JPH1142446A - Concrete spraying system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a concrete spraying system capable of homogeneously spraying concrete at a long force feeding distance. SOLUTION: The pressure chamber in a force feeding machine 7 is maintained at the primary many pressure higher than the spraying pressure of a spraying nozzle 11 and an admixture composed of cement and aggregate is supplied by an airtight supplying device 6 to the pressure chamber. While the admixture is uniformly dispersed by the primary pressure air in the force feeding machine 7, the admixture is transported into a transporting pipe 8 communicating with the bottom end of the force feeding machine 7 and is further advanced into a pressure regulator 9 disposed at the terminal of the transporting pipe 8 in the tangent direction of the inside wall thereof. Water is poured to the admixture from a water ejection port disposed at the pressure regulator 9 and while the water and admixture are swirled and dropped by their own weight in the longitudinally long pressure regulator 9, both are mixed to form the fresh concrete. The air pressure is reduced down to a spraying pressure by a pressure reducing valve 52 disposed at the apex of the pressure regulator 9. The fresh concrete is transported by the air of the spraying pressure into a force feeding hose 10 communicating with the bottom end of the pressure regulator 9 and is sprayed from the spraying nozzle 11 disposed at the terminal of the force feeding hose 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a concrete spraying system, and more particularly to a system for mixing and conveying cement and aggregate at a primary pressure higher than the spraying pressure of a spraying nozzle and reducing the spraying pressure at the end of the primary pressure transfer. The present invention relates to a concrete spraying system.

[0002]

2. Description of the Related Art Referring to FIG. 1, fresh concrete immediately after mixing is delivered to a pressure hose 10 at a spray pressure of about 7 kg / cm ² in order to strengthen the surface of the ground 13 with concrete. A wet concrete spraying system is used in which an operator 12 manually sprays the spray nozzle 11 at the end of the spraying to the ground surface or the like.

[0003]

In the conventional wet concrete spraying system, when the distance from the delivery end of fresh concrete to the spraying nozzle 11 is about 120 m or more,
There has been a problem that materials such as aggregates and cement are separated or pulsation occurs in pressure, and it is difficult to uniformly spray concrete. At the feed end, the dry feed method is to mix only the powder materials such as cement, aggregate, and necessary auxiliaries without adding water, and to add water with a spray nozzle.The length of the pumping hose is about 300 m horizontally and about 200 m vertically. It is said that it can be extended. However, when the length of the pressure-feeding hose is increased by the dry method, there is a disadvantage that it is difficult to ensure a constant quality of the sprayed concrete. The wet method in which fresh concrete is mixed at the delivery end has a drawback that the workability is low due to the limitation of the length of the pumping hose described above.

Accordingly, it is an object of the present invention to provide a concrete spraying system which has a long pumping distance and can ensure high quality spraying.

[0005]

As a result of a study by the present inventors on a technique for extending the pumping distance while ensuring high quality, the pumping pressure, which was conventionally equal to the spraying pressure of the spray nozzle, was reduced by the spraying pressure. Attention was paid to a method of transporting cement, aggregate, and the like with a high primary pressure, and reducing the primary pressure of the transport to a spray pressure in the vicinity of the cement spraying position. However, when a high primary pressure is used, there is a problem that air leakage or pressure drop is likely to occur at a supply port when supplying a material to a pressure chamber for mixing the material at the primary pressure.

The present invention has been accomplished by solving this problem through research and experiment.

Referring to FIG. 1, in a concrete spraying system 1 according to the present invention, a mixture of cement and aggregate is hermetically sealed into a pressure chamber 38 (see FIG. 2) of a pump having a primary pressure higher than the spray pressure of a spray nozzle 11. While the mixture is uniformly dispersed under the primary pressure by the feeder 7 and sent out into the transport pipe 8 communicating with the lower end of the pressure chamber 38. The water is fed into the pressure regulator 9, water is injected into the mixture through a water outlet 55 (see FIG. 4) provided in the pressure regulator 9, and the water and the mixture are mixed in the pressure regulator 9 to obtain fresh water. The concrete is reduced and the pressure is reduced to the spray pressure by the pressure reducing valve 52 at the top of the pressure regulator 9. Do not spray from the spray nozzle 11 provided at the end. Things.

The injection of water into the mixture of cement and aggregate may be performed by the mixer 3.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the embodiment of FIG. 1, the pressure chamber 38 (see FIGS. 2 and 3) is used as the internal space of the pumping machine 7, but the pressure chamber 38 of the present invention is integral with the pumping machine 7. Is not necessarily required, and the present invention is not limited to this embodiment. FIG.
The pressure in the pressure chamber 38 is maintained at a primary pressure higher than the spray pressure (eg, about 7 kg / cm ² ) by a pressurized fluid supplied from a pressure source (not shown) through the air supply port 37. be able to. The exhaust port 36 is connected to an appropriate valve (not shown) for releasing the pressure in the pressure chamber 38 as required.

In order to prevent air from leaking when supplying cement and aggregate to the pressure chamber 38, the rotary feeder 6 shown in FIGS. 2 and 3 has an arrow R1 (FIG. 2) inside the cylindrical casing 29. , And a rubber seal 32 attached to a casing 29 via an air chamber 31. The rubber seal 32 is slidably and airtightly in contact with the outer peripheral surface of the rotor 30. By supplying compressed air to the air chamber 31 via the pressure valve 33, the rubber sheet 32 is
The rotor 30 is slidable in contact with the rubber sheet 32 at this time by sealing the outer surface of the rubber sheet 32 by pressing against the peripheral surface of the rubber sheet. The pressure relief valve 34 is for releasing compressed air from the air chamber 31 to release the close contact between the rubber sheet 32 and the peripheral surface of the rotor 30.

The rotor 30 is provided with a receiving hole 35 extending from its peripheral surface in the direction of the central axis. When the rotor 30 rotates and the receiving hole 35 faces upward, the mixture such as cement and aggregate in the shooter 5 is dropped into the receiving hole 35 via the drop port of the shooter 5, that is, the receiving port 29a of the cylindrical casing 29. . After that, the rotor 30 rotates and the receiving hole containing the mixture
When 35 faces downward, the outlet 29 of the cylindrical casing 29
The mixture is dropped from the receiving hole 35 to the lower pressure chamber 38 by its own weight via b. In this manner, cement, aggregate, and the like can be supplied to the pressure chamber 38 while maintaining the pressure chamber 38 at a primary pressure higher than the conventional spray pressure.

The illustrated pressure feeder 7 includes a rotary blade 40 and a feed blade 41 (see FIG. 3) mounted on a rotary shaft 39 on the center axis of the pressure chamber 38 and rotating in the direction of arrow R2 (FIG. 2). It comprises a rotating disk 42 attached to the end of the rotating shaft 39 on the delivery side. The inclined partitioning wall 43 on the rotary disk 42 is used to smoothly transport the mixture of cement, aggregate, and the like, which is pressure-fed by the rotary blades 40 and the feed blades 41, to the transport pipe 8 via the outlet 38 a directly below by its own weight. It is for dropping.

The mixture of cement, aggregate, etc., which has been pumped by the primary pressure from the pump 7 to the other end of the conveying pipe 8,
And mixed with water from the water outlet 55 to form fresh concrete, and the pressure is reduced to the spray pressure by a pressure reducing valve 52 (see FIG. 4) attached to the top of the pressure regulator 9. The fresh concrete at the spray pressure is sent to the spray nozzle 11 via a pressure feeding hose 10 communicating with the lower end of the pressure regulator 9, and is sprayed manually by an operator 12. In the embodiment of FIG. 4, the pressure regulator 9 has a funnel-shaped or vertical cylindrical pressure-regulating housing 50, the conveying pipe 8 is mounted so as to inscribe the inner wall of the upper end portion of the housing 50, and the water jet 55 is It is arranged so as to face the end of the transport pipe 8. The mixture such as cement and aggregate sent out from the transport pipe 8 at the primary pressure is sufficiently mixed with the water from the water jet port 55 and then descends while moving spirally along the inner wall of the housing 50 by its own weight. In the meantime, it mixes better with water to form fresh concrete. If necessary, as shown in FIG. 4B, a baffle plate 59 can be provided on the inner wall of the housing 50 as appropriate to promote the mixing of fresh concrete. The mixing process in the housing 50 absorbs the pulsation of the pumping of inclusions, such as cement and aggregates, which may occur in the conveying pipe 8 and provides a uniform and smooth pumping of fresh concrete from the pressure regulator 9 to the pumping hose 10. Secure.

Since the fresh concrete and its pressure delivered from the pressure regulator 9 are similar to those of the conventional wet concrete spraying system, the concrete spraying system of the present invention is at least as good as the conventional wet concrete spraying system. Can spray concrete with high quality. In addition, since a combination of the pumping of the mixture such as cement and aggregate by the transport pipe 8 at the primary pressure higher than the spray pressure and the mixing of the water and the mixture in the pressure regulator 9 is used, the conventional wet concrete spraying system is used. Ensure a homogeneous supply of cement and aggregate over long distances.

Accordingly, the object of the present invention is to provide a "concrete spraying system capable of ensuring a long pumping distance and high quality".

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Aggregates such as gravel and sand have hitherto been dropped into mixers and pumps after uniforming the particle size with a fixed sieve. In this conventional method, a lump of sand or large gravel does not pass through the wire mesh and remains on the wire mesh as it is, and the piles are piled up to overflow normal aggregate without passing through the wire mesh. The removal of the remaining lumps and gravels was performed manually by workers, resulting in unscheduled man-hours. The grizzly sieve 2 of the embodiment shown in FIG. 1 has a configuration in which a wire mesh 20 is rotated by a drive shaft 21 and a guide shaft 22 that rotate around an axis 21c. Wire mesh
The wire 20 is always pulled in the direction of rotation in the direction of arrow M and moves, so that sand or the like does not firmly adhere to the wire mesh 20. For this reason, the wire net 20 can always be used with the size of the mesh. Furthermore, undesired aggregate remaining on the wire mesh 20 is automatically removed by the rotation of the wire mesh itself, eliminating the need for manual removal by the operator. For this reason, the burden of labor is reduced and work safety is improved. If necessary, the wire mesh 20 may be washed by ejecting a cleaning material from the fluid ejection port 23.

After the aggregate is mixed with the cement by the mixer 3, the aggregate is sent to the shooter 5 by the concrete transporter 4 and dropped therein. The shooter 5 shown in FIG. 2 comprises a funnel-shaped member 24 and a rubber coating film 25 covering the inner surface thereof.
Air is injected into the back side of the rubber coating film 25 through the air supply valve 26 to expand the air, and the aggregate attached to the surface is forcibly discharged. The exhaust valve 27 is for exhausting air on the back side of the rubber coating film 25 to return the shooter 5 to a normal operation shape.

The side wall 35a of the receiving hole 35 of the rotor 30 of the rotary type feeder 6 is inclined so that the cross section of the hole 35 increases as the distance from the bottom surface 35b of the hole 35 increases, and the hole 35 faces downward. At times, the aggregate or the like easily separates from the inclined side wall due to its own weight and falls. Further, the sealed bearing formed by the outer peripheral surface of the rotor 30 and the rubber seal 32 is, for example, a rubber seal 32.
Even if there is a certain amount of wear, pressurization by the compressed air in the air chamber 31 always keeps high airtightness and the life as a bearing is very much compared to the conventional structure without the rubber seal 32 used together with the air chamber 31. long. In order to prevent the high-pressure air that has entered when the receiving hole 35 is facing downward from being ejected into the shooter 5 when the hole 35 is facing upward, the rubber seal 32 that comes into contact with the receiving hole 35 past the position facing the pressure chamber 38. An exhaust port 36 communicating with the outside of the supply device 6 may be formed in a portion of the above, and the pressure in the receiving hole 35 may be released at this portion.

An upward nozzle 44 faces the outlet 38a at the lower end of the pressure chamber 38, so that the separation of the aggregate and the like from the rotating disk 42 can be promoted. The transport air nozzle 45 may face the terminal of the transport pipe 8 on the side of the pumping device 7 to eject compressed air for transport. The embodiment of the pressure regulator 9 shown in FIG. 4 has a high-pressure inlet 51 provided in a direction inscribed in the inner wall of the upper end portion of the funnel-shaped or vertical cylindrical pressure-regulating housing 50, and the far end of the transport pipe 8 has Connected to high pressure inlet 51. In the case of a dry type in which a water jet 55 supplied with water through a water supply valve 54 is provided at a portion facing the high-pressure inlet 51, and only powder such as a mixture of cement and aggregate is pumped by the transport pipe 8. Is mixed with powder such as the mixture thereof and water at the upper end of the housing 50,
As shown in FIGS. 4 (A) and (B), they are mixed with fresh concrete as they fall while moving spirally under their own weight. If necessary, a stirring air supply port 56 may be provided to blow compressed air in a direction that promotes spiral movement and stirring. A pressure feeding hose 10 is connected to the blowing pressure outlet 53 at the lower end of the pressure regulating housing 50, and fresh concrete reduced in pressure from the primary pressure to the blowing pressure is sent out to the blowing nozzle 11. If necessary, make the supply port 57 for mixing the quick-setting binder and other auxiliaries face the spraying pressure outlet 58, and in order to promote the delivery of fresh concrete, connect the blowing air nozzle 58 with the pressure hose 10
You may face.

In the case of a completely wet type in which water is mixed with cement and aggregate at or before the pump 7, the water jet 55 of the pressure regulator 9 can be omitted. Also the pressure hose 10
Only powder and water into the spray nozzle 11,
In the case of a completely dry type in which fresh concrete is mixed immediately before spraying, the water jet 55 in the pressure regulator 9 can be omitted.

[0021]

As described above, the concrete spraying system according to the present invention can be used under a primary pressure higher than the spraying pressure of the spraying nozzle to remove cement or aggregate powder alone or a mixture of water and water. After being conveyed to the vicinity of the spraying position by the conveying pipe, it is mixed with fresh concrete by a pressure regulator, reduced to the spraying pressure and fed into a conventional pressure feeding hose, so that the following remarkable effects are exhibited.

(B) The distance from the pump to the spray nozzle can be made longer than in the conventional system in which only the spray pressure is used to perform the pumping and spraying. (B) By using a pressure regulator, pressure pulsation can be absorbed and reduced. (C) Even if powder such as cement or aggregates is partially separated during transportation, uniform concrete or concrete material can be continuously supplied to the spray nozzle by mixing in the pressure regulating chamber.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory diagram of one embodiment of the present invention.

FIG. 2 is a schematic longitudinal sectional view of a rotary feeder and a pump.

FIG. 3 is a cross-sectional view in the direction of arrows III-III in FIG.

FIG. 4 is an explanatory diagram of a pressure regulator.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Concrete spraying system 2 ... Grizzly sieve 3 ... Mixer 4 ... Concrete transporter 5 ... Shooter 6 ... Rotary feeder 7 ... Pumping machine 8 ... Transporting pipe 9 ... Pressure regulator 10 ... Pressure feeding hose 11 ... Spray nozzle 12 ... Worker 13 ... ground 20 ... wire mesh 21 ... drive shaft 22 ... guide shaft 23 ... fluid outlet 24 ... funnel-shaped member 25 ... rubber coating film 26 ... air supply valve 27 ... exhaust valve 29 ... cylindrical casing 30 ... rotor 31 ... air Chamber 32… Rubber seal 33… Pressure valve 34… Release valve 35… Reception hole 36… Exhaust port 37… Supply port 38… Pressure chamber 39… Rotating shaft 40… Rotating blade 41… Feeding blade 42… Rotating disk 43… Incline Partition wall 44… Upward nozzle 45… Conveying air nozzle 50… Pressure control housing 51… High pressure inlet 52… Reducing valve 53… Blowing pressure outlet 54… Water supply valve 55… Water outlet 56… Agitated air supply port 57… Refill port 58… Spray air nozzle 59 ... Baffle plate

Claims (9)

[Claims] An airtight supply of a mixture of cement and aggregate to a pressure chamber in a pump having a primary pressure higher than the spray pressure of a spray nozzle.
The mixed material is uniformly dispersed under the primary pressure by the pump, and is sent out into a transfer pipe communicating with a lower end of the pressure chamber, and further sent into a pressure regulator provided at an end of the transfer pipe. Water is injected into the mixture from a water outlet provided in the pressure regulator, and the water and the mixture are mixed in the pressure regulator to produce fresh concrete, and the spray pressure is reduced by a pressure reducing valve at the top of the pressure regulator. Reduce the pressure to
A concrete spraying system for discharging concrete under a spray pressure into a pumping hose communicating with a lower end of a pressure regulator and spraying from a spray nozzle provided at an end of the pumping hose. 2. A mixture of cement, aggregate and water is airtightly supplied to a pressure chamber in a pump having a primary pressure higher than a spray pressure of a spray nozzle, and the mixture is reduced by the pump at a primary pressure. While being dispersed in the same manner, the mixture is sent out into a transfer pipe communicating with the lower end of the pressure chamber, and further sent into a pressure regulator provided at the end of the transfer pipe. At the same time, the pressure was reduced to the spray pressure by the pressure reducing valve at the top of the pressure regulator, and the fresh concrete was delivered under the spray pressure into the pressure hose connected to the lower end of the pressure regulator, and provided at the end of the pressure hose. A concrete spraying system sprayed from a spray nozzle. 3. The spraying system according to claim 1, wherein
A concrete spraying system in which the particle size of the aggregate is adjusted by a grizzly sieve made of a rotating or reciprocating wire mesh, the aggregate is mixed with cement by a mixer, and then airtightly supplied to a pressure chamber in the pumping machine. 4. The spraying system according to claim 1, wherein the airtight supply to the pressure chamber in the pump is opposed to a cylindrical casing having a horizontal central axis and the casing inner wall via a gap. A solid cylindrical rotor having a rotating peripheral surface, a film-shaped rubber seal hermetically disposed over the inner wall of the casing, a pressure valve and a pressure relief valve that penetrate the casing and open between the inner wall of the casing and the rubber seal,
A rotary hole comprising a receiving hole fitted in the central axis direction from the peripheral surface of the rotor, and a receiving port and a discharging port which are hermetically bored in the casing and the rubber seal at portions opposed to the receiving holes facing upward and downward when the rotor rotates. A pressurized fluid is fed between the casing inner wall and the rubber seal through the pressurizing valve when the rotor rotates, and the rubber seal is slidably adhered to the rotor peripheral surface when the rotor rotates, and the receiving port is connected to the receiving port. The discharge port is airtightly separated, and when the receiving hole is upward, the mixed substance is sent into the receiving hole through the receiving port, and when the receiving hole is downward, the mixed substance is discharged through the discharge port by its own weight. A concrete spraying system that is dropped. 5. The concrete spraying system according to claim 4, wherein an exhaust port is hermetically pierced in said casing and rubber seal at a position facing said receiving hole after passing through said discharge port when said rotor rotates. 6. The spray system according to claim 4, wherein
The upper end of the pressure chamber is communicated with a discharge port of the supply device, and an air supply port communicating with the pressure source of the primary pressure and an exhaust port communicating with a valve are bored in the pressure chamber. A concrete spraying system comprising: a rotary feed blade fixed to a horizontal rotary shaft, a rotary disk provided at a delivery end of the horizontal rotary shaft, and a discharge port communicating with the transport pipe below the rotary disk. 7. The spraying system according to claim 1, wherein the pressure regulator is provided with a vertical hollow cylindrical pressure regulating housing, and a high pressure provided in a direction in which the pressure regulating housing is inscribed in an upper end portion inside the pressure regulating housing. An inlet, a pressure reducing valve provided at the top of the pressure regulating housing, a water jet provided near the high pressure inlet, and a spray pressure outlet formed at the lower end of the pressure regulating housing are provided to the high pressure inlet. Water is poured into the mixture of cement and aggregate, mixed with fresh concrete while turning the water and the mixture by their own weight downward along the inner wall of the pressure regulator, and sprayed by a pressure reducing valve at the top of the pressure regulator. A concrete spraying system which is depressurized to a pressure and sent out from the low pressure outlet. 8. The pressure spraying system according to claim 2, wherein the pressure regulator is provided with a vertical hollow cylindrical pressure regulation housing, and a high pressure provided in a direction inscribed in an upper end portion inside the pressure regulation housing. An inlet, a pressure reducing valve provided at the top of the pressure regulating housing, and a spray pressure outlet formed at the lower end of the pressure regulating housing are provided, and a mixture of cement, aggregate, and water fed to the high pressure inlet is self-weighted. The concrete spraying system mixes with fresh concrete while swirling downward along the inner wall of the pressure regulator, and reduces the pressure to the spray pressure by a pressure reducing valve at the top of the pressure regulator, and sends out from the low pressure outlet. 9. The spraying system according to claim 7, wherein
A concrete spraying system comprising an auxiliary agent replenishing port provided at a portion of the pressure regulator facing the spray pressure outlet.