JP2007231730A - Mortar or concrete spraying device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mortar or concrete spraying device capable of smoothly and positively spraying mortar or concrete even in long-distance conveyance. <P>SOLUTION: The mortar or concrete spraying device D for separately force-feeding aggregate 1 and cement milk 6 constituting mortar M or concrete and then mixing them to spray a mixture comprises a cement milk delivery pipe 10 for conveying the cement milk 6, and a conveying pipe 8 for conveying the aggregate 1. The conveying pipe 8 has a cement milk lead-in part 9 to which the downstream end of the cement milk delivery pipe 10 is connected. The cement milk lead-in part 9 is formed with a tapered portion 9a enlarged in inner diameter toward the downstream side, and the cement milk delivery pipe 10 is connected to the tapered portion 9a so that the flow direction of the aggregate 1 and the flow direction of the cement milk 6 form an acute angle in a longitudinal section. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a mortar or concrete spraying device.

When mortar or concrete is sprayed on a formwork pre-formed on a slope at a high place to form a grid-like formwork, water, cement and aggregate are kneaded in advance to apply the spraying material. In a conventional mortar or concrete spraying device that is formed and pumps the spraying material using a transport pipe, the spraying resistance of the spraying material passing through the transport pipe is very large, and the discharge amount of the spraying material as expected (Pressure) could not be obtained, and therefore, high-pressure spraying construction and spraying construction using aggregates having a large particle size were difficult or impossible.

Therefore, in order to efficiently perform spraying work at a higher place or using a larger aggregate, the applicant of the present invention, as shown in Patent Document 1, cement milk and aggregate constituting mortar or concrete. We are developing a separate pumping system spraying device that pumps separately.

For example, the separate pressure-feed type spraying device moves the sand as aggregate through a conveying pipe having a length of about 400 m by compressed air, and mixes it with cement milk at a position of about 10 m just before the spraying nozzle. A mortar or concrete is obtained, and an operator supported by a lifeline sprays mortar or concrete against the mold while holding the spray nozzle, thereby forming a grid-like frame. .

According to the separate pressure feed spraying device, since the cement milk and the aggregate are separately pumped to the vicinity of the front of the spray nozzle, the pressure resistance of the aggregate in the transport pipe is reduced, so the discharge amount (pressure) is reduced. It can be made larger, and mortar or concrete can be sprayed onto a high position, or sprayed using aggregates having a large particle size.
JP 2001-248164 A Utility Model Registration No. 2509314

However, in the separate pressure feeding type mortar or concrete spraying apparatus, there is a problem that the aggregate before and after being mixed with cement milk is likely to be clogged in the transport pipe, and the spraying construction cannot be performed smoothly.

The applicant believes that one of the causes of the clogging is an aggregate pumping machine for pumping the aggregate. That is, in the mortar or concrete spraying apparatus, an aggregate pumping machine (civil engineering spraying machine) as shown in Patent Document 2 is used. In the aggregate pumping machine, however, a pumping tube from a lower pot is used. Because the amount of spray material sent to the
It is considered that the spraying material pumped in the (conveying pipe) pulsates, and this pulsation caused the clogging.

In addition, as another possible cause of the clogging, in the mortar or concrete spraying device, when cement milk is added to the aggregate flowing in the conveyance pipe, the volume and weight of the flowing aggregate rapidly increase. It is conceivable that the conveying speed is lowered, and thereby the inside of the conveying tube is blocked by the aggregate and cement milk.

Therefore, mortar or concrete cannot be transported and sprayed to places where the carry-on of machines is restricted, such as near the summits of steep mountainous areas, and the slopes in such places are those using mortar or concrete. It was left without construction for surface protection.

The present invention has been made in consideration of the above-described matters, and its purpose is to spray mortar or concrete that enables smooth and reliable spraying of mortar or concrete even for long-distance conveyance. Is to provide a device.

In order to achieve the above object, the mortar or concrete spraying apparatus of the present invention is a mortar or concrete spraying apparatus in which the aggregate and cement milk constituting the mortar or concrete are separately pumped and then mixed and sprayed. A cement milk feed pipe for transporting the cement milk and a transport pipe for transporting the aggregate, wherein the transport pipe is connected to a downstream end of the cement milk feed pipe The cement milk introduction portion is formed with a tapered portion having an inner diameter that increases toward the downstream side, and the direction in which the aggregate flows and the direction in which the cement milk flows is longitudinally cut with respect to the tapered portion. The cement milk delivery pipe is connected so as to have an acute angle on the surface (Claim 1).

Further, it is preferable that the cement milk delivery pipe is connected at an angle to the tapered portion so that the cement milk flowing into the transport pipe draws a spiral along the inner wall of the transport pipe. (Claim 2).

Also, a mortar or concrete spraying device for separately feeding aggregate and cement milk constituting mortar or concrete, and then mixing and spraying, and downstream end of a transport pipe for transporting the mixed aggregate and cement milk Nozzle portion is provided, and this nozzle portion has, in order from the upstream side, a widened portion whose inner diameter increases toward the downstream side and a throttle portion whose inner diameter decreases toward the downstream side. The inner diameter of the downstream end may be configured to be equal to or slightly larger than the inner diameter of the transport pipe.
.

According to the present invention having the above-described configuration, it is possible to provide a mortar or concrete spraying apparatus that enables smooth and reliable spraying of mortar or concrete even for long-distance conveyance. .

In the invention according to claim 1, the following effects can be obtained. That is, the cement milk introduction portion in the transport pipe is not formed with a tapered portion having an inner diameter that increases toward the downstream side, and the cement milk introduction portion has a cylindrical shape with the same diameter from the upstream side to the downstream side. In the spraying device, the cement milk introduction part, which is cylindrical rather than tapered, was easy to hit the aggregate conveyed through the conveyance pipe. It was difficult to realize conveyance.

Further, in the conventional spraying device, the cement milk discharged to the cement milk introduction section has a curtain shape, and the cement milk curtain becomes the resistance of the compressed air flowing in the transport pipe to transport the aggregate. As a result, the conveyance force of the compressed air may be reduced, causing a blockage in the conveyance pipe.

Therefore, in order to prevent the cement milk introduced into the cement milk introduction part from becoming a curtain shape, the cement milk delivery pipe is connected to the cement milk introduction part at an acute angle,
It is conceivable to introduce cement milk along the inner wall of the cement milk introduction part by reducing the angle formed by the cement milk introduction direction with respect to the aggregate conveyance direction. Since the part was cylindrical rather than tapered, the area of the opening for introducing cement milk from the cement milk delivery pipe formed in this cement milk introduction part became large, and the inside of the transport pipe from this opening Compressed air flowing through the air could easily enter, which could hinder the introduction of cement milk.

However, in the invention according to claim 1, a tapered portion having a larger inner diameter is formed on the downstream side, and the cement milk delivery pipe is connected to the tapered portion, so that the inside of the conveying pipe is conveyed. Aggregate is less likely to hit directly, wear of the cement milk introduction part is reduced, and continuous conveyance for a long time can be realized.

Further, in the invention according to claim 1, the cement milk delivery pipe is connected to the cement milk introduction portion at an acute angle, and the angle formed by the cement milk introduction direction with respect to the aggregate conveyance direction is reduced. Since the part to which the delivery pipe is connected is a tapered part, the area of the opening for introducing cement milk from the cement milk delivery pipe formed in this tapered part can be made smaller than before, thereby Further, it is possible to prevent the compressed air flowing through the inside of the transport pipe from entering the opening, and the cement milk can be smoothly introduced.

Further, in the invention according to claim 2, the cement milk is introduced along the inner wall of the cement milk introduction part, does not become a curtain shape, and is compressed air flowing in the conveyance pipe to convey the aggregate. Therefore, it is possible to effectively prevent cement milk from reducing the conveying force of compressed air and causing clogging in the conveying pipe.

In the invention according to claim 3, the following effects can be obtained. That is, in the conventional spraying device in which the diameter of the tip of the nozzle portion is narrowed to be smaller than the inner diameter of the transfer tube, the restriction of the tip of the nozzle portion is the spray material (aggregate and cement that has been conveyed in the transfer tube). Milk) resistance, the compressed air was de-energized, and the aggregate being transported was sometimes clogged in the transport tube. Also,
The silt that had been separated from the spray material in the transport pipe immediately before spraying was mixed with the spray material again, making it difficult to construct using high-quality mortar or concrete.

However, in the invention according to claim 3, the diameter of the tip of the nozzle part is approximately the same as the inner diameter of the transport pipe,
Since it is squeezed so as to be slightly larger, it does not become the resistance of the spray material that has been transported in the transport pipe, the compressed air is not reduced, and the aggregate being transported can be prevented from being clogged in the transport pipe. In addition, since the flow velocity of the spray material does not increase unnecessarily, while obtaining a certain amount of rectification effect of the spray material, the silt component separated from the spray material in the transport pipe immediately before spraying is separated as it is, It can discharge | emit from the front-end | tip of a nozzle part, and construction using high quality mortar or concrete can be performed.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is an explanatory view schematically showing a configuration of a mortar or concrete spraying device (hereinafter referred to as spraying device) D according to an embodiment of the present invention.
The spraying device D is an aggregate pumping machine 2 as an aggregate supply means for supplying aggregate (sand (fine aggregate) in the case of mortar M, sand and crushed stone (coarse aggregate) in the case of concrete) 1. And an air compressor 3 as compressed air supply means connected to the aggregate pump 2 and a pump for feeding as cement milk sending means for sending cement milk 6 mixed with cement 4 and water 5 (for example, , Piston type pump, squeeze type pump) 7 and a downstream part of the aggregate pump 2 and a cement milk introduction part 9 for mixing the mortar M (or concrete) is provided in the middle part thereof. A cement pipe having an upstream end connected to the downstream side of the conveying pipe 8 and the pump 7 for pumping, and a downstream end connected to the downstream part of the transport pipe 8 via the cement milk introduction part 9. And a milk delivery pipe 10.

The spraying device D is of a separate pressure-feeding type in which the aggregate 1 and the cement milk 6 are separately pumped, and both 1, 6 are mixed just before spraying from the downstream portion of the transport pipe 8. .

The aggregate pump 2 discharges the aggregate 1 to the downstream side with compressed air (also referred to as compressed air or high-pressure air) supplied from the air compressor 3, and is discharged as described above. The aggregate 1 is led into the transport pipe 8 and sent to the downstream side of the transport pipe 8 by the high-pressure air.

FIG. 2 is an explanatory diagram schematically showing the configuration of the aggregate pumping machine 2.
The aggregate pumping machine 2 includes a hook 11 having an upper hook 11a and a lower hook 11b for containing aggregate, a state in which the inside of the upper hook 11a communicates with the outside by opening and closing, and a state in which the inside is isolated from the outside. A first opening / closing means (for example, an opening / closing plate) 12 to be switched to, a second opening / closing means (for example, an opening / closing plate) 13 for opening / closing between the upper hook 11a and the lower hook 11b, and a lower part of the hook 11 (lower pot 11b). It is provided in a state where it communicates with the inside of the hook 11 (lower hook 11b) through the communication port 14 on the side, and is provided with a delivery section 15 to which the transport pipe 8 is connected.

Compressed air from the air compressor 3 is introduced into the upper hook 11a so that the upper hook 11
a pressurizing pipe 16 as a compressed air flow passage for pressurizing the inside of a, and an air vent pipe 17 for deriving and depressurizing the air in the upper hook 11a to the outside, and the upper pot 11
In the upper part of a, there is a loading hopper 18 for loading the aggregate 1 and the first opening / closing means 12.
And are provided. Furthermore, the stirring blade 19 for stirring the accommodated aggregate 1 is provided inside the upper hook 11a.

The upstream end of the pressurizing pipe 16 is connected to the air compressor 3, and in the middle, the compressed air from the air compressor 3 is supplied to the downstream upper hook 11a and is not supplied. Switching means (for example, a switching valve) 16a for switching is provided.

The air vent pipe 17 has switching means (for example, a switching valve) 17a for switching between a state in which the air in the upper hook 11a is led out and a state in which the air is not led out.

FIG. 3 is an exploded perspective view schematically showing the configuration of the stirring blade 19.
The stirring blade 19 includes a rotating shaft body 20 that rotates about its axis, and two blades 21 and 21 that are fixed to the rotating shaft body 20.

The blade 21 includes a fixed portion 22 having a substantially U-shaped cross section fixed to the rotary shaft body 20, two arm portions 23 and 23 connected to the fixed portion 22, and arm portions 23 and 23.
And an arcuate portion 24 provided at the tip.

The arc-shaped portion 24 is a first arc portion 2 connected to the tips of the arm portions 23, 23.
4a, a second arc portion 24b having substantially the same shape as the first arc portion 24a, a size larger than the first arc portion 24a and the second arc portion 24b, and the first arc portion 24a and And a third arc portion 24c sandwiched by the second arc portion 24b. And the said 3rd circular arc part 24c which will contact | abut directly to the inner wall of the said upper hook 11a is formed from the material with some elasticity, such as rubber | gum.

The fixed portion 22 is fixed to the rotary shaft 20 and the three arc portions 24a.
24b, 24c can be fixed using, for example, a bolt 34b and a nut 34c that are screwed together via a C ring 34a.

Compressed air from the air compressor 3 is introduced into the lower pot 11b so that the lower pot 11
A pressurizing pipe 25 as a compressed air flow passage for pressurizing the inside of b is connected to an air vent pipe 26 for leading the air in the lower pot 11b to the outside and reducing the pressure, and the lower pot 11
The upper hook 11a is connected to the upper part of b through a second on-off valve 13. Furthermore, the stirring blade 27 for stirring the accommodated aggregate 1 is provided in the lower hook 11b.

The upstream end of the pressurizing pipe 25 is connected to the air compressor 3, and in the middle, the state is switched between a state where compressed air from the air compressor 3 is supplied into the downstream lower hook 11b and a state where it is not supplied. Switching means (for example, a switching valve) 25a and a check valve (not shown) are provided.

The air vent pipe 26 has switching means (for example, a switching valve) 26a for switching between the state in which the air in the lower hook 11b is led out and the state in which it is not led out.

FIG. 4 is an exploded perspective view schematically showing the configuration of the stirring blade 27.
The stirring blade 27 includes a rotating shaft body 28 that rotates about its axis, and two blades 29 and 29 fixed to the rotating shaft body 28.

The rotary shaft body 28 has arm portions 30 and 31 connected to both ends, and the arm portion 30 provided at one end and the arm portion 31 provided at the other end include the rotary shaft 28. It is arranged so as to be on the opposite side across. In addition, two arm portions 32 and 33 are connected to the central portion of the rotating shaft body 28 so as to be opposite to each other with the rotating shaft body 28 interposed therebetween. One blade 29 is fixed in a curved state from the arm portion 30 to the arm portion 32, and the other blade 29 is fixed in a curved state from the arm portion 33 to the arm portion 31.

The blades 29 are respectively provided with the arm portions 30 and 32 (or arm portions 33 and 31).
A first curved portion 29a connected to the tip of the first curved portion, a second curved portion 29b having substantially the same shape as the first curved portion 29a, and a size slightly larger than the first curved portion 29a and the second curved portion 29b. And a third curved portion 29c sandwiched between the first curved portion 29a and the second curved portion 29b. The third curved portion 29c that comes into direct contact with the inner wall of the lower hook 11b is formed of a material having a certain degree of elasticity such as rubber.

The three curved portions 29a, 29b, and 29c are fixed by, for example, a washer 34a.
It can be performed using a bolt 34b and a nut 34c screwed together.

Further, a closing body 35 is disposed below the bottom wall of the hook 11 (lower hook 11b) so as to close a part of the communication port 14. The closing body 35 has a circular through hole 35 at the center.
a is a plate-like member provided with a channel area (inner cross-sectional area) or less, more specifically, about 1/4 to the channel area (inner cross-sectional area) to about the channel area (inner cross-sectional area). It is for configuring.

For example, when the cross section of the flow path formed in the transport pipe 8 is circular and the inner diameter is 42 mm, the communication port 14 is circular and the diameter is 69 mm. The diameter of the through hole 35a of the closing body 35 can be 24 mm.

A pressure pipe 36 that sends compressed air from the air compressor 3 is connected to the delivery section 15 or the upstream end of the transport pipe 8 connected to the delivery section 15.

  The aggregate pumping machine 2 is placed on the movable carriage 37.

Furthermore, the aggregate pumping machine 2 measures the pressure inside the upper hook 11a and the lower hook 11b,
It has pressure gauges 38 for displaying.

Next, operation | movement of the aggregate pumping machine 2 which consists of said structure is demonstrated.
(1) First, the first opening / closing means 12 is opened, and the aggregate 1 is charged from the charging hopper 18 into the upper hook 11a. At this time, the second opening / closing means 13 is closed, and the aggregate 1 is housed in the lower hook 11b. As described above, the aggregate 1 put into the upper hook 11 a is stirred by the stirring blade 19.

(2) Then, the first opening / closing means 12 is closed, and the aggregate 1 in the lower hook 11b is moved to the delivery portion 15.
(3) The switching means 17a provided in the air vent pipe 17 is closed, and the switching means 16a provided in the pressure pipe 16 is closed. , The compressed air from the air compressor 3 can be
It introduce | transduces in a, and pressurizes the inside of the upper hook 11a.

After that, if the pressure in the upper hook 11a becomes substantially equal to the pressure in the lower hook 11b which has been pre-pressed, (4) the switching means 16a is closed, and the air compressor 3 into the upper hook 11a.
The introduction of the compressed air from the stop is stopped, the second opening / closing means 13 is opened, and the aggregate 1 in the upper hook 11a is opened.
Is put into the lower pot 11b.

Then, when the introduction of the aggregate 1 from the upper hook 11a to the lower hook 11b is completed, (5) the second
The opening / closing means 13 is closed, the switching means 17a of the air vent pipe 17 is opened, and the upper hook 11
The air in a is led out to the outside, and the pressure in the upper hook 11a is returned to a state equal to the external pressure,
Thereby, it will be in the state which can throw in the aggregate 1 again from the said charging hopper 18 in the upper hook 11a.

After the above operation, the operation returns to the operation (1) again. In the aggregate pumping machine 2, the aggregate 1 is continuously conveyed by repeating the operations (1) to (5). It has become.

On the other hand, in the lower pot 11b into which the aggregate 1 has been introduced from the upper pot 11a, the aggregate 1 is being stirred by the stirring blade 27, and from the communication port 14 provided on the bottom wall of the lower pot 11b, the delivery unit 1 is provided.
Aggregate 1 is dropped on 5. Then, the aggregate 1 dropped on the delivery unit 15 is delivered into the transport pipe 8 and sent downstream thereof.

In the aggregate pumping machine 2 having the above-described configuration, the aggregate 1 in the lower hook 11 b guided to the outlet 14 by the stirring blade 27 is input from the communication port 14 to the lower delivery unit 15. However, the closing body 35 is disposed below the communication port 14, and the opening area of the communication port 14 is equal to or smaller than the flow channel area (inner cross-sectional area) in the transport pipe 8. Since it is configured to be about 1/4 of the inner cross-sectional area) to about the channel area (inner cross-sectional area), the aggregate 1 in an amount less than the limit of the conveying force of the conveying tube 8 is sent from the lower pot 11b. A large amount of aggregate 1 exceeding the limit of the conveying force of the conveying tube 8 flows into the conveying tube 8 at a time, and the clogging in the conveying tube 8, It is possible to reliably prevent the occurrence of pulsation.

Further, in the aggregate pumping machine 2, a closing body 35 that closes a part of the communication port 14 is disposed below the communication port 14, whereby a pool portion where the aggregate 1 is accumulated above the closing body 35. Therefore, the introduction of the aggregate 1 in the lower hook 11b into the communication port 14 is not intermittent with the rotation of the stirring blade 27, and the communication of the aggregate 1 by the stirring blade 27 is not performed. Since the aggregate 1 accumulated in the accumulation portion continues to flow to the delivery section 15 even when the introduction to the mouth 14 is not performed, the continuity of conveyance of the aggregate 1 can be improved, and the conveyance tube This is very effective in preventing clogging of the inside 8 and pulsation of the aggregate 1.

Here, as shown in FIG. 5 (A), in the case where the obstruction body 35 is inclined such that the portion closer to the through hole 35a is located on the lower side, The accumulated aggregate 1 is likely to drop to the lower delivery section 15, and the continuity of transport of the aggregate 1 is further improved.

Moreover, in the aggregate pumping machine 2 which consists of said structure, since the non-return valve is provided in the said pressurization pipe 25, the following effects are acquired. That is, since it is the single air compressor 3 that applies pressure to the upper hook 11a, the lower hook 11b, and the conveying pipe 8 (sends compressed air), the pressure applied to the upper hook 11a (or to the upper hook 11a). Compressed air flow rate) A, lower pot 1
If the pressure applied to 1b (or the compressed air flow rate sent to the lower pot 11b) is B, and the pressure applied to the transport tube 8 or the delivery unit 15 (or the compressed air flow rate sent to the delivery tube 8 or the delivery unit 15) is C, the air compressor The total pressure applied by 3 (the total flow of compressed air) is A +
B + C. Here, it is preferable that each air is equipped with an air chamber (not shown) in the aggregate pressure feeder 2 and supplied through the air chamber.

In the operation (3), when the compressed air starts to be sent from the air compressor 3 to the upper hook 11a in order to increase the pressure in the upper hook 11a, the pressurized pipe 25 and the upper hook 11a connected to the lower hook 11b. When the check valve is not provided in the pressurizing pipe 25, the pressure B in the lower hook 11b is higher than the pressure A in the upper hook 11a. Therefore, the compressed air in the lower hook 11b flows into the upper hook 11a through the pressure pipes 25 and 16, and a pressure drop occurs in the lower hook 11b, which decreases the discharge amount of the aggregate 1 carried out from the lower hook 11b. This leads to a decrease in the conveying force of the aggregate 1 and variations in the quality of the formed mortar or concrete. However, as described above, the check valve is provided in the pressure pipe 25 connected to the lower hook 11b so as to suppress the fluctuation of the pressure (flow rate) of the compressed air sent from the air compressor 3 to the lower hook 11b. Therefore, it is possible to prevent the compressed air in the lower hook 11b from flowing to the upper hook 11a, thereby maintaining a large conveying force of the aggregate 1 and enabling stable continuous conveyance. Also with such a configuration, it is possible to prevent clogging or pulsation in the transport pipe 8, and it is also possible to prevent variations in the quality of the formed mortar or concrete.

In order to achieve more uniform conveyance of the aggregate 1, it is preferable to reduce the opening area (total opening area) of the communication port 14 as much as possible and increase the number of blades 29 of the stirring blade 27.

Further, in the aggregate pumping machine 2, since the opening area of the communication port 14 is larger than the flow path area (inner cross-sectional area) in the transport pipe 8, the blocking body 35 is used to reduce the opening area. However, it is not limited to such a configuration, the communication port 14 itself is made small,
The opening area is configured to be equal to or less than the flow path area (inner cross-sectional area) in the transport pipe 8, more specifically, about 1/4 of the flow path area (inner cross-sectional area) to the flow area (inner cross-sectional area). May be.

Further, the number of the communication ports 14 is not limited to one and may be plural. In this case, the total area of the openings of the communication ports 14, 14... Is less than or equal to the flow path area (inner cross-sectional area) in the transport pipe 8. What is necessary is just to comprise so that it may become a road area (inner cross-sectional area) grade, and when the said total area is too large, what is necessary is just to obstruct | occlude a part of some communication port 14,14 ... by the said obstruction | occlusion body 35. .

Further, the closing body 35 is not limited to the plate-like member provided with the circular through-hole 35a at the center as described above, for example, a normal plate-like member not having the through-hole 35a. The closing body 35 may be configured by the following, and the closing body 35 may be disposed so as to close a part of the communication port 14 as shown in FIG. Of course, you may make it obstruct | occlude a part of the said communication port 14 using two or more obstruction bodies 35 which have the above structures.

The transport pipe 8 includes, for example, a connection hose portion 8a formed by connecting a plurality of flexible hoses of about 20 m, and the cement milk introduction portion 9 provided on the downstream side of the connection hose portion 8a. A nozzle part 39 is provided on the downstream side of the cement milk introduction part 9 and discharges the aggregate 1 and the cement milk 6 mixed in the cement milk introduction part 9.

In addition, as the said conveyance pipe | tube 8, it is possible to use the hose for normal mortar or concrete spraying, for example. Moreover, in the said conveyance pipe | tube 8, the distance from the cement milk introduction | transduction part 9 to the nozzle part 39 is the length required in order that the aggregate 1 and the cement milk 6 may be fully mixed, for example, 1-20 m (Preferably about 3 to 10 m).

The connecting hose portion 8a is configured to have a length of, for example, about 100 m, but can be 700 m at a horizontal distance on flat ground, 200 m at a straight height on a slope, and about 400 m at a horizontal distance.

And it is comprised so that the internal diameter of the downstream part from the said cement milk introduction | transduction part 9 of the said conveyance pipe | tube 8 (connection hose part 8a) may become larger than the internal diameter of the upstream part (FIG. 6 (A).
)reference). For example, the inner diameter of the upstream portion of the transport pipe 8 (connection hose portion 8a) is 42 mm.
The inner diameter of the downstream portion may be 50 mm, the inner diameter of the upstream portion of the transport pipe 8 (connection hose portion 8a) may be 38 mm, and the inner diameter of the downstream portion may be 42 mm.

The cement milk delivery pipe 10 is formed to have an inner diameter of about 1 to 3 cm, for example, and the downstream portion is divided into two forks. In addition, this downstream part does not necessarily need to be divided into two forks, and when there is a concern about hardening of the cement milk (mortar milk) 6 (for example, when working in a high temperature / high temperature environment), the cement milk delivery pipe 19 In some cases, it is preferable not to divide the downstream part into two parts.

6A and 6B are a longitudinal sectional view and an explanatory view schematically showing a configuration of the cement milk introducing portion 9.
The cement milk introduction part 9 is for mixing the cement milk 6 that has flowed in the cement milk delivery pipe 10 with the aggregate 1 that flows in the transport pipe 8, and is in the middle of the connecting hose part 8a. It is arranged in a state of interrupting, and has a substantially cylindrical shape. In addition, the said cement milk introducing | transducing part 9 is formed from metals, such as aluminum, for example.

Specifically, the cement milk introduction portion 9 is formed with a tapered portion 9a having an inner diameter that increases toward the downstream side. In addition, as shown to FIG. 6 (A), the cement milk introduction | transduction part 9 in a present Example is formed as the taper-shaped part 9a from which the whole becomes large toward the downstream.

Further, as shown in FIG. 6 (A), the direction in which the aggregate 1 flows and the direction in which the cement milk 6 flows with respect to the tapered portion 9a of the cement milk introduction portion 9 is acute (for example, 10). The downstream portions of the cement milk delivery pipe 10 are connected so as to be -40 degrees, preferably 15-30 degrees. Further, as shown in FIG.
Each downstream portion of the cement milk delivery pipe 10 is connected at an angle to the tapered portion 9a so that the cement milk 6 flowing into the conveyance pipe 8 draws a spiral along the inner wall of the conveyance pipe 8. It is like that.

Here, in the cement milk introduction part 9, the mortar M (or concrete) is formed by mixing the cement milk 6 and the aggregate 1. The mortar M includes cement 4, aggregate (sand). 1, water 5 and an appropriate admixture are used, for example, cement 4: aggregate (sand) 1: water 5 = 1: 4: 0.45 to 0.6. In the case of concrete, a part of the sand is appropriately replaced with crushed stone.

The cement milk introduction part 9 is not limited to the tapered part 9a whose entire inner diameter is increased toward the downstream side, and has the tapered part 9a in part. May be. For example, as shown in FIG. 7, you may have the said taper-shaped part 9a and the reverse taper-shaped part 9b from which an internal diameter becomes small toward a downstream in order from the upstream.

Further, it is preferable to line the inner surface of the cement milk introduction portion 9 with wear-resistant rubber or synthetic resin in order to reduce wear caused by the aggregate 1.

FIG. 8 is an explanatory diagram schematically showing the configuration of the nozzle portion 39.
The nozzle portion 39 has a widened portion 3 in which the inner diameter increases from the upstream side toward the downstream side.
9a and a throttle portion 39b whose inner diameter decreases toward the downstream side.
Is configured to be equal to or slightly larger than the inner diameter of the transport pipe 8. As a result, the silt content 40 separated during the conveyance of the mixture of the aggregate 1 and the cement milk 6 that is the material of the mortar M becomes difficult to be mixed with the mixture again in the nozzle portion 39, and the separated silt content 40 is The effect of falling and separating from the discharge port of the nozzle portion 39 is obtained.

Next, a method for placing mortar concrete performed using the spraying device D having the above-described configuration will be described.
The mortar concrete placing method is carried out by driving the aggregate pumping machine 2 and the air compressor 3 and the pumping pump 7 and moving the nozzle portion 39 of the transport pipe 8 to an appropriate position. it can.

That is, by driving the aggregate pumping machine 2 and the air compressor 3, the aggregate 1 is fed into the transport pipe 8 together with the high-pressure air and reaches the cement milk introduction part 9.

On the other hand, by driving the pump 7 for pumping, the cement milk 6 is fed into the cement milk delivery pipe 10 and reaches the cement milk introduction part 9.

Then, the cement milk 6 and the aggregate 1 are mixed with each other, and further from the cement milk introduction portion 9 to the downstream side. Finally, each grain of the aggregate 1 is firmly coated with the cement milk 6. Thus, the aggregate 1 and the cement milk 6 are uniformly mixed without any unevenness.

As described above, the cement milk 6 and the aggregate 1 are mixed at an appropriate ratio, whereby the mortar M (or concrete) is formed, and the formed mortar M (or concrete) is used as the cement milk introduction portion. 9 is discharged from the nozzle portion 39 on the downstream side to the mortar (or concrete) placement position.

According to the spraying device D having the above-described configuration, it is possible to perform mortar or concrete spraying smoothly and reliably even for long-distance conveyance.

That is, in the spraying apparatus D, in the aggregate pumping machine 2 for pumping the aggregate 1, the closing body 35 is disposed below the communication port 14, and the opening area of the communication port 14 is set to be the transport pipe. Since the flow path area (inner cross-sectional area) in FIG. 8 is less than or equal to, specifically, 1/4 of the flow area (inner cross-sectional area) to the flow area (inner cross-sectional area), An amount of the aggregate 1 below the limit of the transport force of the transport tube 8 can be made to flow from the lower hook 11b to the delivery unit 15 in a fixed amount, and a large amount of bone exceeding the limit of the transport force of the transport tube 8 as in the prior art. The material 1 flows into the transport pipe 8 at a time, and the transport pipe 8
It is possible to reliably prevent internal clogging and pulsation.

In addition, a closing body 35 that closes a part of the communication port 14 is disposed below the communication port 14, thereby forming a reservoir portion in which the aggregate 1 is accumulated above the closing body 35. The introduction of the aggregate 1 in the lower hook 11b into the communication port 14 does not become intermittent as the stirring blade 27 rotates, and the stirring blade 27 introduces the aggregate 1 into the communication port 14. Since the aggregate 1 accumulated in the accumulation portion continues to flow to the delivery section 15 even when it is not broken, the continuity of conveyance of the aggregate 1 can be improved, and the clogging and aggregate in the conveyance tube 8 can be improved. This is very effective in preventing the pulsation of 1.

Further, since the pressure pipe 25 is provided with a check valve, when the compressed air starts to be sent from the air compressor 3 to the upper hook 11a in order to increase the pressure in the upper hook 11a, the upper hook 11
It is possible to prevent the compressed air in the lower hook 11b having a pressure higher than that in a from flowing into the upper hook 11a, thereby maintaining a large conveying force of the aggregate 1 and enabling stable continuous conveyance. In addition, even with such a configuration, clogging and pulsation can be prevented from occurring in the transport pipe 8, and variations in the quality of the formed mortar or concrete can also be prevented.

Moreover, since the internal diameter of the downstream part of the said conveyance pipe | tube 8 (connection hose part 8a) from the said cement milk introduction part 9 is comprised larger than the internal diameter of the upstream part, it is as follows. Effects can be obtained.

That is, in the conventional spraying apparatus in which the inner diameter of the downstream portion of the transport pipe 8 from the cement milk introduction portion 9 is equal to the inner diameter of the upstream portion, Immediately after the cement milk 6 is introduced into the aggregate 1 as the conveyed product flowing in the inside 8, the conveyed item flowing in the conveying pipe 8 becomes a mixture of the aggregate 1 and the cement milk 6, and accordingly, the conveyed item Since the volume and weight of the transported material increase, the transport speed of the transported material on the downstream side of the cement milk introducing unit 9 decreases, and due to the effect of the stagnation of transport of the transported product, the cement milk introducing unit 9 in the transport pipe 8 Even on the upstream side, the conveyance speed of the conveyed product (aggregate 1) is reduced, and a blockage may occur as the conveyance speed decreases.

Further, when the amount of the conveyed product with respect to the conveying pipe 8 becomes too large due to the introduction of the cement milk 6, the aggregate 1 and the air from the air compressor 3 for flowing the cement milk 6 to the downstream side are increased. The passage of the compressed air is lost, and the inside of the transport pipe 8 is blocked by the transported material (that is, the aggregate 1 and the cement milk 6).

However, in the spraying device D having the above-described configuration, the passage of the compressed air from the air compressor 3 can be routed by increasing the inner diameter of the downstream portion of the transport pipe 8 from the cement milk introduction portion 9. In addition, since the decrease in the transport speed of the transported material passing through the transport pipe 8 can be suppressed, the transport pipe 8 is reliably prevented from being blocked by the aggregate 1 and the cement milk 6. It is possible to perform a smooth spraying construction.

Further, the cement milk introduction portion 9 has a tapered portion 9a whose inner diameter increases toward the downstream side.
The downstream portions of the cement milk delivery pipe 10 are connected to the tapered portion 9a so that the flow direction of the aggregate 1 and the flow direction of the cement milk 6 are acute in the longitudinal section. Further, each downstream portion of the cement milk delivery pipe 10 is inclined with respect to the tapered portion 9a so that the cement milk 6 flowing into the transport pipe 8 spirals along the inner wall of the transport pipe 8. The following effects can be obtained from the connection.

That is, the cemented milk introduction part 9 in the conveying pipe 8 is not formed with a tapered portion 9a having a larger inner diameter toward the downstream side, and the cement milk introduction part is formed in a cylindrical shape having the same diameter from the upstream side to the downstream side. In the conventional spraying device, since the aggregate transported in the transport pipe was easy to hit against the cement milk introducing section that is cylindrical rather than tapered, the cement milk introducing section was heavily worn, It was difficult to realize long-time continuous conveyance.

Further, in the conventional spraying device, the cement milk discharged to the cement milk introduction section has a curtain shape, and the cement milk curtain becomes the resistance of the compressed air flowing in the transport pipe to transport the aggregate. As a result, the conveyance force of the compressed air may be reduced, causing a blockage in the conveyance pipe.

Therefore, in order to prevent the cement milk introduced into the cement milk introduction part from becoming a curtain shape, the cement milk delivery pipe is connected to the cement milk introduction part at an acute angle, and the cement milk with respect to the conveying direction of the aggregate. It is conceivable that the cement milk is introduced along the inner wall of the cement milk introduction part by reducing the angle formed by the introduction direction, but in this case, the cement milk introduction part is not tapered but cylindrical. As a result, the area of the opening for introducing cement milk from the cement milk delivery pipe formed in the cement milk introduction section becomes large, and the compressed air flowing in the transport pipe can easily enter from this opening. There was a risk of hindering the introduction of cement milk.

However, in the spraying device D having the above-described configuration, a tapered portion 9a having a larger inner diameter is formed on the downstream side, and the cement milk delivery pipe 10 is connected to the tapered portion 9a. Therefore, the aggregate 1 transported in the transport pipe 8 becomes difficult to directly hit,
The wear of the cement milk introduction part 9 is reduced, and it becomes possible to realize continuous conveyance for a long time.

Moreover, in the spraying apparatus D which has said structure, the taper-shaped part 9a whose internal diameter becomes large is formed in the downstream, and the flow direction of the aggregate 1 and the flow direction of the cement milk 6 with respect to this taper-shaped part 9a. Are connected to each downstream portion of the cement milk delivery pipe 10 so that the vertical section has an acute angle, and the cement milk 6 flowing into the transport pipe 8 draws a spiral along the inner wall of the transport pipe 8. As described above, since each downstream portion of the cement milk delivery pipe 10 is connected to the tapered portion 9a at an angle, the cement milk 6 follows the inner wall of the cement milk introduction portion 9. The air does not become a curtain and does not become the resistance of the compressed air flowing through the conveying pipe 8 to convey the aggregate 1. Reducing the force, thereby preventing that cause blockage in the conveying pipe.

The cement milk delivery pipe 10 is connected to the cement milk introduction part 9 at an acute angle, and the angle formed by the introduction direction of the cement milk 6 with respect to the conveying direction of the aggregate 1 is reduced. Since the portion to which the delivery pipe 10 is connected is a tapered portion 9a, an opening for introducing the cement milk 6 from the cement milk delivery tube 10 formed in the cement milk introduction portion 9 (tapered portion 9a). Can be made smaller than before, so that the compressed air flowing in the conveying pipe 8 can be prevented from entering from the opening, and the cement milk 6 can be introduced smoothly.

Further, the nozzle portion 39 is provided with a widened portion 39a whose inner diameter increases toward the downstream side and a throttle portion 39b whose inner diameter decreases toward the downstream side in order from the upstream side, and the inner diameter of the downstream end of the throttle portion 39b. However, since it is configured to be equal to or slightly larger than the inner diameter of the transfer tube 8, the following effects can be obtained.

That is, in the conventional spraying device in which the diameter of the tip of the nozzle portion 39 is narrowed to be smaller than the inner diameter of the transport pipe 8, the throttle of the tip of the nozzle section 39 has been transported through the transport pipe 8. The sprayed material (aggregate 1 and cement milk 6) becomes a resistance, and the compressed air is depressurized, and the aggregate 1 being conveyed may be clogged in the conveyance tube 8. Further, the silt portion 40 that has been separated from the spray material in the transport pipe 8 immediately before spraying is mixed with the spray material again, making it difficult to construct using high-quality mortar or concrete.

However, in the spraying device D having the above-described configuration, the diameter of the tip portion of the nozzle portion 39 is narrowed so as to be the same as or slightly larger than the inner diameter of the transport tube 8, It does not become the resistance of the spray material (the aggregate 1 and the cement milk 6) that has been transported, and the compressed air is not reduced, and the transported aggregate 1 can be prevented from being clogged in the transport pipe 8. Further, since the flow velocity of the spray material does not increase unnecessarily, it is separated from the spray material in the transport pipe 8 immediately before spraying, as shown in FIG. The silt portion 40 can be discharged from the tip of the nozzle portion 39 in a state where it is separated as it is, and it is possible to perform construction using high quality mortar or concrete.

By using the spraying device D having the above-described configuration, it is possible to achieve high quality even in places where it is difficult or impossible to carry out conventional construction, such as places where it is difficult to bring a machine near the top of a steep mountain. It can be protected with mortar or concrete.

And, for example, when you want to protect the landscape by greening on slopes (slopes) that may collapse, form a grid-like frame by spraying mortar or concrete using the spraying device D In addition, a method of spraying a vegetation base material into the legal frame to protect the greening of the slope can be adopted. Hereinafter, specific examples of such a method will be described.

FIG. 9 is an explanatory view schematically showing a configuration of an example of a spray method frame method using the spray device D. As shown in FIG.
In the spray frame method of this embodiment, first, as a first step (mesh body installation step), a net body 41 such as a rhombus or a turtle shell is placed on the slope N targeted for greening protection, In addition, the auxiliary anchor 42 is driven into the slope N at an appropriate interval, and the mesh body 41 is fixed to the slope N. In addition, the said net-like body 41 is comprised with the strand about 0.8-1.6 mm in diameter, for example, and the scale is about 2-6 cm.

Subsequently, as a second step (frame body installation step), a plurality of wire rods 43 made of reinforcing bars (others may be, for example, a wire rope) are placed on the mesh body 41 at least in the vertical direction (perpendicular to the contour line of the slope N). ) Or the horizontal direction (direction parallel to the contour line of the slope N), and preferably arranged in a lattice shape, and the frame 44 for forming the normal frame is formed in the longitudinal direction of the wire 43. The wire rod 43 is lifted up and held by the frame body 44.

Here, the frame body 44 for forming the method frame can hold the wire 43, for example, the height is about 15 to 20 cm, the width is about 30 to 35 cm, and the length is 30 to 60 cm. It consists of a combined structure of wire by welding. Specifically, as shown in FIG. 10, a pair of semicircular frame members 45, two connecting members 46 that integrate the pair of frame members 45, and a wire rod extending between the two connecting members 46. And holding member 47.

Therefore, after installing the frame 44 so as to straddle the wire 43, the wire 43 is attached to the wire holding member 47.
The wire 43 is held at a predetermined height position on the slope N by lifting it to the side and binding it to the wire holding member 47 with the wire b or the like.

Next, as a third step, the curing sheet 48 is arranged on the mesh body 41 of this part so that the part surrounded by the wire rods 43 arranged in a lattice shape becomes a vegetation area. Thereafter, as the fourth step (spraying step), using the spraying device D, the mortar M or concrete is used, the frame body 44 for forming the legal frame is used as a guide for the spray width and the spray height, and the lattice is used. On the slope N, a grid-like frame 49 is formed by raising the mortar M or concrete.

Finally, as a fifth step, the curing sheet 48 is removed after the predetermined curing of the mortar M or concrete, and the vegetation substrate 50 is landed in the vegetation area.

With the spray frame method constructed as described above, the slope N where mortar or concrete spraying was extremely difficult or impossible with conventional spraying equipment, such as near the top of a steep mountain.
The mortar M or concrete is sprayed onto the frame 49 to form the frame 49.
Therefore, after the formation of the law frame 49, the preservation of the landscape by the plant and the restoration of the slope N to the natural state can be achieved at an early stage.

Further, for example, when there is a rock that may collapse on the top of a steep slope and it is dangerous to remove the rock itself, the above-mentioned spraying device D is used to prevent the rock from collapsing. A method of joining the rock mass by transporting the mortar M and filling the cracked portion of the rock mass can be adopted. Hereinafter, specific examples of such a method will be described.

FIGS. 11A to 11C are explanatory views schematically showing a configuration of an example of a bedrock bonding method using the spraying device D. FIG.
In the bedrock bonding method of this embodiment, as a first step, when there is a risk of collapse of the entire bedrock G, the mortar M or the like is filled and stabilized at the base using the spraying device D.

Subsequently, as shown in FIG. 11A, as a second step (cleaning step), air or water is blown at a high pressure to clean the bonding surface (the surface to be bonded by mortar M or the like). . Thereby, earth and sand, moss and the like present on the bonding surface are removed.

Next, as shown in FIG. 11 (B), as a third step (a stuffing step), a stuffing material 52 is stuffed as appropriate, for example, in the vicinity of the opening 51 of the bedrock G / rock block fissure 51. This process is performed in the next process (
This is to form a dam that prevents the mortar M and the like in the fourth step) from flowing out from the crack portion 51, and the interstitial material 52 has a good adhesion to the mortar M and the like. It may be used. It is desirable from the viewpoint of economy and adhesion to perform the clogging using the same material, such as mortar M. In the next step (fourth step), this third step can be omitted if there is no risk of the mortar M or the like flowing out from the crack portion 51.

Finally, as shown in FIG. 11C, as the fourth step (injection step), the spraying device D
The mortar M or concrete is poured into the crack 52 using Since the mortar M or concrete used in this step needs to be filled up to the crack details, the blending is appropriately adjusted to improve the fluidity.

With the rock mass bonding method constructed as described above, it is impossible to transport mortar or concrete with conventional spraying equipment, such as near the top of a steep mountainous area, or to install the spraying equipment on an unstable mountainside. The mortar M or concrete can be transported over a long distance using the above-mentioned spraying device D to the huge rock, rock mass G, or rock block that exists on the required slope N and has the risk of falling rocks. The whole slope N can be stabilized by adhering and filling the rock 52 and the crack 52 of the rock mass with mortar M or concrete.

Further, the spraying device D according to the present invention is a retaining wall construction in a mountainous area, for example, JP-A-6-2.
It can also be applied to the retaining wall construction method disclosed in Japanese Patent No. 94139. In the case of the retaining wall method, basically, mortar M or concrete is placed between the cut or embankment slope and the molding plate (formwork) of the retaining wall that is erected with a gap from the slope. Build a retaining wall.
In this case, the mortar M can be used without lifting and transporting the spray device D to the vicinity of the retaining wall construction site.
Alternatively, the concrete material can be placed for a long distance, and a high-quality retaining wall can be constructed.

The spraying device D according to the present invention can also be applied to construction works for dams and dams for the purpose of sand control in mountainous areas, for example, a construction method described in Japanese Patent Laid-Open No. 10-266168. In the case of a construction method for a weir or dam, basically, mortar M or concrete is placed between shaped plates (form frame: sandbag in the case of the above-mentioned gazette) standing on the front and back surfaces of the weir body. By constructing a weir body.
In this case, the mortar M can be used without lifting and transporting the spraying device D to the vicinity of the weir body construction site.
Alternatively, the concrete material can be transported for a long distance and can be placed, and a high-quality weir body can be constructed.

FIG. 12 is an explanatory view schematically showing a configuration of an example of tunnel formation work using the spraying device D.
The spraying device according to the present invention exhibits its superiority in such tunnel formation work. Specifically, the main process of tunnel construction is
(1) Excavating natural ground 53 and transporting the excavated earth and sand outside the tunnel (hereinafter referred to as process 1)
(2) Step of spraying concrete 54 onto natural ground excavation surface 55 (hereinafter referred to as step 2)
(3) A step of driving the rock bolt 56 in the natural ground 53 so as to have a radial shape in a cross-sectional view of the tunnel (hereinafter referred to as step 3).
(4) A step of waterproofing such as attaching a waterproof sheet (not shown) to the concrete surface 54 formed in Step 2 (hereinafter referred to as Step 4).
(5) Step of driving concrete 57 using a tunnel formwork (centre) (hereinafter,
Called process 5)
Can be divided into

Step 1 is an excavator, Steps 2 and 3 are supporters (steps to support and keep the excavated grounds not to collapse), and Steps 4 and 5 are linings (steps to cover and reinforce the supporters). In tunnel formation work, tunnels are formed by sequentially repeating these steps.

Here, concrete 54 and 57 will be used in steps 2 and 5, but since the concrete has been sprayed after transporting the concrete to the construction site with a mixer truck, it is not completely self-supporting yet and is a narrow tunnel. Inside, the operation of the mixer truck is difficult and dangerous,
The workability was reduced due to the time required for transportation. However, by using the spraying device D of the present invention capable of transporting concrete over a long distance, a plant can be installed outside the tunnel that is safe and wide in work space, and at the same time, a rubber hose that is easy to handle is constructed from the plant. As long as it is extended to the location, conventional spraying is possible and high-quality concrete spraying is possible, which can contribute to the improvement of the safety and workability of tunnel formation work.

It is explanatory drawing which shows roughly the structure of the mortar or concrete spraying apparatus which concerns on one Example of this invention. It is explanatory drawing which shows roughly the structure of the aggregate pumping machine in the said Example. It is a disassembled perspective view which shows schematically the structure of the stirring blade of the upper hook in the said Example. It is a disassembled perspective view which shows schematically the structure of the stirring blade of the lower hook in the said Example. (A) And (B) is explanatory drawing which shows schematically the structure of the modification of the obstruction | occlusion body in the said Example, and the further modification. (A) And (B) is the longitudinal cross-sectional view and explanatory drawing which show schematically the structure of the cement milk introduction | transduction part in the said Example. It is explanatory drawing which shows schematically the structure of the modification of the said cement milk introduction part. It is explanatory drawing which shows schematically the structure of the nozzle part in the said Example. It is explanatory drawing which shows roughly the structure of the spraying method frame construction method using the said spraying apparatus. It is explanatory drawing which shows roughly the structure of the principal part of the said spraying method frame method. (A)-(C) are explanatory drawings which show roughly the structure of the bedrock adhesion construction method using the said spraying apparatus. It is explanatory drawing which shows roughly the structure of an example of the tunnel formation construction using the said spraying apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Aggregate 6 Cement milk 8 Conveyance pipe 9 Cement milk introduction part 9a Tapered part 10 Cement milk delivery pipe D Spraying apparatus M Mortar

Claims (3)

A mortar or concrete spraying device for separately spraying the aggregate and cement milk constituting the mortar or concrete, and then mixing and spraying the aggregate, the cement milk delivery pipe for transporting the cement milk, and the aggregate A transport pipe for transporting, and the transport pipe has a cement milk introduction part to which a downstream end of the cement milk delivery pipe is connected, and the cement milk introduction part has a taper whose inner diameter increases toward the downstream side. A cemented milk delivery pipe is connected to the tapered part so that the flow direction of the aggregate and the flow direction of the cement milk have an acute angle in the longitudinal section with respect to the tapered part. Features mortar or concrete spraying equipment. The mortar according to claim 1, wherein the cement milk delivery pipe is connected to the tapered portion at an angle so that the cement milk flowing into the conveyance pipe forms a spiral along the inner wall of the conveyance pipe. Or concrete spraying equipment. A mortar or concrete spraying device that sprays the aggregate and cement milk that make up mortar or concrete separately, and then mixes and sprays the nozzle and the nozzle at the downstream end of the transport pipe that transports the mixed aggregate and cement milk The nozzle portion has, in order from the upstream side, a widened portion whose inner diameter increases toward the downstream side and a throttle portion whose inner diameter decreases toward the downstream side, and the downstream end of the throttle portion. The mortar or concrete spraying device is characterized in that the inner diameter of the mortar is equal to or slightly larger than the inner diameter of the transport pipe.

Images