JP6619037B2 - Blasting equipment - Google Patents

Description

  The present invention relates to a blasting apparatus for performing a finishing process on a workpiece surface by injecting abrasive grains with compressed air.

  For metal materials such as steel, which are widely used in construction and facilities, stainless steel is selected for applications that require corrosion resistance. Stainless steel is a hot rolled material with no gloss depending on the surface finish. No. 1 material or a slightly rolled gloss with cold rolled material. It is classified as 2B material, etc., and is properly used according to the application.

  Various metal materials such as stainless steel are easily scratched on the surface during transportation and assembly, and masking or cover mounting may be required depending on the appearance requirements. In addition, when welding is performed, welding marks remain at the joints. These scratches and weld marks are repaired in appearance such as grinding with a grinder or smoothing the surface with buffing.

  Grinding, buffing, etc. are finishing methods that prepare a metallic surface to produce gloss, but are difficult to apply to non-glossy surfaces. As a finishing method that can be used on a non-glossy surface of a metal material, Patent Literature 1 discloses an abrasive grain firing device that performs fine surface blasting by injecting fine abrasive grains onto a workpiece by compressed air. Yes.

JP 2006-192559 A

  A blasting apparatus such as that disclosed in Patent Document 1 can be applied to a wide variety of surface finishes from various materials and non-glossy surfaces to glossy surfaces by appropriately combining the hardness, particle size, injection pressure, and the like of the abrasive grains. However, since it is not easy to take measures against scattering around the abrasive grains and recovery, it is usually performed in a factory equipped with a processing booth. Therefore, due to the size of the apparatus and the necessary cost, there is a problem that it is difficult to operate in a work site where a large facility cannot be installed.

  In addition, surface finishing by grinders and buffing that can be performed at the work site can be applied to glossy surfaces. When applied to a non-glossy surface such as one material, there is a problem that the appearance may rather be impaired.

  The present invention has been made to solve the above-described problems of the prior art, and an object thereof is to provide a blasting apparatus capable of performing various surface treatments with a small and inexpensive apparatus that can be constructed at a work site. .

  The blasting apparatus of the present invention is connected to the suction pipe through an abrasive grain storage tank for storing abrasive grains, a suction pipe for sucking the abrasive grains from the abrasive grain storage tank, and a first pipe having flexibility. And a jet nozzle that sprays the abrasive grains onto the workpiece by compressed air supplied by a flexible second pipe, and a elasticity that covers the machining area of the workpiece and is attached to the tip of the jet nozzle A skirt portion having an inner diameter of the injection nozzle, the abrasive grains sprayed onto the workpiece, an abrasive grain return portion for deriving the compressed air, and a third pipe having flexibility. A powder separation unit connected to the abrasive grain return part, allowing the abrasive grains and the compressed air to flow in from the tangential direction of the funnel-shaped inner wall, and centrifuging the abrasive grains and the air by a spiral airflow by vortex rotation; The upper part of the powder separation part and the center of the vortex rotation The centrifugally separated abrasive grains fall into the abrasive grain storage tank disposed at the lower part of the powder separation part, and the abrasive grain storage tank is disposed at the lower part of the powder separation part. An upper lid to be connected, a side wall in contact with an upper edge of the upper lid, and a bottom part in contact with a lower part of the side wall and having at least one surface having an angle of more than 90 degrees with the side wall.

  According to the present invention, due to the venturi effect of the compressed air supplied to the spray nozzle by the second pipe, the inside of the first pipe becomes negative pressure, and the abrasive grains are sucked from the abrasive grain storage tank through the suction pipe and processed. It is jetted at high speed. The abrasive is sent to the powder separation part through the third tube from the abrasive return part provided inside the injection nozzle together with the compressed air without scattering to the outside by the elastic skirt attached to the tip of the injection nozzle. The Centrifugation due to the specific gravity difference between the abrasive grains and the air is performed by causing the abrasive grains and the compressed air to flow from the tangential direction of the funnel-shaped inner wall of the powder separator and swirl.

  Air is exhausted from an exhaust port provided at the upper part of the powder separation unit and at the center of the vortex rotation, and the abrasive grains fall into an abrasive grain storage tank disposed at the lower part of the powder separation unit. The abrasive grain storage tank is composed of an upper lid, a side wall, and a bottom part, and the bottom part is configured to have at least one surface whose angle with the side wall exceeds 90 degrees, so that the dropped abrasive grains are piled up only at the center of the bottom part. This can prevent the amount of abrasive grains required for stable supply of abrasive grains. Due to the structure of such a blasting device, even if it is a small device, abrasive grains do not scatter, so there is no need for a processing booth, and it is economical because the amount of abrasive grains required is small, and it operates only by supplying compressed air. Therefore, blasting at the work site can be easily performed.

  In the blasting apparatus of the present invention, the abrasive grain storage tank combines a plurality of bottom plates having different angles formed by the four side walls forming a quadrangle when viewed from the axial direction of the vortex rotation and the side walls. The bottom part having the largest distance between the top lid and the bottom part is arranged at a position spaced apart from the center part of the vortex rotation, and the dropped abrasive grains are placed on the bottom part. In order to gather at the bottom, it may have a slope that continues from the side wall, and the suction pipe may be arranged in the vicinity of the bottom.

  Even if, for example, a cylindrical container having a flat bottom is used as the abrasive grain storage tank, the blasting apparatus of the present invention can be configured. However, when using abrasive grains with a wide particle size distribution or mixing abrasive grains of different materials, the properties of the abrasive grains falling from the powder separator are not uniform, and the bottom of the abrasive reservoir There is a possibility that the grain size and the material are uneven in the upper part. In the abrasive grain storage tank of the present invention, the abrasive grains dropped from the powder separation part are mixed again in the process of collapsing toward the bottom or sliding down a plurality of bottom plates having different angles with the side walls and the side walls. Therefore, even if abrasive grains having a wide particle size distribution or abrasive grains of different materials are mixed and used, uniform and stable blasting can be performed.

  Further, in the blasting apparatus of the present invention, an air amplifier suction side that increases a fluid delivery amount by the Coanda effect is arranged at the exhaust port, and a dust collecting filter is arranged on the air amplifier delivery side. good.

  An air amplifier can draw a lot of ambient air using a small amount of compressed air and generate a large amount of air flow, so it can be arranged at the exhaust port of the blasting device to assist the exhaust operation with negative pressure. It becomes possible to improve the efficiency of powder separation. The air amplifier can also be operated only by supplying compressed air. In addition, the exhaust gas may contain a small amount of fine abrasive particles or abrasive powder of a processed product, and dust may be scattered when released to the atmosphere. If an exhaust system equipped with a dust collector is installed, an exhaust port may be connected to the exhaust system. However, if the dust filter is installed directly on the blast device, the convenience of field work can be further enhanced.

  According to the present invention, it is possible to provide a blasting apparatus capable of performing various surface treatments with a small apparatus that can be constructed at a work site.

It is an external view which shows embodiment of the blasting apparatus by this invention. It is a cross-sectional schematic diagram which shows the structure of the powder separation part and abrasive grain storage tank in embodiment of the blasting apparatus by this invention. It is an external view which shows the process part in embodiment of the blasting apparatus by this invention. It is a cross-sectional schematic diagram which shows the structure of the process part in embodiment of the blasting apparatus by this invention. It is an external view which shows the structure of the abrasive grain storage tank in embodiment of the blasting apparatus by this invention, (a) is the side wall and bottom part seen from the upper side of the abrasive grain storage tank, (b) is an abrasive grain storage tank. The bottom and legs as seen from below. It is an external view which shows the shape and arrangement | positioning of a powder separation part, a suction pipe, and an abrasive grain storage tank in embodiment of the blasting apparatus by this invention, (a) was seen from A direction of Fig.5 (a). External view, (b) is an external view seen from direction B in FIG. 5 (a), (c) is an external view seen from direction C in FIG. 5 (a), and (d) is D in FIG. 5 (a). It is the external view seen from the direction.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is an external view showing an embodiment of a blasting apparatus according to the present invention. It is preferable to mount the abrasive grain storage tank 10 on the movable carriage 16 or the like because portability is increased. A powder separation unit 80 and an exhaust port 90 are disposed on the upper lid 11 of the abrasive grain storage tank 10, and an air amplifier 91 and a dust collection filter 92 can be attached to the exhaust port 90 if necessary.

  Further, the upper lid 11 is provided with a suction pipe 12 at a position separated from the powder separation unit 80, and the suction pipe 12 extends to the vicinity of the bottom of the abrasive grain storage tank 10 within a range that does not interfere with the suction of the abrasive grains. One end of the first pipe 20 that conveys the sucked abrasive grains is connected to the suction pipe 12, and the other end of the first pipe 20 is connected to the injection nozzle 50.

  Compressed air is supplied to the injection nozzle 50 through the second pipe 30. Since the required air pressure and flow rate differ depending on the blasting conditions, it is preferable to adjust appropriately using a regulator, a flow controller, or the like. Further, if the processing amount is small, it can be supplied by a compressed air cylinder.

  A skirt portion 60 having elasticity for suppressing the scattering of abrasive grains and facilitating recovery is attached to the tip of the injection nozzle 50, and an abrasive grain return portion (not shown) is disposed inside the injection nozzle 50. . One end of the third tube 40 is connected to the abrasive grain return portion, and the other end of the third tube 40 is connected to an opening (not shown) in the upper part of the powder separation unit 80.

  When abrasive grains are put in the abrasive reservoir 10 and compressed air is supplied from the second pipe 30 to the injection nozzle 50, the first pipe 20 becomes negative pressure and sucks the abrasive grains from the suction pipe 12, thereby causing high-speed and high-pressure. Is injected onto the surface of the workpiece together with the air. At this time, if the skirt portion 60 is kept in close contact with the surface of the workpiece, the abrasive grains will not scatter around and the abrasive grains are removed from the abrasive return portion using the pressure of the compressed air. 40. The abrasive grains introduced from the third tube 40 into the powder separation unit 80 are separated from the air by centrifugation, the air is exhausted from the exhaust port 90, and the abrasive grains pass through the funnel-shaped inner wall of the powder separation unit 80. The processing cycle of the blasting apparatus of the present invention can be smoothly performed by descending and dropping into the abrasive grain storage tank 10.

  FIG. 2 is a schematic cross-sectional view showing the configuration of the powder separation unit and the abrasive grain storage tank in the embodiment of the blasting apparatus according to the present invention.

  Compressed air and abrasive grains conveyed by the third tube 40 are introduced into the opening 81 at the top of the powder separation unit 80. The opening 81 is arranged so that a stream of compressed air containing abrasive grains flows in from the tangential direction of the funnel-shaped inner wall of the powder separation unit 80 to cause vortex rotation. When the flow velocity of the inflowing air is slow, the abrasive grains may stay in front of the opening 81 or the small diameter abrasive grains may not be separated and may be discharged to the exhaust port 90 side.

  As a means for increasing the flow velocity of the airflow flowing into the powder separation unit 80, it is also effective to provide a throttle part (not shown) that makes the sectional area of the opening 81 smaller than the sectional area of the third tube 40. However, since the pressure loss increases when the flow velocity of the airflow is too high, in a small apparatus intended for on-site construction, the pressure is adjusted using the regulator 82 or the flow rate is adjusted using the flow controller, depending on the processing conditions. It is desirable to set the optimal flow rate.

  The abrasive grains separated by the powder separation unit 80 fall into the abrasive grain storage tank 10. At this time, the bottom portion 14 of the abrasive grain storage tank 10 can be used even if it is flat, but it is preferable to provide at least one surface having an angle of more than 90 degrees with the side wall 13 for the following reason. The bottom portion 14 is formed by combining a plurality of bottom plates that are quadrangular when viewed from the axial direction and are combined with a plurality of bottom plates that are different in angle with the side wall 13, and the bottom portion is arranged at a position separated from the center portion of the vortex rotation. More preferably, the tube is arranged in the vicinity of the bottom.

  That is, since the dropped abrasive grains accumulate in a conical shape, it is necessary to arrange the suction port of the suction pipe 12 directly below the position where the abrasive grains fall from the powder separation unit 80, which is not rational in terms of equipment design. . When the suction pipe 12 is disposed at the end of the abrasive grain storage tank 10, the abrasive grain accumulation height inside the abrasive grain storage tank 10 is a relatively low place. In this case, it is necessary to keep more than the necessary amount of abrasive grains, which is not preferable because of extra cost. In addition, when using abrasive grains having a wide particle size distribution or abrasive grains of different materials, there is a possibility that the grain size and the material may be biased between the bottom side and the top side of the abrasive grain storage tank 10.

  If the bottom part 14 of the abrasive grain storage tank 10 has at least one surface exceeding 90 degrees with respect to the side wall 13, the angle formed by the side wall 13 and the side wall 13 with the abrasive grains falling from the powder separation unit 80 A plurality of bottom plates, which are different from each other, are crushed toward the bottom or mixed again in the process of sliding down, so even if abrasive grains with a wide particle size distribution or abrasive grains of different materials are mixed and used, uniform and stable blasting It can be performed.

  FIG. 3 is an external view showing a processing unit in the embodiment of the blasting apparatus according to the present invention. The injection nozzle 50 includes a first pipe 20 for supplying abrasive grains, a second pipe 30 for supplying compressed air, abrasive grains containing a small amount of abrasive powder from the workpiece, and an abrasive return for collecting compressed air. A third pipe 40 connected to a portion (not shown) is connected, and a skirt portion 60 made of a material having elasticity such as rubber is attached to a portion of the injection nozzle 50 that comes into contact with the workpiece.

  FIG. 4 is a schematic cross-sectional view showing the configuration of the processing unit in the embodiment of the blasting apparatus according to the present invention, and more specifically describes the configuration of FIG.

  The flow rate of the compressed air supplied by the second pipe 30 increases as it passes through the throttle portion 31, and the first pipe 20 becomes negative pressure by the venturi effect to suck up the abrasive grains. A high-speed and high-pressure air stream containing abrasive grains is jetted onto the workpiece 100 to polish the surface. Depending on the grain size and type of abrasive grains, jetting strength, etc., the surface of the workpiece 100 can be made a rough surface with no gloss or can be finished to a glossy surface.

  In the conventional blasting apparatus, since the sprayed abrasive particles scatter around, it is necessary to perform the construction in a processing booth equipped with a dust collection facility. However, in the blasting apparatus of the present invention, the processing object 100 of the injection nozzle 50 is required. An elastic skirt portion 60 is attached to the portion in contact with the nozzle, and an abrasive grain return portion 70 for connecting the third tube 40 to the spray nozzle 50 is provided, and the processed abrasive grains and compressed air are collected to separate the powder. Send to the department.

  FIG. 5 is an external view showing a configuration of an abrasive grain storage tank in an embodiment of a blasting apparatus according to the present invention, (a) is a side wall and a bottom part as viewed from the upper side of the abrasive grain storage tank, and (b) is an abrasive. It is the bottom part and leg part which were seen from the grain storage tank lower side. Although the abrasive grain storage tank of FIG. 5 exemplifies a quadrangular shape formed by the four side walls 13 for ease of manufacture, it may be a hexagonal shape, an octagonal shape, a cylindrical shape, or the like. In FIG. 5, the bottom 14 surrounded by the four side walls 13 is formed by combining a trapezoidal shape and a triangular bottom plate so that the angles formed with the respective side walls are different. The arrows in FIG. 5A indicate that the side wall 13 described in FIG. 6 is viewed from directions A, B, C, and D.

  FIG. 6 is an external view showing the shape and arrangement of the powder separation unit, the suction pipe, and the abrasive grain storage tank in the embodiment of the blasting apparatus according to the present invention, (a) direction A in FIG. 5 (a) (B) External view viewed from direction B in FIG. 5 (a), (c) External view viewed from direction C in FIG. 5 (a), (d) D in FIG. 5 (a). It is the external view seen from the direction.

  The shape of the bottom part 14 provided with one or more surfaces where the angle formed with the side wall 13 exceeds 90 degrees and the side wall 13 having different shapes along the bottom part 14 is shown. In order to support the inclined part of the bottom part 14 and to make the blasting apparatus stand upright, it is preferable to attach the leg part 15. Further, the suction pipe 12 is preferably disposed in the vicinity of the bottom of the bottom 14.

  As mentioned above, although the Example of this invention was described, this invention is not limited to the structure of Embodiment, A change and correction of a structure are possible in the range which does not deviate from the summary of this invention. That is, various changes and modifications that can be made by those skilled in the art are also included in the present invention.

DESCRIPTION OF SYMBOLS 10 Abrasive grain storage tank 11 Top cover 12 Suction pipe 13 Side wall 14 Bottom part 15 Leg part 16 Movable carriage 20 First pipe 30 Second pipe 31 Restriction part 40 Third pipe 50 Injection nozzle 60 Skirt part 70 Abrasive return part 80 Powder separation part 81 Opening part 82 Regulator 90 Exhaust port 91 Air amplifier 92 Dust collection filter 100 Object to be processed

Claims (2)

An abrasive reservoir for containing abrasive grains;
A suction pipe for sucking the abrasive grains from the abrasive grain storage tank;
An injection nozzle that is connected to the suction pipe via a first pipe having flexibility, and that injects the abrasive grains onto the workpiece by compressed air supplied by the second pipe having flexibility;
A skirt having elasticity to cover the processing region of the processing object and attach to the tip of the spray nozzle;
An abrasive grain return portion for deriving the abrasive grains and the compressed air, which are provided inside the jet nozzle and jetted onto the workpiece;
The abrasive grains are connected to the abrasive grain return portion via a third tube having flexibility, and the abrasive grains and the compressed air are caused to flow in from a tangential direction of the funnel-shaped inner wall, and the abrasive grains are caused by a spiral airflow caused by vortex rotation. And a powder separation part for centrifuging the air,
An exhaust port provided at the upper part of the powder separation unit and at the center of the vortex rotation;
The centrifuged abrasive grains fall into the abrasive grain storage tank disposed at the lower part of the powder separation unit,
The abrasive grain storage tank includes an upper lid connected to a lower portion of the powder separation unit, four side walls that contact an upper edge of the upper lid and form a quadrangle when viewed from the axial direction of the vortex rotation, and the side walls bottom to contact the angle formed between the side wall is greater than 90 degrees, and has the bottom formed by integrating a combination of a plurality of bottom plate made of a different angle, the largest distance between the upper lid and the bottom part The bottom is disposed at a position spaced apart from the center of the vortex rotation, the bottom includes an inclination that continues from the side wall so that the dropped abrasive grains gather at the bottom, and the suction pipe A blasting device arranged near the bottom.   The exhaust port is provided with a suction side of an air amplifier that increases the amount of fluid delivered by the Coanda effect, and a dust collection filter is provided on the delivery side of the air amplifier. Blasting equipment.