Dredging device for river regulation
Through the combination of rotating plates, crushing knives and shearing knives, the problems of dense silt and aquatic plants obstruction are solved, and efficient river dredging effect is achieved.
Patent Information
- Application Number
- CN202511008614.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-22
- Publication Date
- 2025-09-16
AI Technical Summary
Existing dredging equipment is difficult to effectively break up dense silt and cut off aquatic plants, resulting in poor river dredging results.
It adopts a combination of rotating plates, crushing knives, rotating arms, shearing knives and other mechanisms. The rotating plates separate debris, the crushing knives crush aquatic plants, the rotating arms crush dense silt, and the shearing knives cut off aquatic plants, thereby enhancing the dredging effect.
It significantly improves silt fluidity and dredging efficiency, reduces travel resistance, and enhances river dredging effects.
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Figure CN120649525A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of river dredging, and in particular to a dredging device for river regulation. Background Art
[0002] With the acceleration of urbanization, soil erosion has intensified, resulting in the accumulation of river silt year by year, which has had a serious impact on the ecological safety and flood control function of water bodies. The heavy metals and organic pollutants enriched in the silt are continuously released, causing water quality deterioration and ecosystem degradation, triggering multiple hazards, and significantly weakening flood control capabilities, exacerbating the risk of urban waterlogging. Therefore, it is necessary to dredge the river. Existing dredging equipment usually uses an operating ship equipped with a silt suction pump to suck up the silt in the river to complete the dredging of the river.
[0003] Due to the long-term sedimentation of silt, some of the silt is relatively dense. The current dredging equipment is not convenient for breaking up the dense silt when dredging the river, resulting in poor fluidity of the silt, and criss-crossing aquatic plants will grow in the silt. The current dredging equipment is difficult to break off the aquatic plants that cause obstructions in front when dredging the river, resulting in greater travel resistance, which leads to poor dredging effect on the river. Summary of the Invention
[0004] In order to overcome the above shortcomings, the present invention provides a dredging device for river channel regulation, which can crush dense silt to increase the fluidity of the silt and cut off the aquatic plants that cause obstructions in front to reduce the travel resistance, thereby enhancing the dredging effect on the river channel.
[0005] The technical implementation scheme of the present invention is: a dredging device for river channel regulation, including a mounting frame, a connecting pipe fixedly connected to the mounting frame, a telescopic pipe slidably connected in the connecting pipe, a silt suction bin fixedly connected to the telescopic pipe, a hydraulic rod fixedly connected to the mounting frame, the telescopic rod of the hydraulic rod fixedly connected to the silt suction bin, a separation mechanism provided on the silt suction bin, and a crushing mechanism provided on the silt suction bin.
[0006] In a preferred embodiment of the present invention, the sludge suction bin is a semi-closed structure.
[0007] In a preferred embodiment of the present invention, a protective cover is further included, and the protective cover is fixedly connected to the top of the sludge suction bin.
[0008] In a preferred embodiment of the present invention, the separation mechanism includes an isolation chamber, which is fixedly connected to the lower part of the sludge suction chamber, and the sludge suction chamber is communicated with the isolation chamber. A rotating plate is rotatably connected in the sludge suction chamber, and a link frame is fixedly connected to the rotating shaft at one end of the rotating plate. A sliding groove is provided on the link frame, and a push-pull electromagnet is fixedly connected to the sludge suction chamber, and the telescopic rod of the push-pull electromagnet is slidably connected to the sliding groove of the link frame.
[0009] In a preferred embodiment of the present invention, a mesh plate is provided on the isolation chamber.
[0010] In a preferred embodiment of the present invention, the crushing mechanism includes a support ring, which is fixed in the sludge suction bin, a motor is fixed in the protective cover, a crushing knife is rotatably connected to the support ring, and bevel gears are fixed on the output shaft of the crushing knife and the motor, and the two bevel gears are meshed.
[0011] In a preferred embodiment of the present invention, it also includes a dispersing mechanism, which is provided on the sludge suction bin and is used to disperse the sludge. The dispersing mechanism includes a support frame, the support frame is fixedly connected to the top of the sludge suction bin, the support frame is rotatably connected to the first crankshaft, the sludge suction bin and the support frame are rotatably connected to a first synchronous wheel, a universal joint is fixedly connected between the first synchronous wheel and the first crankshaft, a second synchronous wheel is fixedly connected to the output shaft of the motor, a synchronous belt is wound around the second synchronous wheel and the first synchronous wheel, six rotating arms are rotatably connected to the sludge suction bin, and a synchronous frame is rotatably connected between the six rotating arms, a strip groove is provided in the middle of the synchronous frame, and the strip groove of the synchronous frame is slidably connected to the first crankshaft.
[0012] In a preferred embodiment of the present invention, the rotating arm is arranged obliquely.
[0013] In a preferred embodiment of the present invention, an obstacle removal mechanism is further included, which is arranged on a support frame and is used to disconnect obstacles. The obstacle removal mechanism includes a second crankshaft, which is rotatably connected to the support frame. Two first shearing knives are slidably connected to the sludge suction bin, and the two first shearing knives are each provided with a straight groove on the upper part. The straight grooves of the two first shearing knives are respectively slidably connected to the two ends of the second crankshaft. Two first auxiliary shearing knives are fixedly connected to the sludge suction bin, and the two first auxiliary shearing knives are respectively in contact with the two first shearing knives. A worm is fixedly connected to the first crankshaft, and a worm wheel is fixedly connected to the second crankshaft, and the worm wheel is engaged with the worm.
[0014] In a preferred embodiment of the present invention, a disconnecting assembly is further included, wherein the disconnecting assembly includes a sliding frame, the sliding frame is slidably connected to the support frame, two space cams are fixedly connected to the second crankshaft, the space cams are provided with guide grooves, the guide grooves of the two space cams are slidably connected to the sliding frame, a second shearing knife is fixedly connected to the sliding frame, the second shearing knife is slidably connected to the sludge suction bin, a second auxiliary shearing knife is fixedly connected to the bottom of the sludge suction bin, and the second auxiliary shearing knife is in contact with the second shearing knife.
[0015] Compared with the prior art, the present invention has the following advantages: 1. The output shaft of the motor drives the crushing knife to rotate through two bevel gears, so that the crushing knife crushes the aquatic plants mixed in the silt, thereby preventing the aquatic plants from entangled with each other and blocking the pipeline, thereby enhancing the dredging effect on the river channel; the debris with higher density is not convenient to be sucked out by the silt suction pump, so that the debris accumulates in the silt suction bin, and the rotating plate rotates upward, so that the silt and water flow push the debris into the isolation bin, and then the rotating plate is reset to re-block the connecting port of the silt suction bin, so that the debris accumulated in the silt removal bin is cleaned and collected, thereby making the silt suction bin more unobstructed, and significantly enhancing the dredging effect on the river channel.
[0016] 2. The reciprocating translation of the synchronous frame will drive the six rotating arms to swing back and forth, causing the rotating arms to break up dense silt, thereby increasing the fluidity of the silt and further enhancing the dredging effect on the river channel; at the same time, the obliquely set rotating arms prevent aquatic plants from being entangled on the rotating arms.
[0017] 3. The first shearing knife moves up and down and intersects with the first auxiliary shearing knife. At the same time, the second shearing knife moves back and forth and intersects with the second auxiliary shearing knife, thereby cutting off the water plants that cause obstructions in front, thereby reducing the travel resistance and further enhancing the dredging effect on the river. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention.
[0019] Figure 2 It is a schematic diagram of the cross-sectional three-dimensional structure of the present invention.
[0020] Figure 3 It is a schematic diagram of a partially cutaway three-dimensional structure of the present invention.
[0021] Figure 4 It is a schematic diagram of the three-dimensional structure of the separation mechanism of the present invention.
[0022] Figure 5 It is a partial three-dimensional structural schematic diagram of the separation mechanism of the present invention.
[0023] Figure 6 It is a schematic diagram of the split three-dimensional structure of the separation mechanism of the present invention.
[0024] Figure 7 It is a schematic diagram of the three-dimensional structure of the crushing mechanism of the present invention.
[0025] Figure 8 It is a schematic diagram of the cross-sectional three-dimensional structure of the crushing mechanism of the present invention.
[0026] Figure 9 It is a schematic diagram of the three-dimensional structure of the breaking up mechanism of the present invention.
[0027] Figure 10It is a schematic diagram of the split three-dimensional structure of the breaking up mechanism of the present invention.
[0028] Figure 11 It is a schematic diagram of the three-dimensional structure of the obstacle removal mechanism of the present invention.
[0029] Figure 12 It is a schematic diagram of the disassembled three-dimensional structure of the obstacle removal mechanism of the present invention.
[0030] Figure 13 It is a partial three-dimensional structural schematic diagram of the obstacle removal mechanism and disconnection assembly of the present invention.
[0031] Figure 14 It is a schematic diagram of the three-dimensional structure of the disconnection component of the present invention.
[0032] Figure 15 It is a schematic diagram of the split three-dimensional structure of the disconnection mechanism of the present invention.
[0033] Among them, the above-mentioned drawings include the following figure marks: 1. mounting frame, 2. connecting pipe, 3. telescopic pipe, 4. sludge suction bin, 5. hydraulic rod, 6. protective cover, 7. separation mechanism, 71. isolation bin, 72. rotating plate, 73. link frame, 74. push-pull electromagnet, 8. crushing mechanism, 81. support ring, 82. motor, 83. crushing knife, 84. bevel gear, 9. breaking up mechanism, 91. support frame, 92. first crankshaft, 93. first synchronous wheel, 931. universal joint, 932. synchronous belt, 933. second synchronous wheel, 94. synchronous frame, 95. rotating arm, 10. obstacle removal mechanism, 101. second crankshaft, 102. first shearing knife, 103. first auxiliary shearing knife, 104. worm, 1041. worm gear, 11. disconnecting assembly, 111. sliding frame, 112. space cam, 113. second shearing knife, 114. second auxiliary shearing knife. DETAILED DESCRIPTION
[0034] First of all, it should be noted that in the various embodiments described, identical components are provided with identical reference numerals or identical component names, wherein the disclosure contained throughout the entire description can be transferred to the same components having the same reference numerals or identical component names. Positional designations selected in the description, such as top, bottom, lateral, etc., also refer to the directly described and illustrated figures and are transferred to the new position in the event of a change in position.
[0035] Example 1: A dredging device for river regulation, such as Figures 1-8As shown, it includes a mounting frame 1, which is used to install the device on a work boat. The mounting frame 1 is connected to a connecting pipe 2 by bolts, and a telescopic pipe 3 is slidably connected to the connecting pipe 2. The telescopic pipe 3 is connected to a silt suction bin 4 by bolts. The silt suction bin 4 is used to suck silt from the river channel. The mounting frame 1 is connected to a hydraulic rod 5 by bolts, and the telescopic rod of the hydraulic rod 5 is connected to the silt suction bin 4 by bolts. The silt suction bin 4 is provided with a separation mechanism 7 for separating debris such as stones and glass, and the silt suction bin 4 is provided with a crushing mechanism 8 for crushing aquatic plants.
[0036] The silt suction bin 4 is a semi-enclosed structure, which can reduce the diffusion of silt from the silt suction bin 4 to pollute the river water.
[0037] A protective cover 6 is also included, which is connected to the top of the sludge suction bin 4 by bolts and is used to protect parts.
[0038] The separation mechanism 7 includes an isolation chamber 71, which is connected to the lower part of the sludge suction chamber 4 by bolts. The sludge suction chamber 4 is communicated with the isolation chamber 71. The isolation chamber 71 is used to isolate debris such as stones and glass. A rotating plate 72 is rotatably connected to the sludge suction chamber 4. The rotating plate 72 is used to control the communication between the sludge suction chamber 4 and the isolation chamber 71. A link frame 73 is connected to the rotating shaft at one end of the rotating plate 72 by bolts. A slide groove is provided on the link frame 73. A push-pull electromagnet 74 is connected to the sludge suction chamber 4 by bolts. The telescopic rod of the push-pull electromagnet 74 is slidably connected to the slide groove of the link frame 73.
[0039] A mesh plate is provided on the isolation chamber 71 , and the mesh plate on the isolation chamber 71 is used to discharge the sludge in the isolation chamber 71 .
[0040] The crushing mechanism 8 includes a support ring 81, which is connected to the silt suction bin 4 by bolts. A motor 82 is connected to the protective cover 6 by bolts. A crushing knife 83 is rotatably connected to the support ring 81. The crushing knife 83 is used to crush aquatic plants. The crushing knife 83 and the output shaft of the motor 82 are both connected to a bevel gear 84 through a keyway, and the two bevel gears 84 are meshed.
[0041] Initially, the rotating plate 72 blocks the communication port of the isolation chamber 71, so that the silt suction chamber 4 is not connected to the isolation chamber 71. First, the operator installs the mounting frame 1 on the bow of the workboat and connects the connecting pipe 2 to the silt suction pump. Then, the telescopic rod of the hydraulic rod 5 is controlled to extend to drive the silt suction chamber 4 downward, so that the silt suction chamber 4 is pressed into the silt of the river channel. At the same time, the telescopic pipe 3 is extended from the connecting pipe 2. Then, the operator starts the sewage pump and the motor 82, and controls the workboat to move forward slowly. The semi-enclosed silt suction chamber 4 will confine the silt inside the silt suction chamber 4. At the same time, the silt suction pump sucks the silt of the river channel through the connecting pipe 2, the telescopic pipe 3 and the silt suction chamber 4, thereby dredging the river channel; water plants will grow in some of the silt, and the output shaft of the motor 82 will drive the crushing knife 83 to rotate through the two bevel gears 84, so that the crushing knife 83 crushes the water plants mixed in the silt, thereby preventing the water plants from entangled with each other and blocking the pipes, thereby enhancing the dredging effect on the river channel; because the silt may be mixed with stones, glass and other debris, the stones and glass with higher density are not easy to be sucked out by the silt suction pump, so that the debris accumulates in the silt suction chamber. When the silt suction chamber 4 is opened, the silt suction chamber 4 is opened, and the silt suction chamber 4 is opened, and the silt suction chamber 4 is opened, and the silt suction chamber 4 is opened, the silt suction chamber 4 is opened, and the silt suction chamber 4 is opened. When the silt suction chamber 4 is opened, ... The debris in the silt removal bin is cleaned and collected, making the silt suction bin 4 more unobstructed and significantly enhancing the dredging effect on the river channel; when the rotating plate 72 is opened, part of the silt will enter the isolation bin 71 along with the debris. At this time, the silt in the isolation bin 71 is released through the mesh plate of the isolation bin 71, thereby reducing the burden on the movement of the silt suction bin 4; after dredging is completed, the operator controls the hydraulic rod 5 to retract and drive the silt suction bin 4 and the telescopic tube 3 to reset, and then turns off the silt suction pump and the motor 82, and then cleans the debris in the isolation bin 71.
[0042] Example 2: Based on Example 1, Figures 1-10As shown, it also includes a breaking up mechanism 9, which is provided on the silt suction bin 4 and is used to break up the silt. The breaking up mechanism 9 includes a support frame 91, which is connected to the top of the silt suction bin 4 by bolts, and a first crankshaft 92 is rotatably connected to the support frame 91. A first synchronous wheel 93 is rotatably connected between the silt suction bin 4 and the support frame 91, and a universal joint 931 is connected between the first synchronous wheel 93 and the first crankshaft 92 through a keyway. A second synchronous wheel 933 is connected to the output shaft of the motor 82 through a keyway, and a synchronous belt 932 is wound around the second synchronous wheel 933 and the first synchronous wheel 93. Six rotating arms 95 are rotatably connected to the silt suction bin 4, and the rotating arms 95 are used to break up dense silt. A synchronous frame 94 is rotatably connected between the six rotating arms 95. A strip groove is provided in the middle of the synchronous frame 94, and the strip groove of the synchronous frame 94 is slidably connected to the first crankshaft 92. The first crankshaft 92 drives the rotating arm 95 to swing back and forth through the synchronous frame 94.
[0043] The rotating arm 95 is arranged obliquely, and the obliquely arranged rotating arm 95 can reduce the entanglement of aquatic plants.
[0044] When the motor 82 rotates, it will drive the second synchronous wheel 933 to rotate. The rotation of the second synchronous wheel 933 will drive the first synchronous wheel 93 to rotate through the synchronous belt 932. The first synchronous wheel 93 will drive the first crankshaft 92 to rotate through the universal joint 931, so that the first crankshaft 92 drives the synchronous frame 94 to move back and forth through the strip groove of the synchronous frame 94. The reciprocating movement of the synchronous frame 94 will drive the six rotating arms 95 to swing back and forth, so that the rotating arms 95 break up the dense silt, thereby increasing the fluidity of the silt and further enhancing the dredging effect on the river channel; at the same time, the obliquely arranged rotating arms 95 make it difficult for aquatic plants to be entangled on the rotating arms 95.
[0045] Example 3: Based on Example 2, Figures 1-15As shown, it also includes an obstacle removal mechanism 10, which is provided on the support frame 91 and is used to disconnect obstacles. The obstacle removal mechanism 10 includes a second crankshaft 101, which is rotatably connected to the support frame 91. Two first shearing knives 102 are slidably connected to the silt suction bin 4. The upper parts of the two first shearing knives 102 are both provided with straight grooves. The straight grooves of the two first shearing knives 102 are respectively slidably connected to the two ends of the second crankshaft 101. The second crankshaft 101 drives the second shearing knife 102 through the straight groove of the shearing knife 102. 2 moves back and forth up and down, two first auxiliary shearing knives 103 are connected to the silt suction bin 4 by bolts, and the two first auxiliary shearing knives 103 are in contact with the two first shearing knives 102 respectively. The first shearing knives 102 and the first auxiliary shearing knives 103 interlace with each other to shear the waterweed. A worm 104 is connected to the first crankshaft 92 through a keyway, and a worm wheel 1041 is connected to the second crankshaft 101 through a keyway. The worm wheel 1041 meshes with the worm 104, and the first crankshaft 92 drives the second crankshaft 101 to rotate through the worm 104 and the worm and worm wheel 1041.
[0046] It also includes a disconnection component 11, which includes a sliding frame 111, which is slidably connected to the support frame 91, and two space cams 112 are connected to the second crankshaft 101 through a keyway, and the space cams 112 are provided with guide grooves, and the guide grooves of the two space cams 112 are slidably connected to the sliding frame 111, and the second crankshaft 101 drives the sliding frame 111 to reciprocate through the space cams 112, and the sliding frame 111 is connected to a second shearing knife 113 by bolts, and the second shearing knife 113 is slidably connected to the silt suction bin 4, and the bottom of the silt suction bin 4 is connected to a second auxiliary shearing knife 114 by bolts, and the second auxiliary shearing knife 114 contacts the second shearing knife 113, and the second shearing knife 113 and the second auxiliary shearing knife 114 are staggered to cut aquatic plants.
[0047] When the first crankshaft 92 rotates, it will drive the second crankshaft 101 to rotate through the worm 104 and the worm wheel 1041, so that the two ends of the second crankshaft 101 drive the two first shearing knives 102 to move back and forth through the straight grooves of the two first shearing knives 102. The up and down reciprocating movement of the first shearing knife 102 will be intertwined with the first auxiliary shearing knife 103. At the same time, the rotation of the second crankshaft 101 will drive the two space cams 112 to rotate, so that the two space cams 112 drive the sliding frame 111 to reciprocate through the guide groove. The reciprocating movement of the sliding frame 111 will drive the second shearing knife 113 to move together. The reciprocating movement of the second shearing knife 113 will be intertwined with the second auxiliary shearing knife 114, thereby cutting off the aquatic plants that cause obstacles in front, thereby reducing the travel resistance and further enhancing the dredging effect on the river channel.
[0048] While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all modifications and equivalent structures and functions.
Claims
1. A dredging device for river regulation, characterized in that: The utility model comprises a mounting frame (1), a connecting pipe (2) is fixedly connected to the mounting frame (1), a telescopic pipe (3) is slidably connected in the connecting pipe (2), a silt suction bin (4) is fixedly connected to the telescopic pipe (3), a hydraulic rod (5) is fixedly connected to the mounting frame (1), the telescopic rod of the hydraulic rod (5) is fixedly connected to the silt suction bin (4), a separating mechanism (7) is provided on the silt suction bin (4), and a crushing mechanism (8) is provided on the silt suction bin (4).
2. A dredging device for river regulation according to claim 1, characterized in that: The sludge suction bin (4) is a semi-enclosed structure.
3. A dredging device for river regulation according to claim 1, characterized in that: It also includes a protective cover (6), which is fixed to the top of the sludge suction bin (4).
4. A dredging device for river regulation according to claim 3, characterized in that: The separation mechanism (7) includes an isolation chamber (71), the isolation chamber (71) is fixedly connected to the lower part of the silt suction chamber (4), the silt suction chamber (4) is communicated with the isolation chamber (71), a rotating plate (72) is rotatably connected in the silt suction chamber (4), a link frame (73) is fixedly connected to a rotating shaft at one end of the rotating plate (72), a sliding groove is provided on the link frame (73), a push-pull electromagnet (74) is fixedly connected to the silt suction chamber (4), and a telescopic rod of the push-pull electromagnet (74) is slidably connected to the sliding groove of the link frame (73).
5. A dredging device for river regulation according to claim 4, characterized in that: The isolation chamber (71) is provided with a mesh plate.
6. A dredging device for river regulation according to claim 4, characterized in that: The crushing mechanism (8) includes a support ring (81), the support ring (81) is fixedly connected to the sludge suction bin (4), a motor (82) is fixedly connected to the protective cover (6), a crushing knife (83) is rotatably connected to the support ring (81), and bevel gears (84) are fixedly connected to the output shafts of the crushing knife (83) and the motor (82), and the two bevel gears (84) are meshed.
7. A dredging device for river regulation according to claim 6, characterized in that: The utility model also includes a dispersing mechanism (9), which is provided on the silt suction bin (4) and is used to disperse the silt. The dispersing mechanism (9) includes a support frame (91), which is fixed to the top of the silt suction bin (4), a first crankshaft (92) is rotatably connected to the support frame (91), a first synchronous wheel (93) is rotatably connected between the silt suction bin (4) and the support frame (91), and a universal joint is fixed between the first synchronous wheel (93) and the first crankshaft (92). The motor (82) is provided with a second synchronous wheel (933) fixedly connected to the output shaft, a synchronous belt (932) is wound around the second synchronous wheel (933) and the first synchronous wheel (93), the silt suction bin (4) is rotatably connected to six rotating arms (95), and a synchronous frame (94) is rotatably connected between the six rotating arms (95), and a strip groove is provided in the middle of the synchronous frame (94), and the strip groove of the synchronous frame (94) is slidably connected to the first crankshaft (92).
8. A dredging device for river regulation according to claim 7, characterized in that: The rotating arm (95) is arranged obliquely.
9. A dredging device for river regulation according to claim 7, characterized in that: The invention also includes an obstacle removal mechanism (10), which is arranged on the support frame (91) and is used to disconnect obstacles. The obstacle removal mechanism (10) includes a second crankshaft (101), which is rotatably connected to the support frame (91). Two first shearing knives (102) are slidably connected to the sludge suction bin (4), and the upper parts of the two first shearing knives (102) are both provided with straight grooves. The straight grooves of the two first shearing knives (102) are respectively slidably connected to the two ends of the second crankshaft (101). Two first auxiliary shearing knives (103) are fixedly connected to the sludge suction bin (4), and the two first auxiliary shearing knives (103) are respectively in contact with the two first shearing knives (102). A worm (104) is fixedly connected to the first crankshaft (92), and a worm wheel (1041) is fixedly connected to the second crankshaft (101). The worm wheel (1041) is meshed with the worm (104).
10. A dredging device for river regulation according to claim 9, characterized in that: The invention also includes a disconnection component (11), wherein the disconnection component (11) includes a sliding frame (111), the sliding frame (111) is slidably connected to the support frame (91), two space cams (112) are fixedly connected to the second crankshaft (101), the space cams (112) are provided with guide grooves, the guide grooves of the two space cams (112) are slidably connected to the sliding frame (111), a second shearing knife (113) is fixedly connected to the sliding frame (111), the second shearing knife (113) is slidably connected to the silt suction bin (4), a second auxiliary shearing knife (114) is fixedly connected to the bottom of the silt suction bin (4), and the second auxiliary shearing knife (114) is in contact with the second shearing knife (113).