Bidirectional discharging type dredging ship

Abstract

The utility model provides a two-way unloading type dredger which comprises a dredger body, a first conveying device and a second conveying device, the first conveying device and the second conveying device are both installed on the dredger body and distributed up and down, the first conveying device is led out from one side of the dredger body, and the second conveying device is led out from the other side of the dredger body. The second conveying device is led out from the other side of the ship body; a discharging port is formed in the ship body, and the first conveying device and the second conveying device are both arranged below the discharging port. The transport ship on the first side is loaded through the first conveying device, after the transport ship is full, the transport ship on the second side is loaded through the first conveying device and the second conveying device in a combined mode, the time that cargoes cannot be loaded in the ship berthing process is saved, shutdown is not needed in the loading process, and the loading efficiency is improved. And the working efficiency of the dredging ship is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to a dredging equipment technical field, concretely relates to a two -way unloading formula dredging boat. BACKGROUND

[0002] In the process of ecological restoration in lake or river, the dredging material in river or lake needs to use large -scale dredging boat, and the dredging material in river or lake is dug up and transported to the transport ship through the conveyor belt, and the dredging material is transported through the transport ship to concentrate treatment.

[0003] The existing dredging boat is generally arranged with excavating equipment at the bow, is transported to the middle part of the ship through the pipeline or conveyor belt, and is output to the transport ship parked on the side of the ship through the conveyor belt in the middle part of the ship. When the transport ship is full of materials, because the driver's cabin of the transport ship is high, the conveyor belt on the dredging boat needs to be rotated and folded to drive the transport ship to drive away, otherwise the driver's cabin will hit the conveyor belt of the dredging boat in the process of driving away, thereby causing damage to the conveyor belt. Therefore, each time the transport ship is berthed to the dredging boat, the conveyor belt needs to be opened, and then the dredging boat can start the dredging work, and when the transport ship is full, the dredging boat needs to be stopped and the conveyor belt is folded back. The full transport ship drives away, and the empty transport ship is parked at the loading position of the dredging boat to unfold the conveyor belt and restart the dredging boat. From the full transport ship driving away to the empty transport ship parking stably, a large amount of time is occupied, which greatly affects the efficiency of dredging.

[0004] In summary, a two -way unloading formula dredging boat is urgently needed to solve or at least partially solve the problems in the prior art. UTILITY MODEL CONTENT

[0005] The utility model aims at providing a two -way unloading formula dredging boat, which aims at solving the problem of low efficiency of the existing dredging boat in alternating loading and unloading materials, and the specific technical scheme is as follows:

[0006] A two -way unloading formula dredging boat, comprising a ship body, a first conveying device and a second conveying device, the first conveying device and the second conveying device are installed on the ship body, and the first conveying device and the second conveying device are distributed in an upper and lower manner, the first conveying device is led out from one side of the ship body, and the second conveying device is led out from the other side of the ship body; The ship body is provided with a discharge port, and the first conveying device and the second conveying device are arranged below the discharge port.

[0007] Further, the first conveying device comprises a fixed frame, a movable frame, a conveying belt, a first driving member and a second driving member, the fixed frame is fixedly connected on the ship body; the first end of the movable frame is hingedly connected on the fixed frame, and the second end of the movable frame is outwardly cantilevered arranged; the conveying belt is simultaneously wound on the fixed frame and the movable frame; the first end of the first driving member is hingedly connected on the ship body, and the second end of the first driving member is hingedly connected on the movable frame; the second driving member is installed on the fixed frame and is used for driving the conveying belt to rotate around the fixed frame and the movable frame.

[0008] Further, the first driving member is a hydraulic oil cylinder or an electric telescopic rod.

[0009] Further, the second driving member comprises a driving wheel, a driven wheel and a power source, the driving wheel is rotationally connected on one end of the fixed frame located in the ship body; the driven wheel is rotationally connected on the end of the movable frame away from the fixed frame; the power source is fixedly connected on the fixed frame, and the output end of the power source is coaxially fixedly connected with the driving wheel; the conveying belt is simultaneously wound outside the driving wheel and the driven wheel.

[0010] Further, the first conveying device further comprises a flow guide plate, and the flow guide plate is arranged on the end of the movable frame away from the fixed frame.

[0011] Further, the first conveying device further comprises a third driving member, the flow guide plate is hingedly connected on the movable frame, the first end of the third driving member is hingedly connected on the movable frame, and the second end of the third driving member is hingedly connected on the flow guide plate.

[0012] Further, the side surface of the flow guide plate close to the movable frame is arranged as an arc surface.

[0013] Further, the first conveying device further comprises a belt pressing roller, and the belt pressing roller is arranged at the hinged position of the fixed frame and the movable frame and is rollingly pressed on the conveying belt.

[0014] Further, the first conveying device further comprises a first supporting roller and a second supporting roller, the first supporting roller is rotationally connected on the fixed frame and is supported on the lower surface of the conveying belt above the fixed frame, and the second supporting roller is rotationally connected on the movable frame and is supported on the lower surface of the conveying belt above the movable frame.

[0015] Further, a plurality of first supporting rollers are arranged and are arranged at intervals along the length direction of the fixed frame, and a plurality of second supporting rollers are arranged and are arranged at intervals along the length direction of the movable frame.

[0016] The technical scheme of the present application has the following beneficial effects:

[0017] In the initial state, the first conveying device and the second conveying device are in the folded state, and in the working state, the transport ship is first parked at the side of the first conveying device of the dredging ship, because the first conveying device is in the folded state at this time, the transport ship can be conveniently moved to below the first conveying device, the first conveying device is unfolded, and the dredging ship is started to work, the dredging material is output from the discharge port of the ship body and falls downward onto the first conveying device, the first conveying device works, and the dredging material is conveyed to the transport ship parked at the side of the first conveying device through the first conveying device, at the same time, another transport ship is parked at the side of the second conveying device and the second conveying device is unfolded for conveying preparation, when the transport ship at the side of the first conveying device is full of the dredging material, the first conveying device is reversely conveyed, so that the dredging material on the first conveying device falls onto the second conveying device below, the second conveying device is started to work, and the second conveying device conveys the dredging material to the transport ship parked at the side of the second conveying device, at this time, the first conveying device is folded, the transport ship full of the dredging material is driven away, the next transport ship is parked at the side of the first conveying device, the first conveying device is unfolded after being parked, and the next round of conveying work is prepared, when the transport ship at the side of the second conveying device is full of the dredging material, the first conveying device is converted to forward conveying, the dredging material is conveyed to the empty transport ship parked at the side of the first conveying device, the second conveying device is folded, the transport ship full of the dredging material at the side of the second conveying device is driven away, and another empty transport ship is parked at the side of the second conveying device, the second conveying device is unfolded, and the above process is repeated. Because the transport ship at the side of the second conveying device is ready for loading when the transport ship at the side of the first conveying device is loading, the transport ship at the side of the second conveying device can immediately join the loading process after the transport ship at the side of the first conveying device is full, so that continuous loading can be carried out, the preparation time in the parking process is saved, and the operation efficiency is greatly improved.

[0018] In addition to the purposes, features and advantages described above, the utility model has other purposes, features and advantages. Below, the utility model will be described in detail with reference to the drawings Figures 1-6 The utility model will be described in further detail. ACCURATE DRAWINGS

[0019] The drawings that constitute a part of this application are used to provide further understanding of the utility model, the illustrative embodiment of the utility model and its description are used to explain the utility model, and do not constitute undue limitation on the utility model. In the drawings:

[0020] Figure 1 It is the overall structure schematic diagram of a bidirectional unloading type dredging ship of the utility model;

[0021] Figure 2 It is the internal structure schematic diagram of a bidirectional unloading type dredging ship of the utility model;

[0022] Figure 3 is a schematic diagram of the overall structure of the first conveying device in the bidirectional unloading type dredging ship of the utility model;

[0023] Figure 4 is Figure 3 the enlarged view of A in the middle;

[0024] Figure 5 is a schematic diagram of the internal structure of the first conveying device in the bidirectional unloading type dredging ship of the utility model;

[0025] Figure 6 is a schematic diagram of the overall structure of the first conveying device in the bidirectional unloading type dredging ship of the utility model.

[0026] Wherein, 1, the ship body; 11, the discharge port; 2, the first conveying device; 21, the fixed frame; 22, the movable frame; 23, the conveying belt; 24, the first driving part; 25, the second driving part; 251, the driving wheel; 252, the driven wheel; 253, the power source; 26, the guide plate; 27, the third driving part; 28, the belt pressing roller; 291, the first supporting roller; 292, the second supporting roller; 3, the second conveying device. DETAILED DESCRIPTION

[0027] In order to facilitate the understanding of the utility model, the utility model will be described more fully below, and the preferred embodiments of the utility model are given. However, the utility model can be realized in many different forms, and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the utility model more thorough and comprehensive.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the utility model belongs. The terms used in the specification of the utility model herein are only for the purpose of describing specific embodiments and are not intended to limit the utility model.

[0029] Embodiment:

[0030] Referring to Figures 1-6 , the embodiment provides a bidirectional unloading type dredging ship, which comprises a ship body 1, a first conveying device 2 and a second conveying device 3, the first conveying device 2 and the second conveying device 3 are both installed on the ship body 1, and the first conveying device 2 and the second conveying device 3 are distributed in an up-down mode, the first conveying device 2 is led out from one side of the ship body 1, and the second conveying device 3 is led out from the other side of the ship body 1; the ship body 1 is provided with a discharge port 11, and the first conveying device 2 and the second conveying device 3 are both arranged below the discharge port 11.

[0031] In particular, the first conveying device 2 and the second conveying device 3 can be individually unfolded and folded. The dredging vessel is provided with a cutter suction device at the front end, through which a mixture of dredged material (i.e. silt) and water accumulated at the bottom of a river or lake is sucked up through a pipeline and filtered through a screen cylinder installed on the hull 1, and the filtered dredged material is discharged from the discharge port 11 on the hull 1. The first conveying device 2 is arranged above the second conveying device 3.

[0032] It can be understood that in the initial state, the first conveying device 2 and the second conveying device 3 are both in the folded state. When working, the transport vessel is first parked on the side of the first conveying device 2 of the dredging vessel. Since the first conveying device 2 is in the folded state at this time, the transport vessel can be conveniently moved below the first conveying device 2, the first conveying device 2 is unfolded, and the dredging vessel is started to work. The dredged material is output from the discharge port 11 of the hull 1 and falls onto the first conveying device 2, the first conveying device 2 works, and the dredged material is conveyed to the transport vessel parked on the side of the first conveying device 2 through the first conveying device 2. At the same time, another transport vessel is parked on the side of the second conveying device 3 and the second conveying device 3 is unfolded for conveying preparation. When the transport vessel parked on the side of the first conveying device 2 is full of cargo, the first conveying device 2 is reversed to convey, so that the dredged material on the first conveying device 2 falls onto the second conveying device 3 below, the second conveying device 3 is started to work, and the second conveying device 3 conveys the dredged material to the transport vessel parked on the side of the second conveying device 3. At this time, the first conveying device 2 is folded, the transport vessel full of dredged material is moved away, and the next transport vessel is parked on the side of the first conveying device 2. After parking, the first conveying device 2 is unfolded, and the next round of conveying work is prepared. When the transport vessel parked on the side of the second conveying device 3 is full of dredged material, the first conveying device 2 is switched to forward conveying to convey the dredged material to the empty transport vessel parked on the side of the first conveying device 2, and the second conveying device 3 is folded. The transport vessel full of dredged material parked on the side of the second conveying device 3 is moved away, and another empty transport vessel is parked on the side of the second conveying device 3, and the second conveying device 3 is unfolded. This process is repeated. Because the transport vessel on the side of the second conveying device 3 is ready for loading when the transport vessel on the side of the first conveying device 2 is loading, the transport vessel on the side of the second conveying device 3 can immediately join the loading process when the transport vessel on the side of the first conveying device 2 is full. Therefore, continuous loading can be carried out, the preparation time during parking is saved, and the work efficiency is greatly improved.

[0033] Further, the first conveying device 2 comprises a fixed frame 21, a movable frame 22, a conveying belt 23, a first driving member 24 and a second driving member 25, the fixed frame 21 is fixedly connected to the ship body 1; the first end of the movable frame 22 is hingedly connected to the fixed frame 21, and the second end of the movable frame 22 is outwardly cantilevered; the conveying belt 23 is wound around the fixed frame 21 and the movable frame 22; the first end of the first driving member 24 is hingedly connected to the ship body 1, and the second end of the first driving member 24 is hingedly connected to the movable frame 22; the second driving member 25 is installed on the fixed frame 21 and is used to drive the conveying belt 23 to rotate around the fixed frame 21 and the movable frame 22.

[0034] It can be understood that the movable frame 22 is driven by the first driving member 24 to rotate upward relative to the fixed frame 21, so that the movable frame 22 is erected upward to realize the folding of the first conveying device 2, and the movable frame 22 is driven by the first driving member 24 to rotate downward, so that the first conveying device 2 is unfolded, and the first conveying device 2 is unfolded and folded by driving the movable frame 22 to rotate relative to the fixed frame 21. The conveying belt 23 is wound around the fixed frame 21 and the movable frame 22, and the conveying belt 23 is driven by the second driving member 25 to rotate to convey the materials.

[0035] It should be noted that the second conveying device 3 has basically the same structure as the first conveying device 2, and details are not repeated here.

[0036] It is worth noting that the first conveying device 2 can convey in the folded state and the unfolded state. When the first conveying device 2 is in the unfolded state, the materials discharged from the discharge port 11 of the ship body 1 are conveyed to the transport ship on the side of the first conveying device 2 in the forward direction. When the second conveying device 3 is in the folded state, the materials discharged from the discharge port 11 of the ship body 1 are conveyed to the second conveying device 3 in the reverse direction, and then conveyed to the transport ship on the side of the second conveying device 3 by the second conveying device 3, realizing bidirectional conveying and improving the work efficiency.

[0037] Further, in the embodiment, the first driving member 24 is a hydraulic cylinder, a first end of the hydraulic cylinder is hinged to the outer wall of the ship body 1, a second end of the hydraulic cylinder is hinged to the outer wall of the movable frame 22, and the movable frame 22 is driven to rotate up and down around the fixed frame 21 by the extension and retraction of the hydraulic cylinder to realize the upward folding and downward unfolding. Specifically, two hydraulic cylinders are arranged, and the two hydraulic cylinders are arranged on the two sides of the movable frame 22 respectively, so that the movable frame 22 is uniformly stressed on both sides, the work is more stable, and the structural strength is increased. It is worth noting that the hydraulic cylinders can be arranged above the movable frame 22 or below the movable frame 22. When the hydraulic cylinders are arranged above the movable frame 22, the movable frame 22 is driven to rotate upward and fold when the hydraulic cylinders are retracted, and the movable frame 22 is driven to rotate downward and unfold when the hydraulic cylinders are extended. When the hydraulic cylinders are arranged below the movable frame 22, the movable frame 22 is driven to rotate downward and unfold when the hydraulic cylinders are retracted, and the movable frame 22 is driven to rotate upward and fold when the hydraulic cylinders are extended.

[0038] It should be noted that in other embodiments of the present application, the first driving member 24 can also be an electric telescopic rod, a first end of the electric telescopic rod is hinged to the side wall of the ship body 1, and a second end of the electric telescopic rod is hinged to the outer wall of the movable frame 22. The function is the same as that of the hydraulic cylinder.

[0039] Further, the second driving member 25 includes a driving wheel 251, a driven wheel 252 and a power source 253, the driving wheel 251 is horizontally rotatably connected to one end of the fixed frame 21 inside the ship body 1 through a bearing, the driven wheel 252 is horizontally rotatably connected to one end of the movable frame 22 away from the fixed frame 21 through a bearing, the power source 253 is fixedly connected to the fixed frame 21, and an output end of the power source 253 is coaxially fixedly connected with the driving wheel 251, and the conveying belt 23 is arranged outside the driving wheel 251 and the driven wheel 252.

[0040] It can be known that the conveying belt 23 is arranged on the driving wheel 251 and the driven wheel 252, and the driving wheel is driven to rotate by the power source 253 to drive the conveying belt 23 to move, and the driven wheel 252 plays a tensioning role to make the conveying belt 23 tightly adhere to the outer wall of the driving wheel 251 and the driven wheel 252, so that the driving wheel 251 can provide a large enough friction force to the conveying belt 23 to drive the conveying belt 23 to move when the driving wheel 251 rotates.

[0041] In the embodiment, the power source 253 includes a motor and a speed reducer, the speed reducer is fixedly connected to the fixed frame 21, the motor is fixedly connected to the housing of the speed reducer, an output end of the motor is connected with an input end of the speed reducer, and an output end of the speed reducer is coaxially connected with the driving wheel 251. In other embodiments of the present application, the power source 253 can also be a hydraulic motor, the hydraulic motor is fixedly connected to the fixed frame 21, an output end of the hydraulic motor is coaxially connected with the driving wheel 251, and the driving wheel 251 is driven to rotate by the hydraulic motor.

[0042] Further, the first conveying device 2 further comprises a guide plate 26, which is arranged on the end of the movable frame 22 away from the fixed frame 21.

[0043] It can be understood that, if there is no guide plate 26, the dredging material conveyed from the movable end to the outside will continue to move outward under the action of inertia, and the faster the conveying speed of the conveying belt 23, the faster the dredging material moves outward, so that in the case of high-speed operation of the conveying belt 23, the dredging material can directly jump over the transport ship parked below and directly fall into the river or lake. Through the arrangement of the guide plate 26, the dredging material conveyed from the movable end is guided by the guide plate 26, so that the dredging material can smoothly enter the transport ship for loading.

[0044] Further, the first conveying device 2 further comprises a third driving member 27, the guide plate 26 is hinged to the movable frame 22, the first end of the third driving member 27 is hinged to the movable frame 22, and the second end of the third driving member 27 is hinged to the guide plate 26.

[0045] It can be understood that, by driving the guide plate 26 to swing relative to the movable frame 22 through the third driving member 27, the guide direction of the guide plate 26 is adjusted, and the dredging material is distributed through the guide plate 26, so that the dredging material can be evenly laid in the cargo box of the transport ship, preventing the dredging material from accumulating on one side of the cargo box of the transport ship to cause the transport ship to overturn due to unstable center of gravity. It should be noted that in the present embodiment, the third driving member 27 is a hydraulic oil cylinder, the first end of the hydraulic oil cylinder is hinged to the movable frame 22, and the second end of the hydraulic oil cylinder is hinged to the guide plate 26. In some other embodiments, the third driving member 27 can also be an electric push rod, the first end of the electric push rod is hinged to the movable frame 22, and the second end of the electric push rod is hinged to the guide plate 26.

[0046] Further, the side surface of the guide plate 26 close to the movable frame 22 is arranged as an arc surface.

[0047] It can be understood that, by arranging the arc surface, the dredging material changes the moving direction under the action of the guide plate 26 during the conveying process, and is conveyed downward to the transport ship, and by arranging the arc surface, the dredging material is prevented from splashing by directly impacting the guide plate 26, and secondly, the guide plate 26 is prevented from being damaged by directly impacting the guide plate 26, thereby improving the service life of the guide plate 26.

[0048] Further, the first conveying device 2 further comprises a belt pressing roller 28, which is arranged at the hinge between the fixed frame 21 and the movable frame 22 and rolls on the conveying belt 23. Specifically, in the embodiment, two belt pressing rollers 28 are arranged, which are respectively rotatably connected to the two sides of the fixed frame 21 and respectively press on the conveying belt 23 at the two side positions, so that the conveying belt 23 is attached to the fixed frame 21 and the movable frame 22. It should be noted that in some other embodiments, the belt pressing roller 28 can also be rotatably connected to the movable frame 22.

[0049] It can be known that through the arrangement of the belt pressing roller 28, when the sliding frame is folded relative to the fixed frame 21, the conveying belt 23 can be close to the movable frame 22 and the fixed frame 21, and the first conveying device 2 can still work smoothly in the folded state.

[0050] Further, the first conveying device 2 further comprises a first support roller 291 and a second support roller 292, the first support roller 291 is rotatably connected to the fixed frame 21 and supports the lower surface of the conveying belt 23 arranged above the fixed frame 21, and the second support roller 292 is rotatably connected to the movable frame 22 and supports the lower surface of the conveying belt 23 arranged above the movable frame 22. The first support roller 291 is arranged in multiple, and the multiple first support rollers 291 are arranged at equal intervals along the length direction of the fixed frame 21, and the second support roller 292 is arranged in multiple, and the multiple second support rollers 292 are arranged at equal intervals along the length direction of the movable frame 22.

[0051] It can be known that through the support of the first support roller 291 on the conveying belt 23 on the fixed frame 21 and the support of the second support roller 292 on the conveying belt 23 on the movable frame 22, the conveying belt 23 can be more stably conveyed.

[0052] The above only describes the preferred embodiments of the present application and is not used to limit the present application. For those skilled in the art, the present application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A bi-directional dredge boat, characterized by: The ship body (1), the first conveying device (2) and the second conveying device (3) are arranged on the ship body (1), and the first conveying device (2) and the second conveying device (3) are arranged in an up-down distribution, the first conveying device (2) is arranged on one side of the ship body (1), and the second conveying device (3) is arranged on the other side of the ship body (1); The ship body (1) is provided with a discharge port (11), and the first conveying device (2) and the second conveying device (3) are arranged below the discharge port (11).

2. The bidirectional unloading dredging ship according to claim 1, wherein: The first conveying device (2) comprises a fixed frame (21), a movable frame (22), a conveying belt (23), a first driving member (24) and a second driving member (25), and the fixed frame (21) is fixedly connected to the ship body (1); The first end of the movable frame (22) is hingedly connected to the fixed frame (21), and the second end of the movable frame (22) is outwardly cantilevered; The conveying belt (23) is arranged on the fixed frame (21) and the movable frame (22); The first end of the first driving member (24) is hingedly connected to the ship body (1), and the second end of the first driving member (24) is hingedly connected to the movable frame (22); The second driving member (25) is arranged on the fixed frame (21) and is used for driving the conveying belt (23) to rotate around the fixed frame (21) and the movable frame (22).

3. The bidirectional unloading dredging ship according to claim 2, wherein: The first driving member (24) is a hydraulic oil cylinder or an electric telescopic rod.

4. The bidirectional unloading dredging ship according to claim 2, wherein: The second driving member (25) comprises a driving wheel (251), a driven wheel (252) and a power source (253), the driving wheel (251) is rotatably connected to one end of the fixed frame (21) inside the ship body (1); The driven wheel (252) is rotatably connected to one end of the movable frame (22) away from the fixed frame (21); The power source (253) is fixedly connected to the fixed frame (21), and the output end of the power source (253) is coaxially fixedly connected to the driving wheel (251); The conveying belt (23) is arranged on the outer sides of the driving wheel (251) and the driven wheel (252).

5. The bidirectional unloading dredging ship according to any one of claims 2-4, wherein: The first conveying device (2) further comprises a flow guide plate (26), and the flow guide plate (26) is arranged on one end of the movable frame (22) away from the fixed frame (21).

6. The bidirectional unloading dredging ship according to claim 5, wherein: The first conveying device (2) further comprises a third driving member (27), the deflector (26) is hinged on the movable frame (22), a first end of the third driving member (27) is hinged on the movable frame (22), and a second end of the third driving member (27) is hinged on the deflector (26).

7. The bidirectional unloading dredging ship according to claim 5, characterized in that: The side surface of the deflector (26) near the movable frame (22) is arranged as an arc surface.

8. The bidirectional unloading dredging ship according to any one of claims 2-4, characterized in that: The first conveying device (2) further comprises a belt pressing roller (28), the belt pressing roller (28) is arranged at the hinge between the fixed frame (21) and the movable frame (22), and the belt pressing roller (28) is in rolling contact with the conveying belt (23).

9. The bidirectional unloading dredging ship according to any one of claims 2-4, characterized in that: The first conveying device (2) further comprises a first supporting roller (291) and a second supporting roller (292), the first supporting roller (291) is rotatably connected to the fixed frame (21), and the first supporting roller (291) supports the lower surface of the conveying belt (23) arranged above the fixed frame (21); The second supporting roller (292) is rotatably connected to the movable frame (22), and the second supporting roller (292) supports the lower surface of the conveying belt (23) arranged above the movable frame (22).

10. The bidirectional unloading dredging ship according to claim 9, characterized in that: The first supporting roller (291) is arranged in multiple, and multiple first supporting rollers (291) are arranged at intervals along the length direction of the fixed frame (21); The second supporting roller (292) is arranged in multiple, and multiple second supporting rollers (292) are arranged at intervals along the length direction of the movable frame (22).

Images