JPH0474057B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a Coanda type cleaning nozzle, which can be used for cleaning piping in chemical plants, petroleum refining plants, etc.

[Conventional technology]

Traditionally, in plants with a large number of pipes, in order to prevent dirt and clogging in the pipes,
Piping is cleaned regularly. When cleaning such piping, the general method is to open both ends of the piping to be cleaned, attach a cleaning nozzle, etc. to one end, and supply a high-pressure water stream containing the cleaning liquid. Solid matter adhering to the inner wall surface of piping is removed by the frictional force of water pressure or the impact force of water pressure.

[Problem that the invention seeks to solve]

However, when cleaning the inside of a pipe by pumping liquid, it is necessary to dispose of the cleaning liquid discharged from the other end of the pipe during cleaning, and there is a limit to the flow rate of the liquid within the pipe. The cleaning effect is obtained exclusively by increasing the liquid pressure. However, in order to pump the cleaning liquid at high pressure, a large pump or the like is required, which makes handling complicated, and if the pipe to be cleaned is clogged with solid matter, etc.
When a pressurized water stream is suddenly sent, there is a problem in that the pressure inside the piping becomes extremely high, causing the cleaning nozzle etc. to be blown away, which is dangerous.

An object of the present invention is to provide a Coanda type cleaning nozzle that is highly safe and workable, has a simple structure, and is capable of highly efficient cleaning.

[Means for solving problems]

The present invention provides a diversion passage having an inlet and a discharge port in a main body, and an injection jet formed in the circumferential direction of the diversion passage and capable of injecting compressed air supplied from the outside into the diversion passage in a radial direction. a Coanda surface that bulges out continuously from the inner wall surface of the injection port into the guide passage, is smoothly curved to have a substantially arcuate cross section, and is continuous with the inner wall surface on the discharge port side of the guide passage; A Coanda-type cleaning nozzle is constructed by providing a cleaning liquid supply pipe that opens approximately at the center of the guiding passage surrounded by the Coanda surface and is capable of supplying cleaning liquid into the guiding passage.

[Effect]

In the present invention configured in this way, the jet of compressed air from the injection port is deflected toward the discharge port side by the Coanda effect on the Coanda surface,
By forming a flow from the suction port to the discharge port in the guide passage, sucking out the cleaning liquid from the cleaning liquid supply pipe, turning it into a mist, and discharging it from the discharge port, the high-speed air containing the cleaning liquid droplets is removed from the cleaning liquid. By applying the cleaning liquid to the object for cleaning, there is no need to apply high pressure to the cleaning liquid, increasing safety, eliminating the need for a large pump, simplifying the structure and making it easier to handle, and reducing the amount of liquid to reduce waste liquid. Facilitates processing operations,
As described above, the workability is improved and the above object is achieved.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

A first embodiment of the invention is shown in FIGS. 1 and 2. FIG. In FIG. 1, a Coanda type cleaning nozzle 1 of this embodiment is attached to the end of a pipe 2 to be cleaned, and generates a high-speed jet stream using compressed air from a compressed air supply means 3 equipped with a compressor or the like. At the same time, the inside of the pipe 2 is cleaned by making the cleaning liquid from the cleaning liquid supply means 4 into a mist and spraying it together with a jet stream.

This Coanda type cleaning nozzle 1 has a cylindrical flow guide passage 10 with a substantially circular cross section in the center, and this flow guide passage 10 has a suction port 1 whose left end in the figure is open to the outside air.
1, and the left end in the figure is a discharge port 12 that is continuous with the pipe 2, and in the middle is a substantially slit that continues in the circumferential direction of the guide passage 10 and supplies compressed air into the guide passage 10. A shaped injection port 20 is formed.

A substantially doughnut-shaped pressure accumulation tank 21 is provided on the outer periphery of this injection port 20, and this pressure accumulation tank 21 is
It is connected to the compressed air supply means 3 via the compressed air supply valve 22, and injects the compressed air supplied thereinto from the jet nozzle 20 into the guide passage 10, and at the same time, there are holes arranged at predetermined intervals along the jet nozzle 20 inside. A pressure equalizing weir 23 is provided in the jet nozzle 20 to provide an appropriate flow resistance to the compressed air so that the distribution of the compressed air flowing into the injection port 20 in the circumferential direction becomes uniform.

Further, a Coanda surface 30 is provided on the discharge port 12 side of the injection port 20, and this Coanda surface 30 is
It bulges out continuously from the inner wall surface of the injection port 20 into the guide passage 10, is smoothly curved so as to have a substantially arcuate cross section, and is continuous with the inner wall surface of the guide passage 10 on the discharge port 12 side. The jet of compressed air from the injection port 20 is deflected along the Coanda surface 30 by the Coanda effect on the Coanda surface 30, and
It is constructed so that it flows towards the two sides.

As shown in FIG. 2, the discharge port 12 is provided with a substantially U-shaped connecting member 40. As shown in FIG. This connecting member 40 has a groove 41 on the inner periphery of a substantially U-shaped portion,
By inserting the flange 2A of the pipe 2 into this groove 41 from below in the figure, the pipe 2 and the flow guide passage 10 can be connected, and at this time, the inner wall surface of the pipe 2 and the Coanda surface 30 are substantially continuous. It is configured to Further, the connecting member 40 has a substantially U-shaped fixing member 42 that is rotatable on the open side, and this fixing member 42 is biased by a biasing means such as a spring (not shown), and usually the first As shown in the figure, it can be rotated toward the piping 2 side to hold down the flange 2A of the piping 2 and fix it.

On the other hand, the suction port 11 side of the flow guide passage 10 is the discharge port 1
2 and piping 2, and can suck in a large amount of outside air due to the negative pressure caused by the jet flowing along the Coanda surface 30, and this suction port 11
A cleaning liquid supply pipe 50 is provided at the peripheral portion of the cleaning liquid supply pipe 50 . The cleaning liquid supply pipe 50 has its proximal end connected to the cleaning liquid supply means 4 via a cleaning liquid supply valve 51, and its distal end guided into the flow guide passage 10 from the suction port 11 and surrounded by the Coanda surface 30. The opening 52 at the tip thereof is directed toward the discharge port 12, and the cleaning fluid from the cleaning fluid supply means 4 is moved from the suction port 11 to the discharge port 12 by a so-called ejector effect. It is configured so that it can be sucked out and supplied into the flow guide passage 10 in the form of a mist.

In this embodiment configured as described above, the Coanda type cleaning nozzle 1 is attached to the end of the pipe 2 by the connecting member 40, and the compressed air supply valve 22 is opened to supply compressed air from the compressed air supply means 3. is supplied and injected into the diversion passage 10 from the injection port 20, and the jet is deflected along the Coanda surface 30 to generate a high-speed flow in the diversion passage 10 from the suction port 11 toward the discharge port 12. At this time, the jet deflected along the Coanda surface 30 is adiabatically expanded by the inertial force accompanying the sudden deflection, and is expanded to about 1/100.
The pressure is reduced to a certain degree (Prandtlmeyer flow),
The flow velocity of the outside air and the jet flow sucked by this negative pressure is accelerated to a high speed higher than the speed of sound at the discharge port 12 when the pressure of the compressed air supplied to the injection port 20 is 7 kg/cm ² .

Here, when the cleaning liquid supply valve 51 is opened, the cleaning liquid supply pipe 5 is
Negative pressure is generated in the opening 52 of the cleaning liquid supply means 4, and the cleaning liquid from the cleaning liquid supply means 4 is sucked into the flow guide passage 10, is scattered by the flow, becomes a mist, and is sent along with the flow to the discharge port 12 side. It will be done. For this reason, a high-speed air flow containing mist-like cleaning liquid droplets is sent to the piping 2 from the discharge port 12, and the inner wall surface of the piping 2 is cleaned by the impact force and the action of the cleaning liquid.

According to this example configured in this way, the following effects are achieved.

In other words, the inside of the pipe 2 can be efficiently cleaned by sending a mist of cleaning liquid along with a high-speed airflow to the pipe 2, removing deposits by the impact force of the airflow, and washing them away with the cleaning liquid. I can do it.

In addition, negative pressure is generated on the side of the suction port 11 in the guide passage 10 to suck external air from the suction port 11, and accelerate it with a jet flow along the Coanda surface 30 to form a unified flow. The flow rate of air flowing through the guide passage 10 can be made larger than the flow rate of compressed air from the compressed air supply means 3.

Therefore, the cleaning effect inside the pipe 2 can be further enhanced, and even if the flow rate of compressed air from the compressed air supply means 3 is small, a sufficient flow rate can be obtained, so the capacity of the compressor, etc. of the compressed air supply means 3 can be increased. can be small, the device can be downsized, and the power required for operation can be reduced.

Furthermore, since the jet of compressed air from the injection port 20 flows along the Coanda surface 30 and surrounds the outside air from the suction port 11, the flow velocity distribution of the airflow in the guide passage 10 or the pipe 2 is as shown in FIG. As shown in FIG. 2, cleaning is faster near the outer periphery than inside, and the cleaning effect on the inner wall surface of the pipe 2 that comes into contact therewith can be enhanced.

In addition, since the piping 2 is cleaned using high-speed airflow, the amount of liquid discharged from the other end of the piping 2 can be kept to a small amount, reducing the amount of waste liquid to be treated compared to conventional cleaning methods that flow liquid. It is possible to downsize the equipment necessary for processing and improve workability.

Furthermore, since a sufficient cleaning effect can be obtained with high-speed airflow, the Coanda type cleaning nozzle 1 itself can be made smaller, and it can be used even in pipes 2, etc. that open into narrow parts where conventional large cleaning nozzles could not be inserted. It is applicable and can dramatically improve workability.

Further, the Coanda type cleaning nozzle 1 of this embodiment is as follows:
Since the connection is made by a connecting member 40 etc. that engages with the flange 2A of the pipe 2, it is easy to handle, and as airflow flows into the pipe 2, adsorption due to the difference in internal and external pressure between the pipe 2 and the discharge port 12 occurs. Since this effect is produced, there is no need for strong mounting or installation of sealing material, durability can be increased, and the structure can be simplified.

Furthermore, in cases where it is inconvenient if cleaning liquid or moisture remains in the piping 2, such as piping for powder or granular materials, by sending high-speed airflow into the piping 2 with the cleaning liquid supply valve 51 closed after cleaning, 2, the time required for cleaning work can be reduced, and the time required for stopping the original use of the piping 2 for cleaning can be shortened.

A second embodiment of the invention is shown in FIG.

In FIG. 3, the Coanda type cleaning nozzle 5 of the present embodiment is smaller than the first embodiment, but includes a substantially similar flow guide passage 10, an injection port 20, a Coanda surface 30, and a cleaning liquid supply pipe 50, Connecting member 4
Although 0 is omitted, it is configured to include a grip part 60 that can be held and operated by an operator.

Here, the grip part 60 is provided with a compressed air passage 61 whose one end is communicated with the pressure accumulation tank 21, and the other end of the compressed air passage 61, which is exposed on the bottom surface of the grip part 60, is connected to the compressed air supply means 3. and is provided with a switching valve 62 in the middle. This switching valve 62 is connected to a trigger lever 63 provided on the front surface of the gripping part 60, and is brought into a conductive state by a worker who grips the gripping part 60 and pulls the trigger lever 62 with a finger 6, etc. to supply compressed air. Means 3
The compressed air is sent to the pressure accumulation tank 21 and injected from the injection port 20.

Further, a door 63 that can be opened and closed is provided on the rear side of the grip portion 60, and a cleaning liquid container 64 containing cleaning liquid is removably housed in the space inside the door 63. The cleaning liquid container 64 has a stopper 65 at the upper end, and the base end side of the cleaning liquid supply pipe 50 passes through the stopper 65 . The cleaning liquid supply pipe 50 is connected to a weight 67 that always moves downward by gravity through a flexible tube 66 inside the cleaning liquid container 64, and is capable of sucking up cleaning liquid from a hole 67A opened in the weight 67. There is. Note that the stopper 65 has a pressure equalizing hole 65A that allows ventilation between the inside and outside of the cleaning liquid container 64.
is provided, so that the cleaning liquid container 64 is protected from changes in internal pressure due to increases and decreases in the cleaning liquid inside.

On the other hand, the guide passage 10 includes a discharge pipe 13 that is continuous with the Coanda surface 30, and a discharge port 12 is formed at the tip thereof. The distance is set to be sufficient for the cleaning liquid to diffuse into the discharge pipe 13 and be sufficiently mixed. In addition, the suction port 11 of the flow guide passage 10
A duct 14 formed in a substantially ragged shape is attached to the duct 14 so that outside air can be efficiently sucked in.

In this embodiment configured in this way, the operator holds the grip part 60 and inserts the discharge pipe 13 into the pipe 2 to be cleaned, or points the discharge port 12 at an object such as a wall and triggers the discharge pipe with a finger. By pulling the lever 62, high-speed airflow is jetted to perform cleaning. At this time, the cleaning liquid in the cleaning liquid container 64 is sucked out with the generation of airflow in the flow guide passage 10 and sprayed in the form of a mist along with the airflow. However, if the cleaning liquid in the cleaning liquid container 64 runs out, the door 63 is closed. The cleaning liquid container 64 is opened and the cleaning liquid container 64 is taken out and the cleaning liquid is refilled or replaced with another cleaning liquid container 64.

According to this embodiment, in addition to obtaining substantially the same effects as in the previous embodiment, cleaning can be easily performed by grasping and operating the grip portion 60, which is useful when cleaning complicated mechanical devices, etc. However, it can work extremely efficiently.

Also, the cleaning liquid is transferred to the cleaning liquid container 64 in the grip part 60.
Since it is housed inside, pipes and the like for supplying cleaning liquid can be omitted, simplifying the structure and making handling easier, improving workability.

Further, the mist cleaning liquid supplied into the flow guide passage 10 is sufficiently diffused and mixed in the discharge pipe 13 and then is injected from the discharge port 12.
It can demonstrate sufficient cleaning power even on objects at close range.

In addition, as the compressed air supply means 3, since the required flow rate of compressed air is small, it is sufficient to use a household compressor for dispersing chemicals, an air pump for automobiles or bicycles, etc. It is possible to reduce

In each of the embodiments described above, the length and diameter of the flow guide passage 10, the position of the opening 52 of the cleaning liquid supply pipe 50, etc. may be changed as appropriate in implementation.

Further, it is not essential to the present invention that the flow guide passage 10 has a substantially circular cross section and that the injection port 20, the pressure accumulator tank 21, etc. are formed in an annular shape; they may have other shapes, and the pressure accumulator tank 21 and Pressure weir 24
Providing is not essential to the present invention, and can be changed or omitted as appropriate.

Furthermore, in the second embodiment, the grip part 60,
The material, shape, etc. of the trigger lever 62 and the like are not limited to those in the second embodiment, and instead of the removable cleaning liquid container 64, the cleaning liquid may be stored in a cavity formed in the grip part 60. .

〔Effect of the invention〕

As described above, according to the Coanda type cleaning nozzle of the present invention, safety and workability can be improved, the structure can be simplified, and highly efficient cleaning can be realized.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a first embodiment of the present invention;
Figure 2 is a perspective view showing the main parts of the first embodiment;
The figure is a sectional view showing a second embodiment of the invention. DESCRIPTION OF SYMBOLS 1, 5... Coanda type cleaning nozzle, 2... Piping which is an object to be cleaned, 3... Compressed air supply means, 4... Cleaning liquid supply means, 10... Direction passage, 11... Inlet, 12
...Discharge port, 13...Discharge pipe, 20...Injection port, 30...
Coanda surface, 40...Connecting member, 50, 52...Cleaning liquid supply pipe and opening, 60...Gripping part, 61...Compressed air supply pipe, 62...Switching valve, 63...Trigger lever, 64...Cleaning liquid container.

Claims (1)

[Claims] 1. A diversion passage having an inlet and a discharge port in the main body, and a diversion passage formed in the circumferential direction of the diversion passage to inject compressed air supplied from the outside into the diversion passage in the radial direction. a possible injection port, and a Coanda surface that bulges out continuously from the inner wall surface of the injection port into the guide passage, is smoothly curved to have an approximately arcuate cross section, and is continuous with the inner wall surface on the discharge port side of the guide passage. and a cleaning liquid supply pipe that opens approximately at the center of the guiding passage surrounded by the Coanda surface and is capable of supplying cleaning liquid into the guiding passage,
The jet of compressed air from the injection port is deflected toward the discharge port by the Coanda effect on the Coanda surface, and a flow from the suction port to the discharge port is formed in the guide passage, thereby sucking the cleaning liquid from the cleaning liquid supply pipe. A Coanda type cleaning nozzle characterized in that it is configured to discharge the water into a mist form from a discharge port. 2. In claim 1, the main body is provided with a connecting member on the outlet side thereof, which is attached to the end opening of the tubular object to be cleaned and connects the flow guide passage to the pipe line of the object to be cleaned. A Coanda type cleaning nozzle characterized by: 3. In claim 1 or 2, the guide passage has a discharge pipe extending toward the discharge port side of the main body, and the main body has a gripping portion, and the gripping portion includes: A cleaning liquid container that stores cleaning liquid to be supplied to the cleaning liquid supply pipe, and a switching valve that can be operated by a trigger lever formed on the grip and that can connect and disconnect the compressed air supply pipe that supplies compressed air to the injection port from the outside. A Coanda type cleaning nozzle characterized by being provided with.