JPH05208149A - Concrete spray device - Google Patents

Abstract

PURPOSE:To efficiently accelerate a concrete material by compressed air without allowing friction force to act on the concrete material from the inner peripheral surface of a feed hose by supplying compressed air going toward a spray nozzle to the outer peripheral part of a feed passage in the vicinity of the discharge port of a sprayer. CONSTITUTION:The concrete material M reaching the area immediately before a discharge port 18 is allowed to flow to the feed passage R formed in a feed hose 4 by the compressed air A from an air jet part 21 through the discharge pipe 24 within a booster 22. Whereupon, since the compressed air from an air jet pipe 25 has kinetic inertia parallel to the rib 17b of a bottom plate 17 at the position close by the discharge port 18, the rib 17b hardly obstructs the flow of compressed air. Therefore, the concrete material is efficiently accelerated from a sprayer and the length of the feed hose 4 can be extended.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a concrete spraying device for spraying concrete, mortar, etc., with compressed air onto a construction site in a civil engineering work site or the like.

[0002]

2. Description of the Related Art A concrete spraying device includes a spraying machine,
It has a spray nozzle attached to the tip of a transfer hose extended from the spray machine, supplies concrete material to the spray machine, and transfers the concrete material from the spray machine to the spray nozzle with compressed air. , There is a method in which the concrete material is sprayed from the spray nozzle to the construction site with the compressed air.

In this type of spraying device, since it is necessary to facilitate the work such as supplying concrete material to the spraying machine, the spraying machine is installed at a position slightly apart from the construction site, and the desired concrete spraying work is facilitated. Therefore, the spray nozzle is connected as a separate body from the spray machine via the transfer hose,
The spray nozzle is used by being positioned in the immediate vicinity of the construction site.

In general, in order for the concrete spraying work by the spraying device to be performed well, it is necessary to make the injection speed of the concrete from the spraying nozzle a certain value or more.

[0005]

However, in the spraying apparatus of this type, as described above, the compressed air is used to transfer the concrete material through the conveying hose prior to the concrete spraying work. If the pressure loss accompanying the material transfer is large, the spraying energy of concrete is reduced, and a sufficient spraying speed cannot be secured, making it difficult to spray well.

Therefore, the length of the transfer hose is limited in the concrete spraying device of this type.

This means that at the construction site, the degree of freedom of the installation position of the spraying machine is reduced, which leads to a reduction in workability of work such as supplying concrete material to the spraying machine.

Particularly, in this type of spraying machine, the concrete material is in the initial stage of acceleration by the compressed air at the site on the downstream side in the vicinity of the discharge port, so that the acceleration toward the spraying nozzle is not sufficient and the static inertia It is in a big state.

Therefore, the concrete material tends to come into contact with the inner peripheral surface of the transfer hose, and a frictional force acts on the concrete material from the inner peripheral surface of the transfer hose to accelerate the concrete material against the frictional force. Therefore, much energy of the compressed air is consumed, resulting in a large pressure loss.

The present invention has been made based on such a background, and in this type of spraying device, the flexibility of the installation position of the spraying machine is increased, and the workability of the spraying machine such as the concrete material replenishing work is improved. The purpose is to improve.

[0011]

In order to achieve this object, the invention as set forth in claim 1 receives a concrete material, accelerates the concrete material with compressed air and discharges it from a discharge port, and this spraying machine. A transport hose extended from the spray hose and a spray nozzle connected to the tip of the discharge hose, and the concrete material discharged from the spray machine is compressed air to form a transport path inside the transport hose or the like. In the concrete spraying device for transporting the air toward the spray nozzle and spraying the spray nozzle, the compressed air that is directed toward the spray nozzle is provided to the outer peripheral portion of the transport path at a portion near the discharge port of the spray machine. It is characterized by doing.

[0012]

According to the first aspect of the present invention, the compressed air toward the spray nozzle side is supplied to the outer peripheral portion of the conveying path at a portion near the discharge port of the spraying machine. Even if the stationary inertia is large, the compressed air supplied here is forcibly pushed up to the central portion of the cross section of the transfer hose and separated from the inner peripheral surface.

Therefore, the frictional force from the inner peripheral surface of the transfer hose does not act on the concrete material, the concrete material is efficiently accelerated by the compressed air from the spraying machine, and the pressure loss of the compressed air is reduced. The length can be increased.

Therefore, in this type of concrete spraying device, the degree of freedom of the installation position of the spraying device is increased, and the spraying device can be installed at a position where the required work such as replenishment of concrete material can be easily performed. The workability of can be improved.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to an embodiment shown in the drawings. The concrete spraying device in this embodiment is a so-called dry concrete spraying device.

First, the overall outline of the dry concrete spraying device will be described with reference to FIG.

Reference numeral 1 denotes an entire dry concrete spraying device (hereinafter simply referred to as a device), and 2 denotes a dry concrete spraying device (hereinafter simply referred to as a spraying device).

A spray nozzle 3 is connected to the tip of a transfer hose 4 extending from the spray machine 2.

A water supply unit 5 is installed at a position of the transfer hose 4 immediately adjacent to the spray nozzle 3, and a water supply hose 7 extending from a water tank 6 is connected to the water supply unit 5.

In this apparatus 1, a so-called dry mix concrete material (hereinafter, simply referred to as material) M, which is a mixture of cement, sand, crushed stone and the like in a dry state, is supplied to the spraying machine 2 as a concrete material, which is in a dry state. When the material M is transported to the spray nozzle 3 side through the transport path R in the transport hose 4 and reaches the water supply section 5, a predetermined amount of water is supplied to the material M in the water supply section 5 and the slurry is sprayed from the spray nozzle 3. The material M is injected toward the construction site.

The spraying machine 2 of the apparatus 1 is constructed as follows (FIG. 3).

From the hopper 11 of the spraying machine 2 to the material M.
Is supplied, and the screen 12 prevents intrusion of aggregate particles having an excessively large particle diameter into the machine. In this embodiment, it is the cement, sand and aggregates such as crushed stone having a particle size of 15 mm or less and other additives that are accepted in the machine as the material M by the screen 12, and the water content thereof is It is in a dry state of 3% or less.

The material M supplied to the hopper 11 is sequentially supplied to the feeder 13 from the hopper 11, and the feeder 13 is provided with a feeder head 14 which is rotationally driven by a hydraulic pressure around a horizontal axis.

A pocket 15 is formed in the feeder head 14, and the material M is weighed in the pocket 15 and supplied to the pressure chamber 16 in a batch manner.

In this embodiment, the compressed air A is blown from the nozzle 13a toward the downward facing pocket 15 to ensure that the material M in the pocket 15 falls into the pressure chamber 16 and the interior of the pocket 15 is closed. The compressed air A blown into is discharged from the air bleeding pipe 13b into the atmosphere by the rotation of the feeder head 14 so that the next material M is reliably supplied to the pocket 15.

Incidentally, from the nozzle 13a to the pocket 15
The compressed air A blown onto the air is supplied from an air tank 31 described later through an air pipe provided with a throttle valve, and its flow rate and pressure can be adjusted by operating the throttle valve.

Material M from the pocket 15 as described above
The pressure chamber 16 is supplied with compressed air A from the nozzle 16a and is in a constant pressure state. The compressed air A supplied from the nozzle 16a is also supplied from an air tank 31 described later through an air pipe equipped with a throttle valve, and the flow rate and pressure can be adjusted by operating the throttle valve.

Inside the pressure chamber 16, a bottom plate 17 formed in a middle height is installed, and an arm 17a extending from the center of the bottom plate 17 to the peripheral side and the peripheral part of the bottom plate 17 are arranged in the radial direction. The upright guide rib 17b is integrally provided.

The bottom plate 17 is hydraulically driven to rotate about a central axis O installed in the vertical direction, and the arm 17a.
The material M supplied into the compression chamber 15 by the guide ribs 17b is prevented from being concentrated in one place in the pressure chamber 16, and is uniformly dispersed and arranged in the peripheral portion of the bottom portion.
The uniformly distributed material M is sequentially positioned immediately before the discharge port 18 (see FIG. 4).

The following booster 22 is installed outside the discharge port 18.

That is, the booster 22 has a mounting plate 23.
And the discharge pipe 24 and the air injection pipe 2 fixed to the mounting plate 23.
5, a first air port 26, a baffle plate 27, a taper pipe 28 fixed to the discharge pipe 24, and a second air port 29.
And the discharge pipe 24 are attached to the spraying machine 2 so as to be located immediately downstream of the discharge port 18.

The material M that has arrived just before the discharge port 18 as described above passes through the discharge pipe 24 in the booster 22 by the compressed air A from the air injection unit 21 configured as follows and the transfer hose 4 and the like. It flows out to the conveyance path R formed inside the.

The air injecting section 21 positions the air injecting pipe 25 of the booster 22 at a position just above the discharge port 18,
The air injection pipe 25 is provided so as to project toward the center of the bottom plate 17 and has its tip bent downward.

Therefore, the compressed air injected from the air injection pipe 25 has a motion inertia parallel to the guide rib 17b formed on the bottom plate 17 at the position immediately adjacent to the discharge port 18, so that the guide rib 17b is air-injected. The structure is such that the flow of the compressed air from the pipe 25 is less obstructed and the pressure loss of the compressed air is small.

In the spraying machine 2 of this embodiment, the material M is received in the pressure chamber 16 through the hopper 11 intermittently in batches by the feeder 13 as described above, but from the discharge port 18. The material M is discharged from the guide rib 1
Since the continuous rotation of the bottom plate 17 with 7b and the compressed air continuously jetted from the air jet pipe 25 are performed,
A constant amount of the material M is continuously discharged from the discharge port 18 without interruption.

The air injection unit 21 has a baffle plate 27 extending on both sides at the tip of the air injection pipe 25, and the material accelerated by the compressed air from the air injection pipe 25 by the baffle plate 27. M does not scatter in the pressure chamber 16,
The material M can be efficiently discharged to the discharge port 18.

The compressed air A is supplied from an air compressor (not shown) to the air tank 3 which also serves as the base of the sprayer 2.
1 is supplied to the air injection pipe 25 from the air tank 31 via the first air port 26 by an air pipe line (not shown), and a manually operated throttle opening / closing is provided in the air pipe line. A valve is installed so that the compressed air flow rate and pressure from the air injection pipe 25 can be adjusted appropriately. And, in this embodiment, the air pressure from the air compressor is, for example, 6 kg / cm ² , and the flow rate is, for example, 4 to 18 m ³ / h.
Is.

The second air port 29 of the booster 22 is also connected to the air pipe from the air tank 31 and is supplied with the compressed air A.

The compressed air supplied to the second air port 29 flows into the taper pipe 28 as shown in FIG.

Inside the taper pipe 28, the discharge pipe 24 is installed on the central axis of the taper pipe 28.
Of the open end of the taper pipe 28
Of the taper pipe 28 on the outer peripheral portion of the conveying path R where the material M is located in the cross section.
The compressed air A from is formed in layers over the entire circumference.

The material M discharged from the tip of the discharge pipe 24 is accelerated by the compressed air A from the air injection pipe 25, and the inside of the taper pipe 28 is wrapped so as to cover the entire outer circumference of the flow of the material M. Since the flow of the compressed air A is formed from the side toward the spray nozzle 3 side, in the transfer path R formed inside the second taper pipe 32 or the transfer hose 4 installed on the downstream side of the taper pipe 28. The material M is pushed up to the center of the cross section and is separated from the inner peripheral surface.

As a result, the frictional force from the second taper pipe 32 or the inner peripheral surface of the transfer hose 4 does not act on the material M, and the material M is discharged from the air injection pipe 25 or the second air port 29. The compressed air A is efficiently and quickly accelerated, and the pressure loss of the compressed air is reduced.

In particular, in the vicinity of the discharge port of this kind of spraying machine, generally, when the concrete material is transferred, a large energy of the compressed air is generated by the frictional force which the concrete material receives from the inner peripheral surface of the transfer hose. Since the consumption is greatly reduced, the pressure loss is remarkably reduced.

The material M accelerated in this way blows on the conveying path R such as the conveying hose 4 by the compressed air A and the spray nozzle 3
It is transferred toward the side and reaches the water supply unit 5 (see FIG. 5).

A water supply hose 7 extending from a water tank 6 is connected to the water supply unit 5 and transferred in the transfer hose 4.
A predetermined amount of water is supplied to the material M, and the water supply section 5 is generally composed of a water supply section main body 36 and a spray nozzle 3.

An annular groove 36a is formed on the inner surface of the water supply body 36.
Is formed, and the water supply hose 7 is connected so as to communicate with the annular groove 36a.

Inside the water supply section body 36,
The tip of the transfer hose 4 and the end 3a of the spray nozzle 3 are fitted and attached from both sides.

The end portion 3a of the spray nozzle 3 comprises:
The annular groove 36a is attached to the water supply body 36.
A large number of injection holes 37 are formed in a three-layered shape in a portion facing to, and the high pressure water supplied to the annular groove 36 is injected from each injection hole 37 toward the inside.

Each of the injection holes 37 forming the first layer 41 is formed in a plane orthogonal to the central axis of the spray nozzle 3, and each of them is formed from the lower side to the upper side in FIG.

Each of the injection holes 37 forming the second layer 42 is formed in a separate surface orthogonal to the central axis of the spray nozzle 3 at a position slightly downstream of the first layer 41, both of which are shown in FIG. The injection holes 37 that are formed in the vertical direction and that form the third layer 43 are formed from the upper side to the lower side in FIG. 5 in an orthogonal plane that is further downstream than the second layer 42.

The injection holes 37 forming the layers 41, 42, 43 are formed in parallel for each layer, and the injection direction of the high-pressure water from each injection hole 37 is the layer 41, 42.
42 and 43 are parallel to each other.

Therefore, in the water supply section 5, the high-pressure water from the injection holes 37 forming the layers 41, 42, 43 forms a grid pattern orthogonal to each other when viewed from the central axis direction of the spray nozzle 3.

Therefore, the material M that reaches the water supply section 5
The water is supplied by such a grid-shaped high-pressure water, so that the water can be supplied evenly.

In this embodiment, the spraying machine 2 is made of the material M.
Is to discharge a uniform amount continuously as described above,
Since the water supply unit 5 also continuously supplies a uniform amount of water to the material M, the water-cement ratio of the slurry-like material M to which water has been added is uniform and uniform.

A predetermined amount of water is supplied in this way, and the slurry-like material M is sprayed by the worker from the tip of the spray nozzle 3 toward the construction site, and the required spraying work is performed.

In the embodiment described above, the apparatus 1 is a dry concrete spraying apparatus, but the present invention can be similarly applied to a wet concrete spraying apparatus.

When the present invention is carried out in a dry concrete spraying device, it is not limited to the spraying machine 2 and, for example,
The same operation can be performed by using a so-called revolver spraying machine, which discharges the material M intermittently by using compressed air.

[0058]

As described above, according to the first aspect of the present invention, the compressed air directed to the spray nozzle side is supplied to the outer peripheral portion of the conveyance path at a portion near the discharge port of the spray machine. Therefore, even if the concrete material has a large static inertia in this part, the compressed air supplied here is forcedly pushed up to the central portion of the cross section of the transfer hose and separated from the inner peripheral surface. Become.

Therefore, the frictional force from the inner peripheral surface of the transfer hose does not act on the concrete material, the concrete material is efficiently accelerated by the compressed air from the spraying machine, and the pressure loss of the compressed air is reduced. The length can be increased.

Therefore, in this type of concrete spraying device, the degree of freedom of the installation position of the spraying device is increased, and the spraying device can be installed at a position where the required work such as replenishment of concrete material can be easily performed. The workability of can be improved.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a main part.

FIG. 2 is an overall schematic view of a dry concrete spraying device.

FIG. 3 is a vertical sectional view of a spraying machine.

FIG. 4 is a sectional view taken along line XX in FIG.

FIG. 5 is a vertical sectional view of a water supply unit.

[Explanation of symbols]

A Compressed air M Concrete material (dry mix) R Conveying path 1 Concrete spraying device (Dry concrete spraying device) 2 Spraying machine (Dry concrete spraying device) 3 Spraying nozzle 4 Conveying hose 5 Water supply part 18 Discharge port 22 Booster

Claims (3)

[Claims] 1. A spraying machine for receiving a concrete material, accelerating it with compressed air and discharging it from a discharge port, a transfer hose extending from the spraying machine, and a spraying nozzle connected to the tip of the discharge hose. In a concrete spraying device having a spraying machine, the concrete material discharged from a spraying machine is transported by compressed air to a spraying nozzle while transporting a transporting path formed inside the transporting hose or the like toward the spraying nozzle. A concrete spraying device, characterized in that compressed air directed to the spray nozzle side is supplied to an outer peripheral portion of the transport path at a portion near a discharge port of the spraying machine. 2. The concrete spraying device according to claim 1, wherein the concrete material is dry mix,
A concrete spraying device, characterized in that a water supply unit is installed in the vicinity of the upstream side of the spraying nozzle to spray and supply water into the concrete material transferred through the transport path. 3. The concrete spraying apparatus according to claim 2, wherein the spraying machine continuously discharges the concrete material without interruption.