JP2001159110A - Road surface washing method for water permeable pavement, and washing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve road surface washing effects for water-permeable pavement with a small amount of washing solution. SOLUTION: A partitioned washing space 12, opened to a road surface side and counterposed via a gap on the road surface 4 of a water-permeable pavement 1 is formed, a jetting hole 14 is located at the top of the washing space, a washing solution 14 is jetted towards the road surface from the jetting hole and a liquid flow jet 18 is formed, a cavitation jet is generated from the washing liquid and a liquid flow jet filled in the washing space, and the effect of road surface washing of the water permeable pavement can be improved with the least washing solution, by effectively washing and removing the substance clogged in a gap portion on the road surface due to the shock wave of the cavitation jet.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method, a cleaning head and a cleaning apparatus for cleaning a road surface of a water-permeable pavement. The improvement of technology to recover

[0002]

2. Description of the Related Art On a general pavement road, if a thin water film is formed on the surface during rainfall, the wheels easily slip easily. This is a phenomenon called a hydroplane phenomenon, which is an important safety issue on a highway. Conventionally, in order to suppress the occurrence of such a hydroplane phenomenon, a pavement referred to as a water-permeable or drainage material having an increased porosity is provided on a surface layer having a thickness of about 10 to 30 mm on a road surface.
(Hereinafter referred to as permeable pavement). That is, as shown in FIG. 10, the surface layer portion of the permeable pavement 1 has a structure in which a void 3 is formed around the aggregate 2, and rainwater or the like that accumulates on the road surface 4 is removed from the gravel (rubble) through the void 3. By infiltrating the water-permeable lower layer and draining the water, a water film is not formed on the road surface of the water-permeable pavement.

[0003] Further, on a conventional smooth pavement surface, an air layer is compressed between the wheels and the road surface, and the plosive sound generated when the compressed air layer collapses and bursts is a major cause of road noise. I have. In this regard, according to the permeable pavement, it is also known that the air compressed by the wheels diffuses into the gaps in the surface layer, thereby suppressing the generation of noise.

However, as shown in FIG. 10, when the automobile tire 5 rotates as indicated by an arrow 7 under a compressive load 6, tire wear powder and road surface material wear powder 8 are generated. When such particles such as the abrasion powder 8 and the earth and sand are clogged in the voids 3 on the surface of the water-permeable pavement, the water permeability is gradually deteriorated, and a water film is easily generated and noise is generated. growing.

Therefore, conventionally, a high-speed water jet or the like is sprayed on a water-permeable road surface to break and release a layer of a clogging substance such as powder clogged in a gap of the road surface due to the impact of the water flow. A technique of washing away powder and the like by a water flow has been proposed (Japanese Patent Application Laid-Open No. 3-137310, Japanese Patent Application Laid-Open No. 10-33
No. 7545, Patent No. 2914895).

In addition, a cleaning liquid is brought into contact with and held on a water-permeable road surface, and ultrasonic vibration is applied to the cleaning liquid to release clogging substances such as powder clogged in gaps on the road surface. A technique has been proposed for sucking and recovering the same together with a washing liquid (Japanese Patent Application Laid-Open No. H8-100418).

[0007]

However, the method of spraying a water jet from a water injection nozzle toward a water-permeable road surface to wash out clogging substances clogged in a gap is because the impact pressure of the water jet of the water jet is small. In addition, it is not easy to efficiently remove the powder that is tightly packed in the gaps on the pavement surface because the impact action is difficult to penetrate in the depth direction of the pavement and the impact area is small.

Therefore, according to the conventional water jet method, the moving speed of the water injection nozzle, that is, the cleaning speed must be reduced, so that the cleaning time becomes longer, and there is a problem that regulation such as blocking traffic is required. is there. Such problems can be solved to some extent by increasing the injection pressure,
The effect of impact cleaning by a water jet is also limited, and there is a problem that an excessively high injection pressure increases energy cost. Further, since the water jet has a large noise, a problem of noise occurs when the injection pressure is increased in a suburb of an urban area. In addition, since the amount of water used increases and the amount of drainage increases accordingly, there is a problem that a large-sized vacuum device and a special drain tank are required.

On the other hand, according to the conventional cleaning method using ultrasonic waves, it is not always practical because sufficient ultrasonic energy is required for sufficiently efficient cleaning.

It is an object of the present invention to improve the effect of cleaning a road surface of a permeable pavement with a small amount of cleaning liquid.

[0011]

The above objects can be attained by the following means. Basically, a partitioned cleaning space is formed facing the road surface of the permeable pavement with a gap open to the road surface side, and the cleaning liquid is sprayed toward the road surface in the cleaning space. Thus, a liquid jet with cavitation is formed, and the road surface is washed with the liquid jet.

That is, when the cleaning liquid (water or the like) is injected into the cleaning space as described above, the amount of the cleaning liquid leaking from the gap between the cleaning surface and the road surface is small, so that the cleaning space is filled with the cleaning liquid. When the cleaning liquid is jetted into the cleaning space filled with the cleaning liquid to form a liquid jet (water jet), cavitation is severely generated. Here, cavitation means that when the hydrodynamic pressure of a liquid becomes lower than the vapor pressure, the liquid is emulsified by splitting into a two-phase system consisting of a liquid phase and a gaseous phase. Refers to the phenomenon that causes When such a cavitation jet (Cavitating Jet) collides with the clogged permeable pavement road surface, a large number of cavitation bubbles collapse, and the impact pressure generated at that time,
Breaks and releases clogging substances clogging the voids of the permeable pavement. Moreover, the shock wave penetrates deep inside the permeable pavement and effectively releases the clogging material. In other words, when the liquid jet is ejected while the washing space is in a liquid environment, a cavitation jet having an impact pressure larger than the impact pressure (water pressure) of the simple liquid jet is formed. In other words, since the cavitation jet generates a large impact pressure when the cavitation bubbles collapse, it is possible to effectively break the clogging substance and release it from the void without increasing the jet pressure of the liquid jet. Can be. As a result, the cleaning speed can be increased, and the function of the permeable pavement can be restored with a small amount of the cleaning liquid, whereby the amount of drainage can be reduced.

[0013] Further, a partition is separated from the cleaning space,
By forming a partitioned suction space that is open to the road surface side facing the road surface with a gap therebetween, and suctioning the cleaning liquid after washing from the suction space, cavitation
Sludge-like wastewater containing clogging substances such as tire powder and earth and sand released by the jet can be discharged out of the system as washing wastewater. In particular, since the space for suction for suctioning the washing wastewater and the space for washing are separated by a partition wall,
A stable cavitation jet can be formed in the washing space without being affected by the suction of the washing wastewater.

In the above case, the distance (stand-off distance) from the injection hole to the road surface is set in accordance with the second peak of the impact pressure distribution generated in the axial direction of the liquid jet (cavitation jet). Is preferred. As a result, the jet in which powerful vortex cavitation has developed collides with the surface of the permeable pavement, and the function of the permeable pavement can be restored with a smaller amount of the cleaning liquid.

On the other hand, a cleaning head used in a road surface cleaning device for permeable pavement has a cavity formed with an opening facing the road surface of permeable pavement, and an upper inner wall of the cavity facing the road surface. It can be formed having an opened injection hole and an inlet for the high-pressure cleaning liquid communicated with the injection hole. By supplying the high-pressure cleaning liquid to the inlet, a jet of the cleaning liquid is ejected from the injection hole, and a cavitation jet is formed in cooperation with the cleaning liquid filled in the cavity.

Further, a suction cavity formed with a partition wall with respect to the cleaning cavity of the cleaning head and having an opening surface facing the road surface, and communicated with the suction cavity. By forming the cleaning head having the outlet for the cleaning liquid after the cleaning, the sludge cleaning liquid containing the released clogging substance can be discharged out of the system. Moreover,
A stable cavitation jet can be formed in the washing space without being affected by the suction of the washing wastewater.

Here, the cleaning liquid leaks from the gap between the opening edge of the cleaning cavity and the road surface. In order to reduce the amount of this leakage, the opening edge of the cleaning cavity is deformable and is provided inside the cleaning cavity. It is preferable to provide a seal portion made of a member that is unlikely to leak the cleaning liquid. The seal member has an effect of making the cleaning head easily slide on the road surface when the cleaning head is moved on the road surface. As a specific sealing member, a brush formed by implanting a flexible linear member at the opening edge is preferable. When this sealing member is provided in a cleaning head having a suction cavity,
By providing the entire circumference of the opening edge excluding the partition wall between the cleaning cavity and the suction cavity, the cleaning sludge liquid in the cleaning cavity is prevented from flowing into the suction cavity, and from the cleaning head. Of the cleaning liquid can be reduced.

In the above-described cleaning head, it is preferable that a flow path communicating the cleaning liquid inlet and the cleaning cavity is provided with a space having a cross section larger than the flow path cross section. According to this, the high-pressure cleaning liquid supplied from the inlet temporarily accumulates in the space, and is then squeezed out by the small-diameter ejection hole, so that cavitation can be effectively generated.

In the above-described cleaning head, a plurality of injection holes can be provided. In this case, it is preferable that the center axes of the plurality of injection holes are formed so as to intersect at the same position on the water-permeable pavement, and that the diameter of the injection holes decreases as the distance from the center of the cleaning cavity increases. Then, an optimal stand-off distance, that is, a distance between the orifice and the road surface of the permeable pavement is set so that the power of the cavitation jet is maximized.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment of a cleaning head capable of realizing the road surface cleaning method of the present invention. FIG. 1 schematically shows a cross section of the cleaning head, and shows a state where the cleaning head is installed on a road surface of a permeable pavement. As shown in the drawing, the cleaning head 10 has a bell-shaped hollow portion 12 having a lower surface opened in a head member 11, and a plurality of (five in the figure) injection holes 14 opened at the top of the hollow portion 12. These injection holes 14 are used for the head member 1.
The high pressure water header 13 is connected to a high pressure water supply nozzle 16. A bell-shaped suction cavity 20 is formed in the head member 11 via a partition wall 19 adjacent to the cavity 12, and the suction cavity 12 is connected to a suction hose 21 via a communication passage. . The opening edges of the cavity 12 and the suction cavity 20 are formed substantially flush with each other, and a seal member 15 is provided over the entire periphery of the opening edge except for the opening edge of the partition wall 19. The seal member 15 has flexibility and is hardly leakable such that a cleaning liquid such as water leaks slightly.
For example, a brush-like material obtained by implanting a thin wire material can be applied.

The cleaning nozzle 10 formed as shown
Cavities 4 and suction cavities 2 on the road surface 4 of the permeable pavement 1
No. 0 is opposed to the opening surface, and is supported with a small gap between the road surface 4 and the seal member 15 therebetween. Then, a high-pressure cleaning water 17 is supplied from a high-pressure water supply source (not shown).
Is supplied from the inlet 16 to the high-pressure water header 13, the jet flow of the washing water is jetted from the injection hole 14 into the bell-shaped cavity 12. As a result, the interior of the cavity 12 is filled with the cleaning water, and subsequently, a jet stream of the cleaning water is jetted. As a result, the cavitation jet 18 containing a large number of air bubbles is violently generated by the action of the cleaning water and the jet liquid flow filled in the cavity 12. The generated cavitation jet 18
Collides with the road surface 4 of the permeable pavement 1 where clogging has occurred, a large number of cavitation bubbles collapse,
The impact pressure generated at that time breaks and releases the clogging substance clogged in the gap 3 of the permeable pavement 1. Then, the shock wave penetrates deep inside the permeable pavement 1 and effectively releases the clogging substance.

As described above, according to the cleaning head 10 of FIG. 1, since the clogging material is destroyed and released by the cavitation jet 18, the jet pressure of the liquid jet is not increased so much. Clogging material can be easily removed. A predetermined road surface can be cleaned by scanning the road surface while relatively quickly moving the cleaning nozzle 10 in the direction indicated by the arrow 25 in the figure. In other words, by increasing the cleaning speed, the function of the permeable pavement can be restored with a small amount of the cleaning liquid,
As a result, the amount of drainage can be reduced.

The clogging substance released in this manner is suspended in the washing water, flows into the suction cavity 20 as sludge containing air bubbles and the like, and is discharged through the suction hose 21 as waste water (not shown). Guided to the system. In addition,
A part of the cleaning liquid and a part of the cleaning drainage leak as indicated by an arrow 23 through the seal member 15.

In the cleaning nozzle 10 shown in FIG. 1, among the plurality of injection holes 14, the opening diameter at the center, that is, the injection hole provided at the innermost portion of the hollow portion 12 is formed to be the largest. It is formed so that the opening diameter of the ejection hole 14 becomes smaller as approaching. In addition, high pressure water header 1
3, the ejection pressure of each cavitation jet 18 ejected from each ejection hole 14 is the same.

FIG. 2 schematically shows one embodiment of a road cleaning apparatus formed by using the cleaning nozzle 10 of FIG. As shown, the cleaning head 10 is attached to the rear of the dedicated vehicle 31 via a support 32 so as to be towed. A water tank 33 and a plunger pump 34 connected to the water tank 33 are mounted on the cargo bed of the dedicated vehicle 31, and the washing water 35 stored in the water tank 33 is pressurized to a high pressure by the plunger pump 34, and a high-pressure hose The cleaning head 10 is supplied to the cleaning head 10 via a line 36. The pressure of the cleaning water supplied to the cleaning head 10 is increased, for example, to 105 to 900 kgf / cm ² , but can be changed according to the degree of clogging.

On the other hand, the suction hose 21 connected to the suction cavity 20 of the cleaning head 10 is connected to a cyclone-type separator 37.
Is connected to the suction pump 38 via the. As a result, the sludge-like wastewater that has flowed into the suction cavity 20 is passed through the suction hose 21 and is separated by the suction pump 38 into the separator 37.
Where it is separated into a gas and a solid-liquid mixture. The separated gas is discharged from the top as exhaust gas. On the other hand, the sludge-like solid matter 40 is treated as a collected matter. The liquid is sucked out by the suction pump 38 and discharged out of the system as drainage 39.

Here, referring to FIG. 3, the injection hole 14 of the cleaning cavity 12 which is a characteristic part of the cleaning nozzle 10 of the present invention will be described.
Will be described in more detail. FIG. 3 is a diagram illustrating the relationship between the optimum standoff distances Xs1 to Xs3 of the plurality of injection holes 14. As shown in FIG.
The diameter of 4a is d1, and the diameter of the ejection holes 14b on both sides is d1.
2. The diameter of the injection holes 14c on both sides is d3. In this example, the central axes 41a to 41c of the ejection holes 14a to 14c are used.
Are set to intersect at the intersection 43 on the road surface 4 of the permeable pavement. In addition, the distances Xs1 to Xs3 between the outlets of the ejection holes 14a to 14c and the intersection 43 are set to a stand-off distance corresponding to the "second peak" according to the ejection flow rate from each ejection hole. Here, reference numeral 42 in the drawing denotes a clearance dimension between the open end of the cleaning cavity formed in the seal member and the road surface 4. The “second peak”, as shown in FIG. 4, means an area 46 where a second peak of the impact pressure distribution generated in the axial direction of the cavitation jet appears. In this area 46, the scatter is widely dispersed on the collision surface, and the cavitation is the strongest. When the diameter of the ejection hole is reduced, the injection flow rate is reduced, so that the stand-off distance corresponding to the second peak is also reduced. Note that reference numeral 4 in FIG.
5 shows the first peak of the impact pressure distribution. Here, the stand-off distances Xs1 to Xs3 in the example of FIG.

Xs3 <Xs2 <Xs1 By the way, in the example of FIG. 3, five cavitation jets are generated. The most powerful cavitation is generated in the water jet blown out from the ejection hole 14a.

Next, a phenomenon when the cavitation jet generated by the injection hole 14 shown in FIG. 1 or 3 collides with the road surface 4 will be schematically described with reference to FIG. In the figure, the structures of the injection hole 14 and the cavity 12 are omitted, and the cavitation jet 67 is shown as a single jet. Cavitation jet 67 on road surface 4
Impact, cavitational impact pressure is generated in addition to the water jet pressure of the water jet. The impact pressure due to the cavitation is overwhelmingly stronger than the water flow pressure, and the distribution of the impact pressure is as shown by a line 68 in the radial direction of the cavitation jet 67. By the action of the impact pressure, the clogging material clogging the crevice 3 becomes the crevice 3 'from which the clogging material is removed, and the function of water permeability is restored. That is, as compared with the case where cleaning is performed only by the water jet pressure using the conventional water jet, the use of the impact pressure by the cavitation jet according to the present invention makes the impact pressure much stronger and the area to which the impact pressure is applied is much wider.
As a result, the restoration work of the water permeability function by the washing can be efficiently performed.

FIG. 6 shows a comparison of the effect between the conventional technique using a water jet and the purification method according to the present invention using a cavitation jet. In the figure, the vertical axis indicates the relative recovery rate of water permeability. That is, the water permeability recovery rate R of the present invention is expressed as a relative value by dividing the water permeability recovery rate R * according to the prior art. Therefore, the relative recovery rate R / R * of the related art is “1”. On the other hand, the relative recovery rate R / R * according to the present invention is “1.89”.
It can be seen that the recovery rate of the water permeable function was greatly improved.

Similarly, FIG. 7 shows a comparison of the amount of water used (in other words, the amount of drainage) between the conventional technique and the road cleaning method of the present invention. In the figure, the vertical axis indicates the dimensionless water consumption (discharge amount). That is, the used water amount W according to the present invention.
Is divided by the amount of water used W * of the prior art to make it dimensionless. Therefore, the dimensionless water consumption W / W * of the prior art is “1”. On the other hand, the dimensionless water usage W / W * according to the present invention is “0.44”,
The high cleaning ability indicates that the amount of water used can be significantly reduced. However, the slurry-like sludge (sludge-like substance) to be sucked and discharged has a lower water content, so that the suction power is slightly higher than in the prior art.

FIG. 8 shows a comparison of the working time between the prior art and the present invention. In the figure, the vertical axis represents the dimensionless working time with reference to the working time e * of the prior art. Therefore, the dimensionless working time e / e * of the prior art is “1”. On the other hand, the dimensionless working time e / e * of the present invention is "0.66", which indicates that the cleaning time can be greatly reduced. It is important to be able to shorten the working time in this way because it can contribute to the relaxation of traffic regulations on public roads and the assurance of traffic safety.

Although the present invention has been described above with the embodiment of FIG. 1 being most preferable, the shape and structure of the cleaning nozzle according to the present invention are not limited to this. Any cleaning nozzle having a structure in which a liquid jet is ejected to generate cavitation may be used.

For example, a cleaning nozzle 50 having a cross section shown in FIG.
As described above, cleaning by cavitation jet can be realized even if the structure is simplified. That is, as shown in the drawing, the cleaning nozzle 50 forms a hollow portion 52 having a lower surface opened in the head member 51, and forms a high-pressure cleaning water header (or flow path) 53 on the upper portion thereof. The cleaning water header 53 is formed to communicate with the cleaning water header 53 through a plurality of injection holes 54. A sealing member 55 similar to that of FIG. 1 is provided around the opening edge of the hollow portion 52, and the cleaning drainage 58 is discharged from this portion.

With this configuration, the inlet 5
When high-pressure cleaning water 17 is supplied from 6, cleaning water header 5 is supplied.
The washing water is jetted into the cavity 52 from the injection hole 54 as a jet flow through the nozzle hole 3. Then, the jetted cleaning liquid fills the cavity 52, forms a water environment, and generates a cavitation jet in combination with the jet flow.
By the same operation as in the example, the gaps on the road surface are cleaned to remove the clogging substance. In the case of the present embodiment, since the flow path of the cleaning water header 53 is rapidly narrowed at the entrance of the ejection hole 54, a strong contraction occurs. A gas is trapped in the contraction portion, and the gas flows into the cavitation jet 57 intermittently one after another as cavitation nuclei to activate cavitation. As described above, the example of FIG. 9 differs from the example of FIG. 1 in the method of amplifying cavitation, but they are common in that cavitation is actively generated. The optimum stand-off distance Xs corresponding to the second peak is better in this example than in FIG.
Is slightly shorter than in the case of the cleaning nozzle.

Further, in the embodiment shown in FIG. 2, an example is shown in which one cleaning head 10 is towed by a traveling vehicle. However, the present invention is not limited to this. It can also be made to tow. In addition, the cleaning head is provided with only the cleaning cavity without providing the suction head, and is formed in a pair with respect to the traveling direction of the dedicated vehicle for traveling and towing the cleaning cavity. An opening such as a suction hose for sucking waste water discharged from the cleaning cavity of the cleaning head can be arranged.

As described above, according to the embodiment of the present invention, the clogging material on the water-permeable road surface is effectively removed by the impact pressure of the cavitation jet.
The effect is higher than a water jet that simply uses flowing water pressure. As a result, the injection pressure of the cleaning water can be reduced. In particular, since the amount of water used at the time of washing is small, a dedicated water supply vehicle is not required or a small-sized water supply vehicle is sufficient, so that an economic advantage is brought about. Similarly, since the amount of drainage can be reduced, a large-sized vacuum (power propelled vehicle) is not required, or a small-sized type is sufficient, resulting in economic merit. Further, since the cleaning effect is high, the cleaning operation time can be shortened.

[0038]

As described above, according to the present invention, there is an effect that the effect of cleaning the road surface of the permeable pavement can be improved with a small amount of cleaning liquid.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a position embodiment of a cleaning nozzle according to the present invention.

FIG. 2 is an overall configuration diagram of an embodiment of a cleaning apparatus according to the present invention in which the cleaning nozzle of FIG. 1 is attached to a dedicated vehicle.

FIG. 3 is a schematic diagram illustrating details of a cleaning nozzle in FIG. 1;

FIG. 4 is a diagram illustrating an optimal stand-off distance.

FIG. 5 is an explanatory diagram illustrating the operation of the cavitation jet according to the present invention.

FIG. 6 is a diagram showing a comparison between the present invention and the prior art with respect to the recovery rate of water permeability.

FIG. 7 is a diagram showing a comparison between the present invention and the prior art with respect to the amount of water used.

FIG. 8 is a diagram showing a comparison between the present invention and a conventional technique with respect to a cleaning operation time.

FIG. 9 is a sectional view showing another embodiment of the cleaning nozzle according to the present invention.

FIG. 10 is a diagram illustrating a configuration of a permeable pavement and clogging of a void portion thereof.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Permeable pavement 2 Aggregate 3 Void 4 Road surface 10 Cleaning nozzle 11 Head member 12 Cavity 13 High-pressure water header 14 Injection hole 15 Seal member 16 Inlet 18 Cavitation jet 19 Partition wall 20 Suction cavity 21 Suction hose 21

Claims (14)

[Claims] Claims: 1. A partitioned cleaning space formed on a road surface side of a permeable pavement so as to face the road surface with a gap therebetween, and the cleaning solution is directed toward the road surface in the cleaning space. A method for cleaning a road surface of a water-permeable pavement, comprising forming a liquid jet with cavitation by spraying the liquid jet, and cleaning the road surface with the liquid jet. 2. A partition wall is separated from the cleaning space,
The cleaning device according to claim 1, wherein a separated suction space that is open to the road surface side is formed facing the road surface with a gap therebetween, and the cleaning liquid after washing is sucked from the suction space.
The method for cleaning a road surface of a permeable pavement according to Claim 1. 3. A distance from the injection hole to the road surface,
Second of impact pressure distribution generated in the axial direction of the liquid jet
3. The method for cleaning a road surface of a permeable pavement according to claim 1, wherein the method is set in accordance with a second peak. 4. A cavity formed with an opening facing the road surface of the permeable pavement, an injection hole opened toward the road surface in an upper inner wall of the cavity, and a communication with the injection hole. A cleaning head having a high-pressure cleaning solution inlet. 5. A cleaning cavity formed with an opening facing the road surface of the permeable pavement, an injection hole opened toward the road surface in an upper inner wall of the cavity, and the injection hole. A suction cavity formed with an opening for communicating with the high-pressure cleaning liquid, a partition wall with respect to the cleaning cavity, and an opening facing the road surface; and the suction cavity. A cleaning head having a cleaning liquid outlet port after the cleaning that is communicated with the section. 6. The cleaning device according to claim 4, further comprising a seal portion formed at an opening edge of the cleaning cavity portion with a member that is deformable and hardly leaks a cleaning liquid in the cleaning cavity portion. head. 7. A sealing portion formed of a member that is deformable and hardly leaks a cleaning liquid in the cleaning cavity at an opening edge of the cleaning cavity and the suction cavity except for a partition wall. The cleaning head according to claim 5, wherein 8. The flow path connecting the introduction port and the cleaning cavity has a space having a cross section larger than the cross section of the flow path. Cleaning head. 9. A sum of a distance from an opening position of the injection hole to an opening surface of the cleaning cavity and a distance from the opening surface to the road surface is formed by injecting the high-pressure cleaning liquid from the injection hole. The opening position of the injection hole is set so as to be near a second peak position of an impact pressure distribution generated in the axial direction of the liquid jet. The washing nozzle according to 1. 10. The cleaning nozzle according to claim 4, wherein a plurality of the injection holes are provided in the cleaning cavity. 11. The plurality of injection holes are formed such that respective central axes intersect at the same position on the permeable pavement, and the diameter of the injection holes decreases as the distance from the center of the cleaning cavity increases. The cleaning nozzle according to claim 10, wherein: 12. The cleaning nozzle according to any one of claims 4 to 11, wherein the cleaning nozzle is supported on a traveling vehicle such that the opening side of the nozzle is slidable on the road surface of the permeable pavement. And a high-pressure pump for sucking the cleaning liquid from the cleaning liquid tank and supplying a high-pressure cleaning liquid to the cleaning nozzle. 13. The road surface cleaning device according to claim 12, wherein a suction pump for sucking drainage containing clogging substances generated at the cleaning nozzle via a suction hose is mounted on the traveling vehicle. 14. The at least two cleaning heads according to claim 4, which are arranged in a pair with respect to the traveling direction of a dedicated vehicle for traveling and towing, and drainage discharged from the cleaning head is sucked between the two cleaning heads. Road cleaning device in which an opening of a suction means is arranged.