WO2015059941A1

WO2015059941A1 - Blast machining method and blast machining device

Info

Publication number: WO2015059941A1
Application number: PCT/JP2014/058044
Authority: WO
Inventors: 間瀬　恵二; 克幸佐久間
Original assignee: 株式会社不二製作所
Priority date: 2013-10-21
Filing date: 2014-03-24
Publication date: 2015-04-30
Also published as: CN105636745B; KR20160073983A; EP3061567B1; EP3061567A1; US20160236323A1; CN105636745A; JP6452615B2; KR101847316B1; JPWO2015060043A1; EP3061567A4; WO2015060043A1

Abstract

Provided is a blast machining method in which static electricity-preventing effects coexist with processed volume-increasing effects. A liquid such as water is introduced in relatively small volumes of 0.06 cc/min - 150 cc/min to a blast nozzle (8) provided in a blast machining device. The introduced liquid is atomized by causing the liquid to collide with a high speed compressed gas stream flowing inside the blast nozzle (8) or a high speed compressed gas stream jetted from the blast nozzle (8). The atomized liquid is jetted towards the workpiece (W) along with the compressed gas and an abrasive. As a result of the jetted liquid evaporating easily because the liquid is atomized and jetted in this manner and the volume of liquid supplied is relatively small, humidity inside the work chamber increases and generation of static electricity is limited. Additionally, the workpiece is cooled by vaporization heat being consumed during evaporation and absorption of the impact energy of the abrasive that occurs as a result of the softening of the workpiece surface due to heat generated by collision with the abrasive is limited and processed volume (cut volume) is improved.

Description

Blasting method and blasting apparatus

The present invention relates to a blasting method for injecting an abrasive together with a compressed gas to perform cutting of a workpiece, surface polishing, deburring, coating film removal, and the like, and a blasting apparatus used for the blasting method.

Blasting, which processes the workpiece using the cutting force exerted when the abrasive material injected with the compressed gas collides with the workpiece, includes cutting, surface polishing, surface polishing, deburring, and coating. Widely used in various applications such as removal of membranes and removal of dirt such as rust.

In such blasting, when abrasive material is injected together with compressed gas onto the work piece, static electricity is generated due to the friction caused by the collision with the work piece or the inner wall of the cabinet as the work space. Abrasive material or cutting powder generated by cutting the workpiece adheres to the inner wall of the workpiece, cabinet, and other inner walls of ducts, cyclones, abrasive tanks, etc. that constitute the abrasive circulation system As a result, the abrasive cannot be collected and supplied smoothly.

In particular, as the demand for microfabrication by blasting increases, the use of abrasives has increased, and as a result, abrasives are more likely to adhere to workpieces and cabinet inner walls due to static electricity. The adhered abrasive is difficult to remove completely by air blow or the like, and it is necessary to provide a cleaning process for removing the abrasive adhered to the workpiece after blasting. It is also a factor.

In order to prevent such adhesion of abrasives due to static electricity, it is conceivable to equip the blasting device with a voltage application type static eliminator (“ion generator”).

However, if equipped with such an expensive device, not only will it increase the price of the blasting machine and lose price competitiveness in the market, but it is also installed in the ion generator to generate ions Electrode needles are easily soiled, require frequent maintenance, and static electricity remains where the abrasive is peeled off due to charge removal (neutralization) with the abrasive adhered to the object to be treated.

Furthermore, since corona discharge is performed to generate ions, it can be an ignition source in dust explosions and the like, so the ion generator is structurally unsuitable for use in blasting equipment.

Therefore, in order to solve such problems caused by static electricity, it has been proposed to remove static electricity by applying moisture to the working space and the circulation path of the abrasive.

As an example of such a method, by introducing a compressed gas that has been given moisture by a humidifying means to an abrasive jet nozzle, the humidity in the circulating system of the abrasive is adjusted to prevent the generation of static electricity. It has been proposed (see Patent Document 1 [0011] column, FIG. 2).

It has also been proposed to supply moisture to the compressed gas introduced into the abrasive jet nozzle in this way in the form of water vapor using an ultrasonic heater or heating (Patent Document 2 [0026]). Column).

As a blast nozzle used for wet blasting for the purpose of preventing the generation of dust, compressed gas, abrasive (media) and water are mixed in approximately equal amounts by weight in a chamber formed inside. A blast nozzle that injects a three-phase flow of gas, liquid, and solid (abrasive material) has also been proposed (see Patent Document 3, [0006], FIG. 1, FIG. 2, and Table 1 [3]).

Japanese Patent No. 3846842 Japanese Unexamined Patent Publication No. 2011-237378 Japanese Unexamined Patent Publication No. 2006-297568

Among the conventional techniques described above, the blasting method using the nozzle described in Patent Document 3 is a method in which a large amount of water of 160 to 200 cc / min is injected (Patent Document 3, Table 1 [2] [3] ], A kind of wet blasting method generally called “wet blasting” or “liquid honing”.

When the workpiece is processed by such a wet blasting method, the surface of the workpiece is wetted by the sprayed water, so that generation of static electricity can be reduced.

However, when a workpiece is processed by such a wet blasting method, the surface of the workpiece is surely wetted. It cannot be applied to the work piece, and there is a case where the work piece needs to be washed or dried after the work, and these operations contribute to a decrease in productivity.

In addition, in such a wet blasting method in which the abrasive is sprayed with a large amount of water, the collision energy when the abrasive collides with the surface of the workpiece is absorbed by the presence of water sprayed with the abrasive. Therefore, wet blasting has a lower processing amount (cutting speed) than dry blasting, and the conditions such as abrasive material used, particle size, and injection pressure are the same. In some cases, the amount of machining (cutting amount) decreases to about 1/7 to 1/14 in wet blasting compared to dry blasting.

As an example, FIGS. 23 and 24 show the measurement of the difference in coverage between dry blasting and wet blasting. Both dry and wet abrasives are alumina-based abrasives ("Fuji Random WA" manufactured by Fuji Seisakusho). # 1000) and a 150 mm square glass plate was processed at an injection pressure of 0.3 MPa.

FIG. 23 shows a change in processing time until the coverage becomes 100% with respect to a change in the distance between the tip of the blast nozzle and the workpiece (nozzle distance), and FIG. 24 shows a coverage with respect to a change in the particle size of the abrasive. The change in the processing time is displayed, and it can be seen that the processing time for obtaining 100% coverage is longer in wet blasting than in dry blasting under any conditions. .

Here, “coverage” is the ratio of the total indentation area to the processing area expressed in%, and the amount of processing can be predicted by the size of the coverage. Therefore, from FIG. 23 and FIG. Then, it turns out that it is inferior in the amount of processing (cutting speed) compared with dry blasting.

In contrast to wet blasting as described above, the blasting method described in Patent Document 1 described above increases the humidity in the cabinet, which is the work space, by adding moisture to the compressed gas that injects the abrasive. This prevents the generation of static electricity and the adhesion of abrasives to the workpiece surface and cabinet inner surface due to static electricity.

However, in the blast processing apparatus described in Patent Document 1, water is added to the compressed air flowing in the compressed air supply pipe provided between the compressed air supply source and the blast nozzle. The compressed air flowing through the air supply pipe has a slower flow velocity than the compressed air flowing through the small diameter flow path in the blast nozzle. Therefore, even if water is introduced into the compressed air introduction pipe, Is introduced into the blast nozzle in a liquid state without being sprayed due to collision with the compressed air flow, causing clogging of the blast nozzle by agglomerating the abrasive and causing blast processing. The device will not work properly.

Therefore, Patent Document 1 does not include a detailed description of the water addition method, but when water is added to the compressed air flowing in the compressed air introduction pipe, such a malfunction due to clogging does not occur. As described in Patent Document 2, it is necessary to add water to the compressed gas in the form of water vapor by a method such as ultrasonic wave or heating, and thus has a function to turn water into water vapor. It is necessary to provide a moisture providing mechanism separately, which makes the apparatus configuration complicated and expensive.

As described above, in the methods described in

Patent Documents

1 and 2, although moisture is added to the compressed gas before being introduced into the blast nozzle, the moisture is added in the state of water vapor (gas). The fluid ejected from the nozzle does not contain “liquid”. Therefore, the inventions described in

Patent Documents

1 and 2 are maintained to be “dry” blasting even by adding water.

Therefore, the methods described in

Patent Documents

1 and 2 can perform processing without wetting the surface of the workpiece, and can be applied to a workpiece that dislikes contact with water. There is an advantage that the processing amount (cutting speed) is larger than blast processing.

However, in the blasting methods described in

Patent Documents

1 and 2, if the amount of water to be supplied is small and the processing chamber cannot be sufficiently humidified, the generation of static electricity cannot be sufficiently prevented, but saturation occurs. Supplying water that exceeds the amount of water vapor will cause condensation in the work space and wet the surface of the workpiece or the inner wall of the cabinet, preventing the generation of static electricity but losing the benefits of dry blasting.

Therefore, in the blasting method described in Patent Document 1, the humidity in the processing chamber is detected, the necessary amount of moisture is calculated and moisture is supplied, and the control is extremely complicated. Complicated and expensive.

As described above, the inventions described in

Patent Documents

1 and 2 maintain dry blasting, and thus maintain a large machining amount (high cutting speed) compared to wet blasting, while maintaining static electricity. However, in order to do so, it is necessary to adopt a special device configuration and to perform complicated control.

On the other hand, as described in Patent Document 3, in wet blasting, the generation of static electricity can be greatly reduced without complicated control by a relatively simple device configuration, but the workpiece In addition to reducing the productivity, the addition of these processes not only reduces the productivity but also reduces the amount of processing (cutting) compared to dry blasting. In this respect, workability and productivity are greatly inferior, and there are advantages and disadvantages in adopting either method.

In view of the above points, the inventors of the present invention have conducted intensive research aimed at realizing a blasting process capable of preventing the generation of static electricity without sacrificing the processing amount. It is possible to suppress the generation of static electricity by performing atomization just before the nozzle outlet and limiting the amount of water added to a predetermined range that is significantly smaller than that of known wet blasting. Rather, it was found that the machining amount can be greatly improved.

Moreover, the increase in the processing amount obtained by this processing method is not only increased in comparison with wet blasting, but also surprisingly greatly improved in comparison with dry blasting. At the same time, it has been confirmed that not only the processing amount is improved, but also various other effects which cannot be expected from Patent Document 1 can be obtained in a superimposed manner.

The present invention was made on the basis of the above findings obtained by the inventors as a result of earnest research, and can be applied to the existing dry-type blasting machine with a slight structural change. An object of the present invention is to provide a blasting method and a blasting apparatus that can not only prevent the occurrence of the above-described problem but also improve the processing amount (cutting speed) in comparison with dry blasting as well as conventional wet blasting.

Hereinafter, means for solving the problem will be described together with reference numerals used in the embodiment for carrying out the invention. This code is used to clarify the correspondence between the description of the scope of claims and the description of the mode for carrying out the invention. Needless to say, it is used in a limited manner for the interpretation of the technical scope of the present invention. It is not a thing.

In order to achieve the above object, the blasting method of the present invention comprises:
In a blasting method for injecting an abrasive together with a compressed gas through a blast nozzle 8 to a workpiece,
A liquid such as water is introduced into the blast nozzle 8, and the liquid is made to collide with the compressed gas flowing through the blast nozzle 8 or the compressed gas ejected from the blast nozzle to atomize the atomized liquid. Spraying with the compressed gas and abrasive,
The amount of the liquid introduced into the blast nozzle 8 is set to 0.06 cc / min to 150 cc / min (claim 1).

The above liquids include so-called “water” such as tap water, pure water, purified water, alkaline ionized water, scale remover added for the purpose of removing scale of pure water and hard water, marking of processed parts, etc. It may contain paints, fluorescent paints, etc. added for the purpose.

Moreover, the blasting apparatus 1 of the present invention used for the blasting method described above is:
In a blasting apparatus 1 for injecting a compressed gas flow supplied from a compressed gas supply source (not shown) from a blast nozzle 8 as a mixed fluid with an abrasive,
One end of the blast nozzle 8 can communicate with a liquid supply source (not shown), and the other end is opened in the flow path of the compressed gas in the blast nozzle 8 or in the injection port of the blast nozzle 8. A liquid introduction path 88 is provided for causing the liquid introduced from the liquid supply source to collide with a compressed gas flow flowing through the blast nozzle 8 or a compressed gas flow injected from the blast nozzle 8 to be atomized,
A flow rate control means such as a flow rate adjusting valve 7 or a pump is provided between the liquid introduction path 88 and the liquid supply source (Claim 2).

In the blasting apparatus 1 configured as described above, the blast nozzle 8 includes a nozzle 82 in the jet direction of the jet 83 communicating with the compressed gas supply source, and an abrasive that communicates with the abrasive supply source between the jet 83 and the nozzle 82. A suction chamber including an introduction chamber 85, which generates a negative pressure in the abrasive introduction chamber 85 by injection of a compressed gas flow from the jet 83, sucks the abrasive from the abrasive supply source, and injects it as a mixed fluid; Type blast nozzle,
The other end (tip 88 a) of the liquid introduction path 88 can be configured to open in a compressed gas flow path 86 provided in the jet 83 or at a position in front of the jet port of the jet 83 (invention). 3).

Further, in the blasting apparatus 1 having the above-described configuration, the liquid introduction path 88 is formed by a pipe line that is concentrically inserted into the compressed gas flow path 86 provided in the jet 83. It is good also as a structure which opened the said other end (front-end | tip 88a) in the injection outlet of the said jet 83 (Claim 4).

The blasting apparatus 1 having the above-described configuration may be provided with a liquid constant supply means such as a pump for supplying a constant amount of the liquid from the liquid supply source to the liquid introduction path 88 (Claim 5).

With the configuration of the present invention described above, the following remarkable effects can be obtained according to the blasting method and the blasting apparatus of the present invention.

A liquid such as water collides with the compressed gas flowing through the blast nozzle 8 or the compressed gas injected from the blast nozzle 8, and the amount of liquid introduced into the blast nozzle is 0.06 to 150 cc / min. Therefore, the atomized liquid is reduced between the blast nozzle 8 and the workpiece W due to a pressure drop when sprayed by the blast nozzle 8 and heat generated when the abrasive material collides with the workpiece W. In this space, or in the surface of the workpiece W, the water rapidly evaporates to become water vapor, so that the humidity in the processing chamber 21 can be increased and the generation of static electricity can be prevented.

In addition, despite the prevention of the occurrence of static electricity, the workpiece W is not wetted, or even if the workpiece is wetted, the degree of wetting is less than that of known wet blasting. The blasting method can be applied to workpieces and the like that dislike contact with water by adjusting the water supply conditions, and there is no need to add new steps such as washing and drying after processing.

Furthermore, in the blasting method of the present invention, in addition to the effect of preventing the generation of static electricity as described above, the effect of improving the processing amount (cutting speed) more than that obtained by the known dry blasting method is first mentioned. Prevents abrasive material from sticking to the surface, reduces consumption of abrasive material, improves cutting speed, removal efficiency of coating film, burrs, etc., reduces the elongation and warpage of the workpiece, reduces the temperature rise of the workpiece We were able to obtain new effects beyond expectations, such as reducing the burning of the product.

The reason why such an effect such as an increase in the cutting speed is obtained is not clear, but it is likely that the liquid sprayed in the state of being atomized by the collision with the compressed gas flow is abrupt when it exits the blast nozzle. Micro-mist is further reduced by the pressure drop, and suddenly evaporates in the front space of the work piece or on the surface of the work piece due to contact with the work piece generated by collision with the abrasive. This is considered to be an effect obtained by taking a large amount of heat of vaporization from the surface of the air or workpiece (spray cooling).

That is, considering the improvement of the machining amount (cutting speed) as an example of the effects described above, wet blasting is one of the reasons why the machining amount (cutting speed) is lower than dry blasting. It is considered that water sprayed with the abrasive forms a water film on the surface of the workpiece, and this water film absorbs the collision energy of the abrasive that tries to collide with the surface of the workpiece. It is done.

However, in the method of the present invention, the atomized liquid jetted quickly as it exits the blast nozzle 8 as described above, so that it did not wet the workpiece or wet the surface of the workpiece. However, since the degree of wetting is less than that of known wet blasting, it is possible to maintain the same collision energy as dry blasting, and as a result, a large amount of processing can be maintained even by liquid injection.

On the other hand, in comparison with dry blasting, in dry blasting, the surface temperature of the workpiece rises due to the collision of the abrasive, and this temperature increase softens the surface of the workpiece and absorbs the collision energy of the abrasive. This is thought to contribute to the reduction in cutting speed.

On the other hand, in the method of the present invention, the increase in the surface temperature of the workpiece is suppressed by the above-described spray cooling, and the processing is performed in a state where the surface hardness of the workpiece is maintained. It is considered that the amount of machining (cutting speed) was also improved.

In the blasting method of the present invention described above, the above-described configuration of an existing dry blasting apparatus is replaced with the above-described blast nozzle 8 that enables liquid injection, and liquid is supplied to the blast nozzle 8. This can be realized by a relatively simple structural change such as addition of a flow rate control means such as a flow rate adjusting valve 7 or a pump for controlling the liquid supply source to be performed and the liquid supply amount to the blast nozzle 8.

Further, a pipe inserted concentrically into the compressed gas flow path 86 provided in the jet 83 of the blast nozzle 8 is used as the liquid introduction path 88, and the other end (tip 88a) of the pipe 88 is connected to the jet 83. In the configuration that opens at the injection port, it is possible to introduce the liquid through the liquid introduction path 88 by the negative pressure generated by the injection of the compressed gas from the jet 83. Separately, a liquid such as a pump is used. It is not necessary to provide a means for supplying the liquid, and since the introduction and stop of the liquid are performed in conjunction with the start and stop of the introduction of the compressed gas to the blast nozzle 8, the supply of the liquid is performed. There is no need to provide a separate means for starting and stopping, and the existing equipment can be used by replacing only the jet 83 of the blast nozzle 8.

Of course, a configuration may be adopted in which a constant supply means such as a pump for supplying the liquid from the liquid supply source to the liquid introduction path 88 is provided. In this case, the design of the liquid introduction position with respect to the blast nozzle 8 may be adopted. As the degree of freedom increases, the liquid can be supplied more stably and reliably.

Explanatory drawing which shows the example of 1 structure of the blast processing apparatus of this invention. Sectional drawing of the blast nozzle provided in the blast processing apparatus of this invention. Explanatory drawing of the liquid introduction position with respect to a blast nozzle (suction type). Explanatory drawing of the liquid introduction position with respect to a blast nozzle (direct pressure type). Sectional drawing of another blast nozzle provided in the blast processing apparatus of this invention. The graph which showed the change (boron board) of the processing amount with respect to the change of water supply amount. The graph which showed the change (carbide board) of the processing amount with respect to the change of water supply amount. The graph which showed the change (urethane rubber board) of the processing amount with respect to the change of water supply amount. The graph which showed the change of the amount of processing (aluminum board) with respect to the change of the amount of water supply. The graph which showed the change of the amount of processing (stainless steel board) with respect to the change of the amount of water supply. The graph which showed the change (steel plate) of the processing amount with respect to the change of water supply amount. The graph which showed the change (acrylic board) of the processing amount with respect to the change of water supply amount. The graph which showed the change (epoxy glass board) of the processing amount with respect to the change of water supply amount. The graph which showed the change (granite) of the processing amount with respect to the change of the amount of water supply. The graph which showed the change (urethane rubber) of the amount of piercing of the abrasives with respect to the change of the amount of water supply. The graph which showed the change (stainless steel) of the amount of sticking of an abrasives with respect to the change of the amount of water supply. The graph which showed the change (iron) of the amount of piercing of the abrasives with respect to the change of the amount of water supply. The graph which showed the change (acrylic) of the amount of sticking of an abrasive | polishing material with respect to the change of water supply amount. The graph which showed the change (epoxy glass) of the amount of stabs of the abrasives with respect to the change of the amount of water supply. The photograph which image | photographed the particle structure of the abrasives used by the blasting method (Example) of this invention, and the abrasives used by the dry-type blasting method (comparative example). It is the surface roughness data of the polycarbonate product after peeling the coating film by blasting, (A) is processed by the method of the present application (Example), (B) is processed by dry blasting (Comparative Example) . Data of surface roughness of polyphenylene sanfide product after deburring by blasting, (A) is processed by the method of the present application (Example), (B) is processed by dry blasting (comparison) Example). The correlation diagram which showed the change of time until it becomes 100% of coverage with respect to the change of nozzle distance. The correlation figure which showed the change of time until it becomes 100% of coverage with respect to the particle size change of an abrasives.

Next, embodiments of the present invention will be described below with reference to the accompanying drawings.

1. Blast Processing Device (1) Overall Configuration FIG. 1 shows a configuration example of the blast processing device 1 of the present invention.

As shown in FIG. 1, the blast processing apparatus 1 includes a compressed gas supply source (not shown), an abrasive tank 3 as an abrasive supply source, and a compressed gas introduced from the compressed gas supply source and the abrasive. A blast nozzle 8 is provided for merging and injecting abrasives from the tank 3. In the illustrated embodiment, a blast nozzle is introduced by introducing compressed gas from a compressed gas supply source, in this embodiment, compressed air. 8 is configured as a so-called “suction type” blasting device in which the abrasive material from the abrasive material tank 3 is sucked by the negative pressure generated in the air 8, merged with the compressed gas flow, and injected to the workpiece W. Yes.

In the illustrated embodiment, a processing chamber 21 formed in the cabinet 2 that accommodates the blast nozzle 8 and a hopper formed at the lower end of the processing chamber 21 communicated with each other through an abrasive recovery pipe 91. The above-mentioned abrasive tank 3 that is a cyclone and a dust collector 5 that sucks the inside of the abrasive tank 3 are provided, and the exhaust fan 6 provided in the dust collector 5 is operated to suck the inside of the abrasive tank 3 that is a cyclone. However, when the abrasive is sprayed from the blast nozzle 8 accommodated in the processing chamber 21, the sprayed abrasive is introduced into the abrasive tank 3 through the abrasive recovery pipe 91 together with the cutting powder and the like, and the abrasive tank 3 The reusable abrasive is collected at the bottom of the abrasive tank 3 by the wind sorting inside, and the crushed abrasive and dust are sucked into the dust collector 5 and removed. It is configured, so that it can be recycled abrasive.

However, the basic configuration of the blast processing apparatus 1 is not limited to the circulation type configuration in which the abrasive is circulated in this way. For example, the blast processing apparatus 1 is a single-use disposable batch without reusing the used abrasive. In this case, the configuration provided for the wind separation of the dust such as cutting powder and the abrasive is omitted, and the abrasive after use in the processing chamber 21 by the dust collector 5 is omitted. Or dust may be removed and collected together.

In the illustrated example, the blasting apparatus is described as being configured as a suction type. For example, a direct pressure type blasting apparatus that introduces and injects both compressed gas and abrasive in a pressurized tank into a blast nozzle. On the other hand, the present invention can be applied, and various structures employed in known blasting apparatuses can be adopted as the basic configuration of the blasting apparatus.

In the blasting apparatus 1 of the present invention, liquid, in this embodiment, water is introduced into the blast nozzle 8 described above, and this water is collided with a compressed gas flow flowing in the blast nozzle 8 to have an average particle diameter of 1 mm. In the following, the atomized liquid is preferably atomized to 300 μm or less, more preferably 100 μm or less, and the atomized liquid is mixed into the compressed gas immediately before being injected to the workpiece W. On the other hand, the atomized liquid can be sprayed together with the abrasive.

As described above, the blasting apparatus 1 of the present invention supplies the liquid (water) to the blast nozzle 8 described above so that the atomized liquid can be mixed into the compressed gas injected toward the workpiece W. For this purpose, a liquid supply source (not shown) is provided, a liquid introduction path 88 for introducing water supplied from the liquid supply source into the blast nozzle 8 is provided in the blast nozzle 8, and the liquid supply source described above is further provided. A flow rate control means including a flow rate adjusting valve 7 and a pump is provided in a pipe line communicating between the liquid introduction path 88 of the blast nozzle 8.

(2) Blast Nozzle FIG. 2 shows a configuration example of the blast nozzle 8 provided in the blast processing apparatus 1 of the present invention.

The blast nozzle 8 shown in FIG. 2 has a basic structure provided in an existing suction type blast nozzle, and is constituted by a body 81 constituting a main body portion of the blast nozzle 8, a nozzle 82 attached to the body 81, and a jet 83. Has been.

The body 81 has a substantially cylindrical container shape formed in communication with the abrasive material introduction port 84 for introducing the abrasive material supplied from the abrasive material tank 3 which is a supply source of the abrasive material. The abrasive introduction chamber 85 is provided inside.

The nozzle 82 attached to the body 81 has a conical inner surface 82a constricted in a conical shape. By attaching the nozzle 82 to the front end side of the body 81, an abrasive formed in the body 81 is provided. The introduction chamber 85 and the flow path in the nozzle provided with the conical inner surface 82a are configured to communicate with each other.

A jet 83 is attached to the rear end side of the body 81 so that the tip is directed toward the center of the conical inner surface 82a of the nozzle 82. When a compressed gas is supplied from a compressed gas supply source (not shown), The abrasive material from the abrasive material tank 3 is sucked into the abrasive material introduction chamber 85 by the negative pressure generated by the jet gas compressed by the jet 83, and this abrasive material joins the compressed gas ejected from the jet 83. Thus, the point that it can be injected from the tip of the nozzle 82 has the same configuration as the known suction type blast nozzle 8.

In the blast nozzle 8 used in the blasting apparatus 1 of the present invention, the liquid from the liquid supply source (not shown) is supplied so that the liquid can be atomized and sprayed as described above. A liquid introduction path 88 for introduction into the blast nozzle 8 is provided, and a distal end 88a of the liquid introduction path 88 is provided with a compressed gas flow path provided in the blast nozzle 8, for example, a compressed gas provided in the jet 83. The high-speed compressed gas flow that flows through the blast nozzle 8 or the high-speed compressed gas that is jetted from the blast nozzle 8 is opened in front of the discharge port of the jet 83 or in front of the discharge port of the jet 83 and further at the injection port of the blast nozzle. By making the liquid collide with the flow, the liquid can be atomized and sprayed.

In the present invention, the liquid ejected from the tip 88a of the liquid introduction path 88 is made to collide with the high-speed compressed gas flow and atomize, so that the liquid can be atomized more suitably. You may install a mesh material in opening of the front-end | tip 88a of the introduction path 88. FIG. Thereby, after the liquid supplied from the liquid introduction path 88 passes through the mesh material and is once atomized, the liquid is further atomized by colliding with the high-speed compressed gas flow.

The mesh material used in the present invention is not particularly limited. For example, the mesh material is formed as a whole by knitting a wire made of metal or resin into a mesh shape, or by forming fine holes in a plate. Various things can be used.

In the embodiment shown in FIG. 2, the conduit that becomes the liquid introduction channel 88 is concentrically disposed in the compressed gas channel 86 formed in the jet 83, and the inner wall of the compressed gas channel 86 and the liquid The compressed gas is allowed to flow between the outer walls of the introduction path 88, the tip 88 a of the liquid introduction path 88 is opened at the same position as the opening of the jet 83, and the liquid discharged from the tip 88 a of the liquid introduction path 88 is removed. , It is atomized by colliding with a high-speed, high-pressure compressed gas flow that flows on the outer periphery.

With this configuration, in the blast processing apparatus 1 of this embodiment, the liquid is sucked from the tip 88a of the liquid introduction path 88 due to the negative pressure generated in the abrasive introduction chamber 85, and merges with the compressed gas flow. Therefore, the liquid is supplied in the blast nozzle 8 without providing a liquid fixed quantity supply device such as a pump for supplying the liquid from a liquid supply source (not shown) such as a liquid tank into the blast nozzle 8. In addition to being able to atomize, the introduction of liquid from the liquid supply source automatically starts and stops in conjunction with the start and stop of the introduction of compressed gas to the blast nozzle 8. No dripping or the like due to forgetting to stop.

The configuration in which the liquid collides with the compressed gas flow is not limited to the configuration shown in FIG. 2, and various known gas blast type two-fluid nozzle (atomizer) configurations are applied to the jet 83 configuration. In addition, the liquid introduction into the blast nozzle may be performed by using a liquid metering means such as a pump instead of the configuration using the negative pressure in the abrasive introduction chamber as described above. It is good also as what is performed by providing in the inside of the tank which is or in piping between a liquid supply source and a blast nozzle.

The liquid supply position for the blast nozzle 8 may be different from the position shown in FIG. 2, and as an example of the liquid introduction position for the suction type blast nozzle, as shown in FIG. 8 is formed in the outer periphery of the front end of the jet 83, and the liquid introduction path 88 is formed. The space is opened in the forward direction of the jet 83, and the liquid is introduced into the liquid introduction path 88. The liquid thus injected may be sprayed so as to wrap around the outer periphery of the compressed gas injected from the jet 83 so that the liquid collides with a high-speed, high-pressure compressed gas flow to be refined.

Furthermore, as shown in FIG. 3, the tip 88a of the liquid introduction path 88 is opened at the position where the abrasive introduction chamber 85 and the blast nozzle 8 are formed, and the liquid introduction path 88 is generated by the negative pressure generated by the compressed gas flow. It may be configured to cause the liquid in the cylinder to be sucked and collide with the compressed gas flow flowing in the blast nozzle 8 or the compressed gas flow injected from the blast nozzle 8, or the compressed gas formed in the jet 83 The liquid of the liquid supply source may be quantitatively supplied by a pump into the compressed gas flow path formed in the flow path or the nozzle 82, and the liquid introduction described with reference to FIGS. Instead of the position, or together with the liquid introduction position described with reference to FIGS. 2 and 5, the liquid may be introduced from any one or a plurality of positions of the liquid introduction position shown in FIG.

Further, as shown in FIG. 4, the liquid introduction position for the direct pressure type blast nozzle is generated when the tip 88a of the liquid introduction path 88 is opened at the position where the injection port of the blast nozzle 8 is formed and the compressed gas is injected. The liquid in the liquid introduction path 88 may be sucked by a negative pressure to collide with the compressed gas ejected from the blast nozzle 8, or a jet 83 ′ provided in the blast nozzle body 81 ′. The leading end 88a of the liquid introduction path 88 is opened in a compressed gas passage formed in the nozzle 82 ′ attached to the tip of the blast nozzle 8 or the inside of the blast nozzle 8 to pump the liquid from the liquid supply source. May be introduced into the blast nozzle 88, and the liquid can be introduced through any one of these or a plurality of locations.

Note that a flow rate control means for controlling the flow rate of the liquid introduced into the liquid introduction pipe 88 is provided in the pipe line extending from the liquid supply source to the liquid introduction path 88, and the amount of liquid introduced into the blast nozzle 8. Can be adjusted.

In the present embodiment, the flow rate adjusting valve 7 is provided as a flow rate control means in the pipe between the liquid introduction path 88 having the tip 88a opened at the position where the negative pressure is generated and the liquid supply source. In the present embodiment, the flow rate adjusting valve 7 has an opening that can be adjusted in eight steps. However, a valve that can adjust the opening steplessly may be used to adjust the flow rate of the liquid. Various valves can be used if possible.

Also, a pump is provided as the above-described flow rate control means between the liquid introduction path 88 having the tip 88a opened at a position other than the position where the negative pressure is generated and the liquid supply source. The amount of liquid supplied to the blast nozzle 8 can be controlled by controlling the rotation speed.

Even when the leading end 88a of the liquid introduction path 88 is opened at the position where the negative pressure is generated, a configuration in which a pump is provided between the liquid introduction path 88 and the liquid supply source may be employed. In this configuration, a flow rate adjusting valve may be provided on the secondary side of the pump so that the flow rate of the liquid introduced into the blast nozzle 8 is adjusted.

Furthermore, without providing a container such as a liquid tank as a liquid supply source, the liquid introduction path 88 can be communicated with a water supply intake (faucet) so that the water supply can be used as a liquid supply source. By introducing the liquid into the liquid introduction path 88 using the feed water pressure, the above-described installation of the pump can be omitted.

2. The operation of the blast processing apparatus 1 shown in FIG. 1 configured as described above is provided with the blast nozzle 8 shown in FIG. 2 as an example.

The abrasive is supplied into the abrasive tank 3 as an abrasive supply source, and a liquid tank (not shown) as a liquid supply source is filled with a liquid such as water. In this state, the abrasive tank 3 is illustrated with respect to the blast nozzle 8. The introduction of compressed gas from the compressed gas supply source is started.

In this way, when the introduction of the compressed gas is started, a high-speed compressed gas is ejected from the tip of the jet 83 of the blast nozzle 8 to generate a high-speed air flow in the nozzle 82 in the direction of the ejection port.

Therefore, the gas in the abrasive material introduction chamber 85 is sucked into the nozzle 82 by such a compressed gas flow, and as a result, the pressure in the abrasive material introduction chamber 85 becomes negative and the abrasive material introduction port 84 is opened. Then, the abrasive from the abrasive tank 3 is introduced into the abrasive introduction chamber 85, and this negative pressure sucks out the liquid in the liquid introduction path 88 from the tip 88a of the liquid introduction path 88, and the sucked liquid. Are atomized by the high-speed compressed gas blown out from the jet 83 and mixed into the compressed gas, mixed with the abrasive material in the compressed gas, and sprayed from the blast nozzle 8.

In the blasting method of the present invention, a suitable abrasive injection amount is 2 g / min to 20 kg / min. On the other hand, the amount of liquid introduced into the blast nozzle 8 is relatively 0.06 cc to 150 cc / min. Since the amount of the liquid is small and the liquid sprayed together with the abrasive is atomized by the collision with the high-speed compressed gas flowing in the blast nozzle 8 and sprayed from the blast nozzle 8, the liquid is sprayed from the blast nozzle 8. The sprayed liquid is combined with the blast nozzle 8 and the workpiece W in combination with a sudden drop in the pressure of the compressed gas and the surface of the workpiece being heated due to the collision with the abrasive. The space evaporates in the space or the surface of the workpiece W, and a large amount of heat of vaporization is taken from the space and the surface of the workpiece W.

As a result, when performing blasting by the method of the present invention, not only can the generation of static electricity be prevented due to the increase in humidity accompanying the evaporation of the liquid, but also compared with general blasting that does not involve liquid spraying. , It is considered that effects such as improvement of cutting speed, removal efficiency of coating film and burrs, prevention of abrasive sticking to the surface of the workpiece W, prevention of warpage and elongation of the workpiece, etc. .

That is, in the method of the present invention, water is jetted, but the jetted water evaporates quickly as described above. Therefore, even if the surface of the workpiece is not wetted, the degree is known. The amount of water film that absorbs the collision energy of the abrasive is suppressed from being formed on the surface of the workpiece.

On the other hand, although the formation of the water film described above is suppressed, since the sprayed water loses a large amount of heat of vaporization when it evaporates, the increase in the surface temperature of the work piece is suppressed. Compared to dry blasting, which can cause such softening as a result of suppressing the absorption of collision energy of abrasives due to softening of the surface of the workpiece, the coating film formed on the surface of the workpiece to be removed, burrs, etc. Even in this case, it is considered that the processing amount can be improved and the removal efficiency of the coating film and burrs can be improved.

Further, it is also considered that the above-described piercing of the abrasive is caused because the surface of the workpiece is softened with the temperature rise, so that the injected abrasive is likely to pierce the surface of the workpiece.

Furthermore, the elongation and warpage that reduce the dimensional stability of the product are also considered to be caused by the difference in elongation due to the temperature rise of the work piece and the front and back surfaces.

Therefore, it is considered that the above effect was obtained by performing blasting by the method of the present invention and suppressing the wetting of the workpiece and the temperature rise.

In the blasting method of the present invention, the principle is unknown, but the recovered abrasive is less cracked or chipped than the conventional blasting performed without spraying the liquid, and the wear rate of the abrasive is reduced. It has been confirmed that it can also be reduced.

As described above, the blasting method of the present invention can effectively prevent the occurrence of sparks caused by static electricity during processing, and can eliminate the damage and loss of products such as products, especially electronic parts. It was also possible to eliminate the damage to the electrodes provided in the product.

In addition to preventing the product from being charged, it is also possible to prevent static electricity from being charged in the circulating system of abrasives, the inner wall of the cabinet, the inner wall of the duct, and the like. Abrasion material is prevented from adhering to the inside of the tank 3, and the abrasive material adhering to the cyclone type abrasive tank 3 collides with the abrasive material in the swirling flow, thereby reducing the amount of abrasive material flowing into the dust collector without being recovered. Effects such as improvement in recovery efficiency could also be obtained.

In addition, the blasting method of the present invention not only has the effect of preventing the generation of static electricity, but also improves the processing amount, improves the removal efficiency of the coating film and burrs, and improves the surface roughness in comparison with general dry blasting. Effects such as prevention of discoloration due to deterioration and scoring, prevention of sticking of abrasives that become contaminants during coating and plating after blasting, prevention of warpage and elongation of workpieces that reduce dimensional stability of the product, etc. It was possible to obtain an excellent effect that cannot be predicted from the prior art.

The results of the confirmation test that the above-described effects can be obtained for the blasting method of the present invention are shown below.

As a blasting apparatus, both dry blasting (comparative example) and blasting of the present invention (example) are performed using a suction type blasting apparatus (see FIG. 1 for an outline of the structure) and liquid ( In the blasting process (example) of the present application in which blasting is performed while supplying water), the blast nozzle is provided with the liquid introduction path 88 in the compressed gas flow path 86 of the jet 83 as described with reference to FIG. Or, as described with reference to FIG. 5, either one having a chamber that becomes a liquid introduction path 88 on the outer periphery of the tip of the jet 83 is used, while dry blasting (comparative example) 2 and FIG. 5 are measured by spraying an abrasive without supplying water, or a blast nozzle having a general jet (the structural blast shown in FIG. 2). Was measured it performs blasting using something from nozzle jet 83 of the removed structure of the liquid introducing path 88).

(1) Confirmation of antistatic effect The amount of charge when an acrylic plate (100 × 100 × 5 mm) was blasted was measured.

Nylon beads (NB) # 0303 (average particle size 300 μm) manufactured by Fuji Seisakusho were used as the abrasive, and the abrasive was sprayed at a nozzle distance of 160 mm, an injection pressure of 0.3 MPa, and an injection time of 40 minutes. .

The processing is performed by attaching the blast nozzle described with reference to FIG. 2 to the circulation type blast processing apparatus having the structure shown in FIG. 1 and installing the flow rate adjusting valve 7 for adjusting the amount of water introduced into the blast nozzle 8. It gradually opens from the closed state to increase the amount of water supply, changes in the charge amount of the acrylic plate (measuring instrument: using 3M 709STATICORSENSOR), changes in temperature and humidity in the processing chamber, and The state was observed. The measurement results are shown in Table 1.

From the above results, the amount of charge can be reduced by 40% or more just by supplying a small amount of water of 0.06 cc / min with respect to the amount of charge in dry blasting performed with no water supply with the flow control valve 7 fully closed. It has been confirmed that high static electricity prevention effects can be obtained even by spraying a relatively small amount of water.

After that, the charge amount further decreased as the water supply amount was increased, and at 15.0 cc / min, a decrease of 90% or more was observed with respect to the charge amount when no water supply was made.

Also, in blasting with no flow of water with the flow control valve 7 fully closed, the blasted cabinet has an abrasive material all over the surface of the workpiece, the inner wall of the cabinet, the surface of the rubber hose and blast nozzle, etc. In the cabinet after blasting by the method of the present invention, although the accumulation of the abrasive on the stepped part of the wall surface was confirmed, the abrasive was adhered due to static electricity. Could not be confirmed.

(2) Confirmation of increase in machining volume (cutting speed)
(2-1) Measurement of change in machining amount with respect to change in water supply amount Using the blast nozzle shown in Fig. 2 and adjusting the opening of the flow control valve, the water supply amount to the blast nozzle is changed and the workpiece machining amount is also changed. Changes in (cutting amount) were measured.

The measurement was performed on a test piece made of the material shown in Table 2 below, using an injection distance of 120 mm, an abrasive material of alumina abrasive (“Fuji Random A # 60” manufactured by Fuji Seisakusho, and an injection pressure of 0.4 MPa). Then, machining was performed under the conditions shown in Table 2, and the weight of the test piece before and after machining was measured, and the weight loss was determined as the cutting amount.

Measured results for each test piece are shown in Tables 3 to 11 and FIGS. In Tables 3 to 11, the weight loss ratio indicates the ratio to the weight loss during processing with no water supply.

As a result of the above, even when the test piece of any material is processed, the amount of cutting can be increased compared to the case where the blasting process is performed without supplying water (comparative example). I was able to confirm.

The increase in the amount of cutting increases as the amount of water supplied increases, but when the amount of cutting increases to some extent, the increase in water supply leveled off without further increase.

For this reason, as in the blasting method of the present invention, by ejecting a relatively small amount of liquid together with the abrasive, not only the antistatic effect described above, but also the unexpected effect of increasing the processing amount can be obtained. Was confirmed.

Moreover, it was confirmed that such an effect was obtained regardless of the material of the workpiece.

(2-2) Confirmation of processing volume increase effect due to change of abrasive material Zircon grid ("FZG 60" manufactured by Fuji Seisakusho (particle size 0.125 to 0.250mm)) using the blast nozzle shown in Fig. 5 The result of processing a test piece made of stainless steel by spraying and the result of processing a test piece by spraying an abrasive material made of alumina (“Fuji Random A # 60” (average particle size 230 μm) manufactured by Fuji Seisakusho Are shown in Tables 12 and 13, respectively.

From the above results, when zircon grid (FZG-60) is used as an abrasive, an alumina abrasive (“Fuji Random A # 60” (particle size 250 to 212 μm) manufactured by Fuji Seisakusho) is used. In any case, an increase in the processing amount has been confirmed, and the effect of increasing the processing amount obtained in the present application is an effect that can be obtained without change even when the type of abrasive used is changed. confirmed.

The increase in the processing amount is 1.5 times or more when using zircon grid (FZG-60), and 1.3 to 1.4 times when using alumina abrasive (“Fuji Random A # 60” manufactured by Fuji Seisakusho). It was confirmed that a significant increase in the processing amount was obtained.

(3) Confirmation of the state of abrasive piercing Among the test pieces processed in “(2)” and “(2-1) Measurement of changes in processing amount with respect to changes in water supply” above, urethane rubber plates, stainless steel plates, iron plates, The component at the center of the processed part of the acrylic plate and epoxy glass plate was measured using an EDX (energy dispersive X-ray analysis) apparatus (INC Energy manufactured by Oxford) and the alumina abrasive used (Fuji Manufacturing “Fuji” The mass concentration of aluminum, which is a main component of random A # 60 "), was evaluated as the amount of abrasive piercing the test piece.

The measurement results are shown in Tables 14 to 18 and FIGS. In Tables 14 to 18, the Al mass concentration ratio indicates the ratio to the Al mass concentration with no water supply.

From the above results, it was confirmed that by supplying the liquid, the piercing of the abrasive was reduced as compared with the case of blasting without water supply.

In addition, even when processing by the known wet blast method, it is possible to reduce the amount of abrasive stab, but as described above, the known wet blasting method requires less cutting than dry blasting. However, it was not possible to achieve both workability and workability.

In contrast, in the method of the present application, as described above, not only in comparison with conventional wet blasting, but also in comparison with blasting without water supply, an improvement in cutting amount can be obtained simultaneously. An unpredictable effect of preventing the abrasive material from being stuck can be obtained.

(4) Abrasive consumption and particle size measurement results The blasting method of the present invention (Example) using the blast nozzle shown in FIG. 2 and a known blast nozzle (from the blast nozzle of FIG. 2 to the liquid introduction path) Tests made of SUS304 using zircon beads (FZB-60 manufactured by Fuji Seisakusho (average particle size 200 μm) as an abrasive by dry blasting method (comparative example) using a structure with 88 omitted) The piece was blasted at an injection pressure of 0.5 MPa, the consumption of the abrasive after blasting was measured, and the state of the abrasive particles was observed.

The injection is performed by a continuous injection method (abrasive circulating type blasting apparatus shown in FIG. 1), and the weight of the abrasive put into the abrasive tank of the blasting apparatus at the beginning of measurement and the recovered abrasive The weight of each was measured, and the weight of the decrease was evaluated as the consumption.

The blasting time is 45 minutes, and the amount of water introduced in the blasting method of the present invention is 6 cc / min.

Table 19 shows the measurement results of the abrasive consumption, and FIG. 20 shows the state of the abrasive particles after use.

From the above results, it was confirmed that in the blasting method of the present invention, the consumption amount of the abrasive was reduced as compared with the known dry blasting method.

Further, from the observation result of the particle size (see FIG. 20) of the recovered abrasive, the abrasive after use in the dry blasting method is compared with the abrasive after performing the blasting method of the present invention. However, it was confirmed that the crushing progressed faster and the particle size was smaller.

(5) Measurement of surface temperature of workpiece
(5-1) Temperature measurement with thermocouple Spray distance is 100mm, spray pressure is 0.3MPa and 0.5MPa, and Zirco beads (FZB-400 made by Fuji Seisakusho: particle size <0.05mm) are used as abrasives. Then, the abrasive was sprayed onto a 15 mm × 15 mm × 0.5 mm copper plate, and the temperature change of the copper plate was measured.

The temperature is measured by attaching a thermocouple thermometer to the back of the copper plate and making the temperature change readable. Using the blast nozzle shown in FIG. The highest temperature displayed during the injection of the abrasive was used as the measured value. Table 20 shows the measurement results.

From the above results, it was confirmed that according to the blasting method of the present invention, the temperature rise of the workpiece can be greatly reduced as compared with the case of processing by the dry blasting method.

(5-2) Confirmation of heat generation The temperature measured in the above test is a very short time of spraying for a few seconds, and the temperature at the back of the copper plate to be treated is measured. It is expected that the temperature rise on the surface side where the collision occurs is so high that the surface of the workpiece is softened instantaneously.

Therefore, in order to grasp the difference in the surface temperature of the workpiece between the blasting method of the present invention and the dry blasting method in an easy-to-understand manner, the coating film peeling of the resin product made of PC (polycarbonate) and the PPS (polyphenylene) The processing state was compared by applying the blasting treatment of the present invention and the known dry blasting treatment to the deburring treatment of the resin product made of (Sanphide).

In addition, the coating film peeling of the resin product made from PC uses a blast nozzle as shown in FIG. 2 to apply a high-purity alumina abrasive (“Fuji Random WA WA # 600” manufactured by Fuji Seisakusho) to a processing pressure of 0.4 MPa and a nozzle distance. Injecting at 70 mm, processing was performed with a water supply amount of 5 cc / min in the method (Example) of the present invention, and with no water supply in the comparative example.

In addition, PPS (polyphenylene sunfide) resin products are deburred using the blast nozzle shown in Fig. 2, using nylon beads ("FNB -0303" manufactured by Fuji Seisakusho) with a working pressure of 0.4 MPa and a nozzle distance. Injection was performed at 20 to 30 mm, and processing was performed with a water supply amount of 3 cc / min in the method of the present invention (Example), and with no water supply in the comparative example.

The result of measuring the surface roughness of the PC product after peeling the coating film is shown in FIG. 21, and the result of measuring the surface roughness of the PPS product after deburring is shown in FIG.

In any of the treatment results, the resin product treated by the method of the present invention [see FIGS. 21A and 22A] is a resin product of a comparative example performed in a dry process [FIG. 21B and FIG. It can be seen that the surface roughness is less than that of (B)], and it is considered from this result that the dry blasting process was greatly deformed by softening due to heat generation.

In addition, the surface of the resin product treated by dry blasting turned dark due to scorching, whereas the resin product processed by the method of the present invention confirmed the occurrence of such scoring. In view of this, it was confirmed that the method of the present invention suitably prevented heat generation of the workpiece.

In addition, the occurrence of such a burn occurred not only when processing a resin product, but also when processing a metal product such as aluminum, but in the method of the present invention, Even in the treatment of such metal products, the occurrence of scorching could be prevented.

Further, in the dry blasting process, the peeling of the coating film which took 11 to 12 seconds is shortened to 6 to 7 seconds in the method of the present invention. When the blasting process of the present invention is performed, the removal efficiency of the coating film is reduced. It was confirmed that improvement of

It should be noted that this effect was confirmed not only for the resin as the base material but also for the paint stripping of metal surfaces such as aluminum alloy, magnesium alloy, zinc alloy, brass alloy, and iron.

In the deburring process, even burrs that could not be removed by dry blasting can be removed by the blasting process of the present invention, and the blasting process of the present invention is also effective when used for the deburring process. It was confirmed that.

The difference is that in dry blasting, the surface temperature of the workpiece rises, and the coating film and burrs soften to absorb the impact when the abrasive material collides, making peeling and removal difficult. On the other hand, in the method of the present invention, the surface of the workpiece is cooled, so that the softening of the coating film and burrs is suppressed, and the coating film and burrs are kept hard (and therefore brittle). It is thought that this is because peeling and removal are easily performed due to the collision.

(6) Checking the state of warpage Using the blast nozzle shown in Fig. 2 and using a zircon shot (FZB-425, manufactured by Fuji Seisakusho (0.425 to 0.60 mm average particle size 513 μm)) as an abrasive. Processing on an almen strip (A strip) was performed.

The processing pressure is 0.3MPa and 0.5MPa, the processing time is 20 seconds, the water supply amount is changed, and the arc height value (curved height of the test piece) is measured. evaluated. Table 21 shows the measurement results.

From the above results, it was confirmed that when the blasting is performed by the method of the present invention, the warpage generated on the workpiece can be slightly reduced.

1 Blasting device 2 Cabinet 21 Processing room 3 Abrasive material tank (cyclone)
DESCRIPTION OF SYMBOLS 5 Dust collector 6 Blower 7 Flow control valve 8 Blast nozzle 81 Body 82 Nozzle 82a Cone inner surface 83 Jet 84 Abrasive introduction port 85 Abrasive introduction chamber 86 Compressed gas flow path 88 Liquid introduction path 88a Tip (of liquid introduction path)
91 Abrasive recovery pipe

Claims

In a blasting method of injecting an abrasive with a compressed gas through a blast nozzle to a workpiece,
Liquid is introduced into the blast nozzle, and the liquid collides with the compressed gas flowing through the blast nozzle or the compressed gas ejected from the blast nozzle to atomize, and the atomized liquid is mixed with the compressed gas and the polishing. While jetting with the material,
A blasting method, wherein an introduction amount of the liquid to the blast nozzle is 0.06 cc / min to 150 cc / min.
In a blasting apparatus for injecting a compressed gas flow supplied from a compressed gas supply source from a blast nozzle as a mixed fluid with an abrasive,
One end of the blast nozzle can communicate with a liquid supply source, and the other end is opened in a flow path of a compressed gas in the blast nozzle or an injection port of the blast nozzle, and is introduced from the liquid supply source. A liquid introduction path for causing the liquid to collide with a compressed gas flow flowing in the blast nozzle or a compressed gas flow injected from the blast nozzle to atomize the liquid,
A blasting apparatus comprising flow control means between the liquid introduction path and the liquid supply source.
The blast nozzle includes a nozzle in a jet direction of a jet communicating with a compressed gas supply source, and includes an abrasive introduction chamber communicating between the jet and the nozzle and an abrasive supply source, and jets of a compressed gas flow from the jet A suction-type blast nozzle that generates a negative pressure in the abrasive introduction chamber and sucks the abrasive from the abrasive supply source and jets it as a mixed fluid;
The blasting apparatus according to claim 2, wherein the other end of the liquid introduction path is opened in a compressed gas flow path provided in the jet or at a position in front of the jet outlet of the jet.
The liquid introduction path is formed by a pipe line concentrically inserted into the compressed gas flow path provided in the jet, and the other end of the liquid introduction path is opened at the jet outlet of the jet. 4. A blasting apparatus according to claim 3, wherein
The blasting apparatus according to any one of claims 2 to 4, further comprising a liquid fixed amount supply means for supplying a fixed amount of liquid from the liquid supply source to the liquid introduction path.