchor device 11: Hanging member 12, 13: Lifting wire (lifting rope member)
15, 16: Elevating chain (suspending rope member)
21: Suspension length adjustment chain (suspending length adjustment rope member)
G: Bottom of water θ: Angle of inclination

Claims (6)

A dredge apparatus comprising: a grab bucket capable of horizontal excavation; elevating means for elevating and lowering the grab bucket; and opening and closing means for opening and closing the grab bucket;
The grab bucket includes a pair of bucket shells joined so as to be rotatable about a support shaft, and suspension means for hanging the bucket shell, and the bucket shell is moved up and down by the lifting means. Is raised and lowered, the bucket shell is opened and closed by an up and down operation by the opening and closing means
The suspension means includes a suspension member supported so as to extend in a horizontal direction by a lifting rope member of the lifting means, a pair of suspension rope members disposed between the suspension member and the bucket shell, A suspension length adjusting means capable of adjusting the suspension length of the suspension rope member based on the inclination angle of the target slope,
The suspension means adjusts the suspension length of one of the suspension rope members by the suspension length adjustment means, so that the pair of bucket shells are inclined so that the center line of the support shaft is inclined from the horizontal direction. A dredge device that can be suspended at an angle.   The anchor device according to claim 1, wherein the suspension length adjusting means includes a suspension length adjusting rope member disposed between any one of the suspension rope members and the suspension member.   One of the pair of suspension rope members is connected in the vicinity of both corners of one end of the pair of bucket shells with the support shaft interposed therebetween, and the other is connected to the pair of bucket shells with the support shaft interposed therebetween. The dredging device according to claim 2, wherein two hooks are connected in the vicinity of both corners of the other end, and are connected to the hanging member and the hanging length adjusting rope member at one place.   The pair of bucket shells are configured to move horizontally with the trajectory of the blade edge of each bucket shell substantially in the height position when the pair of bucket shells is rotated about the support shaft by the up and down operation by the opening and closing means and opened and closed. The dredge apparatus according to any one of claims 1 to 3. It is a dredging method that uses a grab bucket that has a pair of bucket shells joined so as to be rotatable about a support shaft and that can be horizontally excavated, and that slopes the slope at the bottom of the water,
The dredging method is characterized in that the dredging of the slope is performed in a state where the bucket shell is obliquely adjusted based on the inclination angle of the slope so that the center line of the support shaft is inclined from the horizontal direction.   The pair of bucket shells are configured to rotate around the support shaft and open and close, and the locus of the blade edge of each bucket shell moves horizontally while maintaining a substantially constant height position when the opening and closing are performed. The dredging method according to claim 5.

Images