JP7083213B2 - Abrasive mixed liquid polishing device, polishing method using it, and laminated wire mesh filter for abrasive grain separation of abrasive mixed liquid polishing device - Google Patents

Description

The present invention is an abrasive material mixing liquid polishing apparatus suitable for polishing the inside of a metal, for example, the inside of a flow path formed for the purpose of cooling or temperature control of a mold or the like, a polishing method using the liquid polishing apparatus, and an abrasive material mixing device. The present invention relates to a laminated wire mesh filter for separating abrasive grains in a liquid polishing device.

In recent years, as shown in Patent Document 1 and Non-Patent Document 1, the use of metal stereolithography for forming a three-dimensional shape has been promoted by laminating a sintered layer obtained by irradiating a metal powder material with a light beam. Has been done.
In the mold obtained by this metal stereolithography, there is a problem that the inner surface of the obtained inner water pipe is rough due to the molding method of laminating the sintered layers, and there is a concern that the flow rate is insufficient or clogged due to red rust or scale deposition. rice field.

For the purpose of solving this problem, Patent Document 2 describes an inner surface polishing device for a hollow portion formed in communication with the inside of a metal member, and is connected to one opening and the other opening of the communicated hollow portion, respectively. It has a pair of storage tanks for the abrasive mixed liquid and a pressure increasing means for alternately increasing the internal pressure of the pair of storage tanks, and the abrasive mixed liquid reciprocates in and out of the hollow portion to be hollow. Abrasive mixed liquid polishing device that polishes the inner surface of the part is used to mix the abrasive in the hollow part of the three-dimensional shape formed by communicating with the inside of the sintered optical molding mold manufactured by laser optical molding. The liquid is forcibly flowed in to polish the inner surface of the hollow portion. The abrasive grains mixed in the abrasive mixed liquid are alumina, the average particle size is 90 to 350 μm, and the abrasive grain concentration is 2 to 16 vol%. Disclosed is a method of polishing with an abrasive mixed liquid of an optical molding mold, which is characterized by the above range.

JP 2014-31018 Japanese Patent No. 5477739

Panasonic Technical Journal Vol.62 No.2 Nov.2016

In the polishing method disclosed in Patent Document 2, during the fluid polishing process, the abrasive grains and the liquid are mixed in the storage tank to form an abrasive mixed liquid, and as a result, the abrasive mixed liquid is also supplied to the pressure boosting portion. There was a problem that the inner surface of the cylinder of the booster and the piston seal were worn and the booster cylinder failed.
There is also a problem that the processed metal powder generated during polishing also damages the inner surface of the cylinder and the piston seal.
In view of the problems of the prior art, the present invention has a highly durable and industrially practical abrasive material mixed liquid polishing apparatus, a polishing method using the same, and a laminated wire net for abrasive grain separation of the abrasive material mixed liquid polishing apparatus. The purpose is to provide a filter.

The abrasive mixed liquid polishing apparatus of the present invention includes a pair of abrasive mixed liquid storage tanks connected to one opening and the other opening of the hollow portion of the mold formed in communication with the inside of the mold. It has a hydraulic pressure generating means that alternately increases the internal pressure of the pair of storage tanks, and the abrasive mixed liquid reciprocates in and out of the inner surface of the hollow portion of the mold so that the inner surface of the hollow portion of the mold is formed. In the abrasive mixed liquid polishing apparatus to be polished, an abrasive grain separating means for separating abrasive grains from the abrasive mixed liquid is arranged in the abrasive mixed liquid flow path between the hydraulic pressure generating means and the mold. It is characterized by that.

In the polishing method using the polishing material mixed liquid of the present invention, the polishing material mixed liquid is forcibly flowed into the hollow portion formed in communication with the inside of the mold by using the polishing material mixed liquid polishing apparatus of the present invention, and the inner surface of the hollow portion is formed. A step of polishing, a step of separating abrasive grains in the polishing material mixed liquid flow path between the hydraulic pressure generating means and the mold, and a step of adsorbing metal debris in the pair of storage tanks. It is characterized by having.

The laminated wire mesh filter for abrasive grain separation of the abrasive mixed liquid polishing apparatus of the present invention is formed by laminating a relatively dense wire mesh filter and a relatively coarse wire mesh filter, with the dense wire mesh filter as the outside. It is characterized in that it has a tubular shape with the coarse metal filter inside, one end having an opening, and the other end having a closing portion.

The polishing material mixed liquid polishing apparatus of the present invention has high durability, and a polishing method using the polishing material can be industrially put into practical use. Further, the laminated wire mesh filter for separating abrasive grains of the abrasive material mixed liquid polishing apparatus of the present invention can be industrially put into practical use in the abrasive material mixed liquid polishing apparatus of the present invention and the polishing method using the same.

The schematic diagram of the abrasive material mixed liquid polishing apparatus of embodiment of this invention. A partially enlarged view of the abrasive material mixed liquid polishing apparatus shown in FIG. 1. A perspective photograph of a component of an abrasive mixed liquid polishing apparatus according to an embodiment of the present invention. The side view photograph of the part of the abrasive material mixed liquid polishing apparatus of embodiment of this invention. A photograph of another side view of a component of the abrasive mixed liquid polishing apparatus according to the embodiment of the present invention. Another side photograph of the component of the abrasive mixed liquid polishing apparatus of embodiment of this invention. Photograph of a side view of a member used for a component of an abrasive mixed liquid polishing apparatus according to an embodiment of the present invention. A photograph of the other side of the member shown in FIG. 7. The schematic diagram of the abrasive material mixed liquid polishing apparatus of another embodiment of this invention. FIG. 3 is a partial schematic diagram of an abrasive mixed liquid polishing apparatus according to still another embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described.
As shown in FIGS. 1 and 2, in the abrasive material mixed liquid polishing apparatus 1 of the present embodiment, one opening 2a and the other opening 2b of the hollow portion 2 of the mold are formed so as to communicate with each other inside the mold. It has a pair of storage tanks 3 for mixed liquids of abrasives, and a hydraulic pressure generating means 4 for alternately increasing the internal pressure of the pair of storage tanks 3. In the present embodiment, the hydraulic pressure generating means 4 is composed of both rod hydraulic cylinders 4a, a piston 4b driven by both rod hydraulic cylinders 4a, and a hydraulic pressure generating cylinder 4c provided with packing 4b-1. It is not limited to this as long as it can generate hydraulic pressure such as air pressure and electric power.

The base (not shown) of the pair of stainless steel storage tanks 3 is an iron frame, and the storage tank 3 is placed on the iron frame. Further, each of the pair of storage tanks 3 is provided with an abrasive mixed liquid flow pipe 5 inside the storage tank 3 so as to extend the tip to the vicinity of the bottom 3a of each of the storage tanks 3, and each tip 5a is cut diagonally. ..
As shown in FIG. 2, the bottom portion 3a of each of the storage tanks 3 is formed into an inverted trapezoidal shape by the tapered portion 3b.

Abrasive grains 6 which are alumina are stored in each of the pair of storage tanks 3, and the abrasive grains 6 are stored in the vicinity of the bottom portion 3a formed in an inverted trapezoidal shape of the storage tank 3. The material of the abrasive grains 6 is not particularly limited, and is appropriately selected from the viewpoint of cost, properties, and the like.
However, it is the efficiency of polishing that the average particle size of the abrasive grains 6 is 1/8 to 1/12 of the hole diameter of the hollow mold portion 2 to be polished, and the inner side surface 2c of the hollow mold portion 2 obtained. It is desirable from the viewpoint of surface smoothness. If it exceeds 1/8, the abrasive grains 6 in the hollow portion 2 of the mold are likely to be clogged, while if it is less than 1/12, the polishing efficiency is lowered.

In the abrasive mixed liquid polishing apparatus 1 of the present embodiment, the abrasive grain separating means for separating the abrasive grains from the abrasive mixed liquid in the abrasive mixed liquid flow path 7 between the hydraulic pressure generating means 4 and the mold hollow portion 2. 8 is arranged.
The abrasive grain separating means 8 can be a laminated wire mesh filter housed in the storage tank 3, and the laminated wire mesh filter is attached to the opening 7a in the storage tank 3 of the liquid flow path 7 from the hydraulic pressure generating means 4. Will be done.
This laminated wire mesh filter can be, for example, a 5-layer laminated wire mesh filter, and the opening diameter of the outermost wire mesh filter is about 40 μm. Further, the inner wire mesh filter laminated on the outermost wire mesh filter has a coarser mesh and a larger opening diameter. In the present embodiment, three layers of a wire mesh filter having a coarser mesh size and a larger opening diameter than the outermost wire mesh filter are laminated inside the outermost wire mesh filter, and further inside the wire mesh filter having a coarser mesh size and an opening diameter. Large wire mesh filters are laminated to form a 5-layer laminated wire mesh filter as a whole. Such a laminated wire mesh filter is clogged in the process of separating abrasive grains which are abrasives. However, the clogging can be cleared by ultrasonic cleaning, and it can be regenerated. Depending on the embodiment, wire mesh filters having a large opening diameter may be gradually laminated inward.

On the other hand, when a porous filter is used without using a laminated wire mesh filter, for example, clogging occurs in the process of abrasive grain separation, and the clogging cannot be cleared by ultrasonic cleaning, so that the porous filter is disposable. It is necessary to make it a cause of high cost.
Further, the laminated wire mesh filter of the present embodiment obtained as described above has a withstand voltage of 5 Mpa, and is superior in withstand voltage to a porous filter having a withstand voltage of about 1 Mpa, which is necessary for a polishing method using an abrasive mixed liquid. It is possible to secure the flow pressure of the mixed liquid of the abrasive material, and it is possible to polish the inner side surface 2c of the mold hollow portion 2 having various diameters.
The number of laminated wire mesh filters is not limited to the five-layer wire mesh filter of the present embodiment, and can be appropriately determined experimentally according to the required flow pressure of the abrasive mixed liquid and the like.

3 and 4 are external photographs of the five-layer wire mesh filter used in the abrasive mixed liquid polishing apparatus 1 of the present embodiment, and are shown in the opening at one end shown in the external photograph of FIG. 5 and the external photograph of FIG. It is formed in a cylindrical shape having a closing portion at the other end shown.
As shown in FIG. 7, the five-layer wire mesh filter has three layers of a wire mesh filter having a coarser mesh than the outermost wire mesh filter and a larger opening diameter inside the outermost wire mesh filter, and further inside the wire mesh filter. A wire mesh filter having a coarse mesh and a large opening diameter is laminated to form a five-layer laminated wire mesh filter as a whole, and the wire mesh filter having the largest opening diameter shown in FIG. 8 is wound in a cylindrical shape so as to be on the inner surface.

Further, in the abrasive material mixed liquid polishing apparatus 1 of the present embodiment, the metal scrap adsorption means 9 is arranged in the pair of storage tanks 3 as shown in FIGS. 1 and 2. The metal debris 10 inevitably generated by polishing the inner side surface 2c of the mold hollow portion 2 by the metal debris adsorbing means 9 is adsorbed.
As the metal scrap adsorption means 9, for example, a strong permanent magnet can be used, and a commercially available neodymium-iron-boron permanent magnet whose surface is corrosion-proof by plating may be used. As shown in FIG. 2A, the abrasive grains 6 are housed in the bottom 3a of the storage tank 3, and the metal scrap adsorption means 9 is placed on the abrasive grains 6.

At that time, when a commercially available neodymium-iron-boron permanent magnet (magnetic flux density 0.2 tesla) having a low and flat cylindrical shape whose surface is corroded by plating is used as the metal scrap adsorption means 9. As shown in FIG. 2B, the base (not shown) of the storage tank 3 is an iron frame even if the outer peripheral side having a cylindrical curved shape is placed as a grounding portion, and the iron frame and the metal are used. The installation state is maintained in such a manner that the bottom 3a of the storage tank 3 is sandwiched by the dust suction means 9 by a strong magnetic force. When the metal debris adsorbing means 9 is installed in this way, the amount of abrasive grains 6 covering the curved outer peripheral side of the metal debris adsorbing means 9 is small, and the mixed liquid flow pipe of the abrasive grains 6 is used in the polishing process. The inflow to 5 is not hindered.

On the other hand, when the cylindrical flat side is installed as the ground contact portion as shown in FIG. 2 (c), the amount of abrasive grains 6 covering the metal scrap adsorbing means 9 becomes large and is adsorbed by the metal debris adsorbing means 9. It has been phenomenologically confirmed that the interaction with the metal scrap 10 works and the inflow of the abrasive grains 6 into the mixed liquid flow pipe 5 is hindered.

As shown in FIGS. 2 (d) and 2 (e), 10 permanent magnets having a magnetic flux density of 0.2 tesla can be laminated to obtain a magnetic flux density of 2 tesla. Even in that case, when the outer peripheral side having a cylindrical curved surface is placed as the grounding portion as shown in FIG. 2D, the amount of abrasive grains 6 covering the metal scrap adsorbing means 9 is small. In the polishing process, the inflow of the abrasive grains 6 into the mixed liquid flow pipe 5 is not hindered. On the other hand, when the flat side of the cylinder shape is installed as the ground contact portion as shown in FIG. 2 (e), the amount of abrasive grains 6 covering the metal scrap adsorbing means 9 becomes large and is adsorbed by the metal scrap adsorbing means 9. The interaction with the metal scrap 10 works to prevent the abrasive grains 6 from flowing into the mixed liquid flow pipe 5.

0.5% of a rust preventive is added to water for the purpose of preventing rust on the hollow portion 2 of the mold in the abrasive mixed liquid, and at the same time, this becomes a rust preventive for a strong permanent magnet which is a metal scrap adsorbing means 9. Further, when the piston 4b arranged in the hydraulic pressure generating cylinder 4c, which is the hydraulic pressure generating means 4, is used with water, the packing 4b-1 is worn. Therefore, to prevent this, 3% of lubricant is added to the water.

Using the above-mentioned polishing material mixed liquid polishing apparatus 1 of the present embodiment, the inner side surface 2c of the mold hollow portion 2 is polished as follows according to the polishing method using the polishing material mixed liquid of the present invention.
One of the pair of storage tanks 3 connected to each of the one opening 2a and the other opening 2b of the mold hollow portion 2 is increased in pressure, and the abrasive mixed liquid is forcibly flowed into the flow path of the mold hollow portion 2. The abrasive mixed liquid that has been forcibly flowed in is returned to the other storage tank 3. By alternately increasing the pressure of the pair of storage tanks 3 in this way, the abrasive mixed liquid reciprocates in and out of the flow path of the mold hollow portion 2, and the inner side surface 2c of the mold hollow portion 2 is polished by the abrasive grains 6. To.

In the above process, the abrasive grains 6 stored in the vicinity of the bottom 3a of the storage tank 3 on the hydraulic pressure generation side are provided so as to extend the tip to the vicinity of the bottom 3a of the storage tank 3 on the hydraulic pressure generation side as the hydraulic pressure is generated. The diagonally cut tip 5a of the mixed liquid flow pipe 5 efficiently flows into the flow path of the mold hollow portion 2 through the mixed liquid flow pipe 5, and the inner side surface 2c of the mold hollow portion 2 is polished. do.

On the other hand, the abrasive mixed liquid that has passed through the mold hollow portion 2 flows into the storage tank 3 on the decompression side via the mixing liquid flow pipe 5 attached to the storage tank 3 on the decompression side. Further, the abrasive mixed liquid that has flowed into the storage tank 3 on the decompression side flows into the hydraulic pressure generating cylinder 4c on the decompression side via the abrasive grain separating means 8 and the liquid flow path 7 on the decompression side.
At that time, the abrasive grains 6 in the abrasive mixed liquid are separated by the abrasive grain separating means 8 and flow into the liquid flow path 7 on the reduced pressure side and the hydraulic pressure generating cylinder 4c on the reduced pressure side communicating with the abrasive grain separating means 8. There is no.
Further, the metal scraps 10 inevitably generated by polishing the inner side surface 2c of the mold hollow portion 2 flow into the storage tank 3 on the decompression side together with the abrasive mixed liquid, settle in the storage tank 3, and adsorb the metal scraps. It is adsorbed by means 9.

FIG. 9 shows the abrasive material mixed liquid polishing apparatus 21 of another embodiment of the present invention. In the present embodiment, the storage tank 3 of the previous embodiment is connected to the mold hollow portion 2 by the liquid flow path 7, and the first storage tank 22 and the liquid flow path 7 are used. It is composed of a second storage tank 23 that is connected and is connected to the hydraulic pressure generating means 4 and the liquid flow path 7, and the abrasive grain separating means 8 is housed in the second storage tank 23.
According to the abrasive mixed liquid polishing apparatus 21 of this embodiment, the abrasive grains are contained in the second storage tank 23 in which the concentration of the abrasive grains 6 is reduced as compared with the first storage tank 22 in which the abrasive grains 6 are stored. As a result of accommodating the separating means 8, early clogging of the abrasive grain separating means 8 can be prevented, and the cycle time of the polishing method using the abrasive mixed liquid can be improved.

FIG. 10 shows the abrasive material mixed liquid polishing apparatus 31 of another embodiment of the present invention. In the present embodiment, a plurality of abrasive grain separating means 8 are housed in the storage tank 3 of the previous embodiment, and the number of liquid flow paths 7 from the hydraulic pressure generating cylinder 4c is increased accordingly. As a result, the diameter of the liquid flow path 7 can be substantially increased, and the flow pressure for forcibly flowing the abrasive mixed liquid into the flow path of the mold hollow portion 2 can be increased. Ideally, the diameter of the liquid flow path 7 should be substantially increased, and the diameter thereof should be reduced in the vicinity of the hollow portion 2 of the mold, which is effective in improving the polishing efficiency.

1 ... Abrasive mixed liquid polishing device, 2 ... Mold hollow part, 3 ... Storage tank, 6 ... Abrasive grains, 5 ... Mixed liquid flow pipe, 8 ... Abrasive grain separation Means, 9 ... Metal scrap adsorption means.

Claims (9)

A pair of abrasive mixed liquid storage tanks connected to one opening and the other opening of the mold hollow portion formed in communication with the inside of the mold, and the internal pressure of the pair of storage tanks are alternately increased. In a polishing material mixed liquid polishing apparatus having a hydraulic pressure generating means and in which the inner surface of the hollow portion of the mold is polished by the reciprocating inflow and outflow of the mixed liquid of the abrasive material from the inner surface of the hollow portion of the mold, the pair. An abrasive mixed liquid flow pipe and a laminated wire mesh filter that separates abrasive grains from the abrasive mixed liquid are arranged inside each of the storage tanks of the above, and the tip of the abrasive mixed liquid flow pipe extends to the vicinity of the bottom of the storage tank. An abrasive mixed liquid polishing apparatus, which is attached to one opening in the storage tank in an extended manner and the laminated wire mesh filter is attached to another opening in the storage tank. The abrasive material mixed liquid polishing apparatus according to claim 1, wherein the pair of storage tanks are placed on an iron frame and a strong permanent magnet is arranged inside the storage tank. The abrasive material mixed liquid polishing apparatus according to claim 1, wherein the tip extending to the vicinity of the bottom of the storage tank of the abrasive material mixed liquid flow pipe is cut diagonally. The laminated wire mesh filter is formed by laminating a relatively dense wire mesh filter and a relatively coarse wire mesh filter, with the dense wire mesh filter on the outside and the coarse metal filter on the inside and one end as an opening. The abrasive material mixed liquid polishing apparatus according to claim 1, further comprising a tubular shape having the other end as a closing portion. A wire mesh filter that is coarser than the dense wire mesh filter and denser than the coarse wire mesh filter is laminated between the relatively dense wire mesh filter and the relatively coarse wire mesh filter. The abrasive material mixed liquid polishing apparatus according to claim 4. The abrasive mixed liquid polishing apparatus according to any one of claims 1 to 5, wherein the abrasive mixed liquid is obtained by adding a rust preventive to water and further adding a lubricant. The storage tank is connected to a first storage tank connected to the mold hollow portion by a liquid flow path, and is connected to the first storage tank by a liquid flow path and is connected to the hydraulic pressure generating means by a liquid flow path. The abrasive material mixed liquid polishing apparatus according to any one of claims 1 to 6, wherein the laminated wire mesh filter is housed in the second storage tank. It is applied to the abrasive material mixed liquid polishing apparatus according to any one of claims 1 to 7, and is formed by laminating a relatively dense wire mesh filter and a relatively coarse wire mesh filter, wherein the dense wire mesh filter is formed. A laminated wire mesh filter for abrasive grain separation of an abrasive mixed liquid polishing apparatus characterized in that the wire mesh filter is on the outside, the coarse metal filter is on the inside, one end is an opening, and the other end is a closing portion. .. A wire mesh filter that is coarser than the dense wire mesh filter and denser than the coarse wire mesh filter is laminated between the relatively dense wire mesh filter and the relatively coarse wire mesh filter. The laminated wire mesh filter for separating abrasive grains of the abrasive material mixed liquid polishing apparatus according to claim 8.

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