JPH0630882Y2 - Blade cover for dry road cutting machine - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a blade cover attached to a dry road cutting machine used for cutting concrete surfaces, asphalt surfaces and the like (hereinafter referred to as road surfaces).

[Conventional technology]

In this type of road cutting machine, the cutting machine body can be rotated in a plane vertical to the road surface, etc., and the cutting depth of the blade is adjusted by adjusting the inclination of the cutting machine body by this rotation. Has become. Further, in order to prevent dust from scattering due to cutting dust of a cutting machine, a blade cover is installed over the blade.

Conventionally, the blade cover is formed in a structure capable of expanding and contracting according to the rotation of the cutting machine body via the bellows portion so as not to hinder the burying movement of only the blade with respect to the road surface at the time of cutting. .

Further, in order to suppress the deterioration of the cutting performance due to the high heat of the blade of the cutting machine, a through hole for radiating heat or taking in outside air is formed.

[Problems to be solved by the device]

By the way, the generation of dust is unavoidable in a dry road cutting machine where the blade is cooled by air cooling, but if the blade is completely covered with a blade cover in order to prevent scattering of dust, the heat storage degree in the cover will increase. However, there is a problem that the cutting ability increases and the cutting ability decreases. Even if the blade is completely covered with the blade cover, there is a problem that dust is scattered from the cutting groove on the rear side of the blade cover.

According to the experiments by the present inventors, the peripheral speed of the diamond tip at the time of cutting is 40 m / s, although it depends on the outer diameter of the blade.
ec ~ 50 m / sec, so at least about 4
It was confirmed that high heat of 00 ° C to 600 ° C was generated.
It was confirmed that in the state where no measures were taken against this high heat, the diamond deteriorated due to heat, resulting in a significant decrease in cutting ability.In addition, the brazing part of the cutting tip was affected by heat, and the cutting tip fell off. I also learned that an accident would occur.

The purpose can be easily reached by removing the blade cover if it is limited to heat suppression, but in this case, the function to prevent dust scattering is completely lost, the work environment is significantly impaired, and the cutting tip is exposed to the outside. Therefore, the work safety will be significantly reduced. Therefore, in the blade cover attached to this type of cutting machine, measures against conflicting problems are required, but in the structure having only the through hole as described above, dust scattering from the cutting groove In addition to that, scattering of dust from the through holes is unavoidable,
The work environment was getting worse.

In addition, since the opening area of the through hole is determined from the balance of controlling the scattering of dust, the amount of heat radiation or the amount of outside air taken in is not sufficient, which results in low blade cooling efficiency and reduced cutting performance. Was.

In order to deal with such a problem, the applicant of the present invention has proposed a blade cover designed to prevent dust scattering and improve air cooling capability in Japanese Patent Application No. 1-93403 / Kaikai No. 3-32608. This includes a cover body that covers the blade, a suction port member that is installed on the rear side of the cover body, and a shielding member that is installed between the cover body and the suction port member. An opening is formed in the cover body,
The accumulation of heat in the cover body is suppressed by the air flow flowing in through the opening and discharged through the suction port member, and the dust is conveyed to the suction port member. Further, the shielding member is formed with a through hole for directly guiding a part of the dust in the cover body into the suction port member, and the scattering speed of the dust is reduced by the shielding member and sucked into the suction port member. At the same time, a part of the dust reaches directly through the through hole, and the dust in the cutting groove is sucked up by the suction port member.

However, although dust scattering can be prevented when cutting a concrete surface, in the case of an asphalt surface,
It was found that the suction efficiency of the dust in the cutting groove by the suction port member was poor, and the dust was ejected and scattered from the rear end of the blade cover. According to the consideration of the present inventors, this is expected to be due to the difference in the particle properties of the dust particles of concrete and asphalt.

That is, in the case of concrete dust, the particle size is 10μ.
In the case of asphalt dust, the bulk specific gravity is about 0.93, while the particle diameter is 100 μm or less, and the bulk specific gravity is about 1.18. Therefore, the asphalt dust has a high scattering speed and a small attenuation of the scattering speed. Therefore, it can be expected that the asphalt dust is not easily sucked by the suction port member because the asphalt dust is blown far into the cutting groove by the centrifugal force by the blade rotation.

Therefore, the present invention provides a blade cover for a dry road cutting machine, which can prevent dust scattering in asphalt cutting as well as concrete and can enhance the air cooling capacity of the blade, thus improving the working environment and cutting work. Is its purpose.

[Means for Solving the Problems]

In order to achieve the above object, the present invention forms a compulsory air flow that causes outside air to flow into the cover by the suction force of the dust collector and reduces the scattering speed of dust in the cover and the cutting groove. It is intended to improve dust processing and blade cooling at the same time, and its features are:
A cover body that is formed with an opening for taking in outside air and is attached to the cutting machine body by covering the blade with the previous term.
A suction port member that is connected to the dust collector and is located on the upper surface of the previous cutting groove on the rear side of the cover body,
A groove entry member that is slidably installed in this suction port member and enters the cutting groove by its own weight to block the scattering of dust,
The structure is provided with a shielding member that is installed between the cover body and the suction port member and has a through hole for directly guiding a part of dust in the cover body into the suction port member. .

[Action]

According to this invention, for example, by the operation of the dust collector installed in the cutter body, the outside air introduced from the opening of the cover body is guided to the suction member through the cutting groove or the through hole of the shielding member and discharged. A stream is formed. The dust generated by the rotation of the blade is blown toward the cutting groove and the shielding member by the rotating force of the blade. The in-groove entrance member enters the cutting groove by its own weight according to the depth of the cutting groove formed by the rotation of the blade. The dust scattered in the cutting groove collides with the in-groove entry member to reduce or stop the scattering speed and is sucked up by the suction member. On the other hand, part of the dust blown toward the shielding member directly reaches the suction port member through the through hole and is discharged, and the rest is reduced or stopped by the collision with the shielding member and then the through hole. Alternatively, the air is conveyed from the cutting groove to the suction port member and discharged.

Further, dust and hot air floating in the cover body are also carried by the air flow and discharged from the suction port member, and the blade is cooled by the inflow of the outside air.

〔Example〕

 1 to 6 show an embodiment of the present invention.

A front wheel 6 and a rear wheel 8 supported by a support bowl 4 are installed on the lower surface of the cutting machine body 2 so as to be able to move on a road surface R or the like. Further, although not shown, a driving member such as a hydraulic cylinder for rotating the support bowl 4 is arranged in the cutting machine main body 2, and the cutting machine main body 2 supports the rear wheel 8 by the operation of the driving member. It is possible to rotate about 10 as a center in a plane vertical to the road surface R.

A rotary shaft 12 driven by an engine or the like is installed below the front part of the cutting machine main body 2. A cutting tip 14 obtained by sintering diamond grains is brazed to the outer peripheral end of the rotary shaft 12. A plurality of blades 16 fixed in place are attached. The cutting depth of the blade 16 with respect to the road surface R or the like is adjusted by adjusting the inclination of the cutting machine body 2 due to its rotation.

Further, the cutting machine body 2 is provided with a dust collector 22 including an air exhauster 18 and a dust collector 20, and a blade cover 24 attached thereto.
Is connected to the dust collector 22 by a duct hose 26.

To the blade cover 24, a cover main body 28 which is mounted on the cutting machine main body 2 by covering the blade 16 is connected to the rear side of the cover main body 28 on the upper surface of the cutting machine G and to the dust collector 22. Suction port member 30, an in-groove entry member 32 slidably installed in the suction port member 30 and entering the cutting groove G by its own weight, and a shielding member installed between the cover body 28 and the suction port member 30. And 34 are provided.

The cover body 28 is provided with an upper cover 36 fixed to the cutter body 2 and a lower cover 38 connected below the upper cover 36. On the rear side of the upper cover 36, an engaging member 40 capable of engaging with a locking piece formed on the side surface of the cutting machine body 2 is fixed. Further, a bracket 44 having a through hole 42 is attached to the upper front portion, and can be fixed to a bracket 48 formed on the front portion of the cutting machine body 2 with an attachment bolt 46. As a result, the upper cover 36 is fixed to the cutting machine body 2 at a fixed position with respect to the blade 16. Further, a female screw portion 52 for the guide bolt 50 is formed at the front end of the upper cover 36, and a pair of brackets 56 having a guide hole 54 is formed at the rear end. A handle 58 is formed on the upper surface.

On the other hand, the lower cover 38 has a vertically elongated guide hole 60 formed at its front end, and a connecting bolt 62 at its rear end.
Insertion holes 64, 64 for inserting the The lower cover 38 is connected to the upper cover 36 at the front with a guide bolt 50 and at the rear with a connecting bolt 62 and a nut 66 via brackets 56, 56.
The bottom surface of the lower cover 38 is formed with a through hole 68 for moving the blade 16. With such a connecting structure, since the upper cover 36 enters the lower cover 38 to be overlapped with each other, or an expanding / contracting operation in which the overlapped state is released, the inclination degree of the blade cover 24 due to the rotation of the cutting machine body 2 at the time of cutting is obtained. The difference is absorbed. In this example, the upper cover 36 is inserted into the lower cover 38, but it may be reversed.

Further, guide recesses 70 and 72 for guiding the rotary shaft 12 of the blade 16 are formed in the inner portions of the upper cover 36 and the lower cover 38, respectively, with a sufficient size. Further, an opening 74 for taking in outside air is provided on the outer side of the cover body 28 facing the side surface of the blade 16.
And the opening 74 is formed in the upper cover 36.
And the cutout recesses 76 and 78 formed on the outer sides of the lower cover 38, respectively. Note that the experiments conducted by the present inventors have shown that the dust assumed to be scattered from the blade cover 24 is only dust that is blown out in a substantially tangential direction by the rotational force of the blade 16, and the opening 74 The position of is determined based on this result, and is set in the vicinity of the rotary shaft 12. Since it is desirable to take in as much outside air as possible to cool the blade 16, the opening degree is determined by the maximum value at which dust is not actually scattered to the outside. Further, the guide recesses 70 and 72 also play a role of taking in outside air, as the opening 74, by the amount of the allowance. A rubber skirt piece 73 is fixed to the side of the bottom surface of the blade cover 24 with a pressing piece 75 and a set screw 77 in order to increase the suction force.

The blade 16 is fitted into the rotary shaft 12 with front and rear flanges 80 and 82 interposed, and is fastened with a nut 84.

The suction port member 30 is formed in a substantially box shape, and the bottom surface 86 thereof is formed so as to extend to the bottom surface of the cover body 28. Therefore, it is integrally connected to the rear side of the cover body 28. The bottom surface 86 is formed with a through hole 88 facing the cutting groove G. Further, a connection port 92 for connecting the duct hose 26 is formed on the upper surface 90.

The groove insertion member 32 includes a disc-shaped insertion member 94 having a width for entering the cutting groove G and having an insertion hole 96 in the center, and a support shaft 98 inserted into the insertion hole, and the suction port member 30.
The support shaft 98 is engaged with the long holes 100, 100 formed on both sides of the cutting groove G so as to be slidable in the depth direction of the cutting groove G. It is desirable that the width of the advancing body 94 be equal to the width of the cutting groove G and that the penetrating body 94 can enter the cutting groove G by its own weight.

The shielding member 34 is provided on the rear end surface of the cover body 28 and the suction port member 3.
It is formed of a flat plate member also as the front end face of 0, and a through hole 102 for directly guiding a part of dust in the cover body 28 into the suction port member 30 is formed in a part thereof.

Next, the cooling process of the blade 16 and the dust discharging process will be described with reference to FIG.

First, when the dust collector 22 operates, the air flowing in from the opening 74 or the like causes the cut groove G or the through hole 92 of the shielding member 32.
A flow of air that is guided to the suction port member 30 and discharged through the above is formed. The dust M generated by the cutting is the blade 16
Is ejected while being guided to the suction port member 30 by the scattering speed due to the rotational force and the conveyance by the air flow. More specifically, the asphalt dust M blown to the cutting groove G collides with the intruder 94 of the in-groove advancing member 32 that enters the cutting groove G by its own weight, as shown by the broken line arrow S, and has a scattering speed. It is decelerated or stopped and sucked by the suction port member 30. Approaching body 94
As a result, the opening area of the through hole 88 of the suction port member 30 can be narrowed, so that the air flow velocity is increased in the front and rear portions thereof. Therefore, among the asphalt dust M, especially those having a small particle size and a low scattering speed, as shown by the broken line arrow T,
It is sucked up before it collides with the approaching body 94. Further, since the dust M passing between the intruder 94 and the bottom surface of the cutting groove G is light and has a low scattering speed, it is sucked up from the rear side of the in-groove member 32 as indicated by a dashed arrow U. For this reason, it is not always necessary to form the in-groove member 32 to a size that closes the entire cutting groove G in the depth direction. Further, the insertion member 94 of the groove insertion member 32 is not limited to the disk shape, and may be, for example, a plow (disc) or a disc brush. Since the groove advancing member 32 is slidable in the depth direction of the cutting groove G, there is no problem even when not cutting. As described above, even in asphalt cutting, good dust treatment can be performed as in concrete cutting.

If the in-groove member 32 is not provided, the asphalt dust M having a larger particle size and bulk specific gravity than the concrete dust has a large scattering speed as indicated by a broken line arrow Z, and therefore some amount of the asphalt dust M. It is not sucked up by 30, and is jetted from the rear part of the blade cover 24.

On the other hand, a part of the dust M directed to the shielding member 34 has a through hole 1
After passing through 02, it directly reaches the suction port member 30 and is discharged as shown by an arrow W. Further, the other dust M toward the shielding member 34 collides with the shielding member 34 to reduce the scattering speed, and then is conveyed by an air flow to pass through the through hole 102 or the cutting groove G as indicated by broken line arrows X and Y. After that, it is guided to the suction port member 30. The through hole 102 of the shielding member 34 is provided in a portion where most of the dust M hits. The opening area is set to be equal to or smaller than the cross-sectional area of the connection port 92 of the suction port member 30.

In addition, the floating dust M whose scattering speed is reduced in the cover body or which does not have a scattering speed from the beginning is also carried by the air flow, guided to the suction port member 30 and discharged. Furthermore, since the hot air in the cover body 28 is conveyed by the air flow, the accumulation of heat in the cover body 28 is avoided, and
The blade 16 is cooled by the inflow of outside air.

Note that if the scattering speed of the dust that is blown by the rotational force of the blade 16 is higher than the suction force of the dust collector 22, the dust collection performance will be reduced or impossible, and in order to avoid this, the shielding member 34 Through hole 102 and through hole 88 of suction port member 30
The average flow velocity at is always set to be higher than the peripheral speed of the tip of the cutting tip 14.

As described above, the work environment is favorably maintained due to the high efficiency of the dust M dust collection process, and the life of the blade 16 is extended by cooling the blade 16.

[Effect of device]

According to this invention, since the dust blown to the blade cutting groove is sucked into the suction port member after the scattering speed is reduced or stopped by the groove entering member, even asphalt dust having a large particle size and bulk specific gravity is sent to the outside. Can be prevented from scattering. In addition, since the dust that scatters into the cover is sucked into the suction port member after the scattering speed is reduced or stopped by the shielding member, it is possible to perform dust collection processing with high efficiency as a whole, and therefore work by dust scattering The deterioration of the environment can be prevented.

In addition, the accumulation of heat in the cover is suppressed by the air flow, and the blade is cooled by the inflow of the outside air from the opening to suppress the thermal deterioration of the blade. Therefore, the workability is improved and the blade length is increased. The life can be extended.

[Brief description of drawings]

FIG. 1 is a schematic side view showing a usage state of a blade cover for a road cutting machine according to the present invention, FIG. 2 is an exploded perspective view of the blade cover shown in FIG. 1, and FIG. 3 is a perspective view of a groove entry member. FIG. 4 is a schematic cross-sectional view showing the suction and discharge process of dust at the time of cutting, FIG. 5 is a cross-sectional view taken along line VV in FIG. 2,
FIG. 6 is a schematic side view showing a usage state of the cutting machine shown in FIG. 2 ... Cutting machine body, 16 ... Blade 22 ... Dust collector, 24 ... Blade cover 28 ... Cover body, 30 ... Suction port member 32 ... Groove entry member, 34 ... Shielding member 74 ... … Opening part, 102… Through hole G… Cutting groove, M… Dust, R… Road surface, etc.

Claims (1)

[Scope of utility model registration request] 1. A dry road cutting machine for rotating a cutting machine body having a blade in a plane perpendicular to a road surface or the like to form a cutting groove having a predetermined depth, and moving the cutting machine body to cut a predetermined distance. A cover body that is attached to the cutting machine body by forming an opening for taking in outside air, and is attached to the cutting machine body on the upper side of the cutting groove on the rear side of the cover body. A suction port member that is connected to the dust collection device and that is slidably installed in the suction port member and that enters the cutting groove by its own weight to block dust scattering; A blade cover for a dry road cutting machine, which is provided between the cover body and the suction port member, and includes a shielding member having a through hole for directly guiding a part of dust in the cover body into the suction port member. .