Adjustment device, adjustment method, and manufacturing method

Abstract

This adjustment device (10) comprises: a container (12) having a liquid inflow part (18) and a liquid outflow part (20); and a porous filter (14) that supplies a liquid from the liquid inflow part (18) to the liquid outflow part (20) via pores. Solid metal particles are captured in the pores. The porous filter (14) increases the specific resistance value of the liquid after passing through the pores to be greater than the specific resistance of the liquid before passing through the pores.

Description

Adjustment device, adjustment method, and manufacturing method

[0001] The present invention relates to adjusting the resistivity of a liquid containing metal ions.

[0002] It has been known for some time that there are various applications requiring liquids with low metal ion content.

[0003] For example, Japanese Patent Application Laid-Open Publication No. 2013-132735 discloses a wire electric discharge machine that uses an ion exchange resin to maintain the resistivity of the machining fluid higher than a predetermined value and reduce the ion concentration in the machining fluid. Ion exchange resins are used in a variety of fields, not just wire electric discharge machines. For example, ion exchange resins are used in semiconductor manufacturing, alcohol production, pharmaceutical manufacturing, pure water treatment, sewage treatment, power generation treatment, calcium removal treatment in boilers, sugar refining, etc.

[0004] Furthermore, for example, Japanese Patent Application Laid-Open No. 2019-98225 discloses a water purification system that insolubilizes metal ions in water and removes the insolubilized metal components from the water by filtration.

[0005] Furthermore, for example, Japanese Patent Application Laid-Open No. 2005-213200 discloses a removal device that removes metal compounds from surfactants using an apparatus in which an ion exchange resin packed column and a functional filter unit are connected by components made of a specific material.

[0006] Furthermore, for example, Japanese Patent Application Laid-Open No. 2006-95391 discloses a wastewater treatment device for treating wastewater containing metal ions.

[0007] However, in the cases of JP 2013-132735 A and JP 2005-213200 A, replacement of the ion exchange resin is required. Furthermore, in the case of JP 2019-98225 A, an insolubilizer is required to insolubilize the metal ions. Therefore, the running costs for adjusting the resistivity of the metal ions tend to increase. Therefore, there has been a demand for reducing the metal ion concentration in a liquid without using an ion exchange resin or an insolubilizer.

[0008] The present invention aims to solve the above-mentioned problems.

[0009] A first aspect of the present invention is an adjusting device for adjusting the resistivity of a liquid that does not contain solid metal objects but contains metal ions, comprising a container having a liquid inlet and a liquid outlet, and a porous filter housed in the container and supplying the liquid from the liquid inlet to the liquid outlet through pores, wherein solid metal particles are captured in the pores, and the porous filter increases the resistivity of the liquid after passing through the pores compared to the resistivity of the liquid before passing through the pores.

[0010] A second aspect of the present invention is a method for adjusting the resistivity of a liquid that does not contain solid metal objects but contains metal ions, in which the liquid is passed through pores of a porous filter in which solid metal particles are captured, thereby making the resistivity of the liquid after passing through the pores larger than the resistivity of the liquid before passing through the pores.

[0011] A third aspect of the present invention is a manufacturing method for manufacturing an adjusting device that adjusts the resistivity value of a liquid that does not contain solid metal objects and contains metal ions, and includes a recovery step (P1) of recovering from a machine tool a filter that removes machining debris generated by machining an object to be machined by the machine tool, and a storage step (P2) of storing the filter in a container having an inlet and an outlet for the liquid.

[0012] According to the above aspect, the metal ion concentration of the liquid can be reduced without using an ion exchange resin or an insolubilizing agent.

[0013] Fig. 1 is a schematic diagram showing the configuration of an adjustment device according to an embodiment. Fig. 2 is a flowchart showing the flow of a manufacturing method for manufacturing an adjustment device. Fig. 3 is a schematic diagram showing the configuration of an adjustment device according to a modified example. Fig. 4 is a flowchart showing the flow of an adjustment method according to a modified example.

[0014] 1 is a schematic diagram showing the configuration of a conditioning device 10 according to an embodiment. The conditioning device 10 includes a container 12 and a porous filter 14.

[0015] The container 12 is a container that houses the porous filter 14. The container 12 has a container body portion 16, a liquid inlet portion 18, and a liquid outlet portion 20.

[0016] The container body 16 has a filter housing space FS therein. The filter housing space FS is a space capable of housing the porous filter 14. The container body 16 may have an open / close lid for housing the porous filter 14 in the filter housing space FS. The container body 16 may also be separable into multiple pieces for housing the porous filter 14 in the filter housing space FS.

[0017] The liquid inlet 18 communicates with the filter housing space FS. The liquid inlet 18 has a water inlet hole 18-1 and a water inlet conduit 18-2. The water inlet hole 18-1 is a hole that penetrates the container body 16 from the outer wall to the inner wall of the container body 16. The water inlet conduit 18-2 is a conduit that covers the outside of the water inlet hole 18-1 and extends outward from the outer wall surface of the container body 16. The water inlet conduit 18-2 may be formed integrally with the container body 16, or may be joined to the container body 16 by a joining member. Alternatively, the water inlet conduit 18-2 may be removed.

[0018] The liquid outflow section 20 communicates with the filter housing space FS. The liquid outflow section 20 has a water outlet hole 20-1 and a water outlet conduit 20-2. The water outlet hole 20-1 is a hole that penetrates the container body 16 from the outer wall of the container body 16 to the inner wall of the container body 16. The water outlet conduit 20-2 is a conduit that covers the outside of the water outlet hole 20-1 and extends outward from the outer wall surface of the container body 16. The water outlet conduit 20-2 may be formed integrally with the container body 16, or may be joined to the container body 16 by a joining member. The water outlet conduit 20-2 may also be removed.

[0019] The porous filter 14 is a porous body having pores. Examples of porous bodies include filter paper and filter cloth. Solid metal particles are trapped in the pores. The metal particles include at least one of iron, aluminum, copper, zinc, cemented carbide, tungsten, molybdenum, carbon, titanium, silicon, manganese, chromium, phosphorus, sulfur, and nickel. The metal particles may be chips generated by machining a workpiece with a machine tool. When the metal particles are chips, the porous filter 14 may be a filtration filter that has been used in the past to remove chips generated by machining a workpiece with a machine tool.

[0020] Machine tools include wire electric discharge machines, die-sinking electric discharge machines, small-hole electric discharge machines, and cutting machines. Wire electric discharge machines are machines that machine workpieces by electric discharges generated in the inter-electrode space between a wire electrode and the workpiece. Die-sinking electric discharge machines are machines that machine workpieces by electric discharges generated in the inter-electrode space between a die-sinking electrode and the workpiece. Small-hole electric discharge machines are machines that machine workpieces by electric discharges generated in the inter-electrode space between a rotating rod electrode with a circular cross section and the workpiece. Cutting machines are machines that machine workpieces using tools.

[0021] The porous filter 14 supplies the liquid from the liquid inlet 18 to the liquid outlet 20 through the pores. If the liquid supplied to the liquid inlet 18 does not contain solid metal objects but does contain metal ions, the resistivity of the liquid after passing through the pores of the porous filter 14 will be greater than the resistivity of the liquid before passing through the pores.

[0022] The adjustment method of the adjustment device 10 involves passing a liquid that does not contain solid metal objects but contains metal ions through the pores of the porous filter 14 in which solid metal particles are captured, thereby increasing the resistivity of the liquid.

[0023] The inventors discovered that passing clean water through the pores of a porous body in which machining chips are trapped increases the resistivity of the clean water. The machining chips are solid metal particles generated by machining an object with a machine tool. Clean water is a liquid from which machining chips have been removed, and contains no solid metal particles but metal ions.

[0024] As described above, this embodiment includes a porous filter 14 in which solid metal particles are trapped in the pores. The porous filter 14 increases the resistivity of a liquid containing metal ions but no solid metal particles after the liquid passes through the pores compared to before the liquid passes through the pores. This allows the metal ion concentration in the liquid to be reduced without using an ion exchange resin or an insolubilizer.

[0025] Fig. 2 is a flowchart showing the flow of a manufacturing method for manufacturing the adjustment device 10. Fig. 2 shows the flow of a manufacturing method in which a filtration filter that was previously used to remove processing debris generated by processing a workpiece with a machine tool is used as the porous filter 14. The manufacturing method for the adjustment device 10 includes a recovery step P1 and a storage step P2.

[0026] The recovery step P1 is a step of recovering a filter from a machine tool. The filter is disposed in a flow path through which wastewater, which is a machining fluid containing machining debris, flows. The filter recovered in the recovery step P1 is a filter that has been used at least once (through which wastewater has flowed).

[0027] The accommodation step P2 is a step of accommodating a filtration filter in the container 12. For example, if the container body 16 has an open / close lid, the filtration filter is accommodated in the filter accommodation space FS of the container body 16 via the open / close lid. Alternatively, for example, if the container body 16 is separable into multiple pieces, the multiple pieces are joined together so that the filtration filter is accommodated in the filter accommodation space FS.

[0028] According to the above manufacturing method, it is possible to manufacture the adjusting device 10 that reduces the metal ion concentration of a liquid without using an ion exchange resin or an insolubilizing agent. In addition, the filtration filter can be recycled as the porous filter 14.

[0029] The conditioning device 10 of this embodiment can be installed in various devices that require a liquid with a low metal ion content. For example, the conditioning device 10 is installed in the wire electric discharge machine, water purification system, or removal device described above, where necessary. The installation method of the conditioning device 10 will be described using a wire electric discharge machine as an example.

[0030] In a wire electric discharge machine, there is a conduit that leads machining fluid from a clean water tank to a machining tank. The clean water tank is a water tank that stores clean water, which is machining fluid from which machining debris has been removed. The machining tank is a water tank that stores machining fluid in which the workpiece is immersed. When an adjustment device 10 is installed in the above conduit, for example, the conduit is divided into an upstream section and a downstream section. The end of the upstream section (downstream end) is connected to a liquid inlet section 18 of the adjustment device 10. Meanwhile, the downstream section (upstream end) is connected to a liquid outlet section 20 of the adjustment device 10.

[0031] When the adjusting device 10 is installed in this manner, the porous filter 14 increases the resistivity of the clean water supplied to the machining tank compared to the resistivity of the clean water supplied from the clean water tank, thereby reducing the metal ion concentration in the machining fluid stored in the machining tank without using an ion exchange resin.

[0032] The reciprocal of the resistivity value [Ωm] is the conductivity [S / m], and there is a correlation between the resistivity value [Ωm] and the conductivity [S / m]. Therefore, the resistivity value [Ωm] can be replaced with the conductivity [S / m]. When the resistivity value [Ωm] is replaced with the conductivity [S / m], the magnitude relationship between the values ​​is reversed. For example, "increasing the resistivity value [Ωm]" is synonymous with "decreasing the conductivity [S / m]."

[0033] [Modifications] The above embodiment may be modified as follows.

[0034] Fig. 3 is a schematic diagram showing the configuration of the adjustment device 10 according to a modified example. In Fig. 3, the same components as those described in the embodiment are denoted by the same reference numerals. Note that in this modified example, descriptions that overlap with the embodiment will be omitted.

[0035] In this modified example, a bypass pipe 22, a switch 24, a resistivity meter 26, and a controller 28 are newly provided.

[0036] The bypass pipe 22 is a pipe that bypasses the porous filter 14 and is connected to the liquid inlet 18 and the liquid outlet 20 .

[0037] The switch 24 is a device that switches the liquid supply destination between the bypass pipeline 22 and the porous filter 14. The switch 24 may be a three-way valve or may have two on-off valves. When the switch 24 is a three-way valve, the three-way valve is provided at a connection point CP between the bypass pipeline 22 and the water inlet pipeline 18-2 of the liquid inlet section 18 (see FIG. 3). When the switch 24 is a two on-off valves, one of the two on-off valves is provided in the water inlet pipeline 18-2 upstream of the connection point CP, and the other of the two on-off valves is provided in the bypass pipeline 22 near the connection point CP.

[0038] The resistivity meter 26 measures the resistivity value of the liquid supplied to the liquid inlet portion 18. The resistivity meter 26 may be provided in the liquid inlet portion 18 or in the liquid supply source. For example, when the adjustment device 10 is installed in an electric discharge machine (a wire electric discharge machine, a die-sinking electric discharge machine, or a small-hole electric discharge machine), the liquid supply source is a clean water tank.

[0039] The controller 28 controls the switch 24. The controller 28 has a processor such as a CPU or an MPU, and one or more memories such as a ROM, a RAM, or a hard disk. The controller 28 compares the resistivity value of the liquid measured by the resistivity meter 26 with a predetermined threshold. If the resistivity value is below the predetermined threshold, the controller 28 controls the switch 24 to switch the liquid supply destination to the porous filter 14. On the other hand, if the resistivity value is equal to or greater than the predetermined threshold, the controller 28 controls the switch 24 to switch the liquid supply destination to the bypass pipeline 22.

[0040] The adjustment method of the adjustment device 10 according to this modification is performed as follows. Fig. 4 is a flowchart showing the flow of the adjustment method according to the modification. The adjustment method according to the modification includes a supplying step P11, a measuring step P12, and a switching step P13.

[0041] The supply step P11 is a step of supplying a liquid containing metal ions but not containing solid metal objects to the switch 24. In this step, for example, an on-off valve provided in a pipeline leading from the liquid supply source to the liquid inlet 18 of the adjustment device 10 is opened.

[0042] The measurement step P12 is a step of measuring the resistivity of the liquid supplied to the liquid inlet portion 18. The resistivity is measured by a resistivity meter 26 provided in the liquid inlet portion 18 or the liquid supply source, etc.

[0043] The switching process P13 is a process of switching the liquid supply destination between the bypass pipeline 22 and the porous filter 14 based on the measurement results. The switching of the liquid supply destination is executed by the controller 28. In this process, if the resistance value is below a predetermined threshold, the liquid supply destination is switched to the porous filter 14. On the other hand, if the resistivity value is equal to or greater than the predetermined threshold, the liquid supply destination is switched to the bypass pipeline 22.

[0044] The supplying step P11, the measuring step P12, and the switching step P13 are each continued from the start of adjustment of the resistivity value of the liquid until the adjustment is completed.

[0045] According to the present modified example described above, liquid can be supplied to the porous filter 14 only when necessary, which improves the life of the porous filter 14 compared to when liquid is constantly supplied to the porous filter 14.

[0046] The resistivity meter 26 of this modified example may be replaced with a conductivity meter. The conductivity meter measures the conductivity of the liquid supplied to the liquid inlet portion 18. When the resistivity meter 26 is replaced with a conductivity meter, the controller 28 compares the conductivity of the liquid measured by the conductivity meter with a predetermined threshold. If the conductivity exceeds the predetermined threshold, the controller 28 controls the switch 24 to switch the supply of the liquid to the porous filter 14. On the other hand, if the conductivity is equal to or lower than the predetermined threshold, the controller 28 controls the switch 24 to switch the supply of the liquid to the bypass pipeline 22.

[0047] [Invention] The invention and its effects that can be understood from the above description will be described below.

[0048] (1) The present invention provides an adjusting device (10) for adjusting the resistivity of a liquid that does not contain solid metal objects but contains metal ions, comprising: a container (12) having a liquid inlet (18) and a liquid outlet (20); and a porous filter (14) housed in the container and supplying the liquid from the liquid inlet to the liquid outlet through pores, wherein solid metal particles are captured in the pores, and the porous filter increases the resistivity of the liquid after passing through the pores compared to the resistivity of the liquid before passing through the pores.

[0049] This allows the metal ion concentration of the liquid to be reduced without using an ion exchange resin or an insolubilizing agent.

[0050] (2) In the adjusting device of the present invention, the metal particles may contain at least one of iron, aluminum, copper, zinc, cemented carbide, tungsten, molybdenum, carbon, titanium, silicon, manganese, chromium, phosphorus, sulfur, and nickel, thereby appropriately increasing the resistivity of a liquid containing metal ions but not containing solid metal objects.

[0051] (3) The present invention is an adjusting device, and the metal particles may be chips generated by machining an object to be machined using a machine tool. This allows the resistivity of a liquid containing metal ions but not containing solid metal objects to be appropriately increased.

[0052] (4) In the adjusting device of the present invention, the porous filter may be a filter that has been used in the past as a filter for removing machining debris generated by machining an object to be machined by a machine tool. This allows the filter to be recycled.

[0053] (5) The present invention may also provide an adjusting device including a bypass conduit (22) that bypasses the porous filter and is connected to the liquid inlet and the liquid outlet; a switch (24) that switches the liquid supply destination between the bypass conduit and the porous filter; a resistivity meter (26) that measures the resistivity of the liquid supplied to the liquid inlet; and a controller (28) that controls the switch to switch the liquid supply destination to the porous filter when the resistivity of the liquid is below a predetermined threshold, and to switch the liquid supply destination to the bypass conduit when the resistivity of the liquid is equal to or greater than the predetermined threshold. This allows liquid to be supplied to the porous filter only when necessary, thereby improving the life of the porous filter compared to when liquid is constantly supplied to the porous filter.

[0054] (6) The present invention provides a method for adjusting the resistivity of a liquid that does not contain solid metal objects but contains metal ions, by flowing the liquid through the pores of a porous filter in which solid metal particles are captured, thereby making the resistivity of the liquid after passing through the pores larger than the resistivity of the liquid before passing through the pores.

[0055] This allows the metal ion concentration of the liquid to be reduced without using an ion exchange resin or an insolubilizing agent.

[0056] (7) The present invention provides an adjustment method including a measurement step (P12) of measuring the resistivity of the liquid supplied to the porous filter, and a switching step (P13) of switching the supply destination of the liquid between a bypass line bypassing the porous filter and the porous filter based on the measurement results. In the switching step, the supply destination of the liquid may be switched to the porous filter when the resistivity of the liquid is below a predetermined threshold, and may be switched to the bypass line when the resistivity of the liquid is equal to or greater than the predetermined threshold. This allows the liquid to be supplied to the porous filter only when necessary. Therefore, the life of the porous filter can be improved compared to when the liquid is constantly supplied to the porous filter.

[0057] (8) The present invention provides a manufacturing method for manufacturing an adjusting device for adjusting the resistivity value of a liquid containing metal ions and not containing solid metal objects, the method including a recovery step (P1) of recovering from a machine tool a filter that removes machining debris generated by machining an object to be machined by the machine tool, and a storage step (P2) of storing the filter in a container having an inlet and an outlet for the liquid.

[0058] This allows the metal ion concentration in the liquid to be reduced without using an ion exchange resin or an insolubilizing agent, and also allows the filtration filter to be recycled.

[0059] The present invention is not limited to the above disclosure, and various configurations can be adopted without departing from the gist of the present invention.

[0060] REFERENCE SIGNS LIST 10: Regulating device 12: Container 14: Porous filter 16: Container body 18: Liquid inlet section 20: Liquid outlet section 22: Bypass pipe 24: Switch 26: Resistivity meter 28: Controller

Claims

1. An adjustment device for adjusting the resistivity of a liquid that does not contain solid metal objects and contains metal ions, comprising: a container having a liquid inlet and a liquid outlet; a porous filter accommodated in the container and configured to supply the liquid from the liquid inlet to the liquid outlet through pores; Equipped with Solid metal particles are trapped in the pores; The porous filter adjusts the resistivity of the liquid after it has passed through the pores to be greater than the resistivity of the liquid before it has passed through the pores.

2. The adjustment device according to claim 1 , The metal particles include at least one of iron, aluminum, copper, zinc, carbide, tungsten, molybdenum, carbon, titanium, silicon, manganese, chromium, phosphorus, sulfur, and nickel.

3. 3. The adjustment device according to claim 1 or 2, An adjustment device, wherein the metal particles are chips generated by machining an object to be machined using a machine tool.

4. 3. The adjustment device according to claim 1 or 2, An adjustment device, wherein the porous filter is a filter that has been used in the past as a filtration filter for removing machining debris generated by machining an object to be machined by a machine tool.

5. 3. The adjustment device according to claim 1 or 2, a bypass pipe that bypasses the porous filter and is connected to the liquid inlet and the liquid outlet; a switch that switches the supply destination of the liquid to either the bypass pipe or the porous filter; a resistivity meter that measures a resistivity value of the liquid supplied to the liquid inlet portion; a controller that controls the switch so that the supply destination of the liquid is switched to the porous filter when the resistivity value of the liquid is below a predetermined threshold, and controls the switch so that the supply destination of the liquid is switched to the bypass pipeline when the resistivity value of the liquid is equal to or greater than a predetermined threshold; An adjustment device comprising:

6. A method for adjusting the resistivity of a liquid that does not contain solid metal objects and contains metal ions, comprising the steps of: An adjustment method in which the liquid is passed through the pores of a porous filter in which solid metal particles are captured, thereby making the resistivity of the liquid after passing through the pores greater than the resistivity of the liquid before passing through the pores.

7. The adjustment method according to claim 6, a measuring step of measuring a resistivity value of the liquid supplied to the porous filter, and a switching step of switching a supply destination of the liquid to either a bypass line that bypasses the porous filter or the porous filter based on a measurement result, In the switching step, An adjustment method in which, when the resistivity value of the liquid falls below a predetermined threshold, the supply destination of the liquid is switched to the porous filter, and, when the resistivity value of the liquid is equal to or greater than a predetermined threshold, the supply destination of the liquid is switched to the bypass pipeline.

8. A method for manufacturing an adjusting device for adjusting the resistivity of a liquid that does not contain solid metal objects and contains metal ions, comprising the steps of: A recovery process of recovering, from the machine tool, a filtration filter that removes machining debris generated by machining an object to be machined by the machine tool; A step of housing the filtration filter in a container having an inlet and an outlet for the liquid; A manufacturing method comprising: