JP7149305B2 - rotating nozzle - Google Patents

Description

TECHNICAL FIELD The present invention relates to a rotary nozzle used in a soil improvement device for drilling and improving soil.

As this type of rotary nozzle, there is one disclosed in Patent Document 1, for example. The rotary nozzle described in Patent Document 1 is used in a ground improvement device for drilling and improving the ground by injecting a fluid from the injection nozzle into the ground at high pressure, and is rotated by the reaction force of the injection force of the fluid. It is. That is, the rotary nozzle is provided with a rotating portion formed with a fluid passage communicating with the fluid passage so as to be rotatable around the shaft portion of the fixed portion formed with the fluid passage through which the fluid flows. A part of the passage is inclined at a predetermined angle with respect to the fluid passage of the fixed portion and formed toward the outer peripheral side, and an injection nozzle is attached to the tip end of the inclined fluid passage, and the fluid injected from the injection nozzle is injected. The rotating part is made rotatable around the shaft part by the reaction force of the injection force.

JP 2018-123598 A

However, in the above-mentioned conventional rotary nozzle, no method has been found to control the number of revolutions of the rotary part to a state suitable for the purpose of drilling or improving the ground. Furthermore, when drilling or improving the ground, there is a problem that the rotation of the rotating part stops due to foreign matter such as sand and dust entering the gap formed between the fixed part and the rotating part in the soil. .

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a rotary nozzle capable of controlling the rotation of a rotary part in the soil of the ground.

The invention of claim 1 is used in a ground improvement device for drilling and improving the ground by injecting a high pressure fluid from the injection nozzle into the ground, and in a rotary nozzle that rotates due to the reaction force of the fluid injection force, A rotating part formed with a fluid passage communicating with the fluid passage is rotatably provided around the shaft portion of the fixed portion formed with the fluid passage through which the fluid circulates, and is positioned outside the vertical plane of the fixed portion with respect to the fluid passage. A portion of the fluid passage of the rotating portion is formed obliquely toward the outer periphery, a tip end is provided at the tip of the part of the inclined fluid passage, and an injection nozzle is attached to the tip end to perform the injection. The rotating part is made rotatable about the shaft part by the reaction force of the jetting force of the fluid jetted from the nozzle, and the space formed between the fixed part and the rotating part is sealed. Further , an elastic body is provided at the opening of the space, which is expanded and deformed by a fluid supplied from another fluid passage formed in the fixed portion to apply a brake to the rotating portion.

The invention according to claim 2 is the rotary nozzle according to claim 1, wherein a different fluid passage different from the fluid passage of the shaft portion and the other fluid passage is formed in the fixed portion, and the different fluid passage is formed in the fixed portion. It is characterized in that the contamination-preventing fluid supplied from the fixed portion and the rotating portion can be discharged from the gap between the fixed portion and the rotating portion.

The invention according to claim 3 is the rotary nozzle according to claim 1 or 2, wherein a rotation detection sensor for detecting the rotation state of the rotating part is provided on the opposing surface side of the fixed part and the rotating part. characterized by

As described above, according to the invention of claim 1, the elastic body for applying the brake to the rotating part is provided in the opening of the space formed between the fixed part and the rotating part. can control the rotation of the rotator.

According to the second aspect of the invention, a fluid passage separate from the fluid passage of the shaft is formed in the fixed portion, and the fluid supplied from the separate fluid passage is discharged from the gap between the fixed portion and the rotating portion. By making it free to flow, it is possible to prevent foreign matter such as earth, sand, dust, etc. from entering the gap between the fixed part and the rotating part, and to ensure stable rotation of the rotating part.

According to the third aspect of the invention, a rotation detection sensor for detecting the rotation state of the rotating part is provided on the opposing surface side of the fixed part and the rotating part. I can grasp the number.

1 is a cross-sectional view of a rotary nozzle according to one embodiment of the present invention; FIG. It is a front view of the said rotating nozzle. FIG. 2 is a cross-sectional view taken along line III-III in FIG. 1; FIG. 2 is a sectional view taken along line IV-IV in FIG. 1; It is explanatory drawing which shows the rotation principle of the said rotating nozzle. It is sectional drawing which shows the state which applied the brake to the rotation part of the said rotating nozzle. FIG. 4 is a cross-sectional view showing a state in which air is exhausted from a gap between a fixed portion and a rotating portion of the rotary nozzle;

An embodiment of the present invention will be described below with reference to the drawings.

1 is a cross-sectional view of a rotary nozzle according to one embodiment of the present invention, FIG. 2 is a front view of the rotary nozzle, FIG. 3 is a cross-sectional view along line III-III in FIG. 1, and FIG. 4 is line IV-IV in FIG. FIG. 5 is an explanatory diagram showing the principle of rotation of the rotary nozzle, FIG. 6 is a sectional view showing a state in which the rotating part of the rotary nozzle is braked, and FIG. FIG. 4 is a cross-sectional view showing a state in which air is exhausted from a gap between them;

As shown in FIG. 1, the rotary nozzle 1 is a ground improvement device (not shown) that drills and improves the ground by injecting a fluid S such as water or cement slurry at high pressure from an injection nozzle 25 into the ground (not shown). ), and a fixed portion 10 which is a holder formed up to a shaft portion (shaft) 11 in which a main fluid passage 12 through which the fluid S circulates protrudes at the center, and the main fluid passage 12 A secondary fluid passage (fluid passage) 21 communicating therewith is formed, and a rotating portion 20 which is a rotating body that rotates around the shaft portion 11 of the fixed portion 10 by the reaction force of the ejection force of the fluid S is provided.

The fixed part 10 is formed in a large-diameter columnar shape, and a small-diameter columnar stepped shaft part 11 is integrally formed at the center of the front surface 10a. A rotating portion 20 is rotatably supported on the shaft portion 11 via respective ball bearings 23 positioned on the front and rear sides of the shaft portion 11 .

The main fluid passage 12 of the fixed portion 10 is composed of a large-diameter inner peripheral surface portion 12a from the center of a protruding portion 10c protruding from the rear surface 10b of the fixed portion 10, a conical inner surface portion 12b, and from the large-diameter side to the small-diameter side of the shaft portion 11. It has a formed small-diameter inner peripheral surface portion 12c and a communicating passage 12d bent at right angles from the tip of the small-diameter inner peripheral surface portion 12c. The fluid S is supplied from the large-diameter inner peripheral surface portion 12 a of the main fluid passage 12 into the secondary fluid passage 21 of the rotating portion 20 .

As shown in FIG. 1, the rotating part 20 is formed in a cylindrical shape having the same diameter as the outer diameter of the fixed part 10, and has a center hole 22 having a circular cross section through which the shaft part 11 of the fixed part 10 is inserted. is formed.

1 and 2, the secondary fluid passage 21 of the rotating portion 20 includes an annular passage 21a communicating with the main fluid passage 12 of the fixed portion 10, and an annular passage 21a extending from the annular passage 21a toward the front surface 20a. and a pair of branch passages (parts) 21b, 21b formed radially and 180° apart. Incidentally, as shown in FIG. 1, the gap between the central hole 22 of the rotating part 20 and the annular passage 21a of the secondary fluid passage 21 is fitted into each annular concave portion 22a formed in the central hole 22. A seal ring 24 blocks the fluid S from leaking.

That is, as shown in FIGS. 1 and 2, in the rotating portion 20, a pair of branch passages 21b, 21b communicating with the annular passage 21a of the auxiliary fluid passage 21 are provided for the horizontal main fluid passage 12 of the fixed portion 10. They are three-dimensionally inclined at a predetermined angle .theta. A distal end port 21c is provided at the distal end of each inclined branch passage 21b. Injection nozzles 25 are attached to the pair of tip openings 21c, 21c by screws, respectively. , the rotating portion 20 rotates.

More specifically, as shown in FIGS. 1 and 2, the pair of branch passages 21b, 21b of the rotating portion 20 are inclined at a predetermined angle θ with respect to the shaft portion 11 of the fixed portion 10, so that each branch passage 21b When the fluid S is jetted at high pressure from the jet nozzle 25 attached to the tip port 21c, the rotating part 20 rotates about the shaft part 11 of the fixed part 10 due to the jetting force. That is, as shown in FIG. 5, when the ejection force of the fluid S ejected from the ejection nozzle 25 at high pressure is F, the horizontal component of the ejection force F in the plane orthogonal to the shaft portion 11 of the fixed portion 10 is F ×sin θ=F′ works. This horizontal component force F′ becomes a driving force (reaction force), and the rotating portion 20 rotates around the shaft portion 11 of the fixed portion 10 .

Furthermore, as shown in FIGS. 1 and 6, a recess 20c having a circular cross section is formed in the rear surface 20b of the rotating portion 20. As shown in FIG. A space 26 is formed between the recess 20c and the shaft portion 11 of the fixing portion 10 . In the space 26 formed between the shaft portion 11 of the fixed portion 10 and the recessed portion 20c of the rotating portion 20, there is an air line (another fluid passage) 13 dedicated to the brake formed in the fixed portion 10 and air ( Fluid) A is supplied. At the opening 26a of the space 26, a hard rubber (elastic body) 27 is expanded and deformed by the air A supplied from the air line 13 dedicated to the brake through the air hose 14 to apply the brake to the rotating part 20. is provided to block the The hard rubber 27 is formed in an annular shape with a horizontal U-shaped cross section, and is provided so as to be prevented from coming off via an annular support member 28 . As a result, the inner peripheral portion 27 a of the hard rubber 27 is in pressure contact with the outer peripheral surface 11 b of the stepped large diameter portion of the shaft portion 11 of the fixed portion 10 , and the outer peripheral portion 27 b of the hard rubber 27 is in contact with the concave portion of the rotating portion 20 . It is pressed against the inner peripheral surface 20d of 20c.

1 and 7, a second space 29 is formed between the front surface 10a of the fixed portion 10 and the hard rubber 27. As shown in FIGS. In this second space 29, foreign matter enters from an exclusive exhaust air line (separate fluid passage) 15 formed separately from the main fluid passage 12 of the shaft portion 11 and the brake exclusive air line 13 in the fixed portion 10. Preventive air (fluid) A is supplied. The air A supplied from the exhaust air line 15 through the air hose 16 into the second space 29 passes through the gap t formed between the front surface 10a of the fixed portion 10 and the rear surface 20b of the rotating portion 20. It is designed to be exhausted (discharged) to the outside. The air A discharged to the outside blows away the foreign matter B such as earth, sand, dust, etc. that is about to enter the gap t.

Furthermore, as shown in FIG. 1 , the front surface 11 c of the stepped large-diameter portion of the shaft portion 11 of the fixed portion 10 and the bottom surface 20 e of the recessed portion 20 c of the rotating portion 20 opposite to the front surface 11 c are provided on the side of the bottom surface 20 e of the rotating portion 20 . A proximity sensor (rotation detection sensor) 30 is provided to detect the situation.

As shown in FIGS. 1 and 3, the proximity sensor 30 is attached to the bottom surface 20e of the recessed portion 20c of the rotating portion 20, and includes an annular plate-shaped ring 31 having alternately recessed portions 31a and protruding portions 31b, and a circular ring 31. A sensor unit 32 that calculates and detects the number of rotations of the rotating unit 20 from the number of concave portions 31a and convex portions 31b of the annular plate-shaped ring 31, a cable 33 that outputs a detection signal from the sensor unit 32 to the ground, It has The precision of the proximity sensor 30 can be improved by narrowing the distance between the concave portion 31a and the convex portion 31b formed on the annular plate-shaped ring 31 (increasing the number of concave portions).

According to the rotary nozzle 1 of the embodiment described above, when drilling or improving the ground, as shown in FIG. It is provided in the opening 26a of the space 26 formed between the outer peripheral surface 11b of the diameter portion and the inner peripheral surface 20d of the recessed portion 20c of the rotating portion 20, and the hard rubber 27 is driven by the air A supplied from the air line 13 dedicated to the brake. The rotation of the rotating part 20 in the ground can be controlled by expanding and deforming the rotating part 20 to brake the rotating part 20 and by operating the brake pressure from the ground.

Also, when drilling or improving the ground, as shown in FIG. By always exhausting the air A supplied from the air line 15 dedicated to exhaust from the gap t between the front surface 10a of the fixed portion 10 and the rear surface 20b of the rotating portion 20, the front surface 10a of the fixed portion 10 and the It is possible to prevent foreign matter B such as sand and dust from entering the gap t between the rotating part 20 and the rear surface 20b, and to ensure stable rotation of the rotating part 20. - 特許庁

Furthermore, when drilling or improving the ground, as shown in FIG. By providing the proximity sensor 30 for detecting the number of revolutions of the rotor 20, the number of revolutions of the rotating part 20 in the soil of the ground can be grasped.

In addition, according to the rotary nozzle of the above embodiment, a pair of injection nozzles are inclined on the front side of the rotating portion, but a plurality of injection nozzles may also be inclined on the outer peripheral surface side of the rotating portion. In the case of this form, when drilling the ground using the rotating nozzle, high-pressure water is injected from both the inclined injection nozzle on the front side and the inclined injection nozzle on the outer peripheral surface side to drill the hole. When performing ground improvement, a steel ball is put in the tip side of the main fluid passage to close the secondary fluid passage to the inclined injection nozzle on the front side, and the cement slurry is injected at high pressure from the inclined injection nozzle on the outer peripheral surface side. and improve the ground.

Further, according to the above embodiment, a pair of inclined injection nozzles are provided on the front side of the rotating portion, but three or more may be provided, or a plurality of inclined injection nozzles may be provided on the outer peripheral surface side of the rotating portion.

Furthermore, according to the above-described embodiment, the injection nozzle is provided at an angle on the front side of the rotating part, and no injection nozzle is provided on the front surface of the shaft part of the fixed part exposed from the center hole of the rotating part. The main fluid passage may be formed up to the tip of the shaft portion of the portion, and the injection nozzle may be provided without being inclined on the front surface of the shaft portion of the fixed portion exposed from the center hole of the rotating portion.

REFERENCE SIGNS LIST 1 rotary nozzle 10 fixed part 11 shaft part 11c front surface (faces facing each other)
12 main fluid passage (fluid passage)
13 Air line dedicated to brakes (other fluid passages)
15 dedicated exhaust air line (another fluid passage)
20 Rotating part 20e Bottom surface (opposing surface)
21 secondary fluid passage (fluid passage)
21a Annular passage 21b Branch passage (part)
21c tip opening 25 injection nozzle 26 space 26a opening 27 hard rubber (elastic body)
30 proximity sensor (rotation detection sensor)
S Water or cement slurry (fluid)
A Air (fluid)
F Injection force F' Reaction force θ Inclination angle t Gap

Claims (3)

In a rotary nozzle that is used in a ground improvement device that drills and improves the ground by injecting a high-pressure fluid from the injection nozzle into the ground, and that is rotated by the reaction force of the fluid injection force,
A rotating portion having a fluid passage communicating with the fluid passage is rotatably provided around the shaft portion of the fixed portion having the fluid passage through which the fluid circulates,
part of the fluid passage of the rotating portion is obliquely formed outside the vertical plane with respect to the fluid passage of the fixed portion toward the outer peripheral side;
A tip port is provided at a tip end of a part of the inclined fluid passage, and an injection nozzle is attached to this tip port, and the rotating part is centered on the shaft part by the reaction force of the injection force of the fluid injected from the injection nozzle. rotatably,
In addition, the space formed between the fixed portion and the rotating portion is sealed, and the fluid supplied from another fluid passage formed in the fixed portion expands and deforms to brake the rotating portion. A rotary nozzle, wherein an elastic body for hanging a is provided in the opening of the space. A rotary nozzle according to claim 1,
forming another fluid passage different from the fluid passage of the shaft portion and the other fluid passages in the fixed portion;
A rotary nozzle, wherein a fluid for preventing contamination with foreign matter supplied from the separate fluid passage can be discharged from a gap between the fixed portion and the rotating portion. The rotary nozzle according to claim 1 or 2,
A rotating nozzle, wherein a rotation detection sensor for detecting a rotation state of the rotating portion is provided on the side of the fixed portion and the rotating portion facing each other.

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