JP2004160641A - Water jet polishing material recovery device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water jet polishing material recovery device capable of suitably recovering only a polishing material having a particle diameter desirable for reuse from a mixture of the polishing material and a machining liquid used in a water jet cutting machine, and capable of suitably reducing the running cost of the water jet cutting machine. <P>SOLUTION: The mixture or a stock solution of the polishing material and the machining liquid after being used is roughly separated into the solid and the liquid by a cyclone filter 6, the solid (separated polishing material) after separation is dried by a drier 7, and is fed to a screening machine 10. The screening machine 10 is provided with a mesh 11 of 840 μm on an upper part and a mesh 12 of 60 μm on a lower part. The recovered polishing material passing the mesh 11 and remaining on the mesh 12 is fed to the water jet cutting machine 1 as the reusable polishing material. The particle having a diameter less than 60 μm is too fine to be reused, and the particle having a diameter larger than 840 μm can be cut chips or dust, and thereby they are removed respectively. <P>COPYRIGHT: (C)2004,JPO

Description

  The present invention relates to a water-jet abrasive collecting apparatus for collecting an abrasive and a working fluid used in a water-jet cutting machine and reusing at least the above-mentioned abrasive.

  2. Description of the Related Art Conventionally, there has been known a water jet cutting machine that cuts a workpiece by injecting an abrasive such as garnet particles from a nozzle together with a processing liquid such as water and spraying the workpiece onto a workpiece fixed on a work table. . When such a cutting process is performed, a part of the abrasive is broken into fine particles. For this reason, conventionally, the abrasive once used for the cutting process cannot be reused, and all of the abrasive has been treated as industrial waste.

However, abrasives such as garnet grains are expensive, and their inability to be reused as described above has led to an increase in the running cost of the water jet cutting machine. In view of this, it has been considered to separate and collect a large-particle-size abrasive from a used abrasive using a mesh conveyor or the like, and to reuse the abrasive as an abrasive (for example, see Patent Document 1).
JP-A-5-245758 (paragraphs 0016-0017)

  However, in the above-mentioned conventional method, since the abrasive is placed on a mesh conveyor in a wet state, it is not possible to satisfactorily separate only the abrasive having a desired particle size because the abrasive particles adhere to each other. In addition, in the above-described conventional method, all particles having a predetermined particle size or more are collected, so that there is a case where the collected particles include cutting waste or dust.

  Furthermore, in the above-mentioned conventional method, all the remaining particles and the processing liquid that have collected the abrasive having a large particle diameter are discarded. That is, no consideration is given to reusing the working fluid, and the running cost of the water jet cutting machine cannot be sufficiently reduced in this regard. In order to reuse the working fluid, it is necessary to sufficiently remove impurities, and if this condition is not satisfied, there is a possibility that troubles such as clogging of a high-pressure pump of the water jet cutting machine may occur.

  Therefore, the present invention provides a water jet cutting machine that collects only a reusable abrasive having a desired particle size from a mixture of the abrasive and the working fluid used in the water jet cutting machine. An object of the present invention is to provide a water jet abrasive recovery device capable of favorably reducing running costs. Further, in addition to the above objects, the inventions according to claims 2 to 5 have been made with a further object of reducing the running cost of the water jet cutting machine by satisfactorily reusing the working fluid.

  The invention according to claim 1, which has been made to achieve the above object, is to recover an abrasive and a working fluid used in a water jet cutting machine, and to recover at least a water jet abrasive to reuse the abrasive. An apparatus, comprising: a solid-liquid separation unit for roughly separating the mixture of the used abrasive and the working liquid into a solid and a liquid; a drying unit for drying a solid separated by the solid-liquid separation unit; Sieving means for sieving the solid content dried by the means, and collecting particles having a first predetermined particle size or less and a second predetermined particle size or more as a reusable abrasive. And

  In the present invention configured as described above, the abrasive and the working liquid used in the water jet cutting machine are roughly separated into solid and liquid by the solid and liquid separating means, and the solid content therein is dried by the drying means. As a result, the particles that have adhered to each other via the processing liquid are separated. For this reason, when the dried solid is subsequently sieved by the sieving means, each particle can be sieved satisfactorily according to the actual particle size of each particle. The sieving means collects particles having a size equal to or smaller than the first predetermined particle size and equal to or larger than the second predetermined particle size as a reusable abrasive. That is, particles having a particle size smaller than the second predetermined particle size are excluded as particles that cannot be reused due to cracking and miniaturization, and particles having a particle size larger than the first predetermined particle size are excluded because there is a possibility that they are cutting waste or dust. You.

  According to a second aspect of the present invention, in addition to the configuration of the first aspect, the drying means condenses steam generated when the solids are dried to form a working fluid that can be reused by the water jet cutting machine. It is characterized by further comprising condensing means.

  In the present invention, the steam generated during the drying by the drying unit is condensed by the condensing unit, and the working fluid can be reused by the water jet cutting machine. When the vapor is condensed in this manner, the vapor hardly contains impurities and can be satisfactorily reused as a working fluid. Moreover, in the present invention, since the steam generated by the drying means is condensed, the running cost and the production cost of the water jet abrasive recovery device itself can be favorably reduced as compared with a case where a distillation device or the like is separately provided. .

  According to a third aspect of the present invention, in addition to the configuration of the first or second aspect, the liquid separated by the solid-liquid separating means is finely filtered, and a processing fluid reusable by the water jet cutting machine is provided. And a filtering means for filtering.

  In the present invention, the liquid separated by the solid-liquid separating means can be finely filtered by the filtering means to obtain a working liquid which can be reused by the water jet cutting machine. When the microfiltration is performed as described above, the filtered liquid can be satisfactorily reused as a processing liquid. In addition, since the liquid component is a residue obtained by roughly removing the solid component by the solid-liquid separation means, microfiltration is extremely easy.

  According to a fourth aspect of the present invention, in addition to the configuration of the second aspect, a first tank for storing the liquid separated by the solid-liquid separating means, and the liquid stored in the first tank are provided. A second tank for storing the combined filtration liquid, which is subjected to precision filtration and converted into a processing liquid reusable by the water jet cutting processing machine, and the processing liquid condensed by the condensation means and the processing liquid filtered by the filtration means. And wherein the filtering means filters the liquid stored in the first tank only when the second tank is not full.

  In the present invention, the liquid component separated by the solid-liquid separation device is temporarily stored in the first tank, and the liquid component is finely filtered by the filtration device to obtain a processing liquid that can be reused by the water jet cutting machine. be able to. When the microfiltration is performed in this manner, the filtered liquid can be reused as a working fluid as well as the working fluid condensed by the condensing means. In addition, since the liquid component is a residue obtained by roughly removing the solid component by the solid-liquid separation means, microfiltration is extremely easy.

  Further, the working fluid condensed by the condensing means and the working fluid filtered by the filtering means are stored in accordance with the second tank, and only when the second tank is not full, the filtering means enters the first tank. Filter the stored liquid. That is, by providing the first tank and the second tank and controlling the operation of the filtration means in this way, in the present invention, the above two means (condensing means, filtration means) for reusing the working fluid It is also possible to satisfactorily prevent excessive supply of the working fluid while using the same.

  According to a fifth aspect of the present invention, in addition to the configuration of the third or fourth aspect, the backwash water generated by the filtering means is separated into the solid and liquid by the abrasive and the working fluid used in the water jet cutting machine. It is characterized by being introduced into the means.

  In the present invention, the backwash water generated by the filtration means is introduced into the solid-liquid separation means together with the abrasive and the working liquid used in the water jet cutting machine. Therefore, a reusable working fluid can be obtained from the backwash water, and the running cost of the water jet cutting machine can be reduced more favorably than in a case where all the backwash water is discarded. it can.

  According to the first aspect of the present invention, it is possible to satisfactorily collect only the abrasive having a desired particle size that can be reused, and thus to satisfactorily reduce the running cost of the water jet cutting machine. . The first predetermined particle size and the second predetermined particle size are appropriately set according to the performance of the water jet cutting machine, the particle size of the abrasive suitable for the water jet cutting machine, and the like.

  According to the second aspect of the present invention, in addition to the effect of the first aspect, the working fluid can be well reused without increasing the running cost and manufacturing cost of the water jet abrasive recovery apparatus itself. There is an effect that the running cost of the jet cutting machine can be further reduced.

  According to the third aspect of the invention, in addition to the effects of the first or second aspect, the working fluid can be reused very easily and well, and the running cost of the water jet cutting machine can be extended. Is more effectively reduced.

  According to a fourth aspect of the present invention, in addition to the effect of the second aspect of the invention, the water jet cutting machine is further satisfactorily reused of the machining fluid while preventing excessive supply of the machining fluid. In this case, the running cost can be further reduced.

  According to the fifth aspect of the invention, in addition to the effects of the third or fourth aspect, the running fluid of the water jet cutting machine can be more favorably reduced by reusing the working fluid more favorably. The effect occurs.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory view schematically showing a configuration of a water jet abrasive recovery apparatus to which the present invention is applied. The water jet cutting machine 1 in FIG. 1 cuts a workpiece by spraying garnet grains as an abrasive together with water as a processing liquid from a nozzle (not shown) and spraying the workpiece onto a work fixed on a work table. It is to be processed. The water jet abrasive recovery apparatus according to the present embodiment recovers a mixture (hereinafter, referred to as a stock solution) of garnet particles and water used for the cutting process by the following configuration, and reuses the mixture as the abrasive and the processing fluid. It is a device for performing.

  As shown in FIG. 1, the present apparatus is provided with a stock solution pit 2 for collecting and storing stock solution sent from a water jet cutting machine 1. Further, in the stock solution pit 2, a stock solution supply pump 3 for pumping the stock solution, a level gauge 2a for detecting the minimum water level of the stock solution so that the stock solution supply pump 3 can be driven stably, and the water level of the stock solution is almost full. A level gauge 2b is provided for detecting the fact. In the following description, the detection signals of the level gauges 2a and 2b are LC1 and LC2, and the detection signals are OFF when the liquid level of the undiluted liquid is lower than the above-mentioned water level, and are ON when the liquid level of the undiluted liquid is above the above-mentioned water level.

  The undiluted solution pumped by the undiluted solution supply pump 3 is sent to a cyclone filter 6 as solid-liquid separation means via a flow meter 4 and an electric valve 5. The cyclone filter 6 roughly separates the undiluted solution by the centrifugal effect of apparently 500 G, and the separated abrasive as a solid after separation is sent to the dryer 7 as drying means.

  The dryer 7 sends city water (tap water or well water) to a drain recovery device 72 together with steam drain via a soft water device 71, and heats it by a steam boiler 73 to heat and dry an object by steam obtained. It is well known. Further, in the dryer 7, various unnecessary waters including the discarded steam drain are discharged to the side grooves 74.

  The dried abrasive obtained by drying the separated abrasive by the dryer 7 is sent to a sieving machine 10 as sieving means. The sieving machine 10 is provided with a mesh 11 for sieving particles larger than 840 μm in an upper stage and a mesh 12 for sieving particles of 60 μm or more in a lower stage, and is vibrated by an electric actuator. The abrasive remaining on the upper side is sent to the water jet cutting machine 1 as a reusable recovered abrasive. On the other hand, particles having a particle size larger than 840 μm and remaining on the mesh 11 and particles having a particle size smaller than 60 μm and passing through the mesh 12 are discarded in the sludge receiver 13. That is, particles smaller than 60 μm (corresponding to the second predetermined particle size) are excluded as garnet particles that cannot be reused because they are cracked and refined, and particles larger than 840 μm (corresponding to the first predetermined particle size) are cut off. Or garbage, which is excluded.

  Vapor (steam) generated by the drying by the dryer 7 is collected by a fan 14 and sent to a condenser 17 as condensation means via a filter 15 and a vacuum adjustment indicator 16. Cooling water is supplied to the condenser 17 from a cooling tower 19 by a cooling water circulation pump 18. The vapor condenses here and is sent as a condensed liquid to a recycled water receiving tank 21 as a second tank.

  In addition, thermometers 17a and 17b are provided at the inlet and outlet of the condenser 17 in the flow path of the cooling water. The recycle water receiving tank 21 is provided with a level gauge 21a that generates a detection signal (hereinafter, referred to as LC4) that changes between L, H, and HH according to the water level. Here, when the detection signal LC4 is L, it indicates that there is almost no liquid in the recycled water receiving tank 21, H indicates that the recycled water receiving tank 21 is almost full, and HH indicates that it is full. Represents.

  On the other hand, the separated water as the liquid after the solid-liquid separation by the cyclone filter 6 is sent to the separated water receiving tank 22 as the first tank. The separated water receiving tank 22 is provided with a level gauge 22a that generates a detection signal (hereinafter, referred to as LC3) that changes between L, H, and HH in accordance with the water level. To the microfiltration device 24 as filtration means. The meaning of L, H, HH of the detection signal LC3 is the same as that of the detection signal LC4.

  The microfiltration device 24 removes a substance having a size of 10 μm or more using an MF membrane (microfilter membrane). The filtered water that has passed through the microfiltration device 24 is stored in the recycle water receiving tank 21 together with the condensate described above. The condensed liquid and the filtered water stored in the recycled water receiving tank 21 are recycled as recycle water as a processing liquid in the water jet cutting machine 1 via a recycled water transfer pump 25 and an electric valve 26. Sent to 1. On the other hand, backwash water generated in the microfiltration device 24 is introduced into the stock solution pit 2.

  As described above, in the water jet abrasive recovery apparatus of the present embodiment, the stock solution is roughly separated into solid and liquid by the cyclone filter 6, and the solid component (separated abrasive) is dried by the dryer 7. As a result, the particles that have adhered to each other via the processing liquid are separated. For this reason, when the dry abrasive obtained by drying the separated abrasive in the dryer 7 is sieved by the sieving machine 10, each particle is sieved well according to the actual particle size of each particle. be able to. Further, in the sieving machine 10, particles having a size of 60 μm or more and 840 μm or less are sieved as a reusable recovered abrasive, so that garnet grains that are cracked and refined, cut waste, dust and the like can be satisfactorily removed. Therefore, in the present embodiment, it is possible to satisfactorily collect only the reusable abrasive having a desired particle size, and thus to reduce the running cost of the water jet cutting machine 1 satisfactorily. .

  Further, in the present embodiment, the vapor generated by the dryer 7 is condensed into condensate, and the liquid (separated water) in the solid-liquid separation roughly performed by the cyclone filter 6 is subjected to precision filtration to obtain filtered water. These are supplied to the water jet cutting machine 1 as recyclable water that can be reused as a working fluid. For this reason, the working fluid can also be satisfactorily reused, and the running cost of the water jet cutting machine 1 can be further reduced.

  In the present embodiment, since the vapor generated by the dryer 7 is condensed into condensed liquid, a processing liquid containing almost no impurities can be obtained at low cost. Further, in the present embodiment, since the cyclone filter 6 roughly performs the fine filtration on the residue after removing the solid content, the microfiltration is extremely easy, and filtered water that can be suitably reused as a working fluid is obtained. Further, in this embodiment, since the backwash water generated by the microfiltration device 24 is introduced into the stock solution pit 2, a reusable working fluid can be obtained from the backwash water. The running cost of the water jet cutting machine 1 can be reduced more favorably than when all the water is discarded.

  Next, in the water jet abrasive recovery device of the present embodiment, a control device (not shown) controls the driving state of each unit based on the detection signals LC1 to LC4 generated by the level gauges 2a, 2b, 22a, and 21a. are doing. Next, the drive control performed by the water jet abrasive recovery device will be described with reference to the flowchart of FIG. The control device starts this processing when the operator instructs the processing of the undiluted solution.

  As shown in FIG. 2, when the process is started, the control device determines whether or not LC1 is ON in S1 (S represents a step: the same applies hereinafter). When LC1 is OFF (S1: NO), since there is almost no stock solution in stock solution pit 2, it stands by while repeating S1 as it is. When LC1 = ON because the stock solution is sent from the water jet cutting machine 1 (S1: YES), it is determined in subsequent S3 whether LC3 is equal to or lower than HH. Normally, LC3 is less than H at the start of the control (see S13 and S19 described later), so here the affirmative determination is made and the process proceeds to S5 to operate the stock solution supply pump 3.

  When the stock solution supply pump 3 is operated (S5), the separated water is supplied to the separated water receiving tank 22, and the separated abrasive is supplied to the dryer 7. Therefore, in S7, it is determined whether or not the operation of the dryer 7 is ready, such as storing one batch of separated abrasives in the dryer 7. If one batch of separated abrasives is not stored in the dryer 7 and the operation is not ready (S7: NO), the process returns to S1 to repeat the above processing. Further, if LC3 becomes HH during the repetition of this process (S3: NO), the separated water cannot be sent to the separated water receiving tank 22 any more, so the process returns to S1 without shifting to S5, and returns to S1 and S3. Wait in loop processing.

  On the other hand, when the preparation for the operation of the dryer 7 is completed while repeating the above processing (S7: YES), it is determined in S9 whether or not the LC4 is equal to or lower than HH. If LC4> HH (S9: NO), the process waits while repeating the determination of S9, and if LC4 ≦ HH (S9: YES), the process proceeds to S11. Since the water level in the recycle water receiving tank 21 decreases due to the consumption of the recycle water in the water jet cutting machine 1, even if a negative determination is made in S9, normally, after a short wait, LC4 ≦ HH ( S9: YES), the process proceeds to S11.

  In S11, the operation of the dry separation process according to another routine is started. That is, after sufficient drying is performed by the dryer 7, a process of sieving the obtained dry abrasive with the sieving machine 10 is started. Further, when the operation of the drying / separating step is started, the fan 14 is also driven at the same time, and the condensate is supplied to the recycled water receiving tank 21.

  In S13 following S11, it is determined whether or not LC3 is higher than H. If LC3 <H (S13: NO), the process is temporarily terminated. In this case, when the operation processing of the drying / separating step by the above-mentioned separate routine is completed for one batch, the processing of the entire water jet abrasive recovery apparatus is temporarily ended.

  On the other hand, if LC3 ≧ H (S13: YES), it is determined whether or not LC4 is HH or less (S15). If LC4 ≦ HH (S15: YES), the separated water transfer pump 23 Is driven (S17). By this processing, the separated water in the separated water receiving tank 22 is finely filtered by the fine filtration device 24 and then sent to the recycled water receiving tank 21. By this processing, the water level in the separated water receiving tank 22 decreases. Therefore, in S19 following S17, it is determined whether or not LC3 ≧ H as in S13. If LC3 ≧ H (S19: YES), the process proceeds to S15. Then, if LC3 <H during the processing of S15 to S19 is repeated (S19: NO), the processing is terminated.

  Further, if LC4> HH during the processing of S15 to S19 is repeated (S15: NO), since the filtered water cannot be sent to the recycled water receiving tank 21 any more, the process stands by while repeating the determination of S15. As described above, the water level in the recycle water receiving tank 21 is reduced by the consumption of the recycle water in the water jet cutting machine 1, so that it is normally LC4 ≦ HH after waiting for a while (S15: YES), and S15 to S19. Loop processing is restarted. Finally, LC3 <H (S19: NO), and the process ends.

  When the above processing is performed, the water jet abrasive can be satisfactorily recycled one batch at a time. In the above process, the machining fluid is recycled by the microfiltration only when LC4 is equal to or lower than HH. Therefore, the condenser 17 and the microfiltration device 24 are used in combination to efficiently recycle the machining fluid while recycling. It is also possible to satisfactorily prevent excessive supply of the processed working fluid.

  Note that the present invention is not limited to the above-described embodiment at all, and can be implemented in various forms without departing from the gist of the present invention. For example, in the above embodiment, the abrasive is collected by so-called batch processing in which one batch of separated abrasive is accumulated in the dryer 7 and then a drying / separating step is performed. When a machine is used, the abrasive can be recovered by continuous processing.

  As the solid-liquid separation means, a centrifuge, a water ratio, or the like can be used in addition to the cyclone filter. As the drying means, it is desirable to apply vibration in the drying step, but in addition to the dryer 7 using steam as in the above embodiment, a dryer using ultrasonic waves, a dryer using sunlight, and the like are also available. Can be used. As the filtration means, a simple filtration device using a cartridge filter, a centrifugal separator, or the like can be used in addition to a precision filtration device using an MF membrane. Further, a centrifugal separator may be provided in front of the microfiltration device 24, and the separated water may be microfiltered after removing the fine particles by the centrifuge. In this case, the load of the microfiltration is reduced.

  Still further, the roughness of the meshes 11 and 12 in the sieving machine 10 can be variously changed as desired by the operator. For example, the mesh 11 may have a roughness of 590 μm, the mesh 12 may have a roughness of 300 μm, the mesh 11 may have a roughness of 300 μm, the mesh 12 may have a roughness of 150 μm, and the mesh 11 may have a roughness of 210 μm. May be 105 μm, the mesh 11 may have a roughness of 150 μm, the mesh 12 may have a roughness of 74 μm, and the mesh 11 may have a roughness of 145 μm and the mesh 12 may have a roughness of 44 μm.

It is an explanatory view showing roughly composition of a water jet abrasive collection device to which the present invention is applied. It is a flowchart showing the drive control performed in the water jet abrasive collection device.

Explanation of reference numerals

DESCRIPTION OF SYMBOLS 1 ... Water jet cutting machine 2 ... Stock solution pits 2a, 2b, 21a, 22a ... Level gauge 3 ... Stock solution supply pump 6 ... Cyclone filter 7 ... Dryer 10 ... Sieving machine 17 ... Condenser 21 ... Recycled water receiving tank 22 ... Separated water Receiving tank 23 ... Separated water transfer pump 24 ... Microfiltration device 25 ... Recycled water transfer pump

Claims (5)

A water jet abrasive recovery device for recovering the abrasive and the working fluid used in the water jet cutting machine, at least for reusing the abrasive,
The mixture of the abrasive and the working fluid used above, solid-liquid separation means for roughly solid-liquid separation,
Drying means for drying the solids separated by the solid-liquid separation means,
Sieving means for sieving the solid content dried by the drying means, and recovering particles having a first predetermined particle size or less and a second predetermined particle size or more as a reusable abrasive;
A water jet abrasive recovery device comprising: The condensing means, wherein the drying means condenses the steam generated during the drying of the solid content to make the working fluid reusable in the water jet cutting machine,
The water jet abrasive recovery device according to claim 1, further comprising: Filtration means to finely filter the liquid separated by the solid-liquid separation means, and a reusable working liquid in the water jet cutting machine,
3. The water jet abrasive recovery device according to claim 1, further comprising: A first tank for storing the liquid separated by the solid-liquid separation means,
Filtration means for subjecting the liquid component stored in the first tank to fine filtration to obtain a processing liquid reusable by the water jet cutting machine;
A second tank that stores the working fluid condensed by the condensing means and the working fluid filtered by the filtration means,
Further comprising
3. The water jet abrasive recovery device according to claim 2, wherein the filtering means filters the liquid stored in the first tank only when the second tank is not full. 5. The water jet polishing according to claim 3, wherein the backwash water generated by the filtration means is introduced into the solid-liquid separation means together with the abrasive and the working liquid used in the water jet cutting machine. Material recovery device.

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