Machining position correction device and electrochemical machining device

Abstract

A machining position correction device (13) applied to an electrochemical machining apparatus, which causes an electrolyte (W) to flow from a distal end portion of an electrode rod (2) extending along an axis while the electrode rod (2) is rotated about the axis to electrochemically machine a material to be machined (100) in a region of the distal end portion of the electrode rod (2), the machining position correction device (13) comprising: a position detector (13A) configured to detect a rotational position of a characteristic point provided on the electrode rod (2), the rotational position representing a position of the characteristic point in a rotational direction of the electrode rod (2).

Description

Area

[0001] The present invention relates to a machining position correcting device used for an electrochemical machining apparatus which dissolves and machines a material to be machined by applying electricity to an electrode and the material to be machined via an electrolyte, and to the electrochemical machining apparatus. background

[0002] For example, a turbine blade of a gas turbine has a cooling hole for flowing a cooling medium, which cools the turbine guide vane and rotor blade formed therein. To increase the cooling efficiency by the cooling hole, the shape of the cooling hole is preferably curved along a geometric shape of a turbine blade.

[0003] Conventionally, for example, an electrochemical machining tool disclosed in Patent Literature 1 is intended to easily create a curved hole with a desired curvature. This electrochemical machining tool includes an electrode having a tubular shape, extending along an axis, and formed of a conductive material having flexibility, through which an electrolyte flows to a distal end side, an insulating layer covering an outer peripheral surface of the electrode to expose a distal end surface of the electrode, and a fluid discharge part at a portion of a location of the electrode in the circumferential direction, which is configured to discharge the electrolyte flowing through the inside of the electrode to the outside of a tool body in the radial direction.With this electrochemical machining tool, electricity is applied to a space between the distal end surface of the electrode and the inside of a machined hole of a material to be machined through an electrolyte to dissolve the material to be machined, allowing the machined hole to be machined / formed deeper. An electrolyte flowing through the inside of an electrode is discharged from the distal end of the electrode, and a portion of the electrolyte is also discharged from the fluid discharge part to the outside of a tool body in a radial direction. In this case, an electrolyte discharged from the fluid discharge part exerts a fluid action force on an inner surface of the machined hole to exert a reaction force of the fluid action force on the tool body.In this way, a tool body is displaced, allowing the tool body to bend in the direction of a reaction force, and a current density distribution of the distal end surface of an electrode and the inner surface of a machined hole is locally broadened depending on the displacement amount. Therefore, at a location of a tool body in the circumferential direction, the machining amount on a side where the tool body is displaced by a reaction force becomes large, and a machined hole is curved.

[0004] For example, a control device disclosed in Patent Literature 2 typically aims to provide a control device for an electrolytic machining apparatus capable of machining a curved hole to a target channel with high accuracy and high repeatability. In the electrolytic machining apparatus that causes electrolyte to flow from a distal end of an electrode rod and electrolytically machines a region from the distal end of the electrode rod while rotating an electrode rod having anisotropy at its distal end about an axis, this control device includes a distal-end dimensional information acquisition part for acquiring dimensional information of the distal end, which is position information related to the distal end of the electrode rod, a passage information storage part for storing a plane curve,selected based on preselected target channel information, a flow volume calculation part for calculating a flow volume of the electrolyte based on a deviation in a curve normal line direction of a plane curve obtained from a machining target position on the plane curve and the dimensional information of the distal end, and an electrode direction calculation part for determining a direction of the electrode rod about the axis based on the flow volume calculation part and a deviation in the normal line direction of a plane comprising a plane curve obtained from the machining target position on the plane curve and the dimensional information of the distal end.

[0005] Patent Literature 3 discloses that an electrochemical device applies penetrative processing to a workpiece by causing an electrolyte to flow out from a distal end of an electrode rod forming a tubular shape extending along an axial line, and applying a DC voltage between a distal end of the electrode rod and an inner wall surface of the workpiece while feeding the electrode rod to the distal end side. The electrode rod has an electric field uneven distribution structure, forming an electric field uneven distribution region where the electric field intensity is unevenly distributed over a circumferential portion at the distal end when the DC voltage is applied.The electrochemical device comprises a rotation drive device for rotating the electrode rod so that a rotation speed of the electrode rod is changed in accordance with a rotation phase angle about the axial line of the electrode rod.

[0006] Patent Literature 4 discloses that an electric discharge machine is provided with a measuring device for the vicinity of a measuring point for measuring a position in the vicinity of the position measuring point for a tool or a workpiece, a tool control device that generates the measurement history of a tool based on the result of the above measurements to control its relative position to measure the position of the tool by a tool measuring device, and / or a workpiece control device that generates the measurement history of the workpiece based on the result of the measurements performed by the devices to control the relative position of the workpiece to measure the position of the workpiece by a workpiece measuring device.

[0007] Patent Literature 5 discloses that an electrical discharge machining apparatus has a driving capability with improved responsiveness and machining speed. The tip of a tool electrode is directed toward a workpiece, and a voltage is applied between the tool electrode and the workpiece to generate a discharge. A drive shaft is connected to the tool electrode. An electrode drive device has magnetic bearings for moving the drive shaft in three directions: a Z-axis direction, which is an axial direction of the drive shaft, a Y-axis direction perpendicularly crossing the Z-axis direction, and an X-axis direction perpendicularly crossing the Y-axis and Z-axis directions, by supplying electric current to electromagnetic portions to control their magnetic attraction force.A movable coupling is connected to one end of the drive shaft and is movable in three directions. An electric motor is connected to one end of the coupling to rotate the drive shaft through the coupling. Citation listPatent literature Patent literature 1: JP 2013- 136 140 A Patent literature 2: JP 2016- 137 527 A Patent literature 3: JP 2013- 180 389 A Patent literature 4: JP H05-77 112 A Patent literature 5: DE 10 2004 005 118 A1 Summary Technical problem

[0008] The electrochemical machining tool disclosed in Patent Literature 1 can form a curved hole with a desired curvature. However, when the attachment phase of an electrode on a machining head (the position of the fluid discharge part in a rotational direction relative to the axis) is displaced, a displacement occurs in a machined direction and causes machining errors. For example, when the length of a material to be machined is equal to or greater than 800 mm and the length of an electrode used to machine this material to form a hole is equal to or greater than 1,000 mm, it is difficult to determine a phase angle at the time of attaching the electrode to a machining head.Because an electrode has flexibility, the phases at a base end and a distal end located at a machining head side can be shifted.

[0009] The control device disclosed in Patent Literature 2 can machine a curved hole with high accuracy and high repeatability to a target channel. However, if the amount of phase change from a machining initial state before a machining position is measured and controlled is large, machining errors of the entire machining channel become large.

[0010] The present invention has been made to solve the problems described above, and an object of the present invention is to provide a machining position correcting device capable of reducing an amount of phase change from a machining initial stage and reducing machining errors of the entire machining path, and an electrochemical machining device. Solution to the problem

[0011] The present invention provides a machining position correction device according to independent claim 1 and an electrochemical machining device according to independent claim 6. Advantageous modifications can be found in dependent claims 2 to 5. Advantageous effects of the invention

[0012] According to the present invention, a zero point correction can be performed using a position detector that detects characteristic points provided on an electrode, so that a detected rotational position is defined as an origin and used as a reference for an electrode phase (rotational position) of an electrode rod. After the zero point correction, the electrode phase is adjusted to a machining target phase, thereby reducing an amount of phase change from a machining initial stage and reducing machining errors along the entire machining path. Therefore, correcting an electrode phase of an electrode rod makes it possible to reduce machining errors, particularly in long-curved hole machining, and leads to improvements in machining accuracy, machining productivity, and a degree of design freedom. Short description of the drawings Fig. 1 is a schematic diagram showing an electrochemical machining apparatus in accordance with an embodiment of the present invention. Fig. 2 is a schematic diagram showing an electrochemical machining apparatus in accordance with the embodiment of the present invention. Fig. 3 is a schematic diagram showing an electrode rod in the electrochemical machining apparatus according to the embodiment of the present invention. Fig. 4 is a schematic diagram showing a machining position correcting device according to the embodiment of the present invention. Fig. 5 is an enlarged schematic diagram showing a machining position correcting device according to the embodiment of the present invention. Fig. 6 is a view showing a detection example of the machining position correcting device according to the embodiment of the present invention. Fig. 7 is an operation step view of the machining position correcting device according to the embodiment of the present invention. Fig. 8 is an explanatory view showing machining errors. Fig. 9 is a view showing another example of a characteristic point of the machining position correcting device according to the embodiment of the present invention. Fig. 10 is a view showing another example of a characteristic point of the machining position correcting device according to the embodiment of the present invention. Fig. 11 is a schematic diagram showing another example of the machining position correcting device according to the embodiment of the present invention. Description of the embodiments

[0013] An embodiment according to the present invention will now be described with reference to the accompanying drawings. It should be noted that the embodiments are not intended to limit this invention. Components in the embodiment include components that can be simplified or replaced with substantially similar components by those skilled in the art.

[0014] Fig. 1 is a schematic diagram showing an electrochemical machining apparatus according to the present embodiment. Fig. 2 is a schematic diagram showing an electrochemical machining apparatus according to the present embodiment. Fig. 3 is a schematic diagram showing an electrode rod in the electrochemical machining apparatus according to the embodiment of the present invention.

[0015] As shown in Fig. 1, the electrochemical machining apparatus in the present embodiment machines a cooling hole (hereinafter referred to as a hole) 100A in a material to be machined (workpiece) (e.g., a turbine blade of a gas turbine) 100 by electrochemical machining. The electrochemical machining apparatus includes a machining head 1, an electrode rod 2, a rotating mechanism 3, a lifting and lowering mechanism 4, a fixed base 5, a guide member 6, an electrolyte supply unit 7, a machining tank / container 8, a power source 9, a controller 10, a storage unit 11, an input / output unit 12, and a machining position correction device 13.

[0016] As shown in Fig. 1 and Fig. 2, the machining head 1 comprises a gripping unit 1A which grips a base end part of the electrode rod 2. A plurality of the gripping units 1A (four gripping units 1A in Fig. 2) are provided corresponding to a plurality of holes 100A to be made in the material 100 to be machined.

[0017] As shown in Fig. 3, the electrode rod 2 comprises an electrode 2A, an electrical insulating layer 2B, a radial direction outlet channel 2C and an axial direction outlet channel 2D.

[0018] The electrode 2A extends along the axis C and is formed in a tubular shape. The electrode 2A is a cylindrical body whose outer diameter is, for example, equal to or greater than 1 mm and equal to or less than 10 mm.

[0019] The electrode 2A is made of materials such as stainless steel, copper, and titanium to provide conductivity and flexibility. A flow path 2Aa through which an electrolyte flows is formed in the electrode 2A of a cylindrical body. The power source 9 can be connected to a base end portion of the electrode 2A, and the electrolyte supply unit 7 can be connected to the flow path 2Aa.

[0020] The electrically insulating layer 2B covers an outer peripheral surface 2Ab of the electrode 2A. The electrically insulating layer 2B is formed, for example, from a polyester resin having electrical insulation. The electrically insulating layer 2B does not cover a distal end surface 2Ac and a distal end side surface 2Ad of the electrode 2A, and the distal end surface 2Ac and the distal end side surface 2Ad are exposed. In the distal end side surface 2Ad, the number, size, location in an extending direction of the axis C of the electrode 2A, and the shape are not particularly limited.

[0021] The radial direction exhaust channel 2C is provided through an opening on a side opposite to the distal end side surface 2Ad (symmetrical position with respect to the axis C) above the axis C, and communicates the flow path 2Aa with the outside by passing through the electrode 2A and the electrically insulating layer 2B in the radial direction. The radial direction is a direction perpendicular to the axis C. An opening shape of the radial direction exhaust channel 2C is not particularly limited and may be rectangular or circular. When the radial direction exhaust channel 2C is inclined toward the inside, opposite to the distal end side surface 2Ad, the number of radial direction exhaust channels 2C is not limited to 1, and the size of the radial direction exhaust channel 2C is not particularly limited.

[0022] The axial direction outlet channel 2D is supplied through an opening of a tubular shape at the distal end of the electrode 2A along the axis C and connects the flow path 2Aa to the outside in communication.

[0023] The rotation mechanism 3 causes the gripping unit 1A to rotate about the axis C in the machining head 1. A motor, not shown, causes the gripping unit 1A to rotate and causes the electrode rod 2 gripped by the gripping unit 1A to rotate about the axis C in accordance with the rotation of the gripping unit 1A. The rotation mechanism 3 includes a rotation detector 3A that detects a rotation angle of the gripping unit 1A (electrode rod 2).

[0024] The raising and lowering mechanism 4 raises and lowers the machining head 1 along the axis C. A motor, not shown, raises and lowers the machining head 1 and raises and lowers the electrode rod 2 held by the gripping unit 1A along the axis C in accordance with the raising and lowering of the machining head 1. The raising and lowering mechanism 4 includes a position detector 4A that detects a raising and lowering position of the machining head 1 (electrode rod 2).

[0025] The fixed base 5 fixes the material to be machined 100 and the guide member 6. The fixed base 5 includes a fixing unit 5A, a first support unit 5B, and a second support unit 5C. The fixing unit 5A is fixed to a stationary jig base 15. The first support unit 5B supports the material to be machined 100, is movable in an axis extending direction and an axis rotating direction with respect to a vertical axis and first and second horizontal axes perpendicular to each other, and adjusts a vertical position and a horizontal position of the material to be machined 100.The second support unit 5C supports the guide member 6, is movable in an axis extension direction and an axis rotation direction with respect to the vertical axis and first and second horizontal axes perpendicular to each other, and adjusts a vertical position and a horizontal position of the guide member 6. In this way, the fixed base 5 adjusts the vertical positions and the horizontal positions of the material 100 to be machined and the guide member 6 together.

[0026] The guide member 6 is supported by the fixed base 5 and is arranged directly on a material 100 to be machined. The guide member 6 is provided with a guide hole 6A for communication of the machining head 1 side with the material 100 to be machined in an up / down direction. The guide hole 6A rotatably supports the electrode rod 2 around the axis C, while allowing the electrode rod 2 to be inserted therein in an up / down direction and a plurality of guide holes 6A (four guide holes 6A in Fig. 2) are provided corresponding to the holes 100A formed in the material 100 to be machined. The guide holes 6A are formed in accordance with the position of the holes 100A formed in the material 100 to be machined and an angle (direction) at which the distal end portion of the electrode rod 2 is inserted to form the holes 100A in the material 100 to be machined.Therefore, while the raising and lowering mechanism 4 lowers the electrode rod 2 inserted into the guide holes 6A, the distal end part of the electrode rod 2 is guided to reach the material 100 to be machined to match the position of the holes 100A made in the material 100 to be machined, and the distal end part of the electrode rod 2 is guided to reach the material 100 to be machined to match the angle of the machined holes 100A.

[0027] The electrolyte supply unit 7 supplies an electrolyte to the flow path 2Aa of the electrode 2A in the electrode rod 2. In the electrolyte supply unit 7, a supply line and a pump are connected to a storage part, which stores an electrolyte therein, and the supply line is connected to the flow path 2Aa of the electrode 2A through the machining head 1, which is not shown. Examples of the electrolyte include nitric acid and sodium nitrate.

[0028] The machining tank / container 8 covers the surroundings of the machining head 1 to which the electrode rod 2 is attached and the surroundings of the fixed base 5. In this way, the machining tank / container 8 prevents the dispersion of an electrolyte when protecting the material 100 to be machined during machining.

[0029] The energy source 9 supplies electrical energy to the electrochemical machining device.

[0030] The controller 10 is, for example, a computer and includes a microprocessor such as a central processing unit (CPU). The controller 10 includes a display device including a keyboard and a mouse, a sound output device including a speaker, and a drive device that stores data such as a computer program for performing arithmetic processing. The controller 10 reads from a recording medium in which the data is stored, which is not shown. Examples of the recording medium can be various types of recording media, for example, a recording medium that records optical, electrical, or magnetic information, such as a compact disc read-only memory (CD-ROM), a flexible disk, and a magneto-optical disk, and a semiconductor memory that electrically stores information, such as a read-only memory (ROM) and a flash memory.

[0031] The storage unit 11 is included in the controller 10 and includes memories such as a ROM and a random access memory (RAM) and a memory, and stores therein a computer program for executing arithmetic operations in the controller 10.

[0032] The input / output unit 12 inputs and outputs various types of data. Specifically, the input / output unit 12 is connected to the machining position correction device 13 and the controller 10, and outputs data input from the machining position correction device 13 to the controller 10.

[0033] The machining position correcting device 13, which will be described in detail later, detects a rotational position of the distal end part of the electrode rod 2 based on the characteristic points provided on the electrode rod 2. The detected data is output to the controller 10 through the input / output unit 12 as described above.

[0034] The controller 10 controls the electrochemical machining device (the rotating mechanism 3, the raising and lowering mechanism 4, the electrolyte supply unit 7, and the power source 9) based on data from the input / output unit 12 (machining position correcting device 13) and a computer program in the storage unit 11.

[0035] Specifically, the controller 10 causes the storage unit 11 to store a rotational position of the distal end portion of the electrode rod 2 obtained from the machining position correction device 13. Based on a computer program in the storage unit 11, the controller 10 causes the distal end portion of the electrode rod 2 to reach the material to be machined 100 through the raising and lowering mechanism 4. The controller 10 causes the power source 9 to supply electric power to the electrode 2A in the electrode rod 2 and causes the electrolyte supply unit 7 to supply an electrolyte to the flow path 2Aa of the electrode 2A. In this way, electricity is applied to a space between the distal end portion of the electrode 2A and the material to be machined through the electrolyte to dissolve the material to be machined 100 and introduce the holes 100A.During the curving and machining of the holes 100A, the controller 10 causes the rotating mechanism 3 to rotate the electrode rod 2. As shown in FIG. Fig. 3, an electrolyte W flowing through the flow path 2Aa of the electrode 2A is discharged from the axial direction discharge channel 2D on the distal end surface of the electrode 2A, and a part of the electrolyte W is also discharged from the radial direction discharge channel 2C to the outside of the electrode rod 2 in the radial direction. In this case, the electrolyte W discharged from the radial direction discharge channel 2C applies a fluid action force F1 to an inner surface of the holes 100A to exert a reaction force F2 of the fluid action force F1 on the distal end part of the electrode rod 2. In this way, the distal end part of the electrode rod 2 is displaced so that the distal end part bends in a direction where the reaction force F2 is directed toward M, and a current density distribution of the distal end surface of the electrode rod 2 and the inner surface of the holes 100A locally becomes wider depending on a displacement amount.Therefore, at a position of the electrode rod 2 in the circumferential direction, an amount of machining on a side where the electrode rod 2 is displaced by the reaction force F2 becomes large, and the holes 100A are curved.

[0036] Fig. 4 is a schematic diagram showing a machining position correcting device according to the embodiment of the present invention. Fig. 5 is an enlarged schematic diagram showing a machining position correcting device according to the embodiment of the present invention. Fig. 6 is a view showing a detection example of the machining position correcting device according to the embodiment of the present invention. Fig. 7 is an operation step view of the machining position correcting device according to the embodiment of the present invention. Fig. 8 is an explanatory view showing machining errors. Fig. 9 and Fig. 10 are views showing another example of a characteristic point of the machining position correcting device according to the embodiment of the present invention. Fig. 11 is a schematic diagram showing another example of the machining position correcting device according to the embodiment of the present invention.

[0037] As shown in Fig. 4 and Fig. 5, the machining position correction device 13 includes a position detector 13A. The position detector 13A detects a characteristic point provided on the electrode rod 2 and detects a rotational position of the distal end portion of the electrode rod 2 based on this characteristic point. Examples of characteristic points include the radial direction exhaust channel 2C formed in the electrode rod 2 and the distal end side surface 2Ad of the electrode 2A in the present embodiment. To detect the radial direction exhaust channel 2C and the distal end side surface 2Ad of the electrode 2A, examples of the position detector 13A include a proximity sensor (photoelectric, magnetic, eddy current, contact, laser detection, and the like) and an image sensor (image device).Furthermore, examples of detecting the distal end side surface 2Ad of the electrode 2A of the position detector 13A include an electrical conductivity sensor that detects a metal unit and an image sensor (image device). The position detector 13A is arranged on the guide member 6 and detects a characteristic point of the electrode rod 2 inserted into the guide hole 6A.

[0038] The machining position correcting device 13 detects, in a state where the rotating mechanism 3 rotates the electrode rod 2 inserted into the guide hole 6A, a characteristic point of the electrode rod 2 to detect a rotational position using the characteristic points as a reference. Fig. Figure 6 shows an example of data where a photoelectric proximity sensor that turns a detected signal on and off depending on a distance from a detected point to an object to be detected is used. In the case of the photoelectric proximity sensor, as indicated by a solid line in Fig. 6, the photoelectric proximity sensor detects the radial direction exhaust port 2C and the distal end side surface 2Ad, but the radial direction exhaust port 2C has a greater sensor detection strength. Therefore, a detection threshold is provided with respect to the signal detection strength to switch on and off a detected signal from only the radial direction exhaust port 2C, as indicated by the dot-dash line. In this way, a center position of the

[0039] Radial direction outlet channel 2C in a rotation direction can be calculated, and the center position of the radial direction outlet channel 2C in the rotation direction can be defined as an origin and used as a reference of an electrode phase (rotational position) of the distal end part of the electrode rod 2.

[0040] As in Fig. As shown in Figure 7, the controller 10 performs machining position correction processing. After an operator attaches the electrode rod 2 to the machining head 1 (step S1), the controller 10 controls the raising and lowering mechanism 4 to insert the electrode rod 2 into the guide holes 6A in the guide member 6 (step S2). At this time, the controller 10 obtains a raising and lowering position of the raising and lowering mechanism 4 and adjusts the distal end portion of the electrode 2A to a height of the position detector 13A (step S3). Thereafter, the controller 10 controls the rotating mechanism 3 to rotate the electrode rod 2 around the axis C, causes the position detector 13A to input a detected signal once for each rotation, and calculates the center position of the radial direction exhaust port 2C N times (step S4). N times indicates multiple times.If a deviation of a calculation result of the center position is N times equal to or less than X (Yes at step S5), the controller 10 performs a zero point correction (step S6) so that the center position is defined as an origin and used as a reference for an electrode phase (rotational position) of the electrode rod 2. The controller 10 causes the storage unit 11 to store therein the reference of the corrected electrode phase (rotational position) of the electrode rod 2. Thereafter, the controller 10 successfully completes this operation (step S7). In the subsequent machining operation, the controller 10 causes the rotation mechanism 3 to rotate the electrode rod 2 based on the reference of the correct electrode phase (rotational position) of the electrode rod 2.In contrast, in step S5, if a deviation of a calculation result of the center position is not equal to or less than X N times (No in step S5), the controller 10 determines whether a determination of No has occurred the Y-th time (for example, the third time) (step S8). If not (No in step S8), the processing returns to the processing in step S4, and the center position of the radial direction exhaust port 2C is calculated N times. If the determination of "No" occurs the Y-th time (Yes in step S8), the number of times a deviation of the calculation result of the center position exceeds X is equal to or greater than Y times (step S9), and this operation constitutes an abnormal end (step S10).Thereafter, if an inspection of the reason because a deviation exceeds X reveals, for example, the connection of the electrode rod 2 to the machining head 1 is insufficient, the operator reconnects the electrode rod 2 to the machining head 1 and performs the operation / machining again.

[0041] According to the machining position correction device 13 and the electrochemical machining device of the present embodiment, with the position detector 13A detecting a characteristic point provided on the electrode rod 2, zero point correction can be performed so that a detected rotational position is defined as an origin and used as a reference for an electrode phase (rotational position) of the electrode rod 2. After the zero point correction, the electrode phase is adjusted to a machining target phase to reduce the amount of phase change from a machining initial stage and reduce machining errors of the entire machining path.Therefore, correcting an electrode phase of the electrode rod 2 reduces machining errors, especially in the manufacturing of long curved holes, and leads to an improvement in machining accuracy, machine yield, and degree of freedom in design.

[0042] The following describes machining errors. Fig. 8 is an exemplary view showing machining errors. Fig. 8(a) shows a case where a zero point correction of the electrode phase (rotational position) of the electrode rod 2 is made. Fig. 8(b) shows a case where zero point correction of the electrode phase (rotational position) of the electrode rod 2 is not made.

[0043] As shown in Fig. 8(b), when zero-point correction of the electrode phase (rotational position) of the electrode rod 2 is not made, compared to a target route R1 of the design of the electrode rod 2 that makes the holes 100A in the material 100 to be machined, an amount of phase change of a machining route R2 reaching a machining start stage R2b from a machining start stage R2a is large. Even if the machining route R2 is corrected to the target route R1 from the machining start stage R2b, the machining route R2 cannot be promptly corrected to the target route R1 to smoothly connect the holes 100A. Therefore, the maximum machining errors between the target route R1 and the machining route R2 are large, and an overshoot is large until the machining route R2 is corrected to the target route R1.

[0044] In contrast, in the machining position correcting device 13 and the electrochemical machining device of the present embodiment, as shown in Fig. 8(a), by performing zero-point correction of the electrode phase (rotational position) of the electrode rod 2, compared with the target route R1, the configuration of the electrode rod 2 that forms the holes 100A in the material 100 to be machined, the amount of phase change of the machining route R2 reaching the machining start stage R2b from the machining start stage R2a is small. When the machining route R2 needs to be corrected from the machining start stage R2b to the target route R1, the machining route R2 can be immediately corrected to the target route R1. Therefore, the maximum machining error between the target route R1 and the machining route R2 is small, and the overshoot is also small until the machining route R2 is corrected to the target route R1.

[0045] It is preferable that the machining position correcting device 13 and the electrochemical machining device of the present embodiment include a support unit (guide member 6) which is arranged / positioned and fixed along and together with the material to be machined 100 and which supports and supports the electrode rod 2 rotatably inserted around the axis 10, and the position detector 13A is attached to the support unit (guide member 6).

[0046] In other words, by disposing the position detector 13A on the support unit (guide member 6) positioned and fixed along and together with the material to be machined 100, a support position of the electrode rod 2 can be positioned with respect to the material to be machined 100, and a zero point correction of the electrode phase (rotational position) of the electrode rod 2 can be made in this embodiment. Therefore, machining errors can be further reduced.

[0047] In the machining position correcting device 13 and the electrochemical machining device of the present embodiment, the support unit is preferably the guide member 6 that guides the electrode rod 2 to the material 100 to be machined.

[0048] In other words, the configuration for positioning a support position of the electrode rod 2 with respect to the machining material 100 to be machined can be shared with the guide member 6 that guides the electrode rod 2 toward the machining material 100, and the number of components can be reduced and the device can be downsized.

[0049] In the machining position correcting device 13 and the electrochemical machining device of the present embodiment, the position detector 13A preferably detects the radial direction exhaust port 2C or the distal end side surface 2Ad as a characteristic point.

[0050] In other words, a new characteristic point is not necessarily provided by detecting the configuration of machining the curved holes 100A into the material 100 to be machined as a characteristic point. Therefore, the number of configurations for performing zero point correction of the electrode phase (rotational position) of the electrode rod 2 can be reduced.

[0051] The characteristic point is not limited to the radial direction outlet channel 2C and the distal end side surface 2A described above. Fig. 9 and Fig. 10 are views showing another example of the characteristic point of the machining position correcting device according to the present embodiment.

[0052] The characteristic point shown in Fig. 9, is a straight line 2E gradually drawn along the axis C on the surface of the electrode rod 2. The straight line 2E is, for example, drawn on a line where the center of the distal end side surface 2Ad extends along the axis C. Detection of the straight line 2E by the position detector 13A makes it possible to detect a rotational position of the distal end side surface 2Ad. In addition, because the straight line 2E is gradually drawn along the axis C, the straight line 2E can be detected in real time during machining.

[0053] The characteristic point shown in Fig. 10, is a curved line 2F drawn by sequentially rotating the electrode rod 2 with respect to the extending direction of the axis C to match a rotational position of the electrode rod 2 corresponding to the curvature of the holes 100A formed on the surface of the electrode rod 2. By rotating the descending electrode rod 2 such that the position detector 13A detects the curved line 2F, the holes 100A can be formed with a predetermined curvature. Furthermore, the curved line 2F can be detected in real time during machining because the curved line 2F is sequentially drawn along the axis C.

[0054] Fig. 11 is a schematic diagram showing another example of the machining position correcting device according to the present embodiment.

[0055] The machining position correction device 13 shown in Fig.11 includes a support unit 13B formed independently of the guide member 6. The support unit 13B is provided with support holes 13Ba that support the electrode rods 2 rotatably around the axis C while allowing the electrode rods 2 to be inserted therein in an up-and-down direction. The support unit 13B is provided with the position detector 13A to match the position of the support holes 13Ba. The support holes 13Ba and the position detector 13A are provided by the number of electrode rods 2 mounted on the electrochemical machining apparatus. This support unit 13B is attachably and detachably provided on the guide member 6 and is arranged / positioned and fixed by a positioning mechanism 13C.The positioning mechanism 13C determines vertical and horizontal positions of the support holes 13Ba of the support unit 13B with respect to the guide member 6. By fixing the support unit 13B to the guide member 6 with the positioning mechanism 13C, the support positions, vertical positions and horizontal positions of the electrode rods 2 are arranged / positioned with respect to the machining material 100 to be machined, and zero point correction of the electrode phase (rotational position) of the electrode rods 2 can be made in this embodiment.

[0056] In this way, the machining position correcting device 13 of the present embodiment includes the support unit 13B which is attachable and detachable and is arranged / positioned and fixedly provided on the guide member 6 which guides the electrode rod 2 to the material 100 to be machined.

[0057] For example, if a nitric acid-based electrolyte or a sodium nitrate-based electrolyte is used and acts on the position detector 13A, the service life of the position detector 13A may be shortened. In the machining position correcting device 13 of the present embodiment, the support unit 13B is provided attachably and detachably on the guide member 6, and the support unit 13B is removed from the guide member 6 during machining, thereby preventing an electrolyte from acting on the position detector 13A. List of reference symbols 1 machining head 1A gripping unit 2 electrode rods 2A electrode 2Aa flow path 2Ab Outer peripheral surface 2Ac Distal end surface 2Ad Distal end-side surface 2B Electrical insulation layer 2C Radial direction outlet channel 2D axial direction outlet channel 2E Straight Line 2F Curved line 3 rotating mechanism 3A Turning Investigator 4 Lifting and lowering mechanism 4A Position detector 5 Fixed base 5A mounting unit 5B First Support Unit 5C Second Support Unit 6 Guide element 6A Guide hole 7 Electrolyte supply unit 8 processing tank / container 9 Energy source 10 controllers 11 Storage unit 12 Input / output unit 13 Machining position correction device 13A Position detector 13B Support Unit 13Ba support hole 13C Positioning mechanism 15 Fixture base 100 material to be machined 100A hole C axis F1 Fluid action force F2 reaction force M Direction in which the reaction force points R1 destination route R2 Machining route W Electrolyte

Claims

[1] A machining position correction device (13) applied to an electrochemical machining apparatus which causes an electrolyte (W) to flow from a distal end portion of an electrode rod (2) extending along an axis while the electrode rod (2) is rotated about the axis to electrochemically machine a material to be machined (100) in a region of the distal end portion of the electrode rod (2), the machining position correction device (13) comprising: a position detector (13A) configured to detect a rotational position of a characteristic point provided on the electrode rod (2), the rotational position representing a position of the characteristic point in a rotational direction of the electrode rod (2). [2] The machining position correcting device (13) according to claim 1, further comprising: a support unit (13B) positioned and fixed together with the material (100) to be machined, the support unit (13B) allowing the electrode rod (2) to be inserted and supported therein so as to be rotatable about the axis, wherein the position detector (13A) is attached to the support unit (13B). [3] The machining position correcting device (13) according to claim 2, wherein the support unit (13B) is a guide member that guides the electrode rod (2) to the material to be machined (100). [4] The machining position correcting device (13) according to claim 2, wherein the support unit (13B) is provided attachably and detachably on, and positioned and fixed to, a guide member (6) which guides the electrode rod (2) to the material to be machined (100). [5] The machining position correcting device (13) according to any one of claims 1 to 4, wherein the electrode rod (2) has: an electrode (2A) extending along the axis and having a tubular shape, the electrode (2A) being made of a conductive flexible material, an insulating layer (2B) covering an outer peripheral surface (2Ab) of the electrode (2A) to expose a distal end surface (2Ac) of the electrode (2A), and a radial direction outlet channel (2C) provided at a part of the distal end portion of the electrode rod (2) at a position in a radial direction, the radial direction outlet channel (2C) being formed from inside the electrode rod (2) to the outside in the radial direction, and the position detector (13A) detects the radial direction exhaust port (2C) as the characteristic point. [6] An electrochemical machining apparatus which causes an electrolyte (W) to flow from a distal end portion of an electrode rod (2) extending along an axis while the electrode rod (2) is rotated about the axis to electrochemically machine a material to be machined (100) in a region of the distal end portion of the electrode rod (2), the electrochemical machining apparatus comprising: a machining head (1) which supports the electrode rod (2) rotatably about the axis; and a controller (10) configured to control a rotational position of the electrode rod (2) in the machining head (1), wherein the controller (10) controls the machining head (1) based on the rotational position obtained from the machining position correcting device (13) according to any one of claims 1 to 5.

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