JP2022151549A - Dry type spray nozzle structure - Google Patents

Abstract

To provide a dry type spray nozzle structure capable of improving kneading property of a spray material with water.SOLUTION: A dry type spray nozzle structure 10 includes: a water addition device 30 disposed at a downstream side of a material transportation hose 20 supplying a spray material 21; an inline mixer 40 disposed at a downstream side of the water addition device 30; and a first nozzle member 60 disposed at a downstream side of the inline mixer 40. The inline mixer 40 has a plurality of first, second and third mixers 42a, 42b, 42c which include large diameter parts 45a, 45b, 45c disposed at an upstream side, small diameter parts 47a, 47b, 47c disposed at a downstream side, and taper parts 46a, 46b, 46c disposed between the large diameter parts 45a, 45b, 45c and the small diameter parts 47a, 47b, 47c, and are disposed from the upstream side to the downstream side along a central axis.SELECTED DRAWING: Figure 1

Description

The present invention relates to a dry spray nozzle structure.

A nozzle structure described in Patent Document 1 is known as a nozzle structure used in a dry spraying method for constructing concrete, mortar, refractory materials, and the like. The nozzle structure described in this Patent Document 1 has a water adder, a turbulent kneading device, and a nozzle member. water is added in the turbulent kneader, the mixture of the spraying material and water is kneaded by turbulence in the turbulent kneader, and then the mixture of the spraying material and water is sprayed from the nozzle member onto the object to be worked.

Moreover, it is known to use the high-density spraying material described in patent document 2 etc. as a spraying material used for a dry-type spraying construction method.

JP-A-2004-255370 JP-A-11-223325

However, in the conventional nozzle structure described in Patent Document 1, when dry spraying is performed using the spraying material described in Patent Document 2, the spraying material and water are poorly kneaded. There was a problem that the adhesion rate of the sprayed material to the object was low.

SUMMARY OF THE INVENTION An object of the present invention is to provide a dry spray nozzle structure capable of improving the kneadability of the spray material and water with a simple structure. .

A dry spray nozzle structure according to the present invention includes a water additive provided downstream of a material supply pipe for supplying a spray material, an inline mixer provided downstream of the water additive, and a downstream of the inline mixer. The in-line mixer includes a large diameter portion provided upstream, a small diameter portion provided downstream, and a taper provided between the large diameter portion and the small diameter portion. and a plurality of conical members provided in series from the upstream side to the downstream side along the central axis.

Further, the downstream end portion of the small diameter portion may be provided with a tapered surface that reduces the inner diameter toward the downstream side.
Also, the small diameter portion may have a straight portion extending along the direction in which the central axes of the plurality of conical members extend and having a constant inner diameter.
Also, the in-line mixer may be made of cemented carbide.
Also, the small diameter portion of the conical member on the upstream side may be inserted inside the large diameter portion of the adjacent conical member on the downstream side.
Further, the nozzle tip portion of the nozzle member may be provided with a tapered surface that decreases in inner diameter toward the downstream side.
Further, the inner diameter of the large diameter portion of the conical member may be 24 to 34 mm, and the inner diameter of the small diameter portion may be 11 to 19 mm.
Also, the inner diameter of the nozzle member may be 1.2 to 2.5 times the inner diameter of the small-diameter portion of the conical member provided on the most downstream side.
Further, the total nozzle length of the nozzle member may be 5 to 10 times the inner diameter of the nozzle member.
Also, a buffer may be provided between the water supply pipe of the water adder and the downstream end of the water adder.
Further, the length of the cushioning portion in the direction along the central axis may be 30 mm to 130 mm.

According to the present invention, an in-line mixer having a dry spray nozzle structure includes a large-diameter portion provided upstream, a small-diameter portion provided downstream, and provided between the large-diameter portion and the small-diameter portion. Since it includes a tapered portion and has a plurality of conical members provided in series from the upstream side to the downstream side along the central axis, it is possible to improve the kneadability of the spray material and water with a simple configuration. can.

It is a side cross-sectional view of a nozzle structure according to Embodiment 1 of the present invention. 2 is a side sectional view of the in-line mixer shown in FIG. 1; FIG. FIG. 2 is a side cross-sectional view showing a first mixer, a second mixer, and a third mixer of the in-line mixer shown in FIG. 1; FIG. 2 is a side sectional view of the first nozzle member shown in FIG. 1; It is a side cross-sectional view of an in-line mixer according to Embodiment 2 of the present invention. It is a side cross-sectional view of an in-line mixer according to Embodiment 3 of the present invention. It is a side cross-sectional view of an in-line mixer according to Embodiment 4 of the present invention. FIG. 11 is a side cross-sectional view of a second nozzle member according to Embodiment 5 of the present invention; It is a side cross-sectional view of a nozzle structure according to Embodiment 6 of the present invention. FIG. 10 is a side cross-sectional view of the buffer shown in FIG. 9;

Embodiment 1.
Embodiment 1 of the present invention will be described in detail below with reference to the drawings.
FIG. 1 is a side sectional view of a nozzle structure according to Embodiment 1 of the present invention. The nozzle structure 10 is used in a dry spraying method, which is a method of adding water to a powdery spraying material at the operator's hand, kneading the mixture of the material and water, and then spraying it onto the object to be applied. Nozzle structure. The nozzle structure 10 includes a water adder 30 connected to a material transport hose 20 for transporting a powdered spray material 21 from the upstream side to the nozzle structure 10 by means of compressed air, and a water adder 30 provided downstream of the water adder 30. An in-line mixer 40 for kneading the spraying material 21 with water to form a mixture, and a first nozzle member 60 provided downstream of the in-line mixer 40 for spraying the kneaded mixture are provided. The first nozzle member 60 is made of SUS304.

The in-line mixer 40 is also called a static mixer, and is a mixer that agitates and kneads materials by changing the flow velocity and pressure of the materials passing through due to changes in internal cross-sectional area. In the following description of the nozzle structure 10, the upstream side refers to the side closer to the material transport hose 20, and the downstream side refers to the side closer to the nozzle tip of the first nozzle member 60. As shown in FIG. Also, the material transport hose 20 constitutes a material supply pipe.

The material transport hose 20 is connected to the sleeve 32 of the water adder 30 via an adapter socket 31 of the water adder 30 . A water adder inlet 34 is connected to the downstream side of the sleeve 32 . A water supply pipe 33 that opens in a direction perpendicular to the axial direction of the central axis A of the nozzle structure 10 and is connected to a water supply hose (not shown) is connected to the water addition device inlet 34 . A water adder outlet 35 is connected to the downstream side of the water adder inlet 34 .

A first mixer 42a, a second mixer 42b, and a third mixer 42c, which constitute the in-line mixer 40, are connected to the downstream side of the water addition device outlet 35 in this order from the upstream side. Outside the first mixer 42a, the second mixer 42b, and the third mixer 42c, a mixer holder 41 is provided for holding the first mixer 42a, the second mixer 42b, and the third mixer 42c in a mutually connected state. there is A flat rubber packing 43 and an O-ring 44 are inserted between the water adder outlet 35 and the first mixer 42a to prevent leakage of the spray material 21 and water. The first mixer 42a, the second mixer 42b, and the third mixer 42c constitute conical members.

A first nozzle member 60 is connected downstream of the third mixer 42c. The first nozzle member 60 has a nozzle tip portion 61 and a nozzle rear end portion 62 . A flat rubber packing 43 is inserted between the third mixer 42c and the nozzle rear end portion 62 to prevent leakage of the spray material 21 and water.

The material transport hose 20, the adapter socket 31, the sleeve 32, the water adder inlet 34, the water adder outlet 35, the first mixer 42a, the second mixer 42b, the third mixer 42c and the first nozzle member 60 are part of the nozzle structure 10. They are arranged along the direction of the central axis A and communicate with each other. It should be noted that the total length of the nozzle structure 10 is preferably less than 600 mm in order to improve work efficiency when spraying in a narrow space.

FIG. 2 is a side sectional view showing the in-line mixer 40. FIG. 3 is a side sectional view showing the first mixer 42a, the second mixer 42b, and the third mixer 42c of the in-line mixer 40. FIG. The first mixer 42a, the second mixer 42b, and the third mixer 42c are made of tungsten carbide, which is a cemented carbide. A large-diameter portion 45a having an inner diameter of B1 is provided on the upstream side of the first mixer 42a. A small-diameter portion 47a having an inner diameter C1 smaller than the inner diameter B1 of the large-diameter portion 45a is provided on the downstream side of the first mixer 42a. Further, a tapered portion 46a is provided between the large diameter portion 45a and the small diameter portion 47a of the first mixer 42a.

The second mixer 42b and the third mixer 42c have the same shape as the first mixer 42a. That is, the second and third mixers 42b and 42c are provided with large diameter portions 45b and 45c having an inner diameter of B1 on the upstream side. Small diameter portions 47b and 47c having an inner diameter C1 smaller than the inner diameter B1 of the large diameter portions 45b and 45c are provided downstream of the second and third mixers 42b and 42c. Further, tapered portions 46b, 46c are provided between the large diameter portions 45b, 45c and the small diameter portions 47b, 47c of the second and third mixers 42b, 42c. As shown in FIG. 3, the axial length L1 along the central axis A of the first, second and third mixers 42a, 42b and 43c is preferably 20 mm or more.

2 and 3 again, the inner diameter B1 of the large diameter portions 45a, 45b, 45c of the first, second, and third mixers 42a, 42b, 42c is preferably within the range of 24 to 34 mm, and more It is preferably within the range of 24-26 mm. The inner diameter C1 of the small diameter portions 47a, 47b, 47c of the first, second, and third mixers 42a, 42b, 42c is preferably within the range of 11 to 19 mm, more preferably within the range of 14 to 16 mm. be. That is, the ratio of the inner diameter B1 of the large diameter portions 45a, 45b, 45c to the inner diameter C1 of the small diameter portions 47a, 47b, 47c of the first, second, and third mixers 42a, 42b, 42c is preferably 0.8 or less. .

The small diameter portion 47a of the first mixer 42a is located inside the large diameter portion 45b of the second mixer 42b. The small diameter portion 47b of the second mixer 42b is located inside the large diameter portion 45c of the third mixer 42c. That is, in the direction in which the central axis A of the in-line mixer 40 extends, the first mixer 42a partially overlaps the second mixer 42b, and the second mixer 42b partially overlaps the third mixer 42c.

Inside the small-diameter portions 47a, 47b, 47c of the first, second, and third mixers 42a, 42b, 43c, there extend along the direction in which the central axis A extends, and have a predetermined axial length M1 and a constant inner diameter C1. and straight portions 48a, 48b, 48c are formed. The length M1 of the straight portions 48a, 48b, 48c is preferably 4.5 mm or less. The straight portions 48a, 48b, 48c constitute straight portions.

At each downstream end of the first, second, and third mixers 42a, 42b, and 43c, the diameter is increased downstream so that the inner peripheral side is located further downstream than the outer peripheral side in the radial direction. Downstream end portions 49a, 49b, 49c, which are tapered surfaces that decrease, are formed. Specifically, each of the downstream ends 49a, 49b, and 49c has a tapered surface forming an angle D1, which is an acute angle with respect to an imaginary plane extending in a direction perpendicular to the direction in which the central axis A extends. formed. Also, the angle D1 is preferably 4° or more.

4 is a side sectional view of the first nozzle member 60. FIG. The first nozzle member 60 has a nozzle tip portion 61 on the downstream side and a nozzle rear end portion 62 on the upstream side. The nozzle tip portion 61 is a tapered surface whose diameter decreases toward the downstream side so that the inner peripheral side is located further downstream than the outer peripheral side in the radial direction. Specifically, the nozzle tip portion 61 is formed with a tapered surface forming an acute angle E1 with respect to a virtual plane extending in a direction perpendicular to the direction in which the central axis A extends. Also, the angle E1 is preferably 4° or more.

The nozzle rear end portion 62 is configured to be connectable to the downstream side of the inline mixer 40 . The inner diameter of the first nozzle member 60 is formed to have a constant inner diameter F<b>1 except for the joint portion of the nozzle rear end portion 62 with the in-line mixer 40 . The inner diameter F1 is preferably 1.2 to 2.5 times the inner diameter C1 of the small diameter portion 47c of the third mixer 42c (see FIG. 3), ie in the range of 13.2 to 47.5 mm. Further, the axial nozzle length N1 of the first nozzle member 60 is preferably 5 to 10 times the inner diameter F1 of the first nozzle member 60. As shown in FIG.

Next, the operation of the nozzle structure 10 according to Embodiment 1 will be described.
As shown in FIG. 1, when dry spraying of the spray material 21 is carried out by means of the nozzle structure 10, the material transport is carried out in a material storage member (not shown) of a known dry spray machine in which the spray material 21 is stored. A hose 20 is connected. As spraying material, any known spraying material for dry spraying is used. A known dry sprayer water supply device (not shown) is connected to the water supply pipe 33 of the water adder 30 .

Next, when the dry spraying machine is driven by the operator's operation, the spraying material 21 is transported from the material containing member by compressed air, and water is added via the downstream adapter socket 31 and sleeve 32 from the material transporting hose 20. It flows into the water adder inlet 34 of vessel 30 . In the water adder 30, the spraying material 21 transported from upstream and the water supplied from the water supply device are mixed. The mixture of spray material 21 and water is then conveyed to in-line mixer 40 by compressed air.

The mixture of spray material 21 and water transported to in-line mixer 40 enters first mixer 42a. As shown in FIG. 2, when the mixture of the spray material 21 and water passes through the first mixer 42a, the change in the cross-sectional area of the first mixer 42a due to the change in the inner diameter of the tapered portion 46a changes the flow velocity and pressure. , a turbulent flow is generated inside the second mixer 42a, and the mixture is stirred and kneaded inside the first mixer 42a and transported to the second mixer 42b. Next, in the second mixer 42b as well, when the mixture of the spray material 21 and water passes, the change in the cross-sectional area of the second mixer 42b due to the change in the inner diameter of the tapered portion 46b causes the mixture of the spray material 21 and water to Turbulent flow is generated inside the second mixer 42b due to changes in flow velocity and pressure, and the mixture is stirred and kneaded inside the second mixer 42b and transported to the third mixer 42c. Next, in the third mixer 42c as well, when the mixture of the spray material 21 and water passes, the change in the cross-sectional area of the third mixer 42c due to the change in the inner diameter of the tapered portion 46c causes the mixture of the spray material 21 and water to Since the flow velocity and pressure change, turbulent flow is generated inside the third mixer 42c, and the mixture is stirred and kneaded inside the third mixer 42c.

Next, the mixture of the spray material 21 and water that has passed through the third mixer 42c is transported to the first nozzle member 60 by compressed air as shown in FIGS. Then, the mixture of the spray material 21 and water is transported inside the first nozzle member 60 from the nozzle rear end portion 62 of the first nozzle member 60 to the nozzle tip portion 61, is discharged from the nozzle tip portion 61, and is sprayed. Sprayed on the target.

In the first embodiment, as shown in FIG. 2, the in-line mixer 40 has a total of three mixers, namely the first, second and third mixers 42a, 42b and 42c, so that the mixture of the spray material 21 and water can be sufficiently stirred and kneaded. Further, in the first embodiment, the inner diameter B1 of the large diameter portions 45a, 45b, 45c of the first, second, and third mixers 42a, 42b, 42c is preferably within the range of 24 to 34 mm, more preferably is within the range of 24 to 26 mm, and the inner diameter C1 of the small diameter portions 47a, 47b, and 47c of the first, second, and third mixers 42a, 42b, and 42c is preferably within the range of 11 to 19 mm, more preferably is in the range of 14 to 16 mm, strong turbulence is generated inside the first, second and third mixers 42a, 42b and 42c, and the mixture of the spray material 21 and water is sufficiently stirred. , can be kneaded. Therefore, the adhesion rate of the spraying material 21 to the spraying target is improved, dust generation is reduced, and slurry dripping from the nozzle tip portion 61 of the first nozzle member can be reduced.

In the general dry spraying method, in order to promote mixing of the spraying material and water, reduce dust generation, and achieve a high adhesion rate to the sprayed object, the axis of the nozzle member The longer the nozzle length in the direction, the better. However, when a long nozzle member is used, the sprayed material generally tends to aggregate in a short period of time. There was a problem of deterioration of workability in On the other hand, in the nozzle structure 10 according to Embodiment 1, the spray material 21 and water are sufficiently mixed in the in-line mixer 40, so that the overall lengths of the first nozzle member 60 and the nozzle structure 10 are shortened. It is possible to thoroughly mix the spray material 21 and water in a short time.

Moreover, when employ|adopting a known SNG construction method as a spraying construction method, it was necessary to employ|adopt a suitable spraying material for an SNG construction method. Furthermore, when the SNG construction method is adopted, it is necessary to provide a device for pumping the coarse grain portion and a device for pumping the slurry containing the fine powder, and there is a problem that the scale of the device increases. On the other hand, when a known wet spraying method is used as a spraying method, a hardener separation system cannot be used, and the sprayed material mixed with water passes through the hose. Compared to the dry spraying method, there is a problem that the weight of the hose during work is increased, and the workload of the worker is heavy. Furthermore, when adding the curing agent at the nozzle portion, a pump for adding the curing agent is required, which increases the scale of the equipment and may cause poor mixing. On the other hand, the nozzle structure 10 according to the first embodiment does not require the spraying material to be divided and pumped like the SNG method, and prevents poor mixing of the spraying material 21 while maintaining the simplicity of the dry spraying method. can be prevented, and a mixed material equivalent to that of the SNG construction method can be discharged.

In general, when the spray material passes through the in-line mixer of the dry spray nozzle, the spray material having a high hardness is applied particularly to the tapered portion inside the in-line mixer at the small diameter portion at the downstream end of each mixer. However, there is a problem that the tapered portion is easily worn because the is delivered while contacting at high speed due to changes in flow velocity and pressure. On the other hand, in Embodiment 1, straight portions 48a, 48b and 48c are formed in the small diameter portions 47a, 47b and 47c on the downstream side of the first, second and third mixers 42a, 42b and 42c, respectively. there is As a result, on the downstream side of the first, second and third mixers 42a, 42b and 42c, the inside of the first, second and third mixers 42a, 42b and 42c, especially the tapered portions 46a, 46b and 46c Since the contact of the spray material 21 is reduced, the wear of the inside of the first, second and third mixers 42a, 42b and 42c, especially the tapered portions 46a, 46b and 46c can be reduced.

Further, downstream end portions 49a, 49b, 49c of the first, second, and third mixers 42a, 42b, 42c are tapered surfaces that decrease in diameter toward the downstream side. This causes the mixture of spray material 21 and water to flow radially along each downstream end 49a, 49b, 49c as it passes through the first, second, and third mixers 42a, 42b, 42c, respectively. Outward flow can be prevented or reduced. Therefore, deposition of the mixture of the spray material 21 and water that has flowed radially outward on the inner peripheral wall surface of the first nozzle member 60 can be reduced.

Further, as shown in FIG. 4, the nozzle tip portion 61 of the first nozzle member 60 is formed with a tapered surface that decreases in diameter toward the downstream side. As a result, when the mixture of the spray material 21 and water is discharged from the first nozzle member 60 , the mixture of the spray material 21 and water flows along the nozzle tip portion 61 and the first nozzle member 60 It is possible to prevent or reduce the problem of sticking to the outer peripheral portion and the problem of solidification in a state of dripping from the nozzle tip portion 61 .

Thus, the dry spray nozzle structure 10 according to the first embodiment includes the water adder 30 provided downstream of the material transport hose 20 that supplies the spray material 21, and the water adder 30 downstream of the water adder 30. and a first nozzle member 60 provided downstream of the inline mixer 40. The inline mixer 40 includes large diameter portions 45a, 45b, and 45c provided upstream and downstream and tapered portions 46a, 46b, 46c provided between the large diameter portions 45a, 45b, 45c and the small diameter portions 47a, 47b, 47c. Since it has a plurality of first, second and third mixers 42a, 42b and 42c provided from the upstream side to the downstream side along the . can improve sexuality.

In addition, the downstream ends 49a, 49b, and 49c of the small diameter portions 47a, 47b, and 47c are provided with tapered surfaces that reduce the inner diameter toward the downstream side. Deposition on the inner peripheral wall surface of the first nozzle member 60 due to the mixture of the spray material 21 and water flowing radially outward can be reduced.

Further, the small-diameter portions 47a, 47b, 47c extend along the direction in which the central axis A of the first, second, and third mixers 42a, 42b, 42c extends, and have a straight portion with a constant inner diameter C1. Wear of the portions 46a, 46b, 46c can be reduced.

In addition, since the in-line mixer 40 is made of cemented carbide, it is possible to suppress abrasion of the inner circumference of the in-line mixer 40 due to the spray material 21 .

The small diameter portions 47a, 47b of the first and second mixers 42a, 42b on the upstream side are inserted into the large diameter portions 45b, 45c of the second and third mixers 42b, 42c adjacent to the downstream side. As a result, the contact portion between the first mixer 42a and the second mixer 42b is positioned upstream of the downstream end portion 49a of the first mixer 42a, and the contact portion between the second mixer 42b and the third mixer 42c is positioned upstream of the downstream end 49b of the second mixer 42b, the contact portion between the first mixer 42a and the second mixer 42b and the contact portion between the second mixer 42b and the third mixer 42c are sprayed. Direct collision of the mixture of the material 21 and water can be prevented, and leakage of the mixture of the spray material 21 and water from the side of the in-line mixer 40 can be reduced.

Further, since the nozzle tip portion 61 of the first nozzle member 60 is provided with a tapered surface that decreases in inner diameter toward the downstream side, the mixture of the spray material 21 and water flows along the nozzle tip portion 61. It is possible to prevent or reduce the problem of flowing and adhering to the outer peripheral portion of the first nozzle member 60 and the problem of solidifying while hanging from the nozzle tip portion 61 .

The inner diameter B1 of the large diameter portions 45a, 45b and 45c of the first, second and third mixers 42a, 42b and 42c is 24 to 34 mm, and the inner diameter C1 of the small diameter portions 47a, 47b and 47c is 11 to 19 mm. Therefore, a strong turbulent flow is generated inside the first, second and third mixers 42a, 42b and 42c, and the mixture of the spray material 21 and water can be sufficiently stirred and kneaded.

In addition, since the inner diameter F1 of the first nozzle member 60 is 1.2 to 2.5 times the inner diameter C1 of the inner diameter C1 of the small diameter portion 47c of the third mixer 42c provided most downstream, Abrasion of the inside of the first nozzle member 60 due to the mixture with water flowing in the circumferential direction inside the first nozzle member 60 immediately after being transported to the first nozzle member 60 can be suppressed.

In addition, since the total nozzle length N1 of the first nozzle member 60 is 5 to 10 times the inner diameter F1 of the first nozzle member 60, the total length of the nozzle structure 10 can be shortened while the spray discharged from the first nozzle member 60 is increased. It is possible to improve the straightness of the mixture of the spraying material 21 and water, which facilitates the spraying operation when the spraying target range is narrow.

Although in-line mixer 40 is made of tungsten carbide in the first embodiment, it may be made of other types of cemented carbide. Further, if a material having a low hardness and less abrasion of the in-line mixer 40 is used as the spraying material 21, the in-line mixer 40 may be made of a metal other than cemented carbide.

Embodiment 2.
Next, Embodiment 2 of the present invention will be described. In the following embodiments, the same reference numerals as those in FIGS. 1 to 4 of Embodiment 1 denote the same or similar components, so detailed description thereof will be omitted. The second embodiment is obtained by changing the configuration of the in-line mixer with respect to the first embodiment.
FIG. 5 is a side sectional view of in-line mixer 70 according to the second embodiment. The in-line mixer 70 has a first mixer 72a, a second mixer 72b, and a third mixer 72c in order from the upstream side. Note that the illustration of the mixer holder of the in-line mixer 70 is omitted in FIG.

A large-diameter portion 75a having an inner diameter of B2 is provided on the upstream side of the first mixer 72a. A small diameter portion 77a having an inner diameter C2 smaller than the inner diameter B2 of the large diameter portion 75a is provided on the downstream side of the first mixer 72a. Further, the first mixer 72a is provided with a tapered portion 76a between the large diameter portion 75a and the small diameter portion 77a.

The second mixer 72b and the third mixer 72c have the same shape as the first mixer 72a. That is, the second and third mixers 72b and 72c are provided with large diameter portions 75b and 75c having an inner diameter B2 on the upstream side, and small diameter portions 77b and 77c having an inner diameter C2 on the downstream side, The second and third mixers 72b, 72c are provided with tapered portions 76b, 76c between the large diameter portions 75b, 75c and the small diameter portions 77b, 77c.

The inner diameter B2 of the large diameter portions 75a, 75b, 75c of the first, second, and third mixers 72a, 72b, 72c is preferably within the range of 24 to 34 mm, more preferably within the range of 24 to 26 mm. . The inner diameter C2 of the small diameter portions 77a, 77b, 77c of the first, second, and third mixers 72a, 72b, 72c is preferably within the range of 11 to 19 mm, more preferably within the range of 14 to 16 mm. be.

The small diameter portion 77a of the first mixer 72a is positioned inside the large diameter portion 75b of the second mixer 72b. The small diameter portion 77b of the second mixer 72b is positioned inside the large diameter portion 75c of the third mixer 72c. In the direction of the central axis A of the in-line mixer 70, the length of the overlapping portion between the small-diameter portion 77a side of the first mixer 72a and the large-diameter portion 75b side of the second mixer 72 is the same as that of the first mixer 42a of the first embodiment (Fig. 2) is formed longer than the length of the overlapping portion between the small diameter portion 47a side and the large diameter portion 45c side of the second mixer 42 . In addition, the length of the overlapping portion between the small diameter portion 77b side of the second mixer 72b and the large diameter portion 75c side of the third mixer 72 is the same as the length of the small diameter portion 47b side of the second mixer 42b and the third mixer 42 of the first embodiment. is formed longer than the length of the overlapping portion with the large diameter portion 45c side.

The length M2 of the straight portions 78a, 78b, and 78c of the first, second, and third mixers 72a, 72b, and 72c is equal to the length M2 of the straight portions of the first, second, and third mixers 42a, 42b, and 42c of the first embodiment. The lengths of 48a, 48b, and 48c are shorter than the length M1.

The angle of the tapered surface of each of the downstream ends 79a, 79b, 79c of the first, second, and third mixers 72a, 72b, 72c with respect to the virtual plane extending in the direction perpendicular to the direction in which the central axis A extends. D2 is 14° or more. Other configurations are the same as those of the first embodiment.

Thus, the in-line mixer 70 according to the second embodiment has the straight portions 78a, 78b, 78c with a shorter length M2 than the length M1 of the straight portions 48a, 48b, 48c of the first embodiment. Even with a dry spray nozzle structure, the kneadability of the spray material and water in the dry spray nozzle structure can be improved.

Embodiment 3.
Next, Embodiment 3 of the present invention will be described. The third embodiment is different from the first embodiment in the number of mixers constituting the in-line mixer.
FIG. 6 is a side cross-sectional view of in-line mixer 80 according to the third embodiment. The inline mixer 80 has a first mixer 82a and a second mixer 82b in order from the upstream side. The second mixer 82b is connected to the first nozzle member 60. As shown in FIG. Note that the illustration of the mixer holder of the in-line mixer 80 is omitted in FIG.

A large-diameter portion 85a having an inner diameter of B3 is provided on the upstream side of the first mixer 82a. A small diameter portion 87a having an inner diameter C3 smaller than the inner diameter B3 of the large diameter portion 85a is provided on the downstream side of the first mixer 82a. Further, the first mixer 82a is provided with a tapered portion 86a between the large diameter portion 85a and the small diameter portion 87a.

The second mixer 82b has the same shape as the first mixer 82a. That is, the second mixer 82b is provided with a large-diameter portion 85b having an inner diameter of B3 on the upstream side and a small-diameter portion 87b with an inner diameter of C3 on the downstream side. A tapered portion 86b is provided between 85b and the small diameter portion 87b.

The inner diameter B3 of the large-diameter portions 85a, 85b of the first and second mixers 82a, 82b is preferably within the range of 24-34 mm, more preferably within the range of 24-26 mm. The inner diameter C3 of the small diameter portions 87a, 87b of the first and second mixers 82a, 82b is preferably within the range of 16-24 mm, more preferably within the range of 19-21 mm. That is, the ratio of the inner diameter B1 of the large diameter portions 45a and 45b to the inner diameter C1 of the small diameter portions 87a and 87b of the first and second mixers 82a and 82b is preferably 0.75 or less.

The small diameter portion 87a of the first mixer 82a is located inside the large diameter portion 85b of the second mixer 82b.

The length M3 of the straight portions 88a, 88b of the first and second mixers 82a, 82b is equal to the length M1 of the straight portions 48a, 48b of the first and second mixers 42a, 42b (see FIG. 2) of the first embodiment. formed to a shorter length than

The angle D3 of the tapered surfaces of the downstream ends 89a and 89b of the first and second mixers 82a and 82b with respect to the virtual plane extending in the direction perpendicular to the direction in which the central axis A extends is 14° or more. be. Other configurations are the same as those of the first embodiment.

In the first embodiment, the in-line mixer 40 is composed of three mixers, ie, the first, second, and third mixers 42a, 42b, and 42c. 1st and 2nd mixers 82a and 82b. Further, the ratio of the inner diameter C3 of the small diameter portions 87a and 87b to the inner diameter B3 of the large diameter portions 85a and 85b of the first and second mixers 82a and 82b of the inline mixer 80 according to the third embodiment is ratio of the inner diameter C1 of the small diameter portions 47a, 47b, 47c to the inner diameter B1 of the large diameter portions 45a, 45b, 45c of the first, second, and third mixers 42a, 42b, 42c. Even with such a dry spray nozzle structure according to Embodiment 3, it is possible to improve the kneadability of the spray material and water in the dry spray nozzle structure.

Embodiment 4.
Next, Embodiment 4 of the present invention will be described. The fourth embodiment differs from the first embodiment in the configuration of the in-line mixer.
FIG. 7 is a side cross-sectional view of in-line mixer 90 according to Embodiment 4 of the present invention.
The in-line mixer 90 has a first mixer 92a and a second mixer 92b in order from the upstream side. The second mixer 92b is connected to the first nozzle member 60. As shown in FIG. 7, illustration of the mixer holder of the in-line mixer 90 is omitted.

A large-diameter portion 95a having an inner diameter of B4 is provided on the upstream side of the first mixer 92a. A small diameter portion 97a having an inner diameter C4 smaller than the inner diameter B4 of the large diameter portion 95a is provided on the downstream side of the first mixer 92a. Further, the first mixer 92a is provided with a tapered portion 96a between the large diameter portion 95a and the small diameter portion 97a.

The second mixer 92b has the same shape as the first mixer 92a. That is, the second mixer 92b is provided with a large-diameter portion 95b having an inner diameter of B4 on the upstream side and a small-diameter portion 97b with an inner diameter of C4 on the downstream side. A tapered portion 96b is provided between 95b and the small diameter portion 97b.

The inner diameter B4 of the large diameter portions 95a, 95b of the first and second mixers 92a, 92b is preferably within the range of 24-34 mm, more preferably within the range of 24-26 mm. The inner diameter C4 of the small diameter portions 97a and 97b of the first and second mixers 92a and 92b is preferably within the range of 11 to 19 mm, more preferably within the range of 14 to 16 mm.

The small diameter portion 97a of the first mixer 92a is located inside the large diameter portion 95b of the second mixer 92b.

The length M4 of the straight portions 98a and 98b of the first and second mixers 92a and 92b is shorter than the length M1 of the straight portions 48a and 48b of the first and second mixers 42a and 42b of the first embodiment. is formed in

The angle D4 of the tapered surfaces of the downstream ends 99a and 99b of the first and second mixers 92a and 92b with respect to the virtual plane extending in the direction perpendicular to the direction in which the central axis A extends is 14° or more. be. Other configurations are the same as those of the first embodiment.

Even with the dry spray nozzle structure according to the fourth embodiment, it is possible to improve the kneadability of the spray material and water in the dry spray nozzle structure.

Note that the configurations of the in-line mixers 40, 70, 80 and 90 in the first to fourth embodiments of the present invention are merely examples, and other configurations may be employed as appropriate. For example, although the taper angle D1 of the downstream ends 49a, 49b, and 49c in Embodiment 1 is preferably 4° or more, the angle D1 may be less than this.

Embodiment 5.
Next, Embodiment 5 of the present invention will be described. Embodiment 5 of the present invention is obtained by changing the shape of the nozzle member with respect to Embodiment 1. FIG.
FIG. 8 is a side sectional view of a second nozzle member 60a according to Embodiment 5 of the present invention. The second nozzle member 60a has a downstream nozzle tip portion 61a and an upstream nozzle rear end portion 62a. A nozzle tapered portion 63a is formed inside the nozzle rear end portion 62a such that the inner diameter F2 on the downstream side is smaller than the inner diameter F1 on the upstream side. The nozzle taper portion 63a is formed to have an inner diameter F1 on the upstream side and an inner diameter F2 on the downstream side. The downstream inner diameter F2 is preferably 21 mm or less. Further, the nozzle taper portion 63a is formed to form an acute angle G1 with respect to an imaginary straight line extending parallel to the central axis A. As shown in FIG. Angle G1 is preferably greater than or equal to 10°. The second nozzle member 60a is made of SUS304.

A portion of the second nozzle member 60a from the nozzle rear end portion 62a to the nozzle tip portion 61a is formed to have a constant inner diameter F2. The nozzle tip portion 61a is a tapered surface whose diameter decreases toward the downstream side so that the inner peripheral side is located further downstream than the outer peripheral side in the radial direction. Specifically, the nozzle tip portion 61a is formed with a tapered surface forming an acute angle E2 with respect to a virtual plane extending in a direction perpendicular to the direction in which the central axis A extends. Also, the angle E2 is preferably 4° or more. Further, the axial nozzle length N2 of the second nozzle member 60a is preferably 5 to 10 times the inner diameter F2 of the second nozzle member 60a.

Thus, the axial nozzle length N2 of the second nozzle member 60a of the nozzle structure according to the fifth embodiment is smaller than the inner diameter F1 of the first nozzle member 60 of the first embodiment. Since it is 5 to 10 times the inner diameter F2 on the downstream side of the nozzle member 60a, the length of the entire nozzle structure can be shortened compared to the first embodiment.

The configuration of the first nozzle member 60 in Embodiments 1 to 4 and the configuration of the second nozzle member 60a in Embodiment 5 of the present invention are merely examples, and other configurations may be employed as appropriate. For example, although the taper angle E1 of the nozzle tip portion 61 of the first nozzle member 60 in Embodiment 1 is preferably 4° or more, the angle E1 may be less than this.

Further, although the first nozzle member 60 in Embodiments 1 to 4 and the second nozzle member 60a in Embodiment 5 of the present invention are made of SUS304, they are made of aluminum alloy in order to reduce the weight of the nozzle members, for example. It may be formed of any metal, such as by forming.

Further, in the nozzle structures according to Embodiments 2 to 5 of the present invention, when the mixture of the spray material 21 and water is sprayed onto the experimental wall surface, the An experiment was conducted to measure the adhesion rate (adhesion rate), which is the ratio of the weight of the mixture of the sprayed material 21 and water adhering to the experimental wall surface to the weight of the mixture of the sprayed material 21 and water. The results of this experiment are described below using Table 1. The spray material 21 used in this experiment contains 90% silicon carbide (SiC). In addition, configurations not described in the explanation of Experiment Nos. 1 to 5 below are configurations common to Experiment Nos. 1 to 5.

In Experiment No. 1, the inner diameter B1 of the large-diameter portions 75a, 75b, and 75c of the first, second, and third mixers 72a, 72b, and 72c of the in-line mixer 70 (see FIG. 5) of the second embodiment is set to 25 mm, The inner diameter C1 of the small diameter portions 77a, 77b, 77c is set to 15 mm, the angle D2 of the downstream end portions 79a, 79b, 79c is set to 15°, the inner diameter F1 of the first nozzle member 60 (see FIG. 4) is set to 25 mm, and the first This is a case where the total length N1 of the nozzle in the axial direction of the nozzle member 60 is set to 150 mm, and the angle E1 of the tapered surface of the nozzle tip portion 61 is set to 5°. The adhesion rate in Experiment No. 1 is 85.3%.

In Experiment No. 2, the in-line mixer 70 is the same as Experiment No. 1, but the second nozzle member 60a of Embodiment 5 is used instead of the first nozzle member 60, and the inner diameter of the upstream side of the second nozzle member 60a is F1 is 25 mm, the downstream inner diameter F2 is 20 mm, the angle G1 of the nozzle taper portion 63a is 10°, the total length N2 of the nozzle in the axial direction of the second nozzle member 60a is 120 mm, and the angle of the tapered surface of the nozzle tip portion 61a. This is the case where E2 is set to 5°. The adhesion rate in Experiment No. 2 is 90.5%.

In Experiment No. 3, the inline mixer 80 of Embodiment 3 was used, the inner diameter B3 of the large diameter portions 85a and 85b of the first and second mixers 82a and 82b of the inline mixer 80 was set to 25 mm, and the small diameter portions 87a and 87b of the inline mixer 80 This is a case where the inner diameter C3 is set to 20 mm, the angle D3 between the downstream end portions 89a and 89b is set to 15°, and the same second nozzle member 60a as in Experiment No. 2 is used. The adhesion rate in Experiment No. 3 is 80.5%.

Experiment No. 4 used the inline mixer 90 of Embodiment 4, set the inner diameter B4 of the large diameter portions 95a and 95b of the first and second mixers 92a and 92b of the inline mixer 90 to 25 mm, and set the small diameter portions 97a and 97b of the inline mixer 90 to 25 mm. This is a case where the inner diameter C4 is set to 15 mm, the angle D3 between the downstream end portions 89a and 89b is set to 15°, and the same second nozzle member 60a as in Experiment No. 2 is used. The adhesion rate in Experiment No. 3 is 77.0%.

Experiment No. 5 is a case of using the same second nozzle member 60a as in Experiment No. 2 without using an in-line mixer for comparison. The adhesion rate in Experiment No. 5 is 76.1%.

Comparing Experiment Nos. 2 to 4 with Experiment No. 5, Experiment No. 2 using an in-line mixer had an adhesion rate of 90.5%, and Experiment No. 3 had an adhesion rate of 80.5%. In the case of No. 4, the adhesion rate was 77.0%, and in Experiment No. 5, in which the in-line mixer was not used, the adhesion rate was 76.1%. It was found that Experiment Nos. 2 to 4, which used a mixer, had a better adhesion rate.

Comparing Experiment No. 1 and Experiment No. 2, the adhesion rate in Experiment No. 1 using the first nozzle member 60 was 85.3%, whereas the adhesion rate in Experiment No. 2 using the second nozzle member 60a was 85.3%. The deposition rate was 90.5%, and when the same in-line mixer 70 was used, the test number 2 using the second nozzle member 60a had a better deposition rate.

Comparing Experiment No. 2, Experiment No. 3, and Experiment No. 4, the adhesion rate when the same second nozzle member 60a is used is 90.5 in Experiment No. 2 using the in-line mixer 70. %, the adhesion rate in the case of experiment number 3 using inline mixer 80 was 80.5%, the adhesion rate in the case of experiment number 4 using inline mixer 90 was 77.0%, and inline mixer 70 was used. An experimental result was obtained that the adhesion rate was the best in the case.

Embodiment 6.
Next, Embodiment 6 of the present invention will be described. Embodiment 6 of the present invention differs from Embodiment 1 in that a buffer is provided between the water supply pipe of the water addition device and the downstream end of the water addition device.
FIG. 9 is a side sectional view of a nozzle structure according to Embodiment 6. FIG. A buffer portion 36 is provided between the water additive inlet 34 provided with the water supply pipe 33 and the water additive outlet 35, which is the downstream end of the water additive 30, of the water additive 30 of the nozzle structure 10a. is formed. That is, the buffer section 36 is formed between the water supply pipe 33 and the downstream end of the water adder 33 . The cushioning portion 36 has a first diameter portion 36a, a second diameter portion 36b, and a third diameter portion 36c having different inner diameters from the upstream side in the direction extending along the central axis A. As shown in FIG.

FIG. 10 is a side sectional view of the buffer portion 36 shown in FIG. A first diameter portion 36 a of the buffer portion 36 is connected to the water supply pipe 33 and the water adder inlet 34 . Between the first diameter portion 36a and the water adder inlet 34, the spray material 21 (see FIG. 9) and a flat rubber packing 43 for preventing water leakage are inserted. In addition, the first diameter portion 36a has a uniform inner diameter in the direction extending along the central axis A. As shown in FIG.

A second diameter portion 36b is connected to the downstream side of the first diameter portion 36a. The second diameter portion 36b has an inner diameter that is larger than that of the first diameter portion 36a and uniform in the direction along the central axis A. As shown in FIG. A third diameter portion 36c is connected to the downstream side of the second diameter portion 36b. The third diameter portion 36c has a tapered inner diameter that continuously decreases toward the downstream side in the direction extending along the central axis A. As shown in FIG. The first mixer 42a of the in-line mixer 40 is connected to the downstream side of the third diameter portion 36c. The tapered inner diameter of the third diameter portion 36c forms an inner diameter that is continuous with the inner diameter of the tapered portion 46a of the first mixer 42a. A flat rubber packing 43 is inserted between the third diameter portion 36c and the first mixer 42a.

From the upstream end portion 37a of the inner diameter portion of the first diameter portion 36a, which is the most upstream position of the connection position between the first diameter portion 36a of the buffer portion 36 and the water supply pipe 33, the third diameter portion 36c and the third diameter portion 36c are connected. The buffer portion 36 is formed such that the distance H2 between the inner diameter portion of the third diameter portion 36c and the downstream end portion 37c, which is the contact portion with the first mixer 42a, is preferably 30 mm to 130 mm. Preferably, the buffer portion 36 is formed such that the distance H2 is 50 mm to 130 mm. The distance H2 constitutes the substantial length of the inner diameter portion in the direction along the central axis A of the buffer portion 36 from the water supply pipe 33 to the downstream end portion 37c. Other configurations are the same as those of the first embodiment.

In addition, in the water addition device 30 and the in-line mixer 40 of Embodiment 1 shown in FIG. 2, the distance H1 from the most upstream position of the connection position with the water supply pipe 33 to the upstream end of the first mixer 42a is formed to be less than 30 mm.

Next, operation of the nozzle structure 10a according to the sixth embodiment will be described. When dry spraying of the spraying material 21 is carried out by the nozzle structure 10a shown in FIG. The spray material 21 that has flowed into the water adder inlet 34 of the adder 30 is added with the water supplied from the water supply device and flowed into the water supply pipe 33 , and mixed in the water adder 30 . The mixture of spray material 21 and water is then conveyed to in-line mixer 40 by compressed air. Next, the mixture of the spray material 21 and water transported to the in-line mixer 40 is stirred and kneaded inside and transported to the first nozzle member 60 .

Next, advantages of the nozzle structure 10a of Embodiment 6 will be described. Before the dry spraying is performed on the tapered portions 46a, 46b and 46c formed inside the first mixer 42a, the second mixer 42b and the third mixer 42c of the in-line mixer 40 of the nozzle structure 10a of Embodiment 6. and the wear state after dry spraying with respect to the state before dry spraying in the tapered portions 46a, 46b and 46c of the nozzle structure 10 of the first embodiment. compared. Then, the state of wear of the tapered portions 46a, 46b and 46c of the sixth embodiment after the dry spraying compared to before the dry spraying is the same as that of the tapered portions 46a, 46b and 46c of the first embodiment. The wear condition after dry spraying was lighter than before.

That is, since the water adder 30 of the nozzle structure 10a according to the sixth embodiment has the buffer portion 36, the nozzle structure 10a of the sixth embodiment is different from the nozzle structure 10 of the first embodiment. As a result, wear of the tapered portions 46a, 46b and 46c of the in-line mixer 40 after dry spraying is reduced.

Thus, since the nozzle structure 10a according to Embodiment 6 has the buffer portion 36 between the water supply pipe 33 of the water adder 30 and the downstream end portion 37c of the water adder 30, the in-line Wear of the tapered portions 46a, 46b and 46c of the mixer 40 can be reduced.

Further, since the distance H2 of the buffer portion 36 in the direction along the central axis A is 30 mm to 130 mm, it is possible to more effectively reduce the wear of the tapered portions 46a, 46b and 46c of the inline mixer 40. .

20 material transport hose (material supply pipe), 30 water adder, 33 water supply pipe, 36 buffer, 37c downstream end, 40 in-line mixer, 42a first mixer (conical member), 42b second mixer (conical 42c Third mixer (conical member) 45a, 45b, 45c Large diameter portion 46a, 46b, 46c Tapered portion 47a, 47b, 47c Small diameter portion 48a, 48b, 48c Straight portion (linear portion) , 49a, 49b, 49c downstream end, 60 first nozzle member, 60a second nozzle member, 61, 61a nozzle tip, 70 in-line mixer, 72a first mixer (conical member), 72b second mixer (conical 72c Third mixer (conical member) 75a, 75b, 75c Large diameter portion 76a, 76b, 76c Tapered portion 77a, 77b, 77c Small diameter portion 78a, 78b, 78c Straight portion (linear portion) , 79a, 79b, 79c downstream end portion 80 in-line mixer 82a first mixer (conical member) 82b second mixer (conical member) 85a, 85b large diameter portion 86a, 86b taper portion 87a, 87b small diameter portion 88a, 88b straight portion (linear portion) 89a, 89b downstream end portion 90 in-line mixer 92a first mixer (conical member) 92b second mixer (conical member) 95a, 95b large Diameter portion 96a, 96b Tapered portion 97a, 97b Small diameter portion 98a, 98b Straight portion (linear portion) 99a, 99b Downstream end portion A Central axis B1, B2, B3, B4 Inside diameter C1, C2, C3, C4 inner diameter, N1, N2 nozzle full length.

Claims (11)

a water adder provided downstream of the material supply pipe for supplying the spraying material;
an in-line mixer provided downstream of the water adder;
A nozzle member provided downstream of the inline mixer,
The in-line mixer includes a large-diameter portion provided upstream, a small-diameter portion provided downstream, and a tapered portion provided between the large-diameter portion and the small-diameter portion. A dry spray nozzle structure having a plurality of conical members arranged in series from upstream to downstream along. 2. The dry spray nozzle structure according to claim 1, wherein the downstream end portion of the small diameter portion is provided with a tapered surface that decreases in inner diameter toward the downstream side. The dry spray nozzle structure according to claim 1 or 2, wherein the small diameter portion has a straight portion extending along the direction in which the central axes of the plurality of conical members extend and having a constant inner diameter. The dry spray nozzle structure according to any one of claims 1 to 3, wherein the in-line mixer is made of cemented carbide. The dry spraying according to any one of claims 1 to 4, wherein the small diameter portion of the conical member on the upstream side is inserted inside the large diameter portion of the adjacent conical member on the downstream side. nozzle structure. The dry spray nozzle structure according to any one of claims 1 to 5, wherein the nozzle tip portion of the nozzle member is provided with a tapered surface that decreases in inner diameter toward the downstream side. The dry spray nozzle structure according to any one of claims 1 to 6, wherein the large diameter portion of the conical member has an inner diameter of 24 to 34 mm, and the small diameter portion has an inner diameter of 11 to 19 mm. The dry type according to any one of claims 1 to 7, wherein the inner diameter of the nozzle member is 1.2 to 2.5 times the inner diameter of the small diameter portion of the conical member provided on the most downstream side. Spray nozzle structure. The dry spray nozzle structure according to any one of claims 1 to 8, wherein the total nozzle length of the nozzle member is 5 to 10 times the inner diameter of the nozzle member. The dry spray nozzle structure according to any one of claims 1 to 9, further comprising a buffer portion between the water supply pipe of the water adder and the downstream end of the water adder. 11. The dry spray nozzle structure according to claim 10, wherein the buffer portion has a length of 30 mm to 130 mm in the direction along the central axis.

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