JPWO2015079520A1 - Automatic cutting system using insert-changeable cutting tools - Google Patents

Abstract

The rotation angle to the unused portion when a part of the cutting edge of the insert becomes unsuitable for processing due to wear or the like is calculated from the processing conditions, and the insert is rotated based on the calculated angle. Therefore, an automatic cutting system that uses an insert-exchangeable cutting tool includes a control means that reads a machining program, a database that stores life test data and tool data, and an insert screw that loosens a screw that holds the insert on the cutting tool. A loosening mechanism, an insert rotation mechanism for rotating the insert, and an insert automatic rotation device having a control device for controlling the insert screw loosening mechanism and the insert rotation mechanism.

Description

  The present invention relates to an automatic cutting system, and more particularly, to an automatic cutting system using an insert exchange type cutting tool.

  In order to automate the cutting process, it is necessary to adjust the cutting position of the tool or replace the tool manually or automatically by detecting the wear of the tool with a visual or sensor. Further, it is necessary to automate a plurality of cutting processes of a work material by using the tool under optimum cutting conditions. Therefore, detection and replacement of tool wear is important.

  Patent Document 1 describes that the amount of tool wear is accurately predicted before machining from a low-speed cutting region to a high-speed cutting region instead of actually detecting tool wear. Therefore, the amount of tool wear is predicted from a prediction formula that has a term that affects the abrasive wear caused by hard inclusions in the work material and a term that affects the thermal diffusion wear caused by hard inclusions in the work material. ing. Thereby, the tool life can be determined in consideration of the influence of both the abrasive wear mainly occurring in the low and medium speed cutting region and the thermal diffusion wear mainly occurring in the high speed cutting region.

  Patent Document 2 describes an automatic rotating device that automatically rotates a round cutting insert used in an NC automatic machining system. In this publication, in order to easily and accurately adjust the rotational position of the round cutting insert, the screw part rotation provided with a hexagon wrench for tightening / loosening the screw hole formed in the cutting tool within the moving range of the machine tool Means and an insert rotating means for rotating the round cutting insert by a predetermined angle after loosening the hexagonal hole.

JP 2008-212454 A JP 2012-6119 A

  In the tool wear prediction method described in Patent Document 1, only the wear of a tool selected from predetermined machining conditions is predicted. For this reason, the tool to be used is a cutting tool in which the insert can be replaced, and there is no disclosure about reduction of man-hours in cutting by automatically replacing the insert in accordance with the amount of wear. That is, in a cutting system using a multi-function processing machine such as a machining center, a plurality of processing steps can be automatically executed as a series of operations, and the man-hour and work time are reduced by the entire automation. 1 does not consider such automation.

  Further, in the automatic rotating device described in Patent Document 2, a new machining position is set by rotating the worn insert by appropriately setting the amount of rotation of the abutment portion for rotating the insert from the control unit for the automatic rotating device. doing. However, in the automatic rotation device of Patent Document 2, the amount of rotation is set appropriately, and there is no disclosure about the detection of the position where wear has occurred. Therefore, the timing and angle at which the insert is rotated are not always optimal, and if the operator neglects to monitor the insert, the workpiece may be processed with a worn tool and a defect may occur. Moreover, there is a risk that the insert will be worn out and the insert may be broken and scattered. Furthermore, it is difficult to automatically and continuously execute a plurality of cutting processes.

  The present invention has been made in view of the above-described problems of the prior art, and its purpose is to predict the wear state of the cutting edge of the insert before processing, and to rotate the amount corresponding to the process of the insert based on the prediction. Alternatively, it is to automate a cutting process including a plurality of processes by automatically executing the replacement. This also makes it possible to shorten the cutting process.

  A feature of the present invention that achieves the above object is that an automatic cutting system using an insert-exchangeable cutting tool includes a control means for reading a machining program, a database for storing life test data and tool data, and cutting the insert into the cutting tool. An insert screw loosening mechanism for loosening a screw held in a tool; an insert rotation mechanism for rotating the insert; and an insert automatic rotation device having a control device for controlling the insert screw loosening mechanism and the insert rotation mechanism. The rotation angle and rotation time of the insert or the replacement time of the insert is determined from the life test data and the tool data stored in the database, and the control device determines the determined rotation angle and rotation of the insert. When, replace the insert Based on the period, it is to drive the insert automatic rotation device.

  Another feature of the present invention that achieves the above object is that an automatic cutting system using an insert exchange type cutting tool reads a machining program, extracts a machining condition from the read machining program, and life test data. And a step of calculating a rotation angle of the insert and a tool life with reference to a database storing tool data, and whether or not an unused cutting edge portion remains when the insert is rotated by the calculated rotation angle. And a step of processing with the unused cutting edge portion, and a step of determining whether the insert is automatically rotated or automatically replaced after the processing.

  According to the present invention, the machining conditions according to the machining process are acquired in advance, the tool life is predicted using the acquired machining conditions, and the amount of rotation of the cutting edge portion of the insert is only an amount according to the machining process. Therefore, the insert can be automatically rotated or exchanged according to the wear of the cutting edge portion of the insert, and the cutting process including a plurality of processes can be automated. In addition, the cutting process can be shortened.

It is a flowchart explaining the automatic cutting operation | movement using the automatic cutting system which concerns on this invention. It is a front view of one Example of an insert exchange type cutting tool. It is a perspective view which shows the cutting state using the cutting tool shown to FIG. 2A. It is an enlarged front view of the insert which the cutting tool shown in FIG. 2A has. It is a figure which shows the relationship between the flank wear width of an insert, and a tool life. It is a figure which shows the relationship between a cutting speed and the tool life of an insert. It is a flowchart explaining the insert automatic rotation operation | movement in FIG. It is a bottom view of the insert explaining the use condition of the conventional insert. It is a bottom view of the insert explaining the use condition of the insert concerning the present invention. It is a side development figure explaining the wear state in an insert. It is a perspective view of one example of an insert automatic rotation device with which the automatic cutting system concerning the present invention is provided. It is a perspective view of one Example of the automatic cutting system which has an insert automatic rotation apparatus shown to FIG. 8A. It is an expansion perspective view of one Example of the insert rotation mechanism which constitutes the insert automatic rotation device concerning the present invention. It is a longitudinal cross-sectional view of the insert rotation mechanism shown in FIG. 9A. It is a perspective view explaining automatic rotation of an insert using an insert rotation mechanism. It is an expansion perspective view of one Example of the insert screw loosening mechanism which comprises the insert automatic rotation apparatus which concerns on this invention. It is an example of the longitudinal cross-sectional view of the insert screw loosening mechanism shown to FIG. 10A. It is a flowchart explaining operation | movement of an insert automatic rotation apparatus.

  Hereinafter, some embodiments of an automatic cutting system according to the present invention will be described with reference to the drawings. In the following description, a machining center will be described as an example of an automatic cutting system. However, the automatic cutting system is not limited to a machining center, and can be applied to various automatic processing machines such as an automatic milling machine and an NC lathe.

  First, an outline of the automatic cutting system 100 will be described with reference to FIG. 8B. FIG. 8B is a perspective view of an embodiment of an automatic cutting system 100 including the insert automatic rotating device 50 according to the present invention.

  As shown in FIG. 8B, the automatic cutting system 100 of the present embodiment is a horizontal machining center, and a table 20 on which a workpiece is placed is movable in the longitudinal direction of the bed 83 on a bed 83 that extends in the horizontal direction. Is installed. A gate-shaped column 81 is arranged so as to straddle the bed 83. A main shaft portion 73 to which a cutting tool is attached is disposed on the upper side of the column 81 and extending in the short side direction of the bed 83. The base part of the main shaft part 73 is movable in the short side direction of the bed 83, and the cutting tool holding part of the main shaft part 73 is movable in the vertical direction.

  An ATC (automatic tool changer) 70 is attached to one side surface of the column 81 formed in a gate shape. The automatic tool changer 70 has a flat plate portion that forms the side surface of the column, and a chain 72 that is formed on the flat plate portion and holds and moves the exchange tool 71. The chain 72 forms a closed circuit with a bend, and is connected to an insert automatic rotating device 50 described later at a lower side portion. A control device for controlling the automatic insert rotation device 50 is attached to one end of the automatic insert rotation device 50.

  Next, the operation of the automatic cutting system 100 according to the present invention will be described with reference to FIG. FIG. 1 is a flowchart of cutting using the automatic cutting system 100. When the automatic cutting system 100 is activated, in step S1, a control means (not shown) included in the automatic cutting system reads an NC program necessary for the current machining from a CAM, a machine tool, an external computer, or the like.

  Next, in step S2, the control means extracts machining conditions from the read NC program. In the automatic cutting system 100, the cutting tool 1 having the replaceable round insert 3 is used. Therefore, the machining conditions include the shaft cutting ap (mm) and the cutting speed Vc (m / m) which is the rotational speed of the insert 3. min), a one-blade feed amount (mm / tooth), which is a speed in the tool machining direction per blade, in a rotating tool, and the like, and the material of the workpiece 4 is also a machining condition.

  Here, the state of the cutting with the insert-exchange-type cutting tool 1 will be described with reference to FIGS. 2A and 2B. FIG. 2A is a front view of the insert-exchangeable cutting tool 1 used in the automatic cutting system, and FIG. 2B is a perspective view of the insert-exchangeable cutting tool 1. A basic insert-exchangeable cutting tool 1 holds a body 1 mounted on a main shaft portion of an automatic cutting system 100, a plurality of inserts 3 positioned at a tip portion of the body 1, and the insert 3 in the body 1. An insert fastener 2 and a set screw 5 for fixing the insert fastener 2 to the body 1.

  When the body 1 rotates around the tool rotation axis 6, the plurality of inserts 3 attached to the tip of the body 1 cut the work material 4 at a peripheral speed, and the thickness direction of the work material 4 corresponds to the depth ap. To cut. At the same time, the workpiece 4 is cut by a diameter cut dr in the width direction of the workpiece 4.

  Returning to FIG. 1, since the machining conditions have been determined, the rotation angle β and the tool life Lt for rotating the insert 3 are determined in step S3. As a result of continuing the cutting process, when the insert 3 is worn and a predetermined amount of wear or more is seen, the round insert 3 provides a new cutting surface by rotating the insert 3 around the central axis of the party. . The rotation of the insert 3 will be described with reference to FIG. FIG. 3 is an enlarged front view of the front end portion of the body 1.

  When the body 1 rotates around the tool rotation axis 6, a part of the circumference of the circular insert 3 forms the work material 4 and the contact portion 7. The size of the contact portion 7 is determined by the cutting depth ap and the radius r of the insert 3, and the center angle of the contact portion 7 is β. The insert 7 is in contact with the work material 4 only in the range of the angle β, and is not in contact in the other range (360 ° -β). Therefore, when the wear of the insert 3 progresses, the insert 3 is rotated around its center by the angle β of the portion that has been in contact. This angle is called a rotation angle βi.

  That is, when a part of the cutting edge of the insert 3 is worn away by processing and becomes unsuitable for use, the insert 3 is rotated to a position where the unused portion cuts. Further, when the worn part advances and the rotated part becomes unsuitable for use, it is rotated to the next unused part. This rotation is sequentially executed, and the use is stopped when there is no unused portion in the entire circumference of the insert 3.

  In step S3, when the insert 3 is rotated as a result of wear of the insert 3, a range in which cutting by the worn portion does not occur after rotation is calculated. That is, the rotation angle βi of the insert 3 is calculated at a position where the wear part (contact range in the machining so far) does not hit the work material 4.

  The automatic cutting system 100 includes a database S4. In the database S4, the life test data acquired in advance and the type of the cutting tool 1 to be used are stored, and the database S4 is referred to in the process of step 3 above. Then, using the data of the referenced database S4, the tool life Lt under the machining conditions read in step S2 is calculated. Further, the diameter Dtool (mm) of the cutting tool 1, the number of blades tooth, and the radius r of the insert 3 are obtained from the type of the cutting tool 1.

On the other hand, the rotation angle βi of the cutting tool 1 is determined from the radius r of the insert 3 read from the database S4 and the shaft cut ap5 extracted in step S2. For example, when the cutting tool 1 shown in FIG. 3 is used, the wear of the insert 3 proceeds at the portion 7 in contact with the work material 4. The rotation angle βi at this time is obtained by the following equation (1).
βi = cos ⁻¹ ((r−ap) / r) (1)

In the NC program of the general-purpose NC machine, the number of rotations S (1 / min) per minute of the cutting tool 1 and the feed rate (mm / min) of the cutting tool 1 per minute are specified. However, since the tool life Lt changes according to the machining conditions, it is necessary to predict from the machining conditions according to each machining operation. The evaluation parameter of the tool life Lt is the cutting speed Vc (m / min), and is obtained by the equation (2) from the rotational speed S (1 / min) and the tool type.
Vc = π · D _tool · S / 1000 (2)
Here, D _tool is the diameter (mm) of the cutting tool 3 shown in FIG. 2A.

  The life test data stored in the database S4 for predicting the life of the cutting tool 1 includes, for example, the relationship between the tool life Lt and the flank wear width Ww (see FIG. 7C) of the insert 3, and the tool life Lt and the cutting speed Vc. There is a relationship. Further, as one of the determination methods of the tool life Lt, there is a method of determining the life when the flank wear width Ww of the insert 3 exceeds a predetermined width.

  4 and 5 show examples of data stored in the database S4. FIG. 4 is a graph showing an example of test data showing the relationship between the material removal volume Vs and the flank wear width Ww with the cutting speed Vc as a parameter. Tool diameter 2r = 32 mm, shaft cut ap = 1.0 mm, diameter cut dr = 15.5 mm, single blade feed amount = 0.08 mm / tooth, and cutting speed Vc = 1100 to 1500 m / min. This is a case where the ceramic material is cut down by the ceramic material insert 3 under dry conditions without coolant. The work material 4 is a Ni alloy.

For example, when the flank wear Ww of the insert 3 becomes Ww ≧ 2 mm, the tool life Lt is set. The tool life Lt can be easily obtained from the material removal volume Vs (cm ³ ) when the flank wear width Ww is 2 mm and the cutting amount per unit time (= cutting speed Vc × diameter cutting dr × axis cutting ap). .

  FIG. 5 is a graph showing a result obtained by experimentally determining the relationship between the cutting speed Vc (m / min) and the tool life time Lt (min). As shown in FIG. 5, the cutting speed Vc and the tool life Lt are in an inversely proportional relationship. Therefore, the tool life in the machining conditions read from the NC program shown in step S2 can be predicted from the data shown in FIGS. If a machining test is performed in the same manner under the conditions of different axis cutting ap, feed amount, and material of the work material 4, and the results are stored in the database S4, the lifetime can be predicted in a wider range.

  When the data on the machining conditions read from the NC program is not in the database S4, the data is closest to the data on the machining conditions read, and at least one of the cutting speed Vc, the feed amount Fs, and the axis cutting ap is severer than the machining conditions. Select data. If a desired machining condition cannot be obtained even when such a selection method is adopted, an alert is generated on the screen of a computer or machine tool. And it is good to notify an operator so that it may process with lower cutting speed Vc, feed amount Fs, and shaft cutting ap.

  In step S5, it is determined whether or not there is a usable part for the insert 3 of the cutting tool 1 used for processing. That is, it is confirmed whether only the unused portion of the insert 3 is correctly rotated and installed at the position where the workpiece 4 is processed. As a confirmation method, a method in which a camera (not shown) provided in the automatic cutting system 100 captures an image of the insert 3 and performs image processing to determine a worn portion can be applied.

  If there is an unused portion in the insert 3 and it can be used for subsequent processing, the process proceeds to step 6. In this step 6, when the subsequent machining process of the workpiece 4 includes a plurality of processes, the unused portion of the insert 3 is allocated to each process. If the subsequent process has only one process, an unused portion used in that process is allocated.

  In this embodiment, the rotation angle βi of the insert 3 is varied according to the processing conditions and processing steps. Therefore, in order to prevent an unused portion when replacing the insert 3, the total sum of several rotation angles βi is closest to 360 °, which is the entire circumferential angle of the cutting blade of the insert 3, and is 360 ° or less. Set to.

  In step S5, when it is determined that the insert 3 is set at a position that is not suitable for continuous use in the state where the wear of the insert 3 has progressed, the process proceeds to step S10. Then, the cutting tool 1 is replaced or the insert 3 is rotated by a predetermined angle βi. Then, it progresses to step S6.

  When the use part of the insert 3 has been assigned and the cutting tool 1 is set in the automatic cutting system 100 so that the insert 3 is used in the unused part, the process proceeds to step S7, and cutting is performed based on the NC program read in step S1. carry out. When the cutting process is executed in accordance with the NC program and the time for changing the assigned position of the insert 3 is reached, the process proceeds to step S8.

  In step S8, the insert 3 that has reached the tool life Lt is rotated. The tool life Lt and the rotation angle βi at this time are the values derived in step S3. Here, when the machining process is completed without reaching the tool life Lt, the tool may be used until the tool life Lt is reached in the next machining process. In this case, when the machining conditions are different, the tool life Lt is obtained assuming that the machining is performed under stricter machining conditions. Then, by replacing or rotating the insert 3 with the determined tool life Lt, the insert 3 can always be processed in a worn state suitable for processing.

  When one machining process is completed, in step S9, it is confirmed on the NC program whether or not all machining processes are completed by the completion of the machining process. If there are any remaining machining processes, the process returns to step S7 to execute the remaining machining processes.

  In the present embodiment, the tool life Lt is predicted from the life test data using the flank wear width Ww of the insert 3, but the method for predicting the tool life Lt is not limited to this. For example, the tool life can be predicted from the surface roughness of the work surface of the work material. In the present embodiment, a cutting tool having a round insert has been described. However, the tool is not necessarily limited thereto, and can be similarly applied to a turning tool.

  Next, the detailed example of the automatic rotation method of the insert 3 using the automatic cutting system 100 in the said step S3-S9 is demonstrated using FIG.6 and FIG.7A-7C. FIG. 6 is a flowchart showing an example of a method for automatically rotating the insert 3. 7A and 7B are side views of the insert 3, FIG. 7A is a diagram for explaining cutting surface assignment of the conventional insert 3, and FIG. 7B is a diagram for explaining cutting surface assignment of the insert 3 according to the present invention. . FIG. 7C is a development view of the peripheral surface of the insert 3, and is a development view as seen in the direction of arrow A in FIG. 7B.

  First, in step S11, each condition is read. The contents to be read are the usable portion of the cutting blade of the insert 3 and the number of cutting tools 1 to be used, the time required for automatically rotating the insert 3, and the worn insert 3 into the insert 3 whose cutting edge is not used. These are the insert replacement time required for replacement and the replacement time of the cutting tool 1.

  Here, the time for exchanging the cutting tool 1 is the time for exchanging the cutting tool 1 using the automatic tool changer (ATC) 70 attached as a standard to the machining center 100 or the cutting tool 1 using an apparatus according to the ATC70. This is the time required for replacement. When only exchanging the cutting tool 1 is executed manually, the time required for the operator to replace the cutting tool 1 is input.

  Next, in step S12, a portion to be processed in each processing step is assigned to the cutting edge of the insert 3 that can be used. At this time, the rotation angle βi for rotating the insert 1 is determined from the circumferential wear width of the cutting edge of the insert 1 to be used. A method for assigning the rotation angle will be described with reference to FIGS. 7A and 7B. The insert 3 has a cutting edge 8 at the periphery, and cutting is performed using the portion of the cutting edge 8. By continuing the cutting process, the cutting edge 8 is worn, and a worn portion 9 is formed on the cutting edge 8 part. Therefore, the insert 3 is rotated by a predetermined angle (rotation angle) βi.

Allocation method of a conventional rotational angle βi, as shown in FIG. 7A, and then pivot the insert 3 by a fixed angle of rotation beta _0. This is because the operator visually determines the rotation angle βi, and the operator manually rotates the insert 3. That is, regardless of the processing conditions, for example, the rotation angle βi is designated in advance as a constant value by using the cutting blade 8 of one insert 3 only three to four times. As a result, since all of the cutting blades 8 are rotated or replaced without being used up, the number of inserts 3 used is increased and the tool cost is increased.

  On the other hand, if it is intended to extend the tool life Lt, it is necessary for the operator to specify the timing for replacing or rotating the insert 3 every time. When the tool life Lt adapted to each process is designated, the operator needs to monitor the cutting tool 1 and grasp the tool life Lt for each process, which increases the burden on the worker.

  In order to eliminate the above problems, if the cutting tool 1 is replaced at the same timing in all steps regardless of the processing conditions, the insert 3 is replaced without being used up to the original tool life. The number of rotations and the number of replacements of the cutting blade 8 increase. Therefore, the insert 3 to consume increases. Alternatively, processing may occur due to processing with an amount of wear exceeding the use limit of the insert 3. For these reasons, it is difficult to apply the conventional method for replacing the insert 3 to the automatic replacement of the insert 3.

  On the other hand, in the insert 3 shown in FIG. 7B, the rotation angle βi is adjusted only for the wear portion 9 of the insert 3. The wear width in the circumferential direction of the insert 3 is determined from the shaft cut ap and the radius r of the insert 3 shown in FIG. The rotation angle βi is obtained from the equation (1). Here, the axis cut ap is read when the NC program is read in step S1 of FIG. On the other hand, the radius r of the insert 3 is stored in the database S4 of FIG. Using these values, the rotation angle βi of the insert 3 is automatically calculated.

For example, when the portion of the cutting edge 8 of the insert 3 is suitable for use at 360 ° in the circumferential direction, the sum of the rotation angles β ₁ , β ₂ ,..., Βn in each process is 360 degrees or less. Then, the combination closest to 360 ° is selected. And it allocates in the order which can be processed most efficiently including the time of replacement | exchange of the insert 3, and replacement | exchange of the cutting tool 1. FIG. Thereby, it is possible to utilize almost all the cutting edges 8 without wasting the insert 3.

  Since the tool life Lt for determining the use limit of the insert 3 is stored in the database S4 in FIG. 1, machining can be performed with an appropriate tool life Lt in all processes. This eliminates the need for the operator to rotate or replace the insert 3 each time, and the tool life Lt is automatically determined, thus enabling stable unmanned machining.

  In step S13 of FIG. 6, the number of replacements of the insert 3 is read from the rotation angle βi of the insert 3. Then, the timing of replacement, such as whether the insert 3 is rotated or replaced, or the cutting tool 1 is replaced, is set. In step S11, since the rotation time of the insert 3, the replacement time of the insert 3, the time for replacement of the tool 1, and the number of tools 1 are set in advance, the machining lead time is the shortest from the time required for the replacement and rotation. Set the machining process.

  For example, when a plurality of the same cutting tools 1 are provided and the rotation time of the insert 3 is longer than the replacement time of the tool 1, the replacement of the tool 1 is executed with priority over the rotation of the insert 3. That is, instead of rotating the insert 3 when the insert 3 is worn and the tool life Lt is reached, the cutting tool 1 is replaced using an automatic tool changer (ATC) 70 or the like. Then, the cutting tool 1 with the worn insert 3 is retracted to a pallet (not shown) of the automatic tool changer (ATC) 70, and the worn portion of the cutting tool 1 having the insert 3 worn during machining with the new cutting tool 1 is rotated. Let

  As a result, in processing using the cutting tool 1 having the round insert 3, there is no loss in processing time, and processing can be performed efficiently. In this embodiment, a plurality of machining steps are set in consideration of the number of cutting tools 1, the rotation time of the insert 3, the replacement time of the insert 3, and the replacement time of the cutting tool 1, so that the machining lead time is shortened. Can be processed with high efficiency.

  Next, in step S14, machining is performed based on the machining process set in step S13. Furthermore, in step S15, the machining is executed until the timing considering the tool life Lt. When the designated timing for stopping the processing is reached, it is determined in step S16 whether or not the insert 3 is automatically rotated or automatically replaced or the cutting tool 1 is automatically replaced.

  When the insert 3 is automatically rotated or automatically replaced, the process returns to step S14 and the machining is performed again. If the wear of the insert 3 has not yet reached the tool life Lt, and the automatic rotation or automatic replacement of the insert 3 or the replacement of the cutting tool 1 is not necessary, the process proceeds to step S17, and whether or not the set machining has been completed. Judging.

  If it is determined in step S17 that all the set processing steps have been completed, the processing ends. If it is determined that all the set machining steps have not yet been completed, the process returns to step S14 and machining is performed until the tool life is reached.

  In the present embodiment, an example is shown in which the cutting edge position of the insert 3 is changed to a position that is not worn by using the rotation angle βi of the round insert 3. However, for example, there is a case where the insert 3 has an unevenness in advance, and the insert 3 can be rotated only by the interval unit of the unevenness. In such a case, the rotation angle βi may be specified by a multiple of the interval between the irregularities, and the present invention can be applied to applications other than round inserts.

  Another embodiment according to the present invention will be described with reference to FIGS. 8A to 11. The present embodiment relates to an automatic rotating device 50 that automatically rotates the insert 3. FIG. 8A is a perspective view of the automatic insert rotation device 50. The automatic insert rotation device 50 includes an X-axis table 13 having a drive axis in the X-axis direction, a Y-axis table 12 having a drive axis in the Y-axis direction that is orthogonal to the X-axis, and both the X-axis and the Y-axis. And a plurality (two in this embodiment) of Z-axes (supports) 14 extending in the vertical direction. On one end side of the X table 13, a control device 60 for controlling the automatic insert rotation device 50 is provided.

  An insert rotation mechanism 15 that rotates the insert 3 is attached to one Z axis 14, and a set screw 5 of the insert 3 that is screwed to the cutting tool 1 with a set screw 5 is attached to the other Z axis. A screw loosening device 16 for loosening is attached. Each Z-axis 14 has a base portion 14b that fits into a groove formed in the X-axis table 13, and a column portion that extends vertically upward from the base portion 14b. The column portion has a groove portion 14c that extends in the vertical direction. Is formed. The insert rotation mechanism 15 and the screw loosening device 16 are fixed by a fixing means (not shown) using the groove portion 14c of the Z-axis 14.

  The control device 60 drives and controls the Y table 12, the X table 13, and the Z axis 14, and the screw loosening device 16 and the insert rotation mechanism 15 are placed on the bottom of the chain 72 of the automatic tool changer 70 as shown in FIG. 8B. Move. Then, the Z-axis 14 is positioned at a position where the cutting tool 1 replacement or rotating insert 3 is carried.

  The position of the cutting tool 1 is recognized by a plurality of sensors (not shown). The sensor only needs to be able to recognize at least the position of the cutting tool 1 and the position of the insert 3. For example, a method of processing an image captured by a camera is used. The sensor may be installed at an arbitrary position on the automatic insert rotation device 50. When the insert 3 is automatically rotated by the machine tool itself, positioning means for the cutting tool 1 and the insert 3 may be provided on the machine tool side.

  9A to 9C are diagrams illustrating the automatic insert rotation mechanism 15 according to the third embodiment. 9A is a perspective view of the automatic insert rotation mechanism 15, FIG. 9B is a longitudinal sectional view of FIG. 9A, and FIG. 9C is a perspective view for explaining the rotation of the insert 3.

The automatic insert rotation mechanism 15 includes a housing 17. On one end side of the housing 17, a rectangular mounting plate portion 17 a that abuts on the Z-axis 14 is formed, and a cylindrical portion is continuous with the mounting plate portion 17 a. Groove portions 17 _b1 and 17 _b2 extending in the X-axis direction are formed in the columnar portion in parallel in the vertical direction. The groove portions 17 _b1 and 17 _b2 extend to the back side of the cylindrical portion of the housing 17.

A gear 21 and a pinion 20 that mesh with each other are disposed on the inner side of the cylindrical portion of the housing 17. The rack 19 a meshes with the pinion 20, and the rack 19 b meshes with the gear 21. An insert rotating rod 18a is attached to the rack 19a, and an insert rotating rod 18b is attached to the rack 19b. The insert rotating rods 18 a and 18 b are respectively held in grooves 17 _b1 and 17 _b2 formed in the housing 17, and end portions protrude from the housing 17. Furthermore, the contact improvement material 24 is attached to the protrusion side edge part of insert rotation rod 18a, 18b.

  A servo motor 22 is attached to the back side of the mounting plate portion 17 a of the housing 17, and the rotation shaft of the servo motor 22 extends into the housing 17. And it connects with the rotating shaft of the pinion 20. An encoder 23 is attached to the rotation shaft of the servo motor 22.

  In the automatic insert rotation mechanism 15 configured as described above, by driving the servo motor 22, the two insert rotation rods 18a and 18b are alternately translated in the X direction as shown in FIG. Rotate in the direction. That is, when the servo motor 22 is driven, the pinion 20 connected to the servo motor 22 is rotationally driven, and the gear 21 meshing with the pinion 20 is rotationally driven in the opposite direction to the pinion 20. When the pinion 20 and the gear 21 are driven to rotate, the racks 19a and 19b meshing with each other move in the opposite directions of the X axis, and the insert rotating rods 18a and 18b attached to the racks 19a and 19b also translate in the opposite directions. Moving.

  Here, the rotation amount of the servo motor 22 is detected by the encoder 23, and the rotation angle of the servo motor 22, that is, the translational movement amount of the two insert rotation rods 18a and 18b is controlled using the detected value of each encoder. The The contact improving material 24 attached to the tips of the insert rotating rods 18a and 18b is provided to improve friction with the insert 3 and improve contact, and uses rubber or the like.

  10A and 10B are views for explaining the screw loosening mechanism 16 of the insert in the third embodiment. FIG. 10A is a perspective view of the screw loosening mechanism 16, and FIG. 10B is a longitudinal sectional view of the screw loosening mechanism 16.

  The screw loosening mechanism 16 has an outer shape similar to the insert rotation mechanism 15. That is, it has a housing 26 composed of a rectangular mounting plate portion 26b that abuts the Z-axis and a cylindrical portion 26a continuous to the mounting plate portion 26b, and an encoder is connected to the rotating shaft on the back side of the mounting plate portion 26b. A servo motor 28 to which 28 is attached is disposed. A columnar rotating member 30 is disposed inside the cylindrical portion 26 a of the housing 26, and a rotating shaft 27 a of a servo motor 27 is connected to the mounting plate portion 26 b side of the rotating member 30.

  On the other hand, a plurality of wrench rotating motors 29a to 29d are attached to the periphery of the rotating member 30 at substantially equal intervals, and wrench adapters 31a to 31d are attached to output shafts of the wrench rotating motors 29a to 29d. It has been. The wrench adapters 31a to 31d are formed in a shape in which one end sides of the rod-like wrench 25a to 25d are fitted. The other ends of the rod-like wrench 25a to 25d protrude from the open side of the housing 26 in the (−) Y-axis direction. Note that a plurality of wrench 25a to 25d that are prepared have different nominal sizes or are frequently used.

  As shown in FIG. 2A, the insert 3 attached to the cutting tool 1 is fixed by a set screw 5. Therefore, the set screw 5 fixing the insert 3 is loosened using the screw loosening mechanism 16. Depending on the type of cutting tool, the shape and size of the set screw 5 for fixing the insert 3 are different. Therefore, as shown in FIG. 10, a plurality of wrenches 25 a to 25 d are arranged around the rotating member 30.

  In the screw loosening mechanism 16, since it is necessary to select the wrench 25a to 25d suitable for the set screw 5, the wrench 25a used by rotating the rotating member 30 with the servo motor 27 for positioning the wrench 25a to 25d. Select. Further, in order to facilitate replacement of the wrench 25a to 25d, the wrench 25a to 25d is fitted to the wrench adapter 31a to 31d. When the set screw 5 is loosened or tightened by the wrench 25a to 25d, the motors 29a to 29d installed at the roots of the wrench 25a to 25d are driven.

  When the set screw 5 of the insert 3 is loosened, if the wrench 25b to 25d other than the selected wrench 25a does not interfere with the cutting tool 1, it is not necessary to rotate the rotating member 30. In that case, the servo motor 27, the encoder 28, and the rotating member 30 can be omitted. Further, when it is not necessary to replace the wrench 25a to 25d and the same wrench 25a to 25d is always used, the wrench adapters 31a to 31d are omitted and the wrench 25a to 25d is directly connected to the servo motor shaft. Good. As the wrench 25a to 25d, it is preferable to use a hexagon wrench, a square wrench, a hexagon box wrench or the like.

  FIG. 11 is a flowchart showing the rotation operation of the insert 3 using the automatic insert rotation device 50. In step S18, a sensor (not shown) confirms the positions of the cutting tool 1 and the insert 3. Next, in step S19, the screw loosening mechanism 16 of the automatic insert rotating device 50 is moved to the position of the cutting tool 1 held in the exchange and rotating position of the automatic tool changing device 70, and the insert screw loosening mechanism is moved to the position of the set screw 5. 16 is positioned.

  In step S20, the wrench 25a to be used is engaged with the set screw 21 and fixed. Next, at step 21, the wrench rotating motor 29a is rotationally driven, and the wrench 25a loosens the set screw 5 fixing the insert 3.

  Proceeding to step S22, it is confirmed by a confirmation means (not shown) whether the set screw 5 is loose. As a confirmation method, for example, when the load torque, which is the output of the wrench rotating motor 29a, becomes a predetermined value or less, it is determined that the set screw 5 has been loosened. If it is confirmed that the set screw 5 has been loosened, the process proceeds to step S23 where the control device 60 drives the X-axis table 13, the Y-axis table 12, and the Z-axis 14 of the automatic insert rotation device 50, and the screw loosening mechanism 16 is moved to the next. Retreat to a position that does not interfere with the machining process. If the set screw 5 is not loosened, the process returns to step S20, and the operation of loosening the set screw 5 is executed again.

  Since the set screw 5 has been loosened, the process proceeds to step S24. The control device 60 of the automatic insert rotation device 50 controls the drive of the X-axis table 13, the Y-axis table 12, and the Z-axis 14, and the cutting tool in which the insert rotation mechanism 15 is held at the replacement and rotation position of the automatic tool changer 70. 1 is moved to the position of the insert 3.

  In step S25, the insert 3 is rotated by the rotation angle βi specified in step S3 of FIG. Since the insert 3 is rotated, in step S26, whether or not the insert 3 is rotated by a predetermined amount is confirmed by performing image processing on imaging information such as a camera (not shown).

  If it can be confirmed that the insert 3 is rotated by a predetermined amount, the process proceeds to step S27, and the control device 60 drives and controls the X-axis table 13, the Y-axis table 12, and the Z-axis 14, and the insert rotation mechanism 15 is processed. Evacuate to a position where it does not get in the way. When the retraction of the insert 3 is completed, the automatic rotation operation of the insert 3 is completed. If it cannot be confirmed in step S26 that the insert 3 is rotated by a predetermined amount, the process returns to step S25, and the insert 3 is rotated again until the predetermined amount of rotation is reached.

  According to each of the above embodiments, when a part of the insert used for the cutting tool became unsuitable for processing due to wear or the like, the rotation angle of the insert up to the unused portion that was not worn was calculated from the processing conditions and calculated. Since the insert is rotated based on the angle, cutting can be performed under appropriate conditions. In addition, it is possible to realize an automatic insert rotation system that automatically rotates an unused portion of the cutting blade to a cutting position. And even if processing conditions change sequentially, all the cutting edges on the outer periphery of the insert can be used up without waste. Furthermore, since all inserts can be automatically rotated without manual intervention, there is no difference in the amount of rotation caused by the difference in operator experience, and the cutting system can be automated.

  In addition, this invention is not limited to the said Example, Various modifications are possible. A part of the configuration of one embodiment can be replaced by the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Furthermore, it is also possible to add, delete, and replace other configurations for a part of the configuration of each embodiment. Accordingly, all modifications that come within the true spirit and scope of the present invention are included in the claims.

DESCRIPTION OF SYMBOLS 1 ... Cutting tool (body), 2 ... Insert fastener, 3 ... Insert, 4 ... Work material, 5 ... Set screw, 6 ... Tool rotating shaft, 7 ... Contact part, 8 ... Insert cutting blade, 9 ... Wear part 12 ... Y-axis table, 13 ... X-axis table, 14 ... Z-axis (support), 14b ... Base portion, 14c ... Groove portion, 15 ... Insert rotation mechanism, 16 ... Insert screw loosening mechanism, 17 ... Housing, 17a ... Installation Plate part, 17 _b1 , 17 _b2 ... Groove part, 18a, 18b ... Insert rotating rod, 19a, 19b ... Rack, 20 ... Pinion, 21 ... Gear, 22 ... Servo motor, 23 ... Encoder, 24 ... Contact improver 25a-25d ... wrench, 26 ... housing, 26a ... cylindrical part, 26b ... mounting plate part, 27 ... servo motor, 27a ... servo motor shaft, 28 ... encoder, 29a-29 d ... Wrench rotation motor, 30 ... Rotating member, 31a to 31d ... Wrench adapter, 50 ... Insert automatic rotation device, 60 ... Control device, 70 ... ATC (automatic tool changer), 71 ... Tool, 72 ... Chain, 73 ... main shaft, 81 ... column, 82 ... table, 83 ... bed, 100 ... automatic cutting system (machining center), ap ... axial cut (depth of cut), dr ...径切_{inclusive, D tool ...} tool diameter, L T _... tools Life time, r ... insert radius, Vc ... cutting speed, Vs ... material removal volume, W ... insert width, Ww ... flank wear width, β ... contact angle, β _{0 to} β _i ... rotation angle.

Claims (10)

  An automatic cutting system that uses an insert-exchangeable cutting tool, a control means for reading a machining program, a database for storing life test data and tool data, and an insert screw for loosening a screw for holding the insert in the cutting tool A loosening mechanism, an insert rotating mechanism for rotating the insert, an insert screw loosening mechanism, and an insert automatic rotating device having a control device for controlling the insert rotating mechanism, wherein the control means stores the life test stored in the database. From the data and the tool data, the rotation angle and rotation time of the insert or the replacement time of the insert is determined, and the control device is based on the determined rotation angle and rotation time of the insert and the replacement time of the insert. The inserter Automatic cutting system using an insert exchangeable cutting tool, characterized in that for driving the automatic rotation device.   The insert is a round insert, and the control means calculates the wear width in the circumferential direction of the cutting edge portion of the insert from the dimensions and cutting speed of the insert under the cutting conditions read from the machining program, and calculated 2. An automatic cutting system using an insert-exchangeable cutting tool according to claim 1, wherein an unused position rotated by the wear width is set as a new cutting position.   2. The insert replacement type cutting according to claim 1, wherein the control means predicts the timing of rotating the insert from insert life test data stored in the database and machining conditions read from the program. Automatic cutting system using tools.   The control means sets the machining step based on the number of tools to be used, the time for rotating the insert, the time for exchanging the insert, and the time for exchanging the tool. An automatic cutting system using the insert-exchangeable cutting tool according to 1.   The insert automatic rotating device includes: an insert rotating mechanism that rotates the insert held in contact with the insert by a predetermined amount; and an insert screw loosening unit that loosens a screw that holds the insert on the tool. The insert replacement according to claim 1, further comprising: a mechanism, an X-axis table and a Y-axis table for positioning the insert rotation mechanism and the insert screw loosening mechanism on the cutting tool, and a plurality of Z axes. Automatic cutting system using a cutting tool.   The insert rotation mechanism is attached to one of the Z axes, and has a pair of gears, a rack that meshes with each of the pair of gears, and a contact portion that is attached to each rack and contacts the insert at the tip. A pair of rods and a motor coupled to one of the gears, and driving the motor causes the pair of rods to move in opposite directions to rotate the insert. Item 6. An automatic cutting system using the insert-exchangeable cutting tool according to Item 5.   The insert screw loosening mechanism is attached to the other Z-axis, and is a rotating member in which at least one wrench suitable for the size of the locking means for fixing the insert to the tool is arranged around the periphery. A first motor that rotationally drives each wrench, and a second motor that rotationally drives the rotating member, and the control device drives the second motor to select the wrench selected as the insert. 6. The insert-replaceable cutting tool according to claim 5, wherein positioning is performed and the first motor is driven to lower the wrench to loosen a screw of a locking means for locking the insert. Automatic cutting system.   An automatic cutting system using an insert-exchangeable cutting tool, wherein a step of reading a machining program, a step of extracting machining conditions from the read machining program, and a database storing life test data and tool data are referred to above. Calculating a rotation angle of the insert and a tool life, determining whether or not an unused cutting edge portion remains when the insert is rotated by the calculated rotation angle; and An automatic cutting system using an insert-exchangeable cutting tool, characterized by comprising a step of processing at a blade portion and a step of determining whether the insert is automatically rotated or automatically replaced after the processing.   9. The automatic cutting system using an insert-exchangeable cutting tool according to claim 8, wherein the machining program includes a plurality of machining steps, and the rotation angle is changed according to each machining step.   9. The automatic cutting system using an insert-exchangeable cutting tool according to claim 8, wherein the rotation angle of the insert is a circumferential angle of the insert determined from a relationship between the insert radius and a shaft cut.

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