JP2020082136A - Machine tool - Google Patents

Abstract

To provide a machine tool that can improve product manufacturing efficiency in a case of using a raw material that likely causes internal defect.SOLUTION: A machine tool 10 equipped with a cutting mechanism that cuts a raw material 102 comprises: the cutting mechanism 12 that has a non-destructive testing instrument 28 that detects internal defect of the raw material without destructing the material, a table 16 for holding the raw material 102 and a tool spindle 14 for holding a tool for cutting the raw material 102, which cuts and removes at least portion of the raw material 102 in order to repair the internal defect detected by the non-destructive testing instrument 28; a defect repairing instrument 30 that repairs the defect by supplementing materials to the cut and removed portion of the raw material 102 or stirring materials surrounding the cut and removed portion; and a control device 32 that controls driving of the non-destructive testing instrument 28, the cutting mechanism 12 and the defect repairing instrument 30.SELECTED DRAWING: Figure 1

Description

The present specification discloses a machine tool including a cutting mechanism for cutting a material.

In a machine tool having a cutting mechanism, that is, a so-called cutting machine, a product is manufactured by cutting a material. Here, some of the materials used for such cutting have internal defects. For example, castings are often used as a raw material for large products, but it is known that such castings are likely to have cavities called cavities inside.

Since the porosity occurs inside the casting, it cannot be visually recognized from the outside. Therefore, after cutting without recognizing the cavities, the cavities may appear on the processed surface and the presence of the cavities may be noticed. In this case, since the processed product obtained by the cutting process does not satisfy the standard as a product, the cutting process is wasted.

Therefore, it is conceivable to inspect the internal defects of the material before processing by using a nondestructive inspection device or the like. However, in this case, operations such as transporting the material to the inspection device, inspecting the material by the inspection device, and transporting the material from the inspection device to the machine tool are required, resulting in extra steps and labor. In particular, castings are often used for large-sized products, but transporting the materials for such large-sized products has been a heavy burden on workers.

Therefore, in some cases, it has been proposed to provide a machine tool with a detection device for detecting an internal defect in the material. For example, Patent Document 1 discloses that a lathe, which is a type of machine tool, is provided with ultrasonic flaw detection means for inspecting a chilled roll (material) for a casting defect (a cavity). In this lathe, when a casting defect is detected by ultrasonic flaw detection means, the outer wall of the casting defect is marked with chalk. According to the technique of Patent Document 1, since the casting defect is inspected on the machining line, the machining and the inspection can be easily switched.

JP-A 61-175563 JP-A-6-710 JP, 2008-151710, A

However, in Patent Document 1, although the detection of the internal defect is examined, the repair of the detected internal defect is not sufficiently examined. Therefore, in the technique of Patent Document 1, when an internal defect is detected in the material, the material needs to be discarded or transported to another device capable of repairing the defect. As a result, in Patent Document 1, it was not possible to sufficiently improve the efficiency in manufacturing a product by cutting a material that may cause internal defects such as a casting.

In Patent Document 2, a machine tool that uses a cup-type cutter is provided with a non-contact measuring device that measures a workpiece in a non-contact manner, so that the workpiece can be inspected without removing it from the chuck. Depending on the inspection result, There is disclosed a technique for performing a correction process with a cup cutter as it is. However, the technique of Patent Document 2 is merely a technique for inspecting and correcting the state of the work surface after processing, and is not a technique capable of dealing with internal defects of the material.

Further, Patent Document 3 discloses a method of inspecting the wall thickness of a cast product by repeatedly performing a step of cutting a completed cast product and a configuration of measuring a cut plane in three dimensions without contact. ing. However, in Patent Document 3, the finished product is cut (destructed) to inspect the wall thickness, and not only the internal defect of the cast product is repaired, but also the internal defect is detected. Not disclosed.

As described above, conventionally, there has been no machine tool capable of detecting and repairing an internal defect in a material. As a result, it was not possible to sufficiently improve the product manufacturing efficiency when using a material that is likely to cause internal defects.

In view of this, the present specification discloses a machine tool that can improve product manufacturing efficiency when a material that easily causes internal defects is used.

A machine tool disclosed in the present specification is a machine tool having a cutting mechanism for cutting a material, and a nondestructive inspection device for detecting an internal defect of the material without destroying the material, and the material. A workpiece holding device for holding a workpiece, and a tool holding device for holding a tool for cutting the material, wherein the material is for repairing an internal defect detected by the nondestructive inspection device. A cutting mechanism that cuts and removes at least a part of the material, a defect repair device that repairs the material by filling the material in the material that has been removed by cutting, or by agitating the material around the material that has been removed by cutting. A destructive inspection device, the cutting mechanism, and a control device that controls driving of the defect repair device are provided.

Since the machine tool includes the nondestructive inspection device and the defect repair device, the inspection and repair of the internal defect of the material and the product processing using the cutting mechanism can be continuously performed. In addition, when repairing an internal defect, it is necessary to remove the material by cutting it. However, since the cutting mechanism of the machine tool can be used for this cutting removal, the internal defect can be efficiently repaired. As a result, the product manufacturing efficiency can be improved when using a material that easily causes internal defects.

In this case, the control device may store the defect detection result by the nondestructive inspection device and the position and orientation of the nondestructive inspection device at the time of defect detection as defect information in association with each other.

With such a configuration, the position and size of the internal defect can be grasped, and removal of the periphery of the internal defect and repair of the internal defect can be efficiently performed.

Further, in this case, the control device acquires the outer shape information of the material based on the measurement result of measuring the material using a sensor or the CAD data of the material stored in advance, and the outer shape information and the defect information are acquired. A drive program for the cutting mechanism and the defect repair device for defect repair may be generated based on

By generating a cutting mechanism for defect repair and a drive program for the defect repair device in the control device, the internal defects can be repaired more efficiently.

Further, in this case, the control device determines whether or not each of the internal defects detected based on the outer shape information, the defect information, and the product shape information needs to be repaired, and the internal defect that is determined to be repaired. Only the cutting mechanism and the defect repair device may be repaired.

With such a configuration, the work of removing and repairing unnecessary internal defects becomes unnecessary, so that the working time as a whole can be shortened.

Further, when the control device can prevent the internal defect from being exposed on the product surface by shifting the reference point of the material of the product shape, the reference point of the product shape without repairing the internal defect. The cutting mechanism may be caused to shift to perform product processing.

With such a configuration, it is possible to reduce internal defects to be repaired, shorten the time required for removal and repair, and shorten the overall work time.

Furthermore, a robot having a plurality of articulated arms provided in the processing chamber may be further provided, and the nondestructive inspection device may be attached to the robot as an end effector of the robot.

With such a configuration, the material can be inspected from various positions, so that the internal defect can be detected more reliably.

Further, the nondestructive inspection device may be an ultrasonic flaw detector or a radiation transmission tester. With this configuration, the internal defect can be detected without adversely affecting the material.

Further, the defect repairing device may include at least one of a layered modeling machine, a welding machine, and a friction stir reformer. With such a configuration, the removed portion can be reliably repaired.

Further, the tool holding device includes a tool spindle for rotating and holding a rolling tool, and the defect repair device is a stirring tool attached to the tool spindle instead of the rolling tool, and the material A friction stir reformer for performing the friction stir reforming may be included.

With such a configuration, it is not necessary to separately provide a device for rotating and holding the stirring tool, so that it is possible to reduce the size and cost of the entire machine tool.

According to the machine tool disclosed in the present specification, product manufacturing efficiency can be improved when a material that easily causes internal defects is used.

It is a schematic front view of a machine tool. It is a block diagram showing a schematic structure of a machine tool. It is a figure which shows an example of a raw material. It is a figure which shows a mode that the material of FIG. 3A is cut and removed. It is a figure which shows a mode that the material of FIG. 3C is restored. It is a figure which shows an example of a raw material. It is a figure which shows a mode that the material of FIG. 4A is cut and removed. It is a figure which shows a mode that the material of FIG. 4C is restored. It is a figure which shows an example of a raw material. It is a figure which shows a mode that the material of FIG. 5A is cut and removed. It is a figure which shows a mode that the material of FIG. 5C is restored. 6 is a flowchart showing a flow of inspecting, removing, and repairing a material. It is a flowchart which shows the flow of evaluation of an internal defect. It is a figure which shows an example of a raw material. It is a figure which shows a mode that the reference point of the product shape was shifted in the material of FIG. 8A.

Hereinafter, the configuration of the machine tool 10 will be described with reference to the drawings. FIG. 1 is a schematic front view showing the configuration of the machine tool 10. Further, FIG. 2 is a block diagram showing a configuration of the machine tool 10. The machine tool 10 is a cutting machine that manufactures a product by cutting the material 102 into a specified product shape. In the following, the machine tool 10 will be described as a machining center that performs rolling machining, in particular, as a portal machining center suitable for machining large-sized products. However, the technique disclosed in the present specification may be applied to other machine tools as well as a machining center as long as it has a cutting mechanism. Therefore, the technology disclosed in this specification may be applied to a lathe for performing turning, a grinder for performing grinding, and a combined machining machine in which these are combined, in addition to a machining center.

The machine tool 10 is provided with a cutting mechanism 12 for cutting the material 102. The cutting mechanism 12 includes a table 16 that holds the material 102, and a tool spindle 14 that holds the tool 100. The tool spindle 14 functions as a tool holding device and holds the rolling tool 100 in rotation. The tool spindle 14 is held by a ram 18 so as to be movable up and down, and the ram 18 is held by a saddle 20. The saddle 20 is movable along a cross rail 22 extending in the horizontal direction (Y direction), and the cross rail 22 is vertically movable along a column 23. The table 16 functions as a work holding device, on which the material 102 is placed and fixed. The table 16 is supported by a bed 17 fixedly installed on the ground and movable in the horizontal direction (X direction).

When processing a product, the material 102 is cut by rotating the tool 100 at a high speed and moving the tool 100 relative to the material 102. Here, it is known that the material 102, particularly the material 102 used in a large-sized product, has an internal defect. For example, in a large product, a casting is often used as the material 102. However, this casting may have voids inside, so-called cavities, during the manufacturing process. Since such a porosity cannot be visually recognized from the outside, it often cannot be recognized before the product is processed. Therefore, after cutting without recognizing the cavities, the cavities may appear on the processed surface and the presence of the cavities may be noticed. In this case, since the processed product does not satisfy the standard as a product, the cutting work is wasted.

Therefore, conventionally, it is considered to inspect the internal defect of the material 102 before processing. However, conventionally, a defect inspection device (for example, a nondestructive inspection device) that detects an internal defect has been provided outside the machine tool 10. Therefore, in order to inspect whether there is an internal defect, a defect inspection device for the material 102 is used. And the inspection of the material 102 by the defect inspection apparatus, and the operation of transferring the material 102 from the defect inspection apparatus to the machine tool 10, resulting in extra steps and troubles. In particular, castings are often used for large-sized products, and transporting the material 102 for such large-sized products has been a heavy burden on the operator. Therefore, conventionally, it is often the case that a part of a plurality of materials 102 is not inspected for defects but is inspected by sampling. However, since the locations and shapes of internal defects (cast holes) differ depending on the solid, the sampling inspection cannot prevent the above-mentioned problems. Further, conventionally, when an internal defect that cannot be ignored is found by inspection, the material 102 must be discarded, and the material 102 is wasted. As a result, conventionally, the production efficiency when manufacturing a product using a material (for example, a casting) that may cause internal defects was low.

Therefore, in the machine tool 10 disclosed in this specification, in order to further improve the production efficiency of products, in addition to the cutting mechanism 12, a nondestructive inspection device 28 for detecting an internal defect and an internal defect are repaired. The defect repair device 30 is provided.

The nondestructive inspection device 28 detects a defect inside the material 102, for example, a porosity. As the nondestructive inspection device 28, for example, an ultrasonic flaw detector or a radiation transmission tester can be used. The nondestructive inspection device 28 is attached to the moving mechanism 24. The moving mechanism 24 changes the position and posture of the nondestructive inspection device 28, and is a multi-joint type robot 26 having a plurality of arms jointed to each other in this example. The nondestructive inspection device 28 is attached to the end of the arm as an end effector of the robot 26. As described above, by attaching the nondestructive inspection device 28 to the robot 26, the position and orientation of the nondestructive inspection device 28 can be freely changed, and the material 102 can be inspected from various positions and orientations. Further, in this example, the robot 26 is installed on the tool spindle 14. With such a configuration, the movable range of the robot 26, and thus the nondestructive inspection device 28, can be expanded, and defects can be detected from various positions.

The end effector attached to the robot 26 may be replaced as appropriate. Therefore, when inspecting the internal defect of the material 102, the non-destructive inspection device 28 is mounted on the robot 26 as an end effector, and when measuring the outer shape of the material 102, the robot 26 is contact-type as an end effector. Alternatively, a non-contact type three-dimensional measuring device may be attached.

In addition, in this example, the nondestructive inspection device 28 is attached to the moving mechanism 24, specifically, the robot 26. However, if the internal defect of the material 102 can be detected, the nondestructive inspection device 28 is positioned. The posture may be fixed.

The defect repair device 30 cooperates with the cutting mechanism 12 to repair an internal defect portion. That is, as will be described in detail later, when the nondestructive inspection device 28 finds a defect that cannot be overlooked inside the material 102, the control device 32 causes the cutting mechanism 12 to cut and remove the periphery of the location where the internal defect occurs. The defect repairing device 30 repairs by filling the material at the cut and removed portion or stirring the material around the cut and removed portion. Examples of the defect repairing device 30 include a layering machine for stacking and forming materials in layers, a welding machine for melting and joining the materials, and a peripheral material by pressing a stirring tool rotated at a high speed on the base material. A friction stir reformer that stirs can be used.

The defect repair device 30 is provided so as to be movable with respect to the material 102. For example, the defect repair device 30 may be attached to a moving body 29 that can move independently of the tool spindle 14. As another form, the defect repair device 30 may be attached to the tool spindle 14 instead of the tool 100.

The control device 32 is a computer including a CPU that performs various calculations and a memory 36 that stores various programs and data. The control device 32 further has a communication function, and can exchange various data such as a machining program (NC program) with other devices. The control device 32 may include, for example, a numerical control device that constantly calculates the positions of the tool 100 and the material 102. Further, the control device 32 may be a single device or may be configured by combining a plurality of arithmetic devices.

The control device 32 controls the drive of the table 16 and the tool spindle 14 when the material 102 is cut by the cutting mechanism 12 in order to obtain the product shape. Further, as will be described later, the control device 32 also controls the drive of the nondestructive inspection device 28, the cutting mechanism 12, and the defect repair device 30 in order to detect, remove, and repair the internal defect of the material 102. The exchange of data relating to the detection, removal, and repair of this defect will be described with reference to FIG. In the following, among the cutting processes by the cutting mechanism 12, the cutting process for removing internal defects from the material 102 is referred to as “removal process”, and the cutting process for generating a product shape from the material 102 is referred to as “product processing”. To distinguish between the two.

A product processing program is input to the control device 32 in advance. The product processing program is an NC program including the movement loci of the tool 100 and the material 102 when processing the product. Further, product CAD data indicating a product shape is also input to the control device 32 in advance. The product processing program and the product CAD data are generated in advance by an external device and input to the control device 32.

Further, the control device 32 acquires the outer shape information 40 indicating the outer shape of the material 102 prior to the detection of the internal defect. The control device 32 may acquire the outer shape information 40, for example, by reading CAD data indicating the shape of the material 102. As another form, the control device 32 may acquire the outer shape information 40 based on the detection result of the outer shape sensor 38 provided in the machine tool 10. The outer shape sensor 38 is not particularly limited as long as it can detect the outer shape of the material 102. Therefore, the outer shape sensor 38 may be a touch probe type three-dimensional measuring machine that contacts and measures the outer shape of the object, or a non-contact type tertiary that measures the outer shape of the object in a non-contact manner using laser or ultrasonic waves. It may be a former measuring machine.

The control device 32 determines the movement route of the nondestructive inspection device 28 based on the obtained outer shape information 40. That is, in order to detect the internal defect of the material 102, it is necessary to drive the moving mechanism 24 and change the nondestructive inspection device 28 to various positions and postures. The control device 32 calculates, based on the outer shape information 40, a movement route that allows the nondestructive inspection device 28 to detect defects in the entire range of the material 102 without the nondestructive inspection device 28 or the robot 26 interfering with the material 102. ..

The robot 26 (moving mechanism 24) is provided with a sensor 39 that detects the moving amount (rotating amount) of each arm. The detection value of the sensor 39 is sent to the control device 32 at any time. The controller 32 calculates the current position and orientation of the nondestructive inspection device 28 based on these detected values.

The detection result of the nondestructive inspection device 28 is also sent to the control device 32. The control device 32 stores the defect information 42 in association with the defect detection result and the position and orientation of the nondestructive inspection device 28 at the time of defect detection.

When removing and repairing the internal defect, the control device 32 generates a removal machining program P1 and a repair machining program P2 based on the obtained defect information 42 and outer shape information 40. The removal processing program P1 is a drive program (NC program) of the cutting mechanism 12 necessary for removing the periphery of the internal defect. The repair processing program P2 is a drive program for the defect repair device 30 necessary to repair the removed portion. By driving the cutting mechanism 12 and the defect repair device 30 according to these programs P1 and P2, internal defects of the material 102 are removed and repaired.

Next, how to inspect, remove, and repair the internal defect 104 of the material 102 will be described with reference to FIGS. FIG. 3A is an image view of the material 102 having four internal defects 104a to 104d inside. In FIG. 3A, the chain double-dashed line indicates the product outline. In the example of FIG. 3A, inside the material 102, internal defects 104a that do not overlap the product, internal defects 104b that overlap the product surface, and small internal defects 104c that are internal to the product, There are large internal defects 104d located inside the product.

Of these internal defects, the internal defect 104a at a position that does not overlap with the product does not pose a problem because it is removed in the process of processing the product even if left alone. Further, among the defects located inside the product, the small internal defect 104c does not have a large adverse effect on the quality of the product, so that there is no problem in leaving it. On the other hand, the internal defect 104b overlapping with the surface of the product is exposed to the outside when the product is formed, and significantly reduces the value as the product. Even inside the product, the large internal defect 104d may reduce the strength of the product.

However, since all of these internal defects 104a to 104d are hidden inside the material 102, they cannot be visually observed. Therefore, in this example, the presence or absence of such an internal defect 104 is detected and repaired as necessary prior to processing the product. Specifically, the control device 32 drives the robot 26 and the nondestructive inspection device 28 to detect the position and size of the internal defect 104. Subsequently, the control device 32 evaluates the detected internal defect 104 and determines whether or not the repair is necessary. There are various conceivable judgment criteria. For example, an internal defect 104b that overlaps the outer surface of the product and an internal defect 104d that is inside the product and has a size larger than the standard are determined to be repaired. Good.

When the internal defect 104 to be repaired can be identified, the control device 32 drives the cutting mechanism 12 to cut and remove the internal defect 104 to be repaired. In this example, since the internal defects 104b and 104d are to be repaired, the material 102 is cut and removed to a height position where the internal defects 104b and 104d can be removed as shown in FIG. 3B.

If the internal defects 104b and 104d to be repaired can be removed, subsequently, the control device 32 drives the defect repair device 30 to repair the cut and removed portion. In the example of FIG. 3, a layered modeling machine 50 is used as the defect repair device 30. The additive manufacturing machine 50 restores the removed portion by stacking the material on the removed portion. At this time, it is not necessary to fill the material in all the cut and removed portions, and it is sufficient to fill the material only in the portions necessary for product formation as shown in FIG. 3C.

Further, in the above description, all the material at the same height position as the internal defect 104 to be repaired is cut and removed, but only the peripheral portion of the internal defect 104 may be cut and removed. That is, when the internal defect 104 is present on the surface of the product as shown in FIG. 4A, only the periphery of the internal defect 104 may be cut and removed as shown in FIG. 4B. A welder 52 may be used as the defect repair device 30. In this case, as shown in FIG. 4C, the portion removed by cutting is repaired by overlay welding by the welding machine 52.

Further, as the defect repairing device 30, a friction stir reformer 54 may be used as shown in FIG. The friction stir reformer 54 stirs and reforms the surface material of the raw material. Specifically, the friction stir reformer 54 presses a cylindrical stirring tool 55 having a small projection called a probe 55a at the tip against the material surface while rotating at high speed, and presses the probe 55a into the material. The raw material 102 is heated by frictional heat between the side surface of the probe 55a and the lower surface of the shoulder portion of the stirring tool 55, loses plastic deformation resistance, causes material flow in a form dragged by rotation of the stirring tool 55, and is stirred. .. When the internal defect 104 is repaired by friction stir reforming, as shown in FIG. 5B, the material is cut and removed right above the internal defect 104 so that the probe 55a can reach the position of the internal defect 104. After that, as shown in FIG. 5C, the stirring tool 55 is rotated at a high speed, and the stirring tool 55 is pressed against the periphery of the internal defect 104 to stir the material around the internal defect 104.

The friction stir reformer 54 may be provided independently of the tool spindle 14, but may utilize the tool spindle 14. That is, as is clear from the above description, the holding device for the stirring tool 55 is required to have high rigidity that can rotate the stirring tool 55 at high speed and can withstand the plastic deformation resistance of the raw material. Although such a holding device is large and tends to be expensive, the tool spindle 14 satisfies these conditions. Therefore, if the stirring tool 55 is attached to the tool spindle 14 instead of the rolling tool 100 to perform friction stir reforming, it is not necessary to separately provide a tool holding device for friction stir reforming. The space and cost can be reduced.

Next, a flow of repairing the internal defect 104 will be described with reference to FIGS. 6 and 7. FIG. 6 is a flowchart showing the flow of repairing the internal defect 104, and FIG. 7 is a flowchart showing the flow of defect evaluation processing.

The control device 32 executes the process shown in FIG. 6 before starting the product processing. Specifically, the control device 32 first acquires the outer shape information 40 indicating the outer shape of the material 102 before product processing (S10). The outer shape information 40 may be acquired in advance as CAD data, or may be calculated based on the detection result of the outer shape sensor.

Next, the control device 32 calculates the movement route of the nondestructive inspection device 28 based on the obtained outer shape information 40 (S12). That is, a movement route that allows the nondestructive inspection device 28 and the robot 26 to inspect the entire material 102 with the nondestructive inspection device 28 without interfering with the material 102 is obtained. When the movement route is obtained, the internal defect 104 is inspected (S14). Specifically, the control device 32 moves the nondestructive inspection device 28 according to the movement route to bring the detection signal (ultrasonic wave, radiation, radar, etc.) from the nondestructive inspection device 28 close to the surface of the material 102. Send and receive. The detection result of the nondestructive inspection device 28 is sent to the control device 32 at any time. At the time of this detection, the control device 32 calculates the position (detection position) of the nondestructive inspection device 28 at any time based on the movement amount (rotation amount of each arm) sent from the robot 26. The control device 32 stores, as defect information, information in which the obtained detection result and the detection position are associated with each other (S16).

When the defect information is obtained, subsequently, the control device 32 evaluates whether each internal defect 104 needs to be repaired (S18). To evaluate the internal defect 104, the control device 32 first reads the product CAD data, the outer shape information 40, and the defect information 42 (FIG. 7, S30). Then, the position and size of the internal defect 104 are obtained from the defect information 42. When the material 102 has a defect, the control device 32 determines whether or not one internal defect 104 is in a position overlapping with the product (S34). That is, the control device 32 specifies the range of the material 102 that becomes the product, based on the outer shape information 40 and the product CAD data. Further, the control device 32 identifies the position of the internal defect 104 with respect to the material 102 based on the outer shape information and the defect information 42. The control device 32 determines whether the specified position overlaps with the product range.

As a result of the determination, when the internal defect 104 overlaps with the product, it is determined that the repair is unnecessary (S42). On the other hand, when the internal defect 104 overlaps with the product, the control device 32 subsequently determines whether the internal defect 104 overlaps with the product surface (S36). When it overlaps with the product surface, the internal defect 104 is exposed to the outside by processing the product. Therefore, it is determined that repair is necessary regardless of the size of the internal defect 104 (S40). On the other hand, when the internal defect 104 overlaps with the product but does not overlap with the product surface, that is, when the internal defect 104 is located inside the product, the control device 32 controls the size of the internal defect 104. Is compared with a predetermined allowable value (S38). This allowable value can be determined based on a strength standard, a weight standard, etc. required for the product.

As a result of the comparison, when the size of the internal defect 104 exceeds the allowable value, the control device 32 determines that the internal defect 104 needs to be repaired even if the internal defect 104 is inside the product (S40). On the other hand, when the size of the internal defect 104 is equal to or smaller than the allowable value, the internal defect 104 is not exposed to the outside of the product, and thus it is determined that repair is unnecessary (S42). When the evaluation of one internal defect 104 is completed, the next internal defect 104 is evaluated by the same procedure. When all the internal defects 104 have been evaluated, the process proceeds to step S20 (FIG. 6).

In step S20, the control device 32 generates a removal machining program P1 and a repair machining program P2. The removal machining program P1 is a machining program (NC program) required for removing the internal defect 104 that needs to be repaired. The repair processing program P2 is a drive program for the defect repair device 30 necessary to repair the removed portion.

If the two machining programs P1 and P2 can be generated, the control device 32 drives the cutting mechanism based on the machining program P1 for removal to cause the periphery of the internal defect 104 to be cut and removed (S22). Subsequently, the control device 32 drives the defect repair device 30 based on the repair program P2 to repair the internal defect 104 by filling the material in the removed portion or stirring the periphery of the removed portion (S24).

The repair process of the internal defect 104 is completed by the above procedure. Then, if the internal defect 104 of one material 102 can be repaired, the control device 32 directly processes the material 102 to manufacture a product.

That is, according to this example, the internal defect 104 of the material 102 can be detected, removed, and repaired, and the product processing can be continuously performed in the same machine tool 10. As a result, it is not necessary to convey the material 102 on the way, and the work can be simplified. Further, according to this example, when the internal defect 104 that cannot be ignored exists, the internal defect 104 is removed and repaired on the spot. As a result, the material 102 having the internal defect 104 can be effectively used, and the disposal of the material 102 can be effectively suppressed.

The configuration described so far is an example, and at least a non-destructive inspection device that detects a location of an internal defect of the material, a cutting mechanism that removes and removes at least the periphery of the internal defect, and a location that has been removed by cutting is repaired. And other defect repairing device, the other configurations may be appropriately changed. For example, in the above-described example, the nondestructive inspection device 28 is movable, but if the entire material 102 can be inspected at one place, the movement mechanism 24 for moving the nondestructive inspection device 28 may be omitted. The moving mechanism 24 is not limited to the robot 26, and may be another mechanism such as a linear movement mechanism.

Further, in the present example, the necessity of repairing the detected internal defect 104 is determined based on the size of the internal defect 104 and the position with respect to the product, but it may be determined based on other criteria. For example, regardless of the size of the internal defects 104, all the internal defects 104 that overlap with the product may be determined to be repair targets. As another form, all the internal defects 104 having a certain size or more may be determined to be repaired regardless of their positions.

As another form, the necessity of repair may be determined based on whether the internal defect 104 can be dealt with by changing the reference point of the product. That is, even if there is an internal defect 104 on the surface of the product as shown in FIG. 8A, if the reference point for the material 102 of the product shape is changed as shown in FIG. In some cases it can be located in. In such a case, instead of removing and repairing the internal defect 104, the reference point for the material 102 of the product shape may be changed. That is, when the material 102 has an internal defect 104 remaining without being repaired, the reference point of the product shape may be changed so that the residual internal defect 104 is not exposed on the product surface. With such a configuration, the internal defect 104 does not need to be removed or repaired, so that the lead time can be shortened by these times.

Further, in the above description, only the mechanism that performs the rolling process is illustrated as the cutting mechanism 12, but the cutting mechanism 12 can be used for the turning process and the grinding process as long as a part of the material 102 can be removed. But it is okay. Further, the defect repairing device 30 may be in a form other than the additive manufacturing machine, the welding machine, and the friction stir reformer as long as the defect can be repaired.

10 machine tools, 12 cutting mechanisms, 14 tool spindles, 16 tables, 17 beds, 18 rams, 20 saddles, 22 cross rails, 23 columns, 24 moving mechanisms, 26 robots, 28 non-destructive inspectors, 29 moving bodies, 30 defects Repair device, 32 control device, 36 memory, 38 outline sensor, 40 outline information, 42 defect information, 50 additive manufacturing machine, 52 welder, 54 friction stir reformer, 55 stirring tool, 55a probe, 100 for cutting Tool, 102 Material, 104 Internal defect.

Claims (9)

A machine tool having a cutting mechanism for cutting a material,
A nondestructive inspection device for detecting an internal defect of the material without destroying the material,
A work holding device for holding the material, and a tool holding device for holding a tool for cutting the material, the cutting mechanism for repairing an internal defect detected by the nondestructive inspection device. A cutting mechanism for cutting and removing at least a part of the material,
A defect repair device that repairs the material by filling the material in the portion removed by cutting or stirring the material around the portion removed by cutting, of the material,
A control device that controls driving of the nondestructive inspection device, the cutting mechanism, and the defect repair device;
A machine tool comprising: The machine tool according to claim 1,
The control device associates a defect detection result by the non-destructive inspection device and a position and orientation of the non-destructive inspection device at the time of defect detection and stores them as defect information.
A machine tool characterized by that. The machine tool according to claim 2, wherein
The control device acquires outer shape information of the material based on a measurement result of measuring the material using a sensor or CAD data of the material stored in advance, and detects a defect based on the outer shape information and the defect information. Generating a drive program for the cutting mechanism and the defect repair device for repair,
A machine tool characterized by that. The machine tool according to claim 3,
The control device determines whether or not each of the internal defects detected based on the outer shape information, the defect information, and the product shape information is required to be repaired, and only the internal defects determined to be repaired are subjected to the cutting. A machine tool which is repaired using a mechanism and the defect repair device. The machine tool according to any one of claims 1 to 4,
The control device shifts the reference point of the product shape without repairing the internal defect when the internal defect can be prevented from being exposed on the product surface by shifting the reference point of the material of the product shape. A machine tool characterized by causing the cutting mechanism to perform product processing. The machine tool according to any one of claims 2 to 5, further comprising:
A robot provided with a plurality of articulated arms provided in the processing chamber,
The nondestructive inspection device is attached to the robot as an end effector of the robot,
A machine tool characterized by that. The machine tool according to any one of claims 1 to 6,
The machine tool, wherein the nondestructive inspection device is an ultrasonic flaw detector or a radiation transmission tester. The machine tool according to any one of claims 1 to 7,
The machine tool, wherein the defect repairing device includes at least one of an additive manufacturing machine, a welding machine, and a friction stir reformer. The machine tool according to claim 8,
The tool holding device includes a tool spindle that holds a rolling tool in rotation,
The defect repair device includes a friction stir reformer for performing friction stir reforming of the material with a stirring tool attached to the tool spindle instead of the rolling tool.
A machine tool characterized by that.

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