Cleaning device and cleaning method

Abstract

To provide a cleaning device and a cleaning method which can reduce costs for maintenance and consumable materials and efficiently clean a placing joint surface.SOLUTION: A cleaning device according to one embodiment is the cleaning device 1 for a fragile product B of a placing joint surface S of a cement-based hardened body. The cleaning device 1 comprises: a base body 2 which has a travel mechanism on the lower part; a hollow tube 4 which has an air jet nozzle that jets the air E to the placing joint surface S on the front side of the base body 2; and a support member 5 which supports the hollow tube 4 on the front side of the base body 2. The support member 5 includes an angle change mechanism 10 which supports the hollow tube 4 and can change the orientation of the air E in the plan view to an inclined direction.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present disclosure relates to a cleaning device and a cleaning method for cleaning fragile objects on a joint surface. [Background technology]

[0002] Patent Document 1 describes a green cutting work vehicle used to treat concrete joint surfaces during dam construction work. The green cutting work vehicle is equipped with a cleaning brush that removes debris from the concrete joint surface and a debris collection mechanism. The cleaning brush is composed of four rotating brushes arranged under the body of the work vehicle. The debris collection mechanism is arranged behind the cleaning brush.

[0003] The debris collection mechanism is composed of a collection brush, a conveyor, and a collection tank. The debris removed from the joint surface by the cleaning brush is sent towards the collection brush. The collection brush kicks the debris up onto the conveyor. The debris kicked up onto the conveyor is transported to the collection tank and collected there. Directly behind the driver's seat of the green cutting work vehicle are the power engine that drives the cleaning brush, collection brush, conveyor, etc., and the machine room that houses the hydraulic drive mechanism that drives the cleaning brush by hydraulic pressure passing through hydraulic piping. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 10-85681 Summary of the Invention [Problem to be solved by the invention]

[0005] As with the green cutting work vehicle described above, cleaning of the joint surface before pouring is performed using a cleaning brush and a recovery brush. However, cleaning with a brush is prone to breakdowns due to reasons such as cement-containing compaction debris sticking to the brush, and maintenance costs can be high. In addition, if the area of ​​the joint surface is large, the brush will wear out and costs such as replacing the brush may be incurred. Furthermore, since there may be steps or the like on the joint surface, there may be a problem that cleaning cannot be performed efficiently with a brush.

[0006] The present disclosure aims to provide a cleaning device and a cleaning method that can reduce costs for maintenance and consumables and efficiently clean joint surfaces. [Means for solving the problem]

[0007] The cleaning device according to the present disclosure is a cleaning device for cleaning fragile objects on the joint surface of a cement-based hardened body. The cleaning device includes a base body having a traveling mechanism at a lower portion, a hollow tube having an air ejection nozzle for ejecting air onto the joint surface in front of the base body, and a support member for supporting the hollow tube in front of the base body. The support member supports the hollow tube and has an angle changing mechanism capable of changing the direction of the air in a plan view to an inclined direction.

[0008] In this cleaning device, a hollow tube is provided in front of a base having a traveling mechanism, and an air ejection nozzle attached to the hollow tube ejects air onto the joint surface of the cement-based hardened body. Therefore, the base can eject air onto the joint surface while traveling, so that fragile objects can be efficiently removed from the joint surface by the air, and the joint surface can be efficiently cleaned even if there is a step or the like on the joint surface. Since a brush is not required, the occurrence of breakdowns can be suppressed and the cost of maintenance can be reduced. In addition, even for a wide joint surface, it is possible to eject air onto the joint surface from an air ejection nozzle attached to the front of the traveling base, so that the cost of consumable materials such as brushes can be reduced. Furthermore, since the direction of the air in a plan view is inclined with respect to the direction in which the base travels, the fragile objects can be moved to one side of the base by the ejection of air. Therefore, since the air moves the fragile objects to one side while the base travels, the fragile objects can be efficiently removed from the joint surface and cleaning can be efficiently performed.

[0009] The cleaning method according to the present disclosure is a cleaning method for cleaning fragile objects on a joint surface by a cleaning device including a base having a traveling mechanism at a lower portion, a hollow tube having an air ejection nozzle for ejecting air onto the joint surface of a cement-based hardened body in front of the base, and a support member for supporting the hollow tube in front of the base. The cleaning method includes a step of supporting the hollow tube in a state inclined with respect to the traveling direction of the base in a plan view, ejecting air from the air ejection nozzle onto the joint surface, and removing fragile objects outside the traveling area of ​​the base as the base travels.

[0010] In this cleaning method, a hollow tube attached to the front of the base has an air ejection nozzle, and air is ejected from the air ejection nozzle onto the joint surface of the cement-based hardened body, so that cleaning can be performed efficiently even if there is a step or the like on the joint surface. This cleaning method does not require a brush, so it is possible to suppress breakdowns and reduce maintenance costs. Furthermore, it is possible to reduce costs for consumable materials. In addition, the direction of the air ejected from the air ejection nozzle is set to be inclined with respect to the running direction of the base, and the air removes fragile objects on the joint surface to the outside of the running area of ​​the base. Therefore, the air can be used to push fragile objects to one side while the base is running, so that fragile objects can be efficiently removed and cleaning can be easily performed.

[0011] The cleaning method may further include a step of recovering the fragile matter using a bucket. In this case, the fragile matter removed from the joint surface can be efficiently recovered by the bucket.

[0012] In the process of removing the fragile objects, the air direction in the horizontal direction relative to the traveling direction of the base may be set to be 3° or more and 60° or less. By setting the air direction relative to the traveling direction to be 3° or more, the fragile objects can be more reliably moved to one side of the base by the air. By setting the air direction relative to the traveling direction to be 60° or less, the hollow tube can be prevented from contacting the front part of the base.

[0013] The cleaning device may include a camera that photographs the location where the air is ejected. The step of removing the fragile object may include a step of photographing the location where the air is ejected with the camera. In this case, the location where the air is ejected can be visually confirmed by checking the image taken by the camera. Therefore, it can be visually confirmed whether the fragile object is being removed from the front of the base by the ejection of air. Effect of the Invention

[0014] According to the present disclosure, it is possible to reduce costs for maintenance and consumables, and to efficiently clean the joint surface. [Brief description of the drawings]

[0015] [Figure 1] FIG. 2 is a perspective view showing an example of a cleaning device and a joint surface according to an embodiment. [Diagram 2] 1A is a perspective view showing a cleaning device according to an embodiment, and FIG. [Diagram 3] 1A is a plan view of the cleaning device, which shows a schematic diagram of the angle changing mechanism, and FIG. 1B is a side view of the cleaning device, which shows a schematic diagram of the angle changing mechanism. [Figure 4] 1A is a perspective view showing a schematic diagram of a camera attached to a cleaning device, and FIG. 1B is a perspective view showing an example monitor that displays an image captured by the camera shown in FIG. [Diagram 5] 1A is a plan view of the cleaning device showing a state in which the direction of air from the air injection nozzle is inclined with respect to the traveling direction, and FIG. 1B is a plan view of the cleaning device showing a state in which the direction of air from the air injection nozzle is not inclined with respect to the traveling direction. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, an embodiment of a cleaning device and a cleaning method according to the present disclosure will be described with reference to the drawings. In the description of the drawings, the same or corresponding elements are given the same reference numerals, and duplicated descriptions are omitted as appropriate. In addition, the drawings may be partially simplified or exaggerated for ease of understanding, and the dimensional ratios and the like are not limited to those shown in the drawings.

[0017] 1 shows an exemplary site A to which the cleaning device and cleaning method according to the present embodiment are applied. For example, at the site A, concrete materials for constructing a centrally impermeable rockfill dam, a trapezoidal CSG dam, or an RCD concrete dam are transported and compacted by a construction machine.

[0018] Pouring the concrete material takes 3 to 48 hours. The concrete material is transported and compacted sequentially by each of a plurality of construction machines. The construction machines include, for example, a vibrating roller and a bucket, and the bucket collects the fragile objects cleaned by the cleaning device 1.

[0019] At the site A, for example, dry concrete is poured and then compacted by a vibrating roller. The maximum coarse aggregate size of the dry concrete is 40 mm or more and 200 mm or less, and the unit cement content of the dry concrete is 90 kg / m 3 Above 180kg / m 3 The water-cement ratio of dry concrete is between 40% and 120%, and the slump value of dry concrete is 3cm or less. After being poured, dry concrete hardens to become a cement-based hardened body.

[0020] At the site A, for example, CSG material is poured and the poured CSG material is compacted by a vibrating roller. The maximum coarse aggregate size of the CSG material is 40 mm or more and 90 mm or less, and the unit cement amount of the CSG material is 50 kg / m 3 Above 160kg / m 3 The water-cement ratio of CSG materials is 40% or more and 120% or less. After being poured, the CSG materials harden to become a cement-based hardened body.

[0021] At the site A, green cutting is performed before concrete materials such as the above-mentioned dry concrete or CSG material are poured. That is, green cutting is performed by spraying high-pressure air or water onto a joint surface S (surface) formed by a cement-based hardened body of already poured concrete. The cleaning device 1 according to this embodiment is, for example, a green cutting machine that performs green cutting.

[0022] In this embodiment, the cleaning device 1 performs cleaning to remove fragile objects (latance, rubble) from the joint surface S. As an example, removal of fragile objects is performed within a range of a depth of 1 mm or more and 10 mm or less from the joint surface S. For example, at a site A where a dam is to be constructed, the joint surface S is wide and a considerable number of cleaning devices 1 are required. As an example, three cleaning devices 1 at the site A perform cleaning to remove fragile objects from the joint surface S. The cleaning devices 1 perform cleaning by spraying air onto the joint surface S.

[0023] FIG. 2(a) is a perspective view showing the cleaning device 1 according to this embodiment. As shown in FIG. 1 and FIG. 2(a), the cleaning device 1 includes a base body 2, a hollow tube 4 having an air ejection nozzle 3 that ejects air onto the joint surface S, and a support member 5 that supports the hollow tube 4. The base body 2 is, for example, a vehicle body having a traveling mechanism 2b at its lower part. In this case, an operator can ride on the base body 2, and the operator can perform cleaning while driving the base body 2. As an example, the base body 2 is a truck vehicle (for example, a 2-ton vehicle).

[0024] The hollow tube 4 is supported by a support member 5 in front of the base body 2. The air ejection nozzle 3 is fixed to the hollow tube 4, and ejects air supplied inside the hollow tube 4 onto a joint surface S located below the hollow tube 4. The hollow tube 4 is connected, for example, to a compressor 6 mounted on the loading platform 2c of the base body 2 via a hose 7. The hose 7 extends from above the loading platform 2c through the longitudinal end of the front window 2d of the base body 2 to the hollow tube 4.

[0025] Compressed air from a compressor 6 is supplied to the hollow tube 4 via a hose 7. As an example, the flow rate of the compressed air from the compressor 6 is 11 m 3 / min, and the discharge pressure of the air from the compressor 6 is 0.7 MPa. Air is supplied from the compressor 6 to the air jet nozzle 3 via the hose 7 and hollow tube 4, and is jetted from the air jet nozzle 3 to the joint surface S. The strength of the cement-based hardened body on the joint surface S due to the jetting of air from the air jet nozzle 3 is, for example, 0.2 N / mm 2 Above 3.0N / mm 2In other words, the strength of the cast cementitious hardened body increases with time, but if the strength is less than 0.2 N / mm 2 Above 3.0N / mm 2 It is preferable to clean the joint surface S by spraying air during the following time periods.

[0026] The hollow tube 4 extends in a direction D2 intersecting the running direction D1 of the base body 2. The direction D2 intersects both the running direction D1 and the width direction D3 of the base body 2. FIG. 2(b) is an enlarged view of an exemplary air ejection nozzle 3. As shown in FIG. 2(b), the air ejection nozzle 3 has a tube portion 3b attached to the hollow tube 4 and a flat portion 3c located at the end of the tube portion 3b opposite to the hollow tube 4. As an example, the tube portion 3b has a cylindrical shape. For example, the inner diameter of the tube portion 3b is 10 mm. As an example, the length L of the flat portion 3c is 15 mm, and the thickness of the flat portion 3c is 2 mm.

[0027] The hollow tube 4 has, for example, a plurality of air ejection nozzles 3, which are arranged at a predetermined interval so as to be lined up along the direction D2. The air ejection nozzles 3 are arranged so that the direction in which air is ejected (air direction) is approximately perpendicular to the direction D2 in which the hollow tube 4 extends. As an example, the hollow tube 4 has 11 air ejection nozzles 3, and the 11 air ejection nozzles 3 are connected 11 meters from the compressor 6. 3 Air is supplied at a flow rate of 1 m per minute from each air nozzle 3. 3 / min of air is sprayed onto the joint surface S.

[0028] For example, wheels 8 are attached to the hollow pipe 4 via mounting members 9. The wheels 8 and mounting members 9 are provided on both ends of the hollow pipe 4. The wheels 8 are guide wheels provided to prevent the air jet nozzle 3 from contacting the joint surface S. In other words, since the lower end of the wheels 8 is located higher than the lower end of the air jet nozzle 3, the wheels 8 come into contact with the joint surface S, thereby preventing the air jet nozzle 3 from contacting the joint surface S.

[0029] The support member 5 supports the hollow tube 4 in front of the base body 2. The support member 5 is fixed to a lower portion between a pair of front lights 2g on the front body 2f of the base body 2. As shown in Fig. 2(a), Fig. 3(a) and Fig. 3(b), the support member 5 has an angle changing mechanism 10 that supports the hollow tube 4 in a state in which the direction of air E ejected from the air ejection nozzle 3 is inclined with respect to the traveling direction D1. The angle changing mechanism 10 makes it possible to change the direction of air E from a state in which it is not inclined with respect to the traveling direction D1 to a state in which it is inclined.

[0030] For example, the angle changing mechanism 10 has a horizontal tilting mechanism 11 and a vertical tilting mechanism 12. The horizontal tilting mechanism 11 and the vertical tilting mechanism 12 are provided between the base 2 and the hollow tube 4. As an example, the horizontal tilting mechanism 11 is provided at a position closer to the base 2 than the vertical tilting mechanism 12. By having the horizontal tilting mechanism 11 and the vertical tilting mechanism 12, the angle changing mechanism 10 does not require a hydraulic cylinder or the like, so that the angle changing mechanism 10 can be simplified in configuration and an increase in costs associated with the angle changing mechanism 10 can be suppressed.

[0031] Each of the horizontal tilting mechanism 11 and the vertical tilting mechanism 12 is, for example, configured with a pair of ratchets that can rotate only in one direction. In the horizontal tilting mechanism 11 and the vertical tilting mechanism 12, for example, the rotatable direction of one of the pair of ratchets is opposite to the rotatable direction of the other, so that the mechanism can be fixed in a state where the angle is changed.

[0032] For example, the horizontal tilting mechanism 11 can fix the hollow tube 4 in a state where the orientation of the hollow tube 4 is changed around an axis 11b extending in the vertical direction. The vertical tilting mechanism 12 can fix the hollow tube 4 in a state where the height position of the hollow tube 4 is changed around an axis 12b extending in the width direction D3. Therefore, the direction of the air E with respect to the traveling direction D1 and the height of the air ejection nozzle 3 can be adjusted.

[0033] As shown in Figures 4(a) and 4(b), the cleaning device 1 includes a camera 13 that captures an image of the portion of the joint surface S where the air E is being sprayed, and a monitor 14 on which the image captured by the camera 13 is displayed. For example, the camera 13 is fixed to a position adjacent to the side mirror 2h of the base body 2. The monitor 14 is, for example, placed on the top surface of the dashboard 2j of the base body 2 and directed toward the driver's seat of the base body 2. This allows the worker to view the portion of the joint surface S where the air E is being sprayed by looking at the monitor 14 while driving the base body 2.

[0034] Next, a cleaning method according to this embodiment will be described. First, as shown in FIG. 3(a) and FIG. 3(b), the direction of the hollow tube 4 supported by the support member 5 is changed to set the direction of the air E ejected from the air ejection nozzle 3 attached to the hollow tube 4 (step of setting the direction of the air). At this time, the height and direction of the air ejection nozzle 3 with respect to the joint surface S are set by the vertical tilt mechanism 12, and the angle θ of the air E in the horizontal direction with respect to the running direction D1 is set by the horizontal tilt mechanism 11. For example, the value of the angle θ that is set is 3° or more and 60° or less. However, the value of the angle θ may be 5° or more, or 10° or more, or may be 30° or less, 20° or less, or 15° or less.

[0035] After the direction of the air E jetted from the air jet nozzle 3 is set as described above, as shown in FIG. 5(a), the air E is jetted from the air jet nozzle 3 onto the joint surface S, and the base body 2 is made to travel on the joint surface S, thereby removing the fragile object B on the joint surface S (step of removing the fragile object). At this time, the fragile object B is removed by the air E to the outside of the travel area R of the base body 2. The direction of the air E jetted from the air jet nozzle 3 is set by changing the inclination (direction) of the hollow tube 4 in a plan view. Therefore, the multiple air jet nozzles 3 are arranged in a substantially straight line along the hollow tube 4 in the extending direction D2. Therefore, the fragile object B on the joint surface S can be blown off uniformly to the outside of the travel area R.

[0036] When the base 2 travels while the air E is being sprayed from the air spray nozzle 3 onto the joint surface S, the camera 13 photographs the place where the air E is sprayed (camera photographing process), and the image taken by the camera 13 is confirmed by visually checking the monitor 14. This makes it possible to know whether the fragile object B is being properly removed from the travel area R by the air E.

[0037] Incidentally, if the direction of the air E in a plan view is not inclined with respect to the traveling direction D1, as shown in Fig. 5(b), the fragile objects B are removed by the air E to both the left and right sides of the traveling region R of the base 2. In this case, since the fragile objects B are dispersed to both the left and right sides, collection of the fragile objects B may become complicated.

[0038] In contrast, in this embodiment, as shown in Fig. 5(a), the direction of the air E in plan view is inclined with respect to the traveling direction D1, so that the air E moves the fragile objects B to one side of the traveling area R of the base 2. By repeating the task of moving the fragile objects B to one side of the traveling area R by the traveling of the base 2, it is possible to accumulate the fragile objects B on that one side. Then, the fragile objects B accumulated on one side are collected by a bucket (process of collecting fragile objects). After repeating the above steps, a series of steps in the cleaning method according to this embodiment is completed.

[0039] Next, the effects obtained from the cleaning device 1 and cleaning method according to this embodiment will be described in detail. In the cleaning device 1 and cleaning method according to this embodiment, a hollow tube 4 is provided in front of the base 2 having the traveling mechanism 2b, and an air ejection nozzle 3 attached to the hollow tube 4 ejects air E onto the joint surface S. Therefore, since the base 2 can eject air E onto the joint surface S while traveling, the air E can efficiently remove fragile objects B from the joint surface S, and the joint surface S can be efficiently cleaned even if there are steps or the like on the joint surface S.

[0040] In addition, the conventional brushes for rubbing the joint surface S are no longer necessary, which can suppress the occurrence of breakdowns and reduce maintenance costs. In other words, when brushes are used, compaction debris containing cement may adhere to the brush, and the adhesion of transfer debris to the brush may cause breakdowns. Furthermore, consumable materials such as brushes are consumed when cleaning a particularly wide joint surface S, which can cause problems such as high replacement costs.

[0041] However, in this embodiment, the air E removes the fragile objects B, making it possible to clean the joint surface S without contact, thereby reducing the possibility of breakdown of the cleaning device 1. In addition, in this embodiment, even for a wide joint surface S, the air E can be sprayed onto the joint surface S from the air spray nozzle 3 attached to the front of the traveling base body 2 to remove the fragile objects B, thereby reducing the cost of consumable materials such as the brushes.

[0042] Furthermore, in this embodiment, the fragile objects B are removed by the air E, and since the direction of the air E in a plan view is inclined with respect to the traveling direction D1 in which the base 2 travels, the fragile objects B can be pushed to one side of the base 2 by the ejection of the air E. Therefore, since the air E pushes the fragile objects B to one side while the base 2 travels, the fragile objects B can be efficiently removed from the joint surface S, and cleaning can be efficiently performed.

[0043] The cleaning method according to the present embodiment further includes a step of using a bucket to collect the fragile object B. Therefore, the fragile object B removed from the joint surface S can be efficiently collected by the bucket.

[0044] In this embodiment, in the direction setting step described above, the direction (angle θ) of the air E in the horizontal direction relative to the running direction D1 in which the base 2 runs is set to be 3° or more and 60° or less. By setting the direction of the air E in the horizontal direction relative to the running direction D1 to be 3° or more, the fragile object B can be more reliably moved to one side of the base 2 by the air E. By setting the direction of the air E relative to the running direction D1 to be 60° or less, it is possible to prevent the hollow tube 4 from contacting the front part of the base 2.

[0045] The cleaning device 1 according to this embodiment includes a camera 13 that photographs the location where the air E is ejected. The process of removing the fragile object B includes a process of using the camera 13 to photograph the location where the air E is ejected. Therefore, the location where the air E is ejected can be visually confirmed by checking the image inside the base 2. Therefore, it can be visually confirmed whether the fragile object B is being removed from the front of the base 2 by the ejection of the air E.

[0046] The above describes the embodiments of the cleaning device and cleaning method according to the present disclosure. However, the cleaning device and cleaning method according to the present disclosure are not limited to the above-mentioned embodiments, and can be modified as appropriate within the scope of the gist described in the claims. In other words, the configuration, shape, size, number, material, and arrangement of each part of the cleaning device, as well as the content and order of the steps of the cleaning method, are not limited to the above-mentioned embodiments, and can be modified as appropriate.

[0047] For example, in the above embodiment, a cleaning device 1 including a base 2 having a hollow tube 4 to which an air ejection nozzle 3 is attached is described, and the cleaning device 1 ejects air E onto a joint surface S to remove fragile objects B. However, the cleaning device may also include a base further including a tube to which a water ejection nozzle is attached, and ejects water onto the joint surface to remove fragile objects. In this case as well, the fragile objects are pulled to one side of the travel area of ​​the base by the water, so that the same effect as in the above embodiment can be obtained.

[0048] In the above embodiment, the cleaning device 1 is described as having a support member 5 provided with an angle changing mechanism 10 having a horizontal tilting mechanism 11 and a vertical tilting mechanism 12. However, the configuration of the angle changing mechanism is not limited to a configuration having a horizontal tilting mechanism 11 and a vertical tilting mechanism 12. For example, the angle changing mechanism may be provided with a hydraulic cylinder that changes the orientation of the hollow tube and the air ejection nozzle, in which case it is possible to change the orientation of the hollow tube and the air ejection nozzle while traveling. [Explanation of symbols]

[0049] 1...cleaning device, 2...base, 2b...traveling mechanism, 2c...cargo bed, 2d...front window, 2f...front body, 2g...front light, 2h...side mirror, 2j...dashboard, 3...air ejection nozzle, 3b...tubular portion, 3c...flat portion, 4...hollow tube, 5...support member, 6...compressor, 7...hose, 8...wheel, 9...mounting member, 10...angle change mechanism, 11...horizontal tilting mechanism, 11b...axis, 12...vertical tilting mechanism, 12b...axis, 13...camera, 14...monitor, A...site, B...fragile object, D1...traveling direction, D2...direction, D3...width direction, E...air, R...traveling area, S...joint surface, θ...angle.

Claims

1. A cleaning device for weak objects on the joint surface of a cement-based hardened body, A base body having a traveling mechanism at a lower portion; A hollow tube having an air ejection nozzle for ejecting air onto the joint surface in front of the base body; a support member for supporting the hollow tube in front of the base; Equipped with the support member supports the hollow tube and has an angle changing mechanism that can change the direction of the air in a plan view to an inclined direction, A wheel is attached to the hollow tube to prevent the air ejection nozzle from contacting the joint surface via an attachment member. Cleaning equipment.

2. A cleaning method comprising the steps of: cleaning fragile objects on the joint surface with a cleaning device comprising a base having a traveling mechanism at a lower portion, a hollow tube having an air ejection nozzle for ejecting air onto the joint surface of a cement-based hardened body in front of the base, and a support member for supporting the hollow tube in front of the base; and recovering the fragile objects using a bucket, A step of supporting the hollow tube in a state inclined with respect to the direction in which the base travels in a plan view, blowing air from the air blowing nozzle onto the joint surface, and removing the brittle object outside the running area of ​​the base as the base travels, The cement-based hardened body is a concrete material that hardens after being poured, The transport and compaction of the concrete material is performed by a plurality of construction machines, and the bucket is included in the construction machines. Cleaning method.

3. In the step of removing the fragile object, a direction of the air in a horizontal direction with respect to a direction in which the base body travels is set to be 3° or more and 60° or less. The cleaning method according to claim 2.

4. The hollow tube is provided with a wheel for preventing the air ejection nozzle from contacting the joint surface via an attachment member. The cleaning method according to claim 2 or 3.

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