EDM machine for engraving molds

Abstract

The engraving EDM machine (100) includes: a spindle (1); a machining electrode (5) which is detachably mounted on the spindle (1) and performs machining on the workpiece (16) by non-contact discharge to the workpiece (16) placed in an insulating machining fluid; an imaging device (3) which is detachably mounted on the spindle (1) and interchangeable with the machining electrode (5) to take pictures of the workpiece (16) after machining by the machining electrode (5) and obtain imaging data representing the shape of the workpiece (16) after machining; a contact detection unit (70) connected to the spindle (1) and detecting contact when the imaging device (3) and the workpiece (16) are in contact when the imaging device (3) is mounted on the spindle (1); and an NC device (72) that controls the movement and stopping of the spindle (1) and causes the movement of the spindle (1) to stop urgently when the contact detection unit (70) detects the contact. The user checks the shape and size of the workpiece (16) based on the captured data.

Description

Technical Field

[0001] This invention relates to an electrical discharge machining (EDM) machine for engraving molds. Background Technology

[0002] Generally speaking, a die-cutting electrical discharge machining (EDM) machine is a device that performs die-cutting electrical discharge machining to transfer the shape of a machining electrode onto a workpiece. In die-cutting EDM, the workpiece is first placed on a machining platform relative to a machining tank filled with an insulating machining fluid such as oil or water. Next, with the machining electrode and workpiece facing each other, the high-precision machining electrode is brought closer to the workpiece, and a current is discharged through the electrode. During this process, the workpiece is machined while maintaining a constant distance of approximately tens of micrometers between it and the machining electrode. This gap between the workpiece and the machining electrode is called the discharge gap. Through these steps, the workpiece is machined into a three-dimensional shape with the transferred shape of the machining electrode.

[0003] In EDM (Electrical Discharge Machining) for engraving, the workpiece is removed from the machine platform after machining to verify that its shape and dimensional accuracy meet requirements. If the verification result shows that the requirements are not met, additional machining is performed on the workpiece. In the case of additional machining, the workpiece is placed back on the machine platform, thus consuming time until the re-machining begins. Furthermore, if the workpiece is temporarily removed from the machine platform, accurately reproducing its previous state and repositioning it in the exact same location is extremely difficult. Additionally, even if the workpiece's position can be perfectly reproduced, changes in the positions of the machinery and tools may occur over time, making accurate correction impossible even after re-machining for dimensional adjustment.

[0004] Therefore, a method is required that allows for the confirmation of the shape and dimensions of the workpiece without removing it from the machining platform. For example, the method described in Patent Document 1 has been proposed. In Patent Document 1, a camera is mounted relative to the spindle on which the tool is mounted and arranged with the tool. The camera moves synchronously with the tool. The image obtained by the camera is automatically processed by a recognition device and then displayed on a monitor. The user can confirm the shape and dimensions of the workpiece based on the displayed image.

[0005] Patent Document 1: Japanese Patent Application Publication No. 4-93150 Summary of the Invention

[0006] The NC (Numerical Control) machine described in Patent Document 1 is a processing device that mainly performs grinding operations and does not intend to perform processing while the workpiece is immersed in the processing fluid.

[0007] On the other hand, in the EDM process of a die-cutting machine, oil fumes are generated from the processing fluid. Therefore, as described in Patent Document 1, if a camera is mounted on the spindle, the lens of the camera may be soiled by the oil fumes, or the internal substrate of the camera may be degraded and malfunction due to the oil fumes.

[0008] As described above, when the camera described in Patent Document 1 is applied to a die-cutting electrical discharge machining machine instead of a general work machine, the following problems exist: the camera lens will become dirty due to the oil fumes during die-cutting electrical discharge machining, making it impossible to take a clear image, and the internal substrate of the camera may malfunction.

[0009] The present invention was made in view of the above circumstances, and its object is to provide a die-cutting electrical discharge machining machine that can prevent dirt from getting on the lens of the imaging device and prevent malfunctions of the imaging device, and can confirm the shape and size of the workpiece without removing the workpiece from the platform.

[0010] To solve the aforementioned problems and achieve the objectives, the EDM (Electrical Discharge Machining) machine for engraving molds according to the present invention is characterized by comprising: a spindle; a machining electrode detachably mounted on the spindle, which performs non-contact discharge on a workpiece placed in an insulating machining fluid to process the workpiece; an imaging device detachably mounted on the spindle and interchangeable with the machining electrode, which takes pictures of the workpiece after processing by the machining electrode to obtain imaging data representing the shape of the processed workpiece; a contact detection unit connected to the spindle, which detects contact when the imaging device and the workpiece are in contact when the imaging device is mounted on the spindle; and a NC (Non-Conductive) device that controls the movement and stopping of the spindle, wherein the NC device causes an emergency stop of the spindle movement when the contact detection unit detects contact.

[0011] The effects of the invention

[0012] The engraving EDM machine of the present invention has the following effects: it can prevent dirt from getting on the lens of the imaging device and prevent the imaging device from malfunctioning, and it can confirm the shape and size of the workpiece without removing it from the platform. Attached Figure Description

[0013] Figure 1 This is a diagram showing the structure of the EDM machine involved in Embodiment 1.

[0014] Figure 2This is a diagram showing the internal structure of the control box installed in the EDM machine according to Embodiment 1.

[0015] Figure 3 This is a schematic diagram illustrating the method for photographing and confirming the workpiece in the EDM machine according to Embodiment 1.

[0016] Figure 4 This is a flowchart illustrating the processing flow of the NC device and control box installed in the engraving EDM machine according to Embodiment 1.

[0017] Figure 5 This is a diagram showing an example of the structure of the ATC installed in the EDM machine according to Embodiment 1.

[0018] Figure 6 This is a schematic diagram illustrating the situation where the imaging device and processing electrode are replaced by an ATC installed in the engraving EDM machine according to Embodiment 1.

[0019] Figure 7 This is a diagram showing an example of the connector connection structure provided in the EDM machine according to Embodiment 1.

[0020] Figure 8 This is a diagram showing the structure of the roller bearing in the second connector terminal of the engraving EDM machine according to Embodiment 1 to prevent it from falling off.

[0021] Figure 9 This is a diagram showing the structure of the contact detection function in the EDM machine according to Embodiment 1.

[0022] Figure 10 This is a diagram showing the structure of the insulation function in the EDM machine according to Embodiment 1.

[0023] Figure 11 This is a diagram illustrating an example of the structure of a processing circuit in which the processing circuit of the control box according to Embodiment 1 is implemented by a processor and a memory.

[0024] Figure 12 This diagram illustrates an example of a processing circuit in which the processing circuit of the control box described in Embodiment 1 is constructed using dedicated hardware.

[0025] Figure 13 This is a diagram showing the internal structure of the power board installed in the EDM machine according to Embodiment 1.

[0026] Figure 14 This is a diagram showing the internal structure of the numerical control device (NC device) installed in the EDM machine for engraving molds according to Embodiment 1.

[0027] Figure 15 This is a diagram showing the wiring structure when a machining electrode is mounted in the EDM machine according to Embodiment 1.

[0028] Figure 16 This is a diagram showing the wiring structure when a camera and a control box are installed in the EDM machine according to Embodiment 1. Detailed Implementation

[0029] The engraving EDM machine according to the embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0030] Implementation method 1.

[0031] (Structural elements)

[0032] Figure 1 This is a diagram showing the structure of the engraving EDM machine according to Embodiment 1. The engraving EDM machine 100 includes a spindle 1, an electrode chuck 2, an imaging device 3, a control box 4, a processing electrode 5, a contact detection circuit 7, an ATC (Automatic Tool Changer) 9, a power board 10, and a platform 21. The power board 10 has a contact detection unit 70.

[0033] like Figure 1 As shown, an electrode chuck 2 is provided on the spindle 1 of the engraving EDM machine 100. The electrode chuck 2 is a mounting component for mounting the imaging device 3 or the processing electrode 5 onto the spindle 1. The imaging device 3 or the processing electrode 5 can be detachably fixed to the spindle 1 via the electrode chuck 2. The imaging device 3 and the processing electrode 5 are not both mounted on the spindle 1 simultaneously; only one of them is always mounted on the spindle 1. Figure 1 In the example, the state in which the imaging device 3 is mounted on the electrode chuck 2 is shown.

[0034] The imaging device 3 has a lens 3a at its lower end. The lens 3a is positioned opposite the workpiece 16. The imaging device 3 is powered via a control box 4. The imaging device 3 and the control box 4 are connected via a power supply line 41 for supplying power and a signal line 45 for transmitting imaging data. After the workpiece 16 is processed by the EDM machine 100, the imaging device 3 takes a picture of the workpiece 16. Furthermore, the imaging device 3 transmits the imaging data obtained through this imaging to the control box 4 via the signal line 45. Power is supplied to the imaging device 3 from a power source 30 via the control box 4. The power source 30 is, for example, an external power source such as a socket. The power source 30 may be an AC power source such as a commercial power supply, but may also be a DC power source such as a battery. The imaging device 3 may be, for example, a camera.

[0035] Control box 4 is connected to power supply 30 via power cord 40. Control box 4 supplies power from power supply 30 to imaging device 3. Additionally, control box 4 performs image processing on the imaging data received from imaging device 3 to generate image data 15. Image data 15 is input to PC (Personal Computer) 8 via signal line 42. The user displays image data 15 on PC 8's screen and confirms the shape and size of workpiece 16 based on image data 15. As described above, image data 15 is sequentially forwarded from control box 4 to PC 8, allowing the user to use PC 8 to confirm the processing status of workpiece 16 in real time during imaging by imaging device 3. Furthermore, control box 4 is connected to ground 11 via ground wire 43.

[0036] Figure 2 This is a diagram showing the internal structure of the control box installed in the EDM machine according to Embodiment 1. (See diagram for example.) Figure 2 As shown, the control box 4 includes a power supply unit 4a, an image processing unit 4b, a storage unit 4c, and a calculation unit 4d. The power supply unit 4a uses power from the power source 30 to supply power to the imaging device 3. The image processing unit 4b processes the imaging data acquired by the imaging device 3 to generate image data 15. The storage unit 4c stores the operation program of the control box 4 and various data such as the calculation results of the control box 4. The calculation unit 4d performs various calculations to confirm the shape and size of the workpiece 16. Figure 2 This is one example of control box 4, but it is not limited to this. Control box 4 does not necessarily need to have... Figure 2 All of the parts shown, in addition, may also have Figure 2 Other structures besides the parts shown. And, Figure 2 Some or all of the components of the control box 4 can be comprised of a cloud server. Alternatively, the control box 4 can also be comprised of a server. In this case, the control box 4 can be located near the engraving EDM machine 100, or it can be remotely located. When the control box 4 is remotely located, the control box 4 and the engraving EDM machine 100 can be connected via a network such as the Internet. Furthermore, in Figure 1 In this example, the control box 4 and the power board 10 are constructed separately, but this is not limited to... Figure 1 For example, the control box 4 can be mounted inside the power board 10 or located outside the power board 10.

[0037] Return to Figure 1The machining electrode 5 is mounted on the spindle 1 via the electrode chuck 2. The machining electrode 5 is machined with high precision to a shape that reverses the final shape of the workpiece 16. The machining electrode 5 is made of materials such as copper or graphite, which are conductive. Alternatively, the machining electrode 5 may be made of other materials such as tungsten, which are conductive only at temperatures above a certain threshold. The machining electrode 5 processes the workpiece 16 by discharging a non-contact discharge relative to the workpiece 16, which is placed in an insulating processing fluid.

[0038] The EDM (Electrical Discharge Machining) process for engraving molds will be explained in more detail. First, the workpiece 16 is placed in a machining tank filled with machining fluid. Next, the machining electrode 5 is brought closer and closer to the workpiece 16, and a current is discharged through the machining electrode 5. As a result, the workpiece 16 is machined into a 3D shape after the shape of the machining electrode 5 is reversed. The shape of the workpiece 16 after machining is sometimes referred to as the product shape. Furthermore, by using an ATC (Automatic Transmission Control) 9, the machining electrode 5 and the imaging device 3 can be automatically changed relative to the spindle 1 without manual operation by the user, simply by running a program.

[0039] The machining fluid used in EDM (Electrical Discharge Machining) for engraving is composed of an insulating liquid such as water or oil. When the workpiece 16 and the machining electrode 5 are made insulated by the machining fluid, if the workpiece 16 and the machining electrode 5 come into close proximity, insulation breakdown will occur between them. Insulation breakdown refers to the phenomenon where, when the electric field applied to the insulator exceeds a threshold, the resistance drops sharply, resulting in the flow of a large current. Due to insulation breakdown, a pulse current instantaneously flows in, creating a high-density discharge state—an arc column—and the surface of the workpiece 16 locally reaches a high temperature, for example, around 6000–7000°C. As a result, the workpiece 16, which is made of metal, melts. By performing insulation breakdown and melting processes on each processing area of ​​the workpiece 16, processing continues until the workpiece 16 finally takes the product shape.

[0040] The imaging device 3 includes: a frame (not shown); an imaging device cover 6, which is mounted to cover the frame; a lens 3a; and an electrical unit 3b (see reference). Figure 9 The frame forms the outer contour of the imaging device 3. The electrical unit 3b contains an internal board that implements various functions of the imaging device 3. The imaging device cover 6 is conductive. The imaging device cover 6 is as follows... Figure 1 As shown, for example, it has a cylindrical shape. The lower end of the imaging device cover 6 is open. The lens 3a, which is provided at the lower end of the imaging device 3, protrudes outward from this opening of the imaging device cover 6. When the imaging device 3 is mounted on the spindle 1, the lens 3a and the workpiece 16 are in a state of facing each other. The imaging device cover 6 is connected to the contact detection circuit 7 of the engraving EDM machine 100.

[0041] The contact detection circuit 7 has a first contact detection line 7a and a second contact detection line 7b. The first contact detection line 7a connects the platform 21 (not shown) provided in the machining tank and the contact detection unit 70. The second contact detection line 7b connects the imaging device cover 6 and the contact detection unit 70. When the imaging device cover 6 and the workpiece 16 are in contact, an electrical circuit is formed via the contact detection circuit 7 through the imaging device cover 6, the workpiece 16, the platform 21, and the contact detection unit 70. The contact detection unit 70 detects contact between the imaging device cover 6 and the workpiece 16 based on the conduction state of this electrical circuit, that is, when it detects current flowing through the electrical circuit. When the contact detection unit 70 detects this contact, the spindle control unit 72a (see below) in the numerical control device (hereinafter referred to as NC device) 72 provided on the power supply board 10 is activated. Figure 14 This instantly stops the spindle 1. Therefore, damage to the imaging device 3 and the workpiece 16 can be minimized. Furthermore, the lower end of the imaging device cover 6 is preferably at the same height as the lens 3a of the imaging device 3, or extends to a position lower than the lens 3a. In addition, in the description of Embodiment 1, for the sake of simplicity, the "contact between the imaging device cover 6 of the imaging device 3 and the workpiece 16" is sometimes referred to as "the contact between the imaging device 3 and the workpiece 16".

[0042] The EDM machine 100 includes an ATC 9, which performs the replacement of the machining electrode 5 and the imaging device 3 relative to the spindle 1. The ATC 9 performs the replacement of the machining electrode 5 and the imaging device 3 relative to the spindle 1 in response to signals input from an external source. These external signals are, for example, commands from the ATC control unit 72b within the NC device 72 (described later) located on the power board 10. When the NC device 72 determines that the machining of the workpiece 16 is complete, it outputs a command to the ATC 9 to remove the machining electrode 5 from the spindle 1 and replace it with the imaging device 3. Furthermore, when the NC device 72 receives a command from the PC8 to perform re-machining of the workpiece 16, it outputs a command to the ATC 9 to remove the imaging device 3 from the spindle 1 and replace it with the machining electrode 5. Based on these commands from the NC device 72, the ATC 9 automatically mounts and removes the machining electrode 5 or the imaging device 3 relative to the spindle 1. The machining electrode 5 or the imaging device 3 removed from the spindle 1 is returned to the box 9a of the ATC 9. The ATC 9 is sometimes referred to as an automatic tool changer.

[0043] like Figure 1As shown, the imaging device 3 is provided with a first connector terminal 12 for connector connection. Additionally, the spindle 1 is provided with a second connector terminal 13 for connector connection. By connecting the first connector terminal 12 of the imaging device 3 to the second connector terminal 13 of the spindle 1, wired connections can be made between the imaging device 3 and the control box 4, as well as between the imaging device cover 6 and the contact detection unit 70. Furthermore, the body of the first connector terminal 12 may be mounted on the imaging device cover 6 instead of the imaging device 3. On the other hand, the first connector terminal 12 is not provided on the processing electrode 5.

[0044] In power board 10, such as Figure 1 As shown, a contact detection unit 70 is provided inside. Here, Figure 13 This is a diagram showing the internal structure of the power board installed in the engraving EDM machine according to Embodiment 1. If using... Figure 13 To explain in more detail, the power board 10 is provided with a contact detection unit 70, a power supply unit 71, and an NC device 72. The contact detection unit 70 detects the contact between the imaging device cover 6 and the workpiece 16, and also detects the contact between the machining electrode 5 and the workpiece 16. When the contact detection unit 70 detects any of these contacts, it outputs a contact detection signal to the NC device 72. If the NC device 72 receives the contact detection signal, it then processes the signal via the spindle control unit 72a (see below). Figure 14 This instantly stops the spindle 1. As a result, damage to the imaging device 3, the processing electrode 5, and the workpiece 16 can be minimized. Figure 13 The power supply unit 71 shown uses power from the power supply 30 to supply power to the ATC 9, the processing electrode 5, and the drive device 50. Figure 13 The NC device 72 shown controls the machining of the workpiece 16 by controlling the spindle 1, ATC 9 and machining electrode 5. Figure 14 This is a diagram showing the internal structure of the numerical control (NC) device installed in the EDM machine for engraving molds according to Embodiment 1. (See diagram below.) Figure 14 As shown, the NC device 72 includes a spindle control unit 72a, an ATC control unit 72b, and a machining control unit 72c. The spindle control unit 72a controls the movement and stopping of the spindle 1, and performs emergency stops for the spindle 1 in case of emergencies. The ATC control unit 72b controls the operation of the ATC 9, enabling the ATC 9 to change the machining electrode 5 and the imaging device 3. The machining control unit 72c outputs a power command to the power supply unit 71 within the power board 10, thereby supplying power to the machining electrode 5. Furthermore, the machining control unit 72c also controls the value of the machining voltage in the machining electrode 5. Figure 1 As shown, power board 10 is connected to power supply 30. Additionally, power board 10 is connected to ground 11 via ground wire 44.

[0045] return Figure 1 Description. Platform 21 is set in a machining tank (not shown). Platform 21 as... Figure 1 As shown, it has a flat plate shape. The shape of platform 21 can be rectangular or circular when viewed from above. The upper surface of platform 21 is, for example, set to be horizontal. Figure 1 As shown, a workpiece 16 is placed on the upper surface of platform 21. Platform 21 is connected to contact detection unit 70 via a first contact detection line 7a. Platform 21 is conductive. Platform 21 is sometimes referred to as a machining platform.

[0046] A PC 8 is connected to the EDM machine 100. The PC 8 can be an integral part of the EDM machine 100 or located externally. The PC 8 has a display device such as a monitor. Furthermore, the PC 8 has a user interface that receives various inputs through user operation. The user interface can be, for example, a keyboard or mouse. The PC 8 outputs instructions to the NC device 72 based on the input from the user.

[0047] (Shooting method of shooting device 3)

[0048] Figure 3 This is a schematic diagram illustrating the method for photographing and confirming the workpiece in the EDM machine according to Embodiment 1. Figure 3 The upper part shows the photographic data of the workpiece 16. Figure 3 The upper part of the shooting data captured the overall situation of the processed object 16. Figure 3 The lower left side of the diagram shows a partial image 60 of the workpiece 16 when the position of the spindle 1 coincides with the first measuring point A, which will be described later. The lower right side of the diagram shows a partial image 61 of the workpiece 16 when the position of the spindle 1 coincides with the second measuring point B, which will be described later. Images 60 and 61 are, for example, examples of images displayed on the screen of PC 8 based on image data 15.

[0049] First, the process of confirming the shape of the workpiece 16 will be explained. The imaging device 3 is capable of clearly capturing the fine shape of the surface of the workpiece 16 with sub-micron precision. The imaging data representing the shape of each part of the workpiece 16 acquired by the imaging device 3 is transmitted to the control box 4 in real time. The control box 4 performs image processing on the imaging data by the image processing unit 4b, thereby converting the imaging data into image data 15. The image data 15 is transmitted from the control box 4 to the PC 8. Thus, the user can sequentially confirm the shape and size of the workpiece 16 by displaying the image data 15 on the screen of the PC 8.

[0050] Furthermore, since the imaging device 3 is mounted on the main shaft 1, it can move along with the main shaft 1. Therefore, by moving the imaging device 3 in the height direction to increase the distance between the workpiece 16 and the imaging device 3, a wide range of imaging of the workpiece 16 can be performed. Conversely, by moving the imaging device 3 in the height direction to decrease the distance between the workpiece 16 and the imaging device 3, localized fine details of the workpiece 16 can be imaged. As described above, since the imaging device 3 can be moved, arbitrary imaging of both wide and narrow ranges of the workpiece 16 can be performed, and the focus adjustment area of ​​the imaging device 3 becomes extensive. Moreover, the imaging device 3 can also move along with the main shaft 1... Figure 1 The X-direction movement. Therefore, in the workpiece 16, the positions of the first measuring point A and the second measuring point B are predetermined, so that the spindle 1 moves sequentially to the first measuring point A and the second measuring point B, and local imaging data can also be obtained at the position of each measuring point.

[0051] Next, the dimensional measurement of the workpiece 16 will be described. As described above, the spindle 1 can move in the X direction, for example, via the drive unit 50. The X direction is, for example, the horizontal direction. The drive unit 50 is, for example, an electric motor. The operation of the drive unit 50 is controlled by the spindle control unit 72a of the NC device 72. Power is supplied to the drive unit 50 via power cord 46 using power from the power supply unit 71 within the power supply board 10. The power cord 46 is described later. Figure 15 and Figure 16 As shown, the drive unit 50 and the power supply unit 71 are connected through the spindle 1. The drive unit 50 is provided inside or outside the spindle 1. Here, the spindle 1 is described as moving in the vertical and horizontal directions by the drive unit 50, but the structure that moves the spindle 1 can also be other structures. For the following explanation, the left end edge of the workpiece 16 is referred to as the first edge 16a, and the right end edge of the workpiece 16 is referred to as the second edge 16b. In addition, a predetermined point on the first edge 16a is referred to as the first measuring point A, and a predetermined point on the second edge 16b is referred to as the second measuring point B.

[0052] First, the spindle control unit 72a of the NC device 72 moves the spindle 1 to align it with the first edge 16a or the first measuring point A of the workpiece 16. Furthermore, when the position of the imaging device 3 mounted on the spindle 1 matches the position of the first edge 16a or the first measuring point A, the control box 4 adjusts the current machine coordinates of the spindle 1, i.e., the position of the spindle 1, to... Figure 3 The coordinates (x) of the first measurement point A when they match a y aThe coordinates of the position of the main shaft 1 when they coincide with the first measurement point A are sometimes simply referred to as the coordinates of the first measurement point A or the first coordinates.

[0053] Next, the spindle control unit 72a of the NC device 72 moves the spindle 1 to align it with the second edge 16b or the second measuring point B of the workpiece 16. Furthermore, when the position of the imaging device 3 mounted on the spindle 1 matches the position of the second edge 16b or the second measuring point B, the control box 4 adjusts the current mechanical coordinates of the spindle 1, i.e., the position of the spindle 1, to align with... Figure 3 The coordinates (x) of the second measurement point B when they coincide b y b The coordinates of the position of the main shaft 1 when they coincide with the second measurement point B are sometimes simply referred to as the coordinates of the second measurement point B or the second coordinates.

[0054] The arithmetic unit 4d of the control box 4 is based on the coordinates (x, y, y) of the first measurement point A stored in the storage unit 4c. a y a ) and the coordinates (x) of the second measurement point B b y b The distance between the first edge 16a and the second edge 16b and the distance between the first measuring point A and the second measuring point B are calculated. These distances can be calculated, for example, by the following equation (1).

[0055] The distance between AB = {(x a -x b ) 2 +(y a -y b ) 2} 1 / 2 ··· (1)

[0056] As described above, the control box 4 can calculate the desired distance between two edges or the desired distance between two measurement points. Furthermore, the example described here is the calculation unit 4d of the control box 4 performing these distance calculations, but it is not limited to this case. These distances can also be calculated by the PC 8, for example.

[0057] Using PC 8, the user compares the shape and dimensions of each part of the workpiece 16 with the design data based on the distance between two edges or the distance between two measuring points. This confirms whether the workpiece 16 has been precisely processed into the final product shape, or whether the dimensional accuracy meets the preset conditions. Furthermore, if the confirmation result indicates that the workpiece 16 has not been precisely processed into the final product shape, the user replaces the imaging device 3 and the processing electrode 5, and performs the engraving EDM process on the workpiece 16 again.

[0058] Figure 4 This is a flowchart illustrating the processing flow of the NC device and control box installed in the engraving EDM machine according to Embodiment 1. Figure 4 The diagram illustrates the process of determining the distance between the first measuring point A and the second measuring point B within the processing of the NC device 72 and the control box 4. This process is repeated for each processing area of ​​the workpiece 16. Figure 4 The process involves handling the material to confirm the overall shape and dimensions of the workpiece 16. Furthermore, by comparing the dimensions with the design data, it is possible to confirm whether the dimensional accuracy meets the requirements. Below, we will discuss... Figure 4 The process will be explained.

[0059] In step S1, the spindle control unit 72a of the NC device 72 moves the spindle 1 toward the first measurement point A.

[0060] In step S2, at the moment when the position of the spindle 1 coincides with the first measuring point A, the control box 4 sets the coordinates of the spindle 1, that is, the coordinates of the first measuring point A (x, y). a y a It is stored in storage unit 4c as the first coordinate.

[0061] In step S3, the spindle control unit 72a of the NC device 72 moves the spindle 1 toward the second measurement point B.

[0062] In step S4, at the moment when the position of the spindle 1 coincides with the second measuring point B, the control box 4 sets the coordinates of the spindle 1, i.e., the coordinates of the second measuring point B (x, y, y), to... a y a It is stored in storage unit 4c as the second coordinate.

[0063] In step S5, the calculation unit 4d of the control box 4 calculates the distance between the first measurement point A and the second measurement point B based on the first coordinate and the second coordinate.

[0064] (Automatic replacement of shooting device 3 via ATC 9)

[0065] Figure 5This is a diagram showing an example of the structure of the ATC installed in the EDM machine according to Embodiment 1. Figure 6 This is a schematic diagram illustrating the situation where the imaging device and processing electrode are replaced by an ATC installed in the engraving EDM machine according to Embodiment 1.

[0066] like Figure 5 As shown, the ATC 9 includes a housing 9a, a rotating shaft 9b, a support 9c, and a guide 9d. The housing 9a stores unused processing electrodes 5 and the imaging device 3. The housing 9a is as follows... Figure 5 As shown, the processing electrode 5 and the imaging device 3 are suspended and stored. A rotating shaft 9b connects the housing 9a and the support 9c. The rotating shaft 9b is capable of rotating in the direction indicated by arrow C. The central axis of the rotating shaft 9b extends, for example, in the vertical or longitudinal direction. The direction indicated by arrow C is the circumferential direction centered on the position of the central axis of the rotating shaft 9b. Simultaneously with the rotation of the rotating shaft 9b in the direction of arrow C, the housing 9a also rotates in the direction of arrow C. The support 9c supports the housing 9a via the rotating shaft 9b. The support 9c is guided by a guide 9d and is capable of moving in the direction of arrow D. The guide 9d is a rod-shaped member extending in the direction of arrow D. Through the movement of the support 9c and the rotation of the rotating shaft 9b, the processing electrode 5 and the imaging device 3 automatically move to the position where the main shaft 1 is loaded. Furthermore, the direction of arrow D can be... Figure 1 The X-direction can be the same, or it can be different.

[0067] Normally, the machining electrode 5 is mounted on the spindle 1 of the engraving EDM machine 100 via the electrode chuck 2. By using the ATC 9, the machining electrode 5 can be automatically mounted and dismounted relative to the electrode chuck 2 by operating the program of the NC device 72. In addition, the machining electrode 5 removed from the spindle 1 of the engraving EDM machine 100 is returned to the housing 9a of the ATC 9. Using the automatic machining electrode changing mechanism implemented by the ATC 9, the imaging device 3 can also be automatically mounted and dismounted on the spindle 1 of the engraving EDM machine 100.

[0068] exist Figure 6 middle, Figure 6 (a) shows the state in which the imaging device 3 is mounted on the main shaft 1. Figure 6 (b) shows the state in which the machining electrode 5 is mounted on the spindle 1. Figure 6 As shown in (a), the imaging device 3 is connected to the spindle 1 via a connector. The first connector terminal 12 and the second connector terminal 13 are connected, thereby establishing the connector connection. As described above, in Embodiment 1, cables are not used to connect the imaging device 3 to the spindle 1.

[0069] On the other hand, the camera in existing processing apparatuses such as Patent Document 1 is wired to the recognition device or the computing device via a cable. Assuming that the camera of an existing processing apparatus such as Patent Document 1 can be automatically installed and removed via ATC 9, the following problems exist when moving the camera in and out of the ATC 9 case: the camera cable may become tangled with the spindle 1, be immersed in the processing fluid, or break.

[0070] In Embodiment 1, the imaging device 3 is connected to the main shaft 1 via a connector, thus avoiding the problems caused by the cable as described above. The connector connection will be explained below.

[0071] (Connector connection of shooting device 3)

[0072] Figure 7 This is a diagram showing an example of the connector connection structure provided in the EDM machine according to Embodiment 1. Figure 16 This diagram illustrates the wiring structure when a camera and a control box are installed in the EDM machine according to Embodiment 1. Furthermore, in Figure 16 To make the explanation easier to understand, diagrams of unnecessary wiring are omitted from the description. For example... Figure 1 , Figure 7 and Figure 16 As shown, the imaging device 3 is provided with a first connector terminal 12, and the main shaft 1 is provided with a second connector terminal 13. The first connector terminal 12 is male, and the second connector terminal 13 is female. By inserting the first connector terminal 12 into the recess of the female second connector terminal 13, the first connector terminal 12 and the second connector terminal 13 are electrically connected, and the connector connection is established. Alternatively, the first connector terminal 12 can be female, and the second connector terminal 13 can be male.

[0073] like Figure 7 and Figure 16 As shown, a second contact detection line 7b, a power line 41, and a signal line 45 pass through the interior of the first connector terminal 12 and the second connector terminal 13. When the imaging device 3 is mounted on the spindle 1, the second contact detection line 7b connects the imaging device cover 6 and the contact detection section 70. The power line 41 supplies power from the power supply 30 to the imaging device 3 via the control box 4. The signal line 45 transmits the imaging data obtained by the imaging device 3 to the control box 4.

[0074] Therefore, when the imaging device 3 is mounted on the spindle 1, the imaging device 3 and the control box 4, as well as the imaging device cover 6 and the contact detection unit 70, can be connected via a connector.

[0075] In Embodiment 1, as described above, the wired connection between the imaging device 3 and the control box 4 is automatically established via a connector connection. In Embodiment 1, under the control of the NC device 72, the connector connection is automatically performed while the imaging device 3 is mounted on the electrode chuck 2 mounted on the spindle 1, through program operation. Therefore, the user's workload can be reduced when changing the machining electrode 5 and the imaging device 3. Furthermore, in the case of automatic connector connection, for example, the first connector terminal 12 is supported by a component with high rigidity. This component is as follows: Figure 1 As shown, a component positioned between the first connector terminal 12 and the imaging device 3, which holds the first connector terminal 12, has an L-shape when viewed from above. Alternatively, both the first connector terminal 12 and the second connector terminal 13 can be supported by highly rigid components. This maintains the orientation of the first connector terminal 12, keeping it in a vertically extending state, so that even without user operation, the first connector terminal 12 is automatically loaded into the second connector terminal 13 as the imaging device 3 moves. Furthermore, as another method for automatically connecting the connectors, a robot can be used. In this case, a gripper such as a robot arm is provided in the ATC 9 to hold and transport the first connector terminal 12. Furthermore, the first connector terminal 12 is held by this gripper and transported to the second connector terminal 13, where it is then inserted into the second connector terminal 13 for connection.

[0076] Figure 8 This diagram illustrates the structure of the roller bearing in the second connector terminal of the engraving EDM machine according to Embodiment 1, designed to prevent it from falling off. Figure 7 and Figure 8 As shown, a roller 17 is provided on the second connector terminal 13 on the spindle 1 side. The roller 17 has a circular shape when viewed from the side. The roller 17 can be a cylindrical component or a spherical component. Additionally, as... Figure 7 As shown, a recess 18 for receiving the roller 17 is provided on the first connector terminal 12 on the side of the shooting device 3. The recess 18 is formed by a recess, as shown in the figure. Figure 7 As shown, the recess 18 is formed to be recessed inward from the surface of the first connector terminal 12. The recess 18 has a complementary shape to the roller 17. The recess 18 functions as a roller bearing for the roller 17. When the first connector terminal 12 is mounted on the second connector terminal 13, the roller 17 abuts against the inner wall of the recess 18, thereby hooking and preventing the first connector terminal 12 from falling off the second connector terminal 13.

[0077] like Figure 8As shown, a spring 19 is connected to roller 17. One end of spring 19 engages with roller 17, and the other end of spring 19 engages with terminal 13 of the second connector. Normally, as... Figure 8 As shown, the spring 19 does not retract, and becomes part of the roller 17, flying out from the inner wall of the second connector terminal 13 toward the space inside the second connector terminal 13. On the other hand, when the imaging device 3 is mounted on the spindle 1 via the electrode chuck 2, the roller 17 is pressed by the insertion pressure of the first connector terminal 12, and the spring 19 retracts. As a result, the entire roller 17 is completely housed within the second connector terminal 13. Thus, the first connector terminal 12 can be inserted into the second connector terminal 13. Moreover, once the insertion of the first connector terminal 12 into the second connector terminal 13 is completed, the spring 19 retracts and returns to its original state due to the elastic force of the spring 19, and the roller 17 is inserted into the recess 18, fixing the first connector terminal 12 to the second connector terminal 13. As described above, once the roller 17 is inserted into the recess 18, the roller 17 engages with the recess 18, thus preventing the first connector terminal 12 from falling out of the second connector terminal 13.

[0078] (Wiring structure when machining electrodes are mounted)

[0079] Figure 15 This is a diagram showing the wiring structure when machining electrodes are mounted in the EDM machine according to Embodiment 1. Furthermore, in Figure 15 In order to make the explanation easier to understand, some unnecessary wiring diagrams have been omitted from the description. For example... Figure 6 (b) and Figure 15 As shown, no connector is used when connecting the machining electrode 5. Power is supplied to the machining electrode 5 via the machining control unit 72c of the NC device 72 and the power supply unit 71 of the power board 10. Specifically, the NC device 72 uses the machining control unit 72c, as shown... Figure 13 As shown, a power supply command is output to the power supply unit 71 to instruct the power supply to the machining electrode 5. Therefore, the power supply unit 71 supplies power to the machining electrode 5 via the power line 47. The power line 47 is as follows... Figure 15 As shown, the machining electrode 5 and the power supply unit 71 are connected by passing through the interior of the spindle 1. The power supply to the drive unit 50 is provided by the power supply unit 71 using power from the power supply 30 via the power line 46. In addition, when the machining electrode 5 is mounted on the spindle 1, the second contact detection line 7b connects the machining electrode 5 and the contact detection unit 70.

[0080] (Contact detection function)

[0081] Figure 9This is a diagram illustrating the structure of the contact detection function in the EDM machine according to Embodiment 1. Figure 9 The image shows a contact detection circuit that detects the contact between the camera cover 6 of the camera device 3 and the workpiece 16.

[0082] To obtain images with sub-micron precision, the imaging device 3 needs to be close to the workpiece 16. Typically, existing EDM machines for engraving molds have a contact detection function to detect the contact between the processing electrode 5 and the workpiece 16. However, existing EDM machines for engraving molds lack this contact detection function. Therefore, when the imaging device 3 comes into contact with the workpiece 16, it can actually cause damage to both the imaging device 3 and the workpiece 16.

[0083] Therefore, in Embodiment 1, the contact detection circuit 7 between the machining electrode 5, unique to the EDM machine 100, and the workpiece 16 is also applied to the imaging device 3. For this purpose, in Embodiment 1, an imaging device cover 6 capable of communicating with the imaging device 3 is provided. Thus, as according to... Figure 9 As is known, when the workpiece 16 and the imaging device cover 6 come into contact, an electrical circuit is formed by the imaging device cover 6, the workpiece 16, the platform 21, the first contact detection line 7a, the contact detection unit 70, and the second contact detection line 7b. The contact detection unit 70 detects the contact between the workpiece 16 and the imaging device cover 6 by detecting the flow of current in the electrical circuit. Furthermore, when the contact is detected, the contact detection unit 70 instantaneously outputs a contact detection signal to the NC device 72. If the NC device 72 receives the contact detection signal, it outputs a command from the spindle control unit 72a to the drive device 50 that drives the spindle 1, causing an emergency stop to the operation of the spindle 1.

[0084] The operation is the same when the machining electrode 5 and the workpiece 16 come into contact. That is, when the workpiece 16 and the machining electrode 5 come into contact, an electrical circuit is formed by the machining electrode 5, the workpiece 16, the platform 21, the first contact detection line 7a, the contact detection unit 70, and the second contact detection line 7b. The contact detection unit 70 detects the contact between the workpiece 16 and the machining electrode 5 by detecting the flow of current through this electrical circuit. Moreover, when contact is detected, the contact detection unit 70 instantaneously outputs a contact detection signal to the NC device 72. If the NC device 72 receives the contact detection signal, it outputs an emergency stop command from the spindle control unit 72a to the drive device 50 that drives the spindle 1.

[0085] As described above, in Embodiment 1, a contact detection circuit 7 consisting of a first contact detection line 7a and a second contact detection line 7b is provided. Therefore, it is possible to detect not only the contact between the processing electrode 5 and the workpiece 16, but also the contact between the imaging device 3 and the workpiece 16. Thus, when the imaging device 3 contacts the workpiece 16, the contact detection unit 70 within the power board 10 can immediately detect the contact and cause the spindle 1 to stop immediately via the NC device 72. This minimizes damage to both the imaging device 3 and the workpiece 16.

[0086] (Connector connection of camera housing 6)

[0087] The imaging device cover 6 and the contact detection unit 70 need to be wired connected in the same way as the imaging device 3. The wired connection between the imaging device cover 6 and the contact detection unit 70 is preferably capable of automatic assembly and disassembly via a programmed operation. Therefore, in Embodiment 1, as described above, by... Figure 7 The connector shown is used to implement a wired connection between the imaging device cover 6 and the contact detection unit 70.

[0088] (Insulation function)

[0089] Figure 10 This is a diagram illustrating the structure of the insulating function in the EDM machine according to Embodiment 1. Figure 10 The diagram illustrates an insulation function that insulates the contact detection unit 70 within the power board 10 of the EDM machine 100 from the control box 4. In Embodiment 1, by providing this insulation function, it prevents the machine from being mistakenly detected as being in contact with the workpiece 16 when the imaging device 3 is mounted on the spindle 1, thus ensuring that the spindle 1 remains stationary.

[0090] Depending on the model of the imaging device 3, sometimes the ground of the electrical part 3b of the imaging device 3 is connected to the frame (not shown) of the imaging device 3. In this case, at the moment the imaging device 3 is mounted on the spindle 1, an electrical circuit is formed via the electrode chuck 2, the imaging device 3, the control box 4, the contact detection unit 70, and the spindle 1. If the workpiece 16 comes into contact with the imaging device 3, the contact detection unit 70 will always falsely detect. At this time, in the engraving EDM machine 100, the spindle 1 is in a state of emergency stop, and the movement of the spindle 1 is interlocked. To avoid this situation, in Embodiment 1, a ground 20 is provided in the imaging device 3 at a position that does not contact the frame, and the electrical part 3b of the imaging device 3 is connected to the ground 20. That is, the ground 20 does not make electrical contact with the frame of the imaging device 3 or the imaging device cover 6. As described above, in Embodiment 1, by providing the ground 20, insulation can be achieved between the contact detection unit 70 connected to the imaging device cover 6 and the control box 4 connected to the electrical part 3b of the imaging device 3. The grounding 20 is sometimes referred to as the insulating part. Thus, in Embodiment 1, when the imaging device 3 is mounted on the spindle 1, it is possible to prevent the contact detection unit 70 from mistakenly detecting that the workpiece 16 is in contact with the imaging device 3.

[0091] (Hardware Structure)

[0092] Here, the hardware structure of control box 4 will be explained.

[0093] In the control box 4 according to Embodiment 1, the power supply unit 4a, the image processing unit 4b, and the arithmetic unit 4d are implemented by a processing circuit. The processing circuit may be a processor and memory that execute programs stored in memory, or it may be dedicated hardware. The processing circuit is also referred to as a control circuit.

[0094] Figure 11 This is a diagram illustrating an example of the structure of a processing circuit in which the processing circuit of the control box according to Embodiment 1 is implemented by a processor and a memory.

[0095] Figure 11The processing circuit 90 shown is a control circuit, comprising a processor 91 and a memory 92. When the processing circuit 90 is composed of the processor 91 and the memory 92, its functions are implemented through software, firmware, or a combination of both. The software or firmware is described as a program and stored in the memory 92. In the processing circuit 90, the processor 91 reads and executes the program stored in the memory 92, thereby implementing the various functions. That is, the processing circuit 90 has a memory 92 used to store the program that ultimately executes the processing of the control box 4. This program can be described as a program used to cause the control box 4 to perform the various functions implemented by the processing circuit 90. This program can be provided through a storage medium containing the program, or through other units such as a communication medium.

[0096] The above procedure can be described, for example, as causing control box 4 to execute... Figure 4 The procedure for steps S2, S4, and S5. That is, the above procedure can be described as a procedure that causes the control box 4 to perform the steps of storing the first coordinate, storing the second coordinate, and calculating the distance between the first measurement point A and the second measurement point B based on the first coordinate and the second coordinate.

[0097] Here, processor 91 is, for example, a CPU (Central Processing Unit), processing device, arithmetic device, microprocessor, microcomputer, or DSP (Digital Signal Processor). Additionally, memory 92 is, for example, non-volatile or volatile semiconductor memory such as RAM (Random Access Memory), ROM (Read Only Memory), flash memory, EPROM (Erasable Programmable ROM), EEPROM (Electrically EPROM), magnetic disk, floppy disk, optical disk, compact disk, mini-disk, or DVD (Digital Versatile Disc).

[0098] Figure 12 This diagram illustrates an example of a processing circuit in which the processing circuit of the control box described in Embodiment 1 is constructed using dedicated hardware. Figure 12The processing circuit 93 shown may be, for example, a single circuit, a composite circuit, a programmable processor, a parallel-programmable processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or a combination thereof. The processing circuit 93 may be implemented in part by dedicated hardware and in part by software or firmware. As described above, the processing circuit 93 can implement the aforementioned functions using dedicated hardware, software, firmware, or a combination thereof.

[0099] PC 8, like control box 4, is... Figure 11 The processing circuit 90 shown or Figure 12 The processing circuit 93 shown is configured as follows. Similarly, the spindle control unit 72a, ATC control unit 72b, and machining control unit 72c of the NC device 72 are also configured, for example, by... Figure 11 The processing circuit 90 shown or Figure 12 The processing circuit 93 shown is configured as described. In these cases, the processing circuits 90 and 93 have the same structure as in the case of control box 4, so their description is omitted here.

[0100] (Effect)

[0101] As described above, in Embodiment 1, since the imaging device 3 can be mounted on the spindle 1, the surface shape and dimensions of the processed workpiece 16 can be confirmed without removing it from the platform 21. Therefore, even if the confirmation result indicates that additional processing of the workpiece 16 is required, the workload of reloading the workpiece 16 onto the platform 21 for changeover adjustments can be reduced. Furthermore, minor positional shifts caused by reloading the workpiece 16 can be prevented. Moreover, since the imaging device 3 is mounted on the spindle 1, it can move together with the spindle 1. Therefore, imaging of the workpiece 16 within a desired range, from a wide to a narrow range, can be achieved, expanding the focus adjustment area of ​​the imaging device 3.

[0102] Furthermore, in Embodiment 1, a grounding 20 is provided within the imaging device 3 at a location that does not contact the frame of the imaging device 3 or the imaging device cover 6. As described above, by connecting the electrical part 3b of the imaging device 3 to the grounding 20, which is different from the grounding 11, insulation is achieved between the control box 4 and the contact detection part 70 within the power board 10. Therefore, when the imaging device 3 is mounted on the spindle 1, it is possible to avoid forming an electrical circuit through the imaging device 3, control box 4, contact detection part 70, and spindle 1. As a result, it is possible to prevent the contact detection part 70 from falsely detecting that the workpiece 16 is in contact with the imaging device 3 when the imaging device 3 is mounted on the spindle 1. As a result, it is possible to avoid the situation where the movement of the spindle 1 is interlocked due to false detection, preventing the spindle 1 from moving. Therefore, after the imaging device 3 is mounted on the spindle 1, the imaging device 3 can move freely together with the spindle 1.

[0103] Furthermore, in Embodiment 1, the imaging device 3 has an imaging device cover 6, which is conductive. For example, due to user error or program malfunction, the imaging device 3 and the workpiece 16 may come into contact. In Embodiment 1, by providing a conductive imaging device cover 6, even if the workpiece 16 and the imaging device 3 come into contact, the contact detection unit 70 can immediately detect the contact based on the conduction state of an electrical circuit formed by the imaging device cover 6, the workpiece 16, and the contact detection unit 70. In addition, based on the detection result of the contact detection unit 70, the NC device 72 instantly stops the movement of the spindle 1, thus minimizing damage to the imaging device 3 and the workpiece 16.

[0104] Furthermore, in Embodiment 1, by using the ATC 9, the machining electrode 5 and the imaging device 3 can be automatically installed and removed relative to the spindle 1. The removed machining electrode 5 and imaging device 3 are stored in the housing 9a of the ATC 9. The housing 9a is separated from the machining tank, thus preventing oil fumes generated from the machining fluid from contaminating the machining electrode 5 and imaging device 3 stored in the housing 9a. As a result, it is possible to prevent dirt buildup on the lens 3a of the imaging device 3 caused by oil fumes, and to prevent deterioration of the internal substrate of the electrical part 3b of the imaging device 3 caused by oil fumes.

[0105] In Embodiment 1, the connection between the imaging device 3 and the control box 4, and the connection between the imaging device cover 6 and the contact detection unit 70, are made via a connector consisting of a first connector terminal 12 and a second connector terminal 13. It is assumed that the imaging device 3 and the control box 4, or the imaging device cover 6 and the contact detection unit 70, are connected via a wired connection using cables or the like. In this case, when the imaging device 3 is attached to or detached from the spindle 1, the cable may snag on the spindle 1 or the ATC 9, become tangled, or stretch and break. Furthermore, the cable may also become immersed in the processing fluid. In Embodiment 1, because a connector connection is used, these problems caused by cables do not occur.

[0106] The imaging device 3 acquires imaging data of the workpiece 16, thereby enabling the control box 4 to obtain the coordinates of the first measuring point A and the second measuring point B on the workpiece 16. Therefore, the dimensions of each part of the workpiece 16 can be easily measured. Using the PC 8, the user can confirm the image data 15 of the workpiece 16 in real time, thus allowing for the verification that the shape and dimensions of the workpiece 16 are accurate and precise.

[0107] If the camera described in Patent Document 1 is not applied to a general NC machine tool, but rather to the engraving EDM machine shown in Embodiment 1, the following problems will occur.

[0108] (1) Due to the oil fumes during the EDM process, the camera lens was dirtied and could not capture clear images.

[0109] (2) Due to the oil fumes during the EDM process, the internal substrate of the camera deteriorates and may fail.

[0110] (3) For example, even if the structure is designed to allow the camera to be detached, the connection between the camera and the NC machine tool is wired, making it difficult to handle the cable when changing the camera. As a result, the cable may break.

[0111] (4) The camera is not equipped with an emergency stop function when in contact, so the camera and the workpiece are in continuous contact and the camera or the workpiece may be damaged.

[0112] (5) For example, even if the camera is equipped with an emergency stop function upon contact, when the ground of the camera's internal board is connected to the camera's frame, the spindle will be in an emergency stop state the instant the camera is mounted on it. As a result, the spindle is fixed, the camera cannot be moved, the workpiece cannot be photographed within the desired range, and the camera's focus adjustment area is narrowed.

[0113] In contrast, in the EDM machine 100 of embodiment 1, as described above, all these problems (1) to (5) can be solved.

[0114] The structure shown in the above embodiments is an example, and it can also be combined with other known technologies, and various modifications described in the embodiments can also be combined. Without departing from the main idea, a part of the structure can be omitted or changed.

[0115] Explanation of the label

[0116] 1. Spindle, 2. Electrode chuck, 3. Imaging device, 3a. Lens, 3b. Electrical unit, 4. Control box, 4a. Power supply unit, 4b. Image processing unit, 4c. Storage unit, 4d. Calculation unit, 5. Machining electrode, 6. Imaging device cover, 7. Contact detection circuit, 7a. First contact detection line, 7b. Second contact detection line, 8. PC, 9. ATC, 9a. Box, 9b. Rotary axis, 9c. Support unit, 9d. Guide unit, 10. Power board, 11, 20. Grounding, 12. First connector terminal, 13. Second connector terminal, 15. Image data, 16. Workpiece, 16a. First edge, 16 b. 2nd edge, 17. Roller, 18. Recess, 19. Spring, 21. Platform, 30. Power supply, 40, 41, 46, 47. Power lines, 42, 45. Signal lines, 43, 44. Ground lines, 50. Drive unit, 60, 61. Image, 70. Contact detection unit, 71. Power supply unit, 72. CNC unit, 72a. Spindle control unit, 72b. ATC control unit, 72c. Machining control unit, 90, 93. Processing circuit, 91. Processor, 92. Memory, 100. Engraving die EDM machine, A. 1st measuring point, B. 2nd measuring point, C, D. Arrows.

Claims

1. A die-cutting electrical discharge machining (EDM) machine, characterized in that, have: spindle; A machining electrode, which can be detachably mounted on the spindle, processes the workpiece by non-contact discharge to the workpiece placed in an insulating machining fluid; An imaging device, which is interchangeable with the processing electrode and detachably mounted on the spindle, takes pictures of the workpiece after it has been processed by the processing electrode, and obtains imaging data representing the shape of the processed workpiece. A contact detection unit, which is connected to the main shaft, detects the contact when the imaging device is mounted on the main shaft and the workpiece comes into contact. NC device, which controls the movement and stopping of the spindle; as well as The control box uses power from an external power source to power the imaging device via the spindle, and receives the imaging data acquired by the imaging device via the spindle, performs image processing on the imaging data to generate image data. When the imaging device is mounted on the spindle, the contact detection unit and the control box are insulated so that an electrical circuit is not formed through the imaging device, the control box, the contact detection unit, and the spindle. When the contact is detected by the contact detection unit, the NC device causes an emergency stop to the movement of the spindle.

2. The engraving die electrical discharge machining machine according to claim 1, characterized in that, The imaging device has an imaging device cover that is mounted to cover the imaging device, is connected to the contact detection unit, and is conductive. When the imaging device is mounted on the spindle, the contact detection unit detects whether there is contact between the imaging device and the workpiece based on the conduction state of an electrical circuit formed by the imaging device cover, the workpiece, and the contact detection unit.

3. The EDM machine for engraving molds according to claim 2, characterized in that, have: The first connector terminal is disposed on the imaging device; as well as The second connector terminal, which is disposed on the spindle, establishes a connector connection when connected to the first connector terminal. The connection between the shooting device and the control box, and the connection between the shooting device cover and the contact detection part, are made through the connector.

4. The engraving mold electrical discharge machining machine according to any one of claims 1 to 3, characterized in that, It has an automatic tool changer that, in response to an externally input signal, changes the machining electrode and the imaging device for the spindle.

5. The engraving mold electrical discharge machining machine according to any one of claims 1 to 3, characterized in that, When the photographing device photographs the workpiece. When the NC device moves the spindle to align it with a pre-set first measuring point on the workpiece, the control box stores the coordinates of the spindle at the point where its position matches the first measuring point as the first coordinate. When the NC device moves the spindle to align it with a pre-set second measuring point on the workpiece, the control box stores the coordinates of the spindle when its position matches the second measuring point as the second coordinate. The control box calculates the distance between the first measurement point and the second measurement point based on the first coordinate and the second coordinate.

Images