JPWO2016199591A1 - Processing machine control device and processing machine control method - Google Patents

Abstract

A control device (10) for processing a workpiece (107) in accordance with a processing program and varying and controlling a control value of the processing machine (100) according to an override value, wherein the override value is set according to a processing load value. The maximum setting value (KF) of the machining load value (NP) for each of the first setting unit (4) that changes to the upper limit value (OR-OL) of (OR) and the machining location (Q1 to Q3) of the workpiece (107). ) Becomes a target load value (TP), the second setting unit (6) having a temporary upper limit (K-OR-OL) as an upper limit (OR-OL), and the machining load value (NP) is a machining threshold. A determination unit (2) that changes the override value (OR) to the initial override value (F-OR) when (PT) is exceeded.

Description

  The present invention relates to a processing machine control apparatus and a processing machine control method for controlling a control value in response to a change in a machining load value.

  Conventional processing machine control devices and processing machine control methods are constantly required to improve machining efficiency in order to reduce costs and shorten delivery times. When machining a workpiece having a variation in shape such as casting or forging, it is necessary to set a larger number of machining times in consideration of the case where the machining allowance is maximized due to the variation of the workpiece. Therefore, air cut time in which nothing is cut occurs at a portion where the machining allowance of the workpiece is small, and a method for shortening the air cut time has been demanded.

  In order to solve this problem, in Patent Document 1, the shape of the workpiece is measured in advance before machining, and the machining program is changed according to the measurement result, thereby shortening the air cut time.

  However, as in Patent Document 1, a pre-measurement requires a measurement time, and is limited to a workpiece that can be measured.

There are two specific methods for measuring a workpiece, a contact type and a non-contact type.
The contact type is a method of recognizing the coordinates of the workpiece surface by bringing a probe having means for detecting coordinates into contact with the workpiece and detecting the contact. Although it is highly accurate, there is a problem that it takes a long time to touch the workpiece from a distant position when the workpiece is irregularly shaped so that the probe is not broken and is indefinite.

  The non-contact type is a method of measuring the position of a workpiece by irradiating light such as an LED or LD from a sensor having means for detecting coordinates and detecting the reflected light or transmitted light with a light receiving element (for example, (See Patent Document 1). Although the detection time is shorter than that of the contact type, there is a problem that the material and surface properties of the work are limited due to detection by optical means, the problem that the sensor is weak against dirt and the detection accuracy is low, and the sensor itself is expensive. There was a problem that.

  As a method for solving this, for example, in Patent Document 2, a target load is set in advance, and the feed speed and the rotation speed are changed so that the spindle load value interlocked with the machining load falls within the range of the target load value. Air cut time is shortened by load control. In this way, since measurement and control are performed in real time, prior measurement is not required as in Patent Document 1, and it can be performed by detecting current or power without any work restrictions. The cost is lower than that of the sensor.

JP 2013-18109 A JP 2005-205517 A

  In the conventional processing machine control device and processing machine control method, when machining load control is introduced, if the feed rate and the rotational speed are increased without limit, problems of machining accuracy and tool life occur. Therefore, an upper limit value is set for how much these can be increased.

  Actually, since the shape of the workpiece varies, it is necessary to actually machine a plurality of workpieces, check the tool life, and determine the "upper limit value of feed speed" that provides an appropriate machining time and tool life. .

  Therefore, when the "workpiece shape variation" itself changes, there is a high possibility that the tool will be damaged if the machining allowance for the workpiece increases, and conversely, if the workpiece becomes smaller, the machining efficiency can be further increased. There was a problem that the machining efficiency was relatively lowered.

  In addition, in order to prevent these problems, it is necessary to perform machining with a sufficient number of workpieces, and there is a problem that it takes time to introduce machining load control.

  The present invention has been made to solve the above-described problems. Even when there is a variation in the shape of a workpiece, the control of a processing machine that can ensure proper processing efficiency while suppressing damage to the processing portion. An object of the present invention is to provide a control method for an apparatus and a processing machine.

The control device of the processing machine of the present invention is
The workpiece is machined according to the machining program, and the control value of the machining machine is varied by the override value, and the machining load value of the machining machine is controlled to be lower than the target load value that is the upper limit of the machining load value. In the control device of the processing machine,
A monitoring unit for acquiring the processing load value of the processing machine;
A first setting unit that changes the override value to an upper limit that is an upper limit of the override value according to the machining load value;
When the processing load value exceeds a processing threshold set for performing processing determination of the processing machine, the override value of the processing machine is changed to an initial override value smaller than the upper limit value, and the first setting unit And a determination unit to be set.

Moreover, the control device of the processing machine of the present invention is:
The workpiece is machined according to the machining program, and the control value of the machining machine is varied by the override value, and the machining load value of the machining machine is controlled to be lower than the target load value that is the upper limit of the machining load value. In the control device of the processing machine,
When the workpiece has a plurality of machining points,
A monitoring unit for acquiring the processing load value of the processing machine;
A first setting unit that changes the override value to an upper limit that is an upper limit of the override value according to the machining load value;
A second setting unit that sets, in the first setting unit, a temporary upper limit value such that the maximum load value of the machining load value becomes the target load value for each machining location of the workpiece; Is.

The control method of the processing machine of the present invention is
The workpiece is machined according to the machining program, and the control value of the machining machine is varied by the override value, and the machining load value of the machining machine is controlled to be lower than the target load value that is the upper limit of the machining load value. In the control method of the processing machine,
The override value is changed to an upper limit value that is an upper limit of the override value according to the machining load value,
When the processing load value exceeds a processing threshold set for performing processing determination of the processing machine, the override value of the processing machine is changed to an initial override value smaller than the upper limit value and controlled. .

The control method of the processing machine of the present invention is
The workpiece is machined according to the machining program, and the control value of the machining machine is varied by the override value, and the machining load value of the machining machine is controlled to be lower than the target load value that is the upper limit of the machining load value. In the control method of the processing machine,
When the workpiece has a plurality of machining points,
The override value is changed to an upper limit value that is an upper limit of the override value according to the machining load value,
For each machining location of the workpiece, a temporary upper limit value such that the maximum load value of the machining load value becomes the target load value is controlled as the upper limit value.

According to the processing machine control device configured as described above and the processing machine control method performed as described above according to the present invention,
Even if there are variations in the shape of the workpiece, it is possible to perform machining load control that can ensure proper machining efficiency while suppressing breakage of the machining portion.

It is a figure which shows the structure of the processing machine of Embodiment 1 of this invention, and the control apparatus of a processing machine. It is the flowchart which showed the process load control of the control apparatus shown in FIG. It is the flowchart which showed the control of the process determination in the process load control shown in FIG. FIG. 3 is a flowchart showing control for setting an override value in the machining load control shown in FIG. 2. FIG. It is a flowchart for demonstrating control of the processing machine shown in FIG. 1, and the control apparatus of a processing machine. 6 is a flowchart showing control for setting a temporary upper limit value shown in FIG. 5. 6 is a flowchart showing control for setting a temporary upper limit value shown in FIG. 5. 6 is a flowchart showing control for correcting the machining program shown in FIG. 5. It is a flowchart for demonstrating control of the control apparatus of the processing machine shown in FIG. It is a figure for demonstrating the structure of the workpiece | work which processes using the processing machine shown in FIG. It is the figure which showed the processing program for demonstrating the change of the processing program in the control apparatus of the processing machine shown in FIG. It is the figure which showed the processing program for demonstrating the change of the processing program in the control apparatus of the processing machine shown in FIG. It is the figure which showed the processing program for demonstrating the change of the processing program in the control apparatus of the processing machine shown in FIG. It is the figure which showed the processing program for demonstrating the change of the processing program in the control apparatus of the processing machine shown in FIG. It is the figure which showed the processing program for demonstrating the change of the processing program in the control apparatus of the processing machine shown in FIG. It is a figure for demonstrating transition of the processing load value and feed rate in the movement of a X-axis direction at the time of processing by each processing program of FIG. It is a figure for demonstrating the transition of the machining load value in the movement of an X-axis direction, and a feed rate when each machining program of FIG. 12 introduces the conventional machining load control, and is machined. FIG. 13 is a diagram for explaining a transition of a machining load value and a feed rate in movement in the X-axis direction when machining is performed with each machining program of FIG. 12 and machining load control according to the first embodiment is introduced. It is a figure for demonstrating the transition of the machining load value in the movement of an X-axis direction, and a feed rate when each machining program of FIG. 15 introduces the machining load control of Embodiment 1, and is machined. It is a figure which shows the structure of the processing machine of Embodiment 2 of this invention, and the control apparatus of a processing machine. It is a figure which shows the structure of the processing machine of Embodiment 3 of this invention, and the control apparatus of a processing machine. It is the flowchart which showed the process load control of the control apparatus shown in FIG.

Embodiment 1 FIG.
Embodiments of the present invention will be described below. FIG. 1 is a diagram showing a configuration of a processing machine and a control device for the processing machine according to Embodiment 1 of the present invention. FIG. 2 is a flowchart showing machining load control of the control device shown in FIG. FIG. 3 is a flowchart showing machining determination control in the machining load control shown in FIG. FIG. 4 is a flowchart showing control for setting an override value in the machining load control shown in FIG. FIG. 5 is a flowchart for explaining the control of the processing machine and the control device for the processing machine shown in FIG.

  6 and 7 are flowcharts showing control of setting the temporary upper limit value shown in FIG. FIG. 8 is a flowchart showing control for correcting the machining program shown in FIG. FIG. 9 is a flowchart for explaining control of the control device for the processing machine shown in FIG. FIG. 10 is a diagram for explaining the configuration of a workpiece to be processed using the processing machine shown in FIG. 10A is a top view of the workpiece, FIG. 10B is a side view of the workpiece, and FIG. 10C is a diagram showing the position of the workpiece in the X-axis direction.

  11 to 15 are diagrams showing machining programs for explaining changes in the machining program in the control device for the machining machine shown in FIG. FIGS. 16 to 19 are diagrams for explaining the transition of the machining load value and the feed rate in the movement in the X-axis direction when machining is performed by each machining program. FIG. 16 is a diagram when machining is performed by the machining program of FIG. FIG. 17 is a diagram when machining is performed by the machining program of FIG. FIG. 18 is a diagram when machining is performed by the machining program of FIG. FIG. 19 is a diagram when machining is performed by the machining program of FIG.

  In FIG. 1, a control device 10 is a part of an NC (abbreviation of numerical control, hereinafter abbreviated as NC) device 120 for controlling a processing machine 100 such as a machining center based on a machining program, or an NC It is configured as an auxiliary device for the device 120. The processing machine 100 fixes and processes a workpiece 107 on a table 108. Further, the processing machine 100 performs cutting by rotating a rotary tool 106 on a main shaft 105 via a main shaft motor 101. The rotary tool 106 is a processing unit that processes the workpiece 107 of the processing machine 100, and is configured by a milling cutter or an end mill.

  The table 108 is configured to be movable in the axial direction of the main shaft 105 (hereinafter referred to as the Z-axis direction) by the Z-axis motor 102 via a ball screw, a linear guide, or the like. The main shaft 105 is configured to be freely movable in the X-axis direction and the Y-axis direction by the X-axis motor 103 and the Y-axis motor 104 via a ball screw, a linear guide, or the like. The X-axis, Y-axis, and Z-axis are orthogonal to each other, and the relative position and relative speed between the rotary tool 106 and the workpiece 107 are controlled using the Z-axis motor 102, the X-axis motor 103, and the Y-axis motor 104. 107 can be processed into an arbitrary shape. The table 108, the X-axis motor 103, the Y-axis motor 104, and the Z-axis motor 102 are moving units that move the workpiece 107.

  The main shaft motor 101, the Z-axis motor 102, the X-axis motor 103, and the Y-axis motor 104 are constituted by servo motors, for example. The spindle motor 101, the Z-axis motor 102, the X-axis motor 103, and the Y-axis motor 104 are respectively a spindle servo amplifier (hereinafter abbreviated as an amplifier) 111 and a Z axis based on commands from the NC device 120. Control is performed by the amplifier 112, the X-axis amplifier 113, and the Y-axis amplifier 114. Therefore, the main shaft motor 101 is a main drive unit, and the Z-axis motor 102, the X-axis motor 103, and the Y-axis motor 104 are movement drive units.

  The control device 10 includes a monitoring unit 1, a determination unit 2, a first setting unit 3, a first storage unit 4, an integration unit 5, a second setting unit 6, a second storage unit 7, and a correction unit 8. . The monitoring unit 1 obtains information on the machining load value NP that is the load on the spindle 105 such as the power and current of the spindle motor 101 from the spindle amplifier 111 and monitors it as the current machining load value NP. The first storage unit 4 stores each parameter (including initial values).

  The determination unit 2 compares the current processing load value NP output from the monitoring unit 1 with the processing threshold value PT, and performs processing determination. If the determination unit 2 determines that processing is in progress, the determination unit 2 changes the override value OR (details will be described later) to an initial override value F-OR that is smaller than the upper limit value OR-OL of the override value OR. The first setting unit 3 can change the feed speed as the control value of the processing machine 100 set in the processing program from the result of the processing determination of the determination unit 2 (this is referred to as an override value OR). Is changed to the upper limit value OR-OL of the override value OR. The first setting unit 3 is set with the initial override value F-OR set by the determination unit 2. The integration unit 5 acquires processing data of the processing machine 100. The second storage unit 7 stores the machining data and the machining program acquired by the integration unit 5.

  The second setting unit 6 compares the machining data in the second storage unit 7 with each parameter in the first storage unit 4 and sets a temporary upper limit value K-OR-OL. The correction unit 8 receives the result of the second setting unit 6 and corrects each value and machining program. Each parameter and each value will be described in the description of control described later.

  Next, a control method of the processing machine control apparatus according to the first embodiment configured as described above will be described. In addition, about the control method of the control apparatus of a processing machine, the flow of each control is demonstrated first. Then, the flow of each control is demonstrated using the example of a specific machining program and a workpiece | work so that the effect may become clear.

First, machining load control performed in the control device 10 of the first embodiment will be described with reference to FIG. First, each value used in the following control will be described.
◎ "Override value OR of feed speed" (hereinafter simply referred to as override value OR)
This value indicates how much the feed rate is changed. The override value OR is set by “setting of the override value OR” described later. When the command value of the feed rate in the machining program is multiplied by the override value OR, the actual feed rate is obtained.

◎ "Override value upper limit value OR-OL" (hereinafter referred to as upper limit value OR-OL)
The override value OR is set by “setting of the override value OR” in FIG. 4. However, since the machining load control controls the feed rate after the machining load value is detected, the impact at the time of contact between the workpiece 107 and the rotary tool 106 is reduced. Tends to grow. Therefore, an upper limit value OR-OL is provided for the override value OR to prevent the feed speed from becoming excessively large.

◎ "Temporary override upper limit value K-OR-OL" (hereinafter referred to as temporary upper limit value K-OR-OL) The upper limit value OR-OL is stored in the first storage unit 4 and there is only one value. do not do. Therefore, a provisional upper limit value K-OR-OL is provided, and an arbitrary value can be set in the machining program.

  Processing load control will be described. First, when there is a machining load control start command, machining load control is started (step S101 in FIG. 2). Specifically, the machining load control start command method is described, for example, by describing a start command in a machining program and reading the command. Next, “override value OR”, “upper limit value OR-OL”, and “temporary upper limit value K-OR-OL” are respectively initialized (step S102 in FIG. 2). The initial value of the override value OR is 100%, the initial value of the upper limit value OR-OL is 150%, the initial value of the temporary upper limit value K-OR-OL is 0 (the temporary upper limit value K-OR-OL is not used) Is set as).

  Next, it is confirmed whether or not there is a use end command for the temporary upper limit value K-OR-OL in the machining program (step S103 in FIG. 2). Then, when there is a use end command for the temporary upper limit value K-OR-OL (YES), the temporary upper limit value K-OR-OL is overwritten with the initial value 0 (step S104 in FIG. 2). Further, when there is no use end command for the temporary upper limit value K-OR-OL (NO), it is confirmed whether or not the temporary upper limit value K-OR-OL is the initial value 0 (step S105 in FIG. 2). . When the temporary upper limit value K-OR-OL is not the initial value 0 (NO), the temporary upper limit value K-OR-OL is set as the upper limit value OR-OL (step S106 in FIG. 2). ).

  If the temporary upper limit value K-OR-OL is the initial value 0 (YES), the upper limit value OR-OL is set to the initial value (step S107 in FIG. 2). Next, it is confirmed whether or not there is a machining load control end command (step S108 in FIG. 2). If there is an end command (YES), the machining load control is ended (step S109 in FIG. 2). If there is no end command (NO), “machining determination” is performed (step S110 in FIG. 2).

  Next, “setting of an override value OR” is performed (step S111 in FIG. 2). Note that “processing determination” and “override value OR setting” will be described later. Next, the override value OR is output to the NC device 120 (step S112 in FIG. 2). Next, it returns to step S103 again and repeats the control shown above.

  In this way, by setting the temporary upper limit value K-OR-OL, the upper limit value OR-OL of the override value OR at a high risk location is low and the override value OR at a low risk location is set in the machining program. The upper limit value OR-OL of can be set high. As a result, the machining efficiency can be increased while ensuring the tool life. This effect is considered to be clear in the specific examples described later.

Next, the processing determination control shown in FIG. 2 will be described based on the flowchart of FIG. First, each value used in the following control will be described.
◎ "Machining load value NP"
This is the value of the processing load when the processing machine 100 performs processing.
◎ "Threshold PT for determining that it is in a machining state" (hereinafter referred to as machining threshold PT)
When the machining load value NP exceeds a certain value (machining threshold PT), it is for determining that “machining”. Therefore, although it is set as appropriate depending on the detection accuracy of the machining load value NP, for example, 1 to 10% of the maximum value of the machining load value NP, and when the current machining load value NP does not exceed the machining threshold PT, It is set so that “not being processed” is determined, and if exceeding, “not being processed” is determined.

◎ "Control timer CT"
After the machining load control is started, the machining load value NP is turned ON when the machining threshold value PT exceeds the machining threshold PT (determined to be “being machined”). Further, it becomes 0 when the machining load value NP is equal to or less than the machining threshold PT and a certain time (reset time RCT) elapses.
◎ "Reset time RCT"
As described above, the time for resetting the control timer CT is set.

"Processing initial override value F-OR" (hereinafter referred to as initial override value F-OR, however, it is different from the initial value of override value OR)
When the machining load value NP is equal to or greater than the machining threshold PT and the control timer CT is turned on, the override value OR is forcibly changed without going through “setting of the override value OR”. Further, it is set to a value smaller than the upper limit value OR-OL.

  Processing control performed by the determination unit 2 will be described. First, when processing load control is started, processing determination is started (step S201 in FIG. 3). Next, the current machining load value NP is read from the monitoring unit 1 (step S202 in FIG. 3). Next, it is determined whether or not the read current machining load value NP is equal to or greater than the machining threshold PT (step S203 in FIG. 3). When it is determined that “processing” is in progress (YES), it is compared whether or not the control timer CT is 0 (step S204 in FIG. 3).

  If the control timer CT is not 0 (NO), the process determination process is terminated (step S209 in FIG. 3). If the control timer CT is 0 (YES), the override value OR is changed to a preset initial override value F-OR (step S205 in FIG. 3). The initial override value F-OR is, for example, 100%. Next, the control timer CT starts counting (ON) (step S206 in FIG. 3).

  If it is determined in step S203 that “Non-machining” (NO), whether or not the value of the control timer CT is greater than the “reset time RCT” of the first storage unit 4 set in advance. Is confirmed (step S207 in FIG. 3). If the value of the control timer CT is equal to or longer than the reset time RCT (YES), the control timer CT is initialized to 0 (step S208 in FIG. 3). If the value of the control timer CT is smaller than the reset time RCT (YES), the processing determination process is terminated (step S209 in FIG. 3).

  By performing such machining determination control, the override value OR is forcibly set to the initial override value F-OR when switching from “Non-machining” to “Machining” (control from step S204 to step S205). You can switch to By this control, it is possible to prevent the control from being in time and to prevent the machining load from rapidly increasing, and to reduce the breakage of the machining part. In addition to the above, as a method of ending the processing determination, a method of resetting when a state where the processing load value NP is equal to or less than the processing threshold PT passes for a certain time is also conceivable.

Next, the override value setting control shown in FIG. 2 will be described with reference to the flowchart of FIG. First, each value used in the following control will be described.
◎ “Override value of feed speed OR”
This value indicates how much the feed rate is changed. This is the ratio between the current machining load value NP and the target load value TP. For example, if the current machining load value NP is 50 and the target load value TP is 100, the override value OR is 100 ÷ 50 = 2 (200%). Then, the override value OR changes as the machining load value NP changes. The actual feed speed is obtained by multiplying the command value of the feed speed in the program by the override value OR.

“Previous Override Value OR-1” (hereinafter referred to as Previous Override Value OR-1)
This is the value of the previous override value OR for which the override value OR is calculated. It is used as a variable for temporary storage during the calculation process of the override value OR.
◎ "Override value upper limit change amount OR-DOL" (hereinafter referred to as change amount upper limit value OR-DOL)
This is the upper limit value of the change amount of the override value OR.
◎ "Upper limit OR-OL"
This is the upper limit value of the override value OR.

  Control of setting of the override value OR performed in the first setting unit 3 will be described. First, the calculation process of the override value OR starts (step S301 in FIG. 4). Next, it is confirmed whether or not the override value OR has been changed to the initial override value F-OR in the last machining determination (step S311 in FIG. 4). If it is changed (YES), the override value OR is set as the initial override value F-OR (step S312 in FIG. 4), and the “override value setting” process is terminated (step S310 in FIG. 4). If not changed (NO), the current override value OR is set as the previous override value OR-1 (step S302 in FIG. 4). Next, the current machining load value NP is read (step S303 in FIG. 4). Next, the read current machining load value NP and the target load value TP are compared, and the ratio is set as the override value OR (step S304 in FIG. 4). For example, when the current machining load value NP is 50 and the target load value TP is 100, the override value OR is 200%. If the current machining load value NP is 0, the override value OR is set to the upper limit value OR-OL.

  Next, it is confirmed whether or not the change amount of the override value OR is equal to or less than the upper limit change amount OR-DOL (step S305 in FIG. 4). Specifically, the difference between the previous override value OR-1 and the override value OR is obtained. And it is confirmed whether the absolute value of a difference is below the upper limit variation | change_quantity OR-DOL set beforehand. If it is equal to or greater than the upper limit change amount OR-DOL (NO), the change amount is changed to the upper limit change amount OR-DOL, and the override value OR is corrected (step S306 in FIG. 4).

  For example, when OR-1 = 100%, OR = 150%, and OR-DOL = 5%, the absolute value of the difference between OR-1 and OR is 50%. Next, when the absolute value of the difference between the previous override value OR-1 and the override value OR is compared with the upper limit change amount OR-DOL, the absolute difference between OR-1 and OR is greater than the upper limit change amount OR-DOL. Since the value is larger, the amount of change is OR-DOL = 5%, and OR = (OR-1) + (OR-DOL) = 100% + 5% = 105%. In addition, when OR is smaller than OR-1, it is calculated as OR = (OR-1)-(OR-DOL).

  If the upper limit change amount OR-DOL is less than or equal to (NO), it is confirmed whether or not the override value OR is less than or equal to a preset upper limit value OR-OL (step S307 in FIG. 4). If the override value OR is larger than the upper limit value OR-OL (NO), the override value OR is changed to the upper limit value OR-OL (step S308 in FIG. 4). For example, when OR = 155% and OR-OL = 150%, the override value OR is larger than the upper limit value OR-OL, so the override value OR is rewritten to the upper limit value OR-OL, and OR = OR-OL = 150% It becomes. Then, the “override value setting” process is terminated (step S310 in FIG. 4).

  By thus providing the upper limit change amount OR-DOL of the override value OR, it is possible to suppress a rapid change in the feed rate. For this reason, it is possible to avoid deterioration of the appearance of the machined surface due to a rapid change in the feed rate. Further, by providing the upper limit value OR-OL of the override value OR, it is possible to prevent the feed speed from becoming excessively high and the machining surface from being deteriorated or the tool from being damaged. In addition, when the override value OR becomes F-OR in the processing determination,

  Next, control of setting the temporary upper limit value K-OR-OL will be described with reference to FIG. First, when a machining start command is issued from the NC device 120 (step S401 in FIG. 5), a machining start command is input to the control device 10 (step S407 in FIG. 5). Next, the storage of the processing data in the processing of the processing machine 100 is started (step S407 in FIG. 5). Next, when a machining end command is issued from the NC device 120 (step S402 in FIG. 5), the control device 10 finishes saving the machining data (step S409 in FIG. 5).

  Next, when a command for reviewing the temporary upper limit value K-OR-OL is issued from the NC device 120 (step S403 in FIG. 5), the control device 10 inputs a command for reviewing the temporary upper limit value K-OR-OL (FIG. 5). 5 step S408). Next, “setting of temporary upper limit value” (step S410 in FIG. 5) is performed. Next, “program correction operation” (step S411 in FIG. 5) is performed. The “setting of the temporary upper limit value” and the “program correction operation” will be described later. Next, preparation for the next processing is completed (step S405 in FIG. 5).

  Each time processing is completed as described above, the temporary upper limit value K-OR-OL is reviewed. As a result, it is possible to reduce the tool breakage by reducing the upper limit of the feed rate where the machining load value NP is large due to fluctuations in workpiece variations, that is, where the machined part is easily damaged, and the machining load value NP is reduced. In small places, that is, places where the tool is difficult to break, the upper limit of the feed rate can be increased to increase the machining efficiency.

  In this example, the upper limit value K-OR-OL is reviewed every time one workpiece is machined. However, the present invention is not limited to this example. For example, N workpieces are machined, and an average of N machining data is obtained. The temporary upper limit value K-OR-OL may be reviewed using the value.

Next, control of setting the temporary upper limit value K-OR-OL shown in FIG. 5 will be described based on the flowcharts of FIGS. 6 and 7. First, each value used in the following control will be described.
◎ "Maximum load value KF (N)"
Divide the machining program into m pieces. The largest machining load value among the machining load values NP of the Nth program among the divided programs is set as the maximum load value KF (N).
◎ "Maximum override value K-OR (N)"
This is the value of the override value OR at the maximum load value KF (N).

◎ "Upper limit value K-OR-OL-OL of provisional upper limit value"
This is the upper limit value of the temporary upper limit value K-OR-OL.
◎ "Lower limit value of temporary upper limit value K-OR-OL-UL"
This is the lower limit value of the temporary upper limit value K-OR-OL.

  The setting control of the temporary upper limit value K-OR-OL performed by the second setting unit 6 will be described. First, the setting of the temporary upper limit value K-OR-OL is started (step S501 in FIG. 6). Next, the latest machining data and the machining program are read (step S502 in FIG. 6). Next, the machining program is divided according to the rules (step S503 in FIG. 6).

Here, the “rule” is, for example, as follows.
◎ Each machining location pinched at the start and end of machining load control ◎ Each machining location pinched at the start and end of machining load control and for each line

The following values are extracted from the machining data corresponding to the machining program divided by such “rules” (step S503 in FIG. 6).
If the number of divisions of the machining program is m, the following is obtained for each divided machining program N = 1 to m.
◎ Maximum load value: KF (N)
◎ Maximum override value: K-OR (N)

  Next, processing is performed in the N-th divided machining program (step S506 in FIG. 6). Next, it is determined whether or not the maximum load value KF (N) is smaller than the target load value TP (step S507 in FIG. 6). When it is determined that the value is small (YES), it is determined whether or not the maximum override value K-OR (N) at the maximum load value KF (N) is equal to the upper limit value OR-OL (FIG. 6 step S508). When it is determined that they are equal (YES), the temporary upper limit value K-OR-OL (N) is set as K-OR-OL (N) = TP ÷ KF (N) (step in FIG. 6). S509).

  Next, it is determined whether or not the temporary upper limit value K-OR-OL (N) is equal to or less than a preset “upper limit value K-OR-OL-OL” (step S510 in FIG. 6). When it is determined that the temporary upper limit value K-OR-OL is larger (NO), the temporary upper limit value K-OR-OL is set as the upper limit value K-OR-OL-OL of the temporary upper limit value. (Step S511 in FIG. 6). Next, the set temporary upper limit value K-OR-OL (N) is output to the correction unit 8 (step S512 in FIG. 6).

  In Step S507, when it is determined that the maximum load value KF (N) is larger than the target load value TP (NO), the temporary upper limit value K-OR-OL is set to K-OR-OL (N) = Set as TP ÷ KF (N) (step S516 in FIG. 7). Next, it is compared whether or not the temporary upper limit value K-OR-OL (N) is greater than or equal to a preset "lower limit value K-OR-OL-UL of the temporary upper limit value" (step S517 in FIG. 7). If it is determined that the temporary upper limit value K-OR-OL is smaller (NO), the temporary upper limit value K-OR-OL is set as the lower limit value K-OR-OL-UL of the temporary upper limit value. (Step S518 in FIG. 7).

  Next, the set temporary upper limit value K-OR-OL (N) is output to the correction unit 8 (step S519 in FIG. 6). Then, it is determined whether the number of divisions is N = m (step S513 in FIG. 6). If N = m is not satisfied, N = N + 1 is set (step S520 in FIG. 6). And it returns to step S507 and repeats the control shown above. If N = m, the setting of the temporary upper limit value K-OR-OL ends (step S514 in FIG. 6).

  As described above, by setting the upper limit value K-OR-OL-OL of the temporary upper limit value and the lower limit value K-OR-OL-UL of the temporary upper limit value to the temporary upper limit value K-OR-OL, the feed speed Can be prevented from becoming abnormally large, resulting in damage to the tool or poor machining accuracy, and a problem that the feed rate is abnormally small and machining does not end.

  Next, machining program modification control performed by the modification unit 8 will be described with reference to the flowchart of FIG. First, modification of the machining program is started (step S601 in FIG. 8). Next, the machining program is read (step S602 in FIG. 8). Next, the machining program is divided according to the rules (step S603 in FIG. 8). When the number of divisions is m, the following control is performed for N = 1 to m.

Here, the “rule” is, for example, as follows.
◎ Each machining location pinched at the start and end of machining load control ◎ Machining location pinched at the start and end of machining load control and for each line The division of this machining program is as above. Since it is the same as step S503 shown, the data can also be used.

  Next, N = 1 is set (step S604 in FIG. 8), and it is confirmed whether or not the temporary upper limit value K-OR-OL (N) corresponding to the divided machining location of the Nth machining program is output (FIG. 8). Step S605). If the corresponding temporary upper limit value K-OR-OL (N) exists (YES), whether or not there is a use start command and a use end command for the temporary upper limit value K-OR-OL in the machining program. Is confirmed (step S606 in FIG. 8). When there is a use start command and a use end command for the temporary upper limit value K-OR-OL (YES), the temporary upper limit value K-OR-OL in the machining program is changed to the above-mentioned control, “temporary upper limit value The temporary upper limit value K-OR-OL output in “Setting” is corrected (step S607 in FIG. 8).

  When there is no use start command and use end command for the temporary upper limit value K-OR-OL (NO), the use start command and use end command for the temporary upper limit value K-OR-OL are added to the machining program (FIG. 8 step S608). Then, it is determined whether the number of divisions is N = m (step S609 in FIG. 8). If N = m is not satisfied, N = N + 1 is set (step S610 in FIG. 8). And it returns to step S605 and repeats the control shown above. If N = m, the modification of the machining program is terminated (step S611 in FIG. 8).

  In the case where there is no temporary upper limit value K-OR-OL, an example is shown in which the temporary upper limit value K-OR-OL is inserted into each divided part of the machining program. However, the present invention is not limited to this example. There may be a case where the upper limit value OR-OL is desired to be used without using the temporary upper limit value K-OR-OL as the value OR-OL. In that case, a command to use the upper limit value OR-OL without using the temporary upper limit value K-OR-OL is created. When there is the command, the temporary upper limit value K-OR- is used as the upper limit value OR-OL. The upper limit value OR-OL may be used without using OL.

  Next, introduction of machining load control in the first embodiment will be described. First, the machining program is corrected, and a machining load control command is added to the machining program (step S801 in FIG. 9). Next, parameters for machining load control are set (step S802 in FIG. 9). Next, when a processing test is performed and it is confirmed that the processing can be performed without any problem, a life test is performed (step S803 in FIG. 9). Next, it is confirmed whether or not the tool life is appropriate (step S804 in FIG. 9).

  Even if the machining time is shortened, the tool life will be extremely short, and the tool cost and labor cost for tool replacement may be higher than the machining cost. If (NO), the process returns to step S802, parameters such as “upper limit value OR-OL” are reset, and the control described above is repeated. If it is determined that the tool life is reasonable (YES), a command for reviewing the temporary upper limit value K-OR-OL is added to the machining program for correction (step S806 in FIG. 9). This is the introduction flow, and the introduction of the machining load control is completed (step S807 in FIG. 9).

  The subsequent flow is automatically executed in the mass production process. First, N workpieces are machined based on the machining load control introduced by the previous machining test and life test (step S808 in FIG. 9). Next, a temporary upper limit value K-OR-OL is set based on the machining data obtained by machining N units (step S809 in FIG. 9). Next, a “temporary upper limit value K-OR-OL” suitable for the variation of N workpieces is set, and the temporary upper limit value K-OR-OL is added to the machining program (step S810 in FIG. 9). Next, the review of the temporary upper limit value K-OR-OL is completed (step S811 in FIG. 9), and the next N workpieces are processed (step S808 in FIG. 9), and the above-described control is repeated.

  Thus, since the temporary upper limit value K-OR-OL can be set according to the workpiece variation, the risk of tool breakage can be reduced, and the time until the introduction of machining load control can be shortened.

  Hereinafter, a specific example of the control described above will be described.

  A specific work in the control of the first embodiment described above will be described. First, a workpiece 107 to be processed here is shown in FIG. FIG. 10A is a top view of the workpiece 107. FIG. 10B is a side view of the workpiece 107. FIG. 10C shows the position of the workpiece 107 in the X-axis direction. As is apparent from the figure, the workpiece 107 has a machining location Q1, a machining location Q2, and a machining location Q3.

  In order to compare the relative sizes of each machining point Q1, machining point Q2, and machining point Q3, values for the X axis, Y axis, and Z axis directions are shown. However, the values shown in the respective directions of the X axis, the Y axis, and the Z axis of each machining point Q1, Q2, Q3 are for facilitating understanding of the first embodiment, and the actual workpiece 107 is shown. However, the exact position is not confirmed before processing. And while rotating the rotary tool 106, it moves to a X-axis direction, and each process location Q1, Q2, Q3 of the workpiece | work 107 is cut.

  11 to 15 show machining programs for the workpiece 107, which are sequentially corrected in the following description. 16 to 19 show states when the workpiece 107 is machined using each machining program. And (A) in each figure shows the shape of the workpiece | work 107. FIG. Moreover, (B) in each figure shows transition of the machining path (in the X-axis direction, the same applies below) and the machining load. Moreover, (C) in each figure shows transition of the process route and the feed rate.

  FIG. 11 shows a state before the machining load control of the machining program for machining the workpiece 107 is introduced. An example of the machining program shown in FIG. 11 will be described. First, there is a program name on the first line and a tool change command on the second line. “M06” is a tool change command, and “T001” is a tool number to be changed. When the tool change is completed, the workpiece 107 moves to the machining start position of the machining location Q1, and an instruction for high-speed movement to the coordinates (0, 0, 0) is given on the third line. “G0” represents high-speed movement, and “X0Y0Z0” represents the coordinates of the X-axis, Y-axis, and Z-axis.

  The fourth line is a tool rotation command. “S” represents a rotation command, and “1000” represents the number of rotations. The unit is rpm. When rotating at 1000 rpm, there is a movement command on the sixth line in order to cut the part of the machining part Q1. “G1” represents a movement command at an arbitrary speed. “X90” represents the coordinates of the movement destination. “F” is a command for the movement speed, and “500” represents the movement speed.

  In other words, the sixth line is a command to cut the portion of the processing portion Q1 at 500 mm / min. The unit is mm / min. When it moves to X90, the cutting of the processing point Q1 is finished. Next, in order to move to the cutting start position at the position of the machining location Q2, there is an instruction for high-speed movement to X120 on the eighth line. Next, when moving to X120, there is a movement command on the 10th line in order to cut the part of the processing part Q2. The 10th line is a command to cut the portion of the processing portion Q2 at 500 mm / min. When moving to X170, the machining of the machining location Q2 is completed.

  Next, in order to move to the cutting start position at the position of the machining location Q3, there is an instruction for high-speed movement to X195 on the 12th line. When moving to X195, there is a movement command on the 14th line in order to cut the portion of the processing location Q3. The 14th line is a command to cut the part Q3 at 500 mm / min.

  When the workpiece 107 is machined using the machining program shown in FIG. 11 without introducing the machining load control (no override value OR) in this way, the transition between the machining path and the machining load value (FIG. 16). (B)), machining is performed as shown in the transition of the machining route and the feed rate (FIG. 16C).

  As shown in FIG. 16, the rotary tool 106 moves at a feed speed F500 from X = 0 to 90 on the X axis. Next, it moves at feed speed F2500 until X = 90-120. Next, it moves at a feed speed F500 from X = 120 to 170. Next, the robot moves at a feed speed F2500 from X = 170 to 195. Next, it moves at feed speed F500 from X = 195 to 290. Such processing has low processing efficiency because the feed rate does not change regardless of the processing load.

  First, in order to eliminate this, the machining program is modified and a machining load control command is added (step S801 in FIG. 9). Specifically, a machining load control start command and a machining load control end command are added before and after the machining command. The upper limit value of the override value is set to 150%. As a result, the machining program of FIG. 11 is modified like the machining program shown in FIG. As in the conventional case, when the machining load control is simply introduced and the workpiece 107 is machined using the machining program of FIG. 12, the transition of the machining path and the machining load (FIG. 17B), Processing is performed as shown in the transition between the path and the feed rate (FIG. 17C).

  As shown in FIG. 17, on the X axis, the rotary tool 106 moves while increasing from a feed speed F500 to a feed speed upper limit value F750 from X = 0 to 90. Next, X = 90 to 120 moves at a feed speed F2500 (feed speed MAX, which is the upper limit value as a processing machine, and the same applies to the feed speed when machining is not performed in the following). Next, from X = 120 to 170, the feed moves from the feed speed F500 to the upper limit F750 of the feed speed.

  Next, the robot moves at a feed speed F2500 from X = 170 to 195. Next, from X = 195 to 290, the moving speed is increased from the feeding speed F500 to the upper limit F750 of the feeding speed. However, on the way, as shown in FIG. 17C, the machining load value NP exceeds the target load value TP. Therefore, at this point, the feed speed drops from F750, which is the upper limit value of the feed speed, to the feed speed F500.

  Then, processing is performed up to a predetermined time at a feed speed F500 (here, up to 240 on the X axis). Then, after a predetermined time has elapsed, until X = 290, the vehicle moves again from the feed speed F500 to the feed speed upper limit value F750. When such machining load control is performed, as shown in FIG. 17B, when the machining load value NP exceeds the target load value TP, the feed rate of the rotary tool 106 is reduced and the rotary tool 106 may be damaged. Alternatively, although the rotating tool 106 is prevented from having a short life, the processing efficiency is lowered.

Therefore, in the first embodiment, the following control is performed.
Next, machining load control parameters (including initial values) are set (step S802 in FIG. 9). The parameters to be set are as follows and are set in the first storage unit 4.
◎ Initial value of override value OR (for example, 100%)
◎ Initial value of upper limit value OR-OL (for example, 150%)
◎ Initial value of provisional upper limit K-OR-OL (for example, 0 = OFF)
◎ Target load value TP
Processing threshold PT (for example, 1 to 10% of target load value TP)
Initial override value F-OR (for example, 100%, provided that it is different from the initial override value OR)
◎ Reset time RCT (for example, 3 seconds)
◎ Temporary upper limit upper limit value K-OR-OL-OL (for example, 500%)
◎ Lower limit value of temporary upper limit value K-OR-OL-UL (for example, 100%)
◎ Upper limit change amount OR-DOL (for example, 5%)
◎ Initial value of control timer CT (for example, 0)

  Next, a processing test is performed (step S803 in FIG. 9). FIG. 18 shows changes in machining path and machining load when machining the workpiece 107 by performing machining control in the first embodiment using the machining program in which machining load control in FIG. 12 is set ( FIG. 18 (B)) shows the transition of the machining route and the feed rate (FIG. 18 (C)).

  This will be described below with reference to FIGS. First, when the NC device 120 reads a machining load control start command on the fifth line of the machining program in FIG. 12, machining load control is started (step S101 in FIG. 2). Next, the override value OR, the upper limit value OR-OL, and the temporary upper limit value K-OR-OL are initialized, and 100%, 150%, OFF, and initial values are set (step S102 in FIG. 2). Next, processing begins. Specifically, this is the machining command on the sixth line in FIG. At this time, since the override value OR is 100% of the initial value, the feed speed at X = 0 is the same as the feed speed instruction value F500 on the sixth line in FIG. 12 of the machining program (FIG. 18).

  Next, it is confirmed whether or not there is a use end command for the temporary upper limit value K-OR-OL (step S103 in FIG. 2). Here, since there is no use end command for the temporary upper limit K-OR-OL before the sixth line in FIG. Next, it is confirmed whether or not the temporary upper limit value K-OR-OL is OFF (0) (step S105 in FIG. 2). Here, the provisional upper limit value K-OR-OL is OFF (the initial value is 0), so the answer is YES. Next, the upper limit value OR-OL is set to 150% of the initial value of the upper limit value OR-OL (step S107 in FIG. 2).

  Next, it is confirmed whether or not there is a machining load control end command (step S108 in FIG. 2). At this time, there is no processing load control end command before the sixth line in FIG. Next, processing determination is performed (step S110 of FIG. 2). Next, processing determination is started by the determination unit 2 (step S201 in FIG. 3). Next, the machining load value NP is input from the monitoring unit 1 (step S202 in FIG. 3). Next, it is confirmed whether or not the current machining load value NP is larger than the machining threshold value PT (step S203 in FIG. 3).

  As is apparent from FIG. 18B, the machining load value NP at the machining location Q1 of the workpiece 107 is smaller than the machining threshold value PT, and thus NO. Next, it is confirmed whether or not the control timer CT is larger than the reset time RCT (step S207 in FIG. 3). Here, since the control timer CT is in an OFF state, that is, the initial value is 0, it is NO. Then, the processing determination ends (step S209 in FIG. 3).

  Next, when the machining determination is finished, an override value OR is calculated (step S111 in FIG. 2). Next, the setting of the override value OR is started by the first setting unit 3 (step S301 in FIG. 4). Next, it is confirmed whether or not the override value OR has been changed to the initial override value F-OR in the last machining determination (step S311 in FIG. 4). Here, since no change has been made (NO), the current override value OR is stored as the previous override value OR-1 (step S302 in FIG. 4). Here, since the current override value OR is 100% of the initial value, it is stored as the previous override value OR-1 = 100%.

  Next, the current machining load value NP is acquired from the monitoring unit 1 (step S303 in FIG. 4). Here, as shown in FIG. 18C, the machining load value NP for X = 0 to 50 is zero. Therefore, 0 is acquired as the current machining load value NP. Next, the ratio between the current machining load value NP and the target load value TP is calculated (step S304 in FIG. 4). Here, since the current machining load value NP = 0, the override value OR = the upper limit value OR−OL (150%) is set.

  Next, it is confirmed whether or not the change amount (absolute value) of the override value OR from the previous override value OR-1 is equal to or less than the upper limit change amount OR-DOL (step S305 in FIG. 4). Here, since the previous override value OR-1 = 100% and the current override value OR = 150%, | OR-OR-1 | = 50%. Therefore, since | OR-OR-1 | is larger than the upper limit change value OR-DOL = 5%, it is NO.

  Next, the current override value OR = previous override value OR-1 + upper limit change value OR-DOL = 100% + 5% = 105% is set (step S306 in FIG. 4). Here, since the current override value OR is on the increase side with respect to the previous override value OR-1, an example in which the upper limit change value OR-DOL is added to the current override value OR is shown. It is set by subtracting the upper limit change value OR-DOL from the value OR.

  Next, it is confirmed whether or not the override value OR is equal to or lower than the upper limit value OR-OL (step S307 in FIG. 4). Here, since the override value OR = 105% and the upper limit value OR-OL = 150% or less, the answer is YES. Then, the calculation process of the override value OR is terminated (step S310 in FIG. 4). Next, it outputs to NC device 120 that it is override value OR = 105% (Step S112 of FIG. 2). Accordingly, since the override value OR is set to 105%, the feed speed F525 of the override value OR 105% is processed with respect to the command value of the feed speed F500 on the sixth line in FIG.

  Then, the control in steps S103 to S112 described above is repeated until there is a machining load control end command. Therefore, as indicated by X = 0 to 50 in FIG. 18C, the feed speed gradually increases between X = 0 and 50, and the feed is reached when the override value OR = the upper limit value OR−OL. It becomes constant at the speed F750. Further, even between X = 50 to 90 in FIG. 18C, the machining load value NP is equal to or less than the machining threshold PT, and the ratio between the target load value TP and the machining load value NP is 150% or more. The feed speed is maintained at F750. Next, since there is a load machining control end command on the seventh line in FIG. 12 (step S108 in FIG. 2), the machining load control is ended (step S109 in FIG. 2).

  Next, the ninth to eleventh lines of the machining program of FIG. 12 are basically the same as the fifth to seventh lines of FIG. Here, since the processing determination processing is different, processing different from the processing described above will be described below. As shown in FIG. 18B, when X = 125, the rotary tool 106 comes into contact with the machining location Q2 of the workpiece 107, and the machining load value NP becomes equal to or greater than the machining threshold PT (step S203 in FIG. 3). Next, it is confirmed whether or not the control timer CT is 0 (step S204 in FIG. 3). Here, since the control timer CT is in an OFF state, that is, 0, it becomes YES.

  Next, the override value OR is changed to the initial override value F-OR (100%) (step S205 in FIG. 3). Next, the control timer CT is turned on (step S206 in FIG. 3). Then, the processing determination ends (step S209 in FIG. 3). Next, the override value OR is calculated (step S111 in FIG. 2). Next, the setting of the override value OR is started by the first setting unit 3 (step S301 in FIG. 4). Next, it is confirmed whether or not the override value OR has been changed to the initial override value F-OR in the last machining determination (step S311 in FIG. 4). Here, since the override value OR is changed to the initial override value F-OR in the previous machining determination (YES), the override value OR is set as the initial override value F-OR (step S312 in FIG. 4). The “setting” process is terminated (step S310 in FIG. 4). As described above, when it is determined that machining is in progress, the override value OR is forcibly rewritten to the initial override value F-OR (100%). Therefore, at X = 125, the feed speed is reduced to F500, which is almost 100%.

  Thereafter, since the machining load value NP is equal to or less than the target load value TP and the ratio of the target load value TP to the machining load value NP is three times or more, OR-OL = 150% or more, and the feed rate is as shown above. As with the control described above, the value increases up to F750 and becomes constant. And between X = 165-170, the machining load value NP is zero with no load. Next, when moving to X = 165, the control timer CT is 3.2 seconds (= (165−125) ÷ 750 × 60) and the reset time RCT = 3 seconds or more in step S207 of FIG. (Step S204 in FIG. 3), the control timer CT is turned off (CT = 0).

  Then, since there is a machining load control end command on the eleventh line in FIG. 12 (step S108 in FIG. 2), the machining load control is terminated (step S109 in FIG. 2). The 13th to 15th lines in the machining program of FIG. 12 are basically the same as the 9th to 11th lines of FIG. However, since the machining load value NP is different, only the final feed speed is different. The machining test is performed as described above. If there is no problem, the life test is performed (step S803 in FIG. 9).

  Next, a life test is performed to determine whether it is appropriate (step S804 in FIG. 9). If the tool life is obtained as appropriate (YES), a command for reviewing the temporary upper limit value K-OR-OL is added to the machining program (step S806 in FIG. 9). Specifically, in the machining program of FIG. 12, the machining program is corrected by adding the Z-th line shown in FIG. Then, the introduction of machining load control is completed (step S807 in FIG. 9).

  Then, actual machining is performed with the machining program modified as shown in FIG. When the processing is started (steps S401 and S406 in FIG. 5), the storage of the processing data is started (step S407 in FIG. 5). Next, when the processing is completed (step S402 in FIG. 5), the storage of the processing data is ended (step S409 in FIG. 5). Next, after finishing the processing (step S808 in FIG. 9), a command for reviewing the temporary upper limit value K-OR-OL added to the Z-th line of the processing program shown in FIG. 13 (steps S403 and step in FIG. 5). By “S408),“ setting of temporary upper limit value K-OR-OL ”is executed (step S410 in FIG. 5).

  When the setting of the temporary upper limit value K-OR-OL is started (step S501 in FIG. 6), the latest machining data and its machining program are called (step S502 in FIG. 6). Next, the machining program is divided according to the rules. In the case of the machining program of FIG. 1-No. It is divided into three places like 3. The location to be machined by the machining program divided in this way is No. No. 1 is a location where the machining location Q1 of the workpiece 107 is processed. No. 2 is a location where the machining location Q2 of the workpiece 107 is machined. Reference numeral 3 denotes a portion where the machining portion Q3 of the workpiece 107 is processed.

  Then, the feeding speed F and the machining load value NP of each division location (No. 1 to No. 3) are analyzed, and the maximum value of the machining load value NP is determined for each division location (No. 1 to No. 3). The maximum load value KF (N) and the maximum override value K-OR (N) are set (N = 1 to 3). Next, N = 1 is set (step S506 in FIG. 6). Next, the maximum load value KF (1) of the first (No. 1) machining location obtained by dividing the machining program is compared with the target load value TP (step S507 in FIG. 6). Evidently from FIG.18 (C), since the maximum load value KF (1) of the process location Q1 of the workpiece | work 107 is smaller than the target load value TP, it is set to YES.

  Next, it is confirmed whether or not the maximum override value K-OR (1) is equal to the initial value OR-OL (step S508 in FIG. 6). Here, since the maximum override value K-OR (1) is 150%, it is equal to the upper limit value OR-OL, so it is YES. Next, the temporary upper limit value K-OR-OL (1) = TP ÷ KF (N) = 800% is calculated (step S509 in FIG. 6). Note that 800% indicates an estimated value because the target load value TP is about eight times the maximum load value KF (1) at the machining location Q1 of the workpiece 107 in FIG. 18B. is there.

  Next, it is confirmed whether or not the temporary upper limit value K-OR-OL (1) is equal to or lower than the upper limit value K-OR-OL-OL of the temporary upper limit value (step S510 in FIG. 6). Since the upper limit value K-OR-OL-OL of the temporary upper limit value is 500%, 800% of the temporary upper limit value K-OR-OL (1) is larger, so the result is NO. Next, the temporary upper limit value K-OR-OL (1) = the upper limit value K-OR-OL-OL = 500% of the temporary upper limit value is set (step S511 in FIG. 6). Next, the temporary upper limit value K-OR-OL (1) is output as 500% (step S512 in FIG. 6).

  Next, it is confirmed whether N = m (step S513 in FIG. 6). Since the program division number m is 3 and the current N is 1, it is NO. Next, N = N + 1 = 2 is set (step S520 in FIG. 6). Next, the maximum load value KF (2) of the second (No. 2) machining location obtained by dividing the machining program is compared with the target load value TP (step S507 in FIG. 6). Apparently from FIG. 18C, the maximum load value KF (2) is smaller than the target load value TP, and thus NO.

  Next, it is confirmed whether or not the maximum override value K-OR (2) is equal to the upper limit value OR-OL (step S508 in FIG. 6). Next, since the maximum override value K-OR (2) is 150%, it is equal to the upper limit value OR-OL, and therefore it becomes YES. Next, the temporary upper limit value K-OR-OL (2) = TP ÷ KF (N) = 300% is calculated (step S509 in FIG. 6). In FIG. 18B, 300% indicates an estimated value because the target load value TP is about three times the maximum load value KF (2) at the machining location Q2 of the workpiece 107. is there.

  Next, it is confirmed whether or not the temporary upper limit value K-OR-OL (2) is equal to or lower than the upper limit value K-OR-OL-OL of the temporary upper limit value (step S510 in FIG. 6). Since the upper limit value of the temporary upper limit value is 500% for K-OR-OL-OL, 300% of the temporary upper limit value K-OR-OL (2) is smaller, so the answer is YES. Next, the temporary upper limit value K-OR-OL (2) is output as 300% (step S512 in FIG. 6).

  Next, it is confirmed whether N = m (step S513 in FIG. 6). Since the program division number m is 3 and the current N is 2, the result is NO. Next, N = N + 1 = 3 is set (step S520 in FIG. 6). Next, the maximum load value KF (3) of the third (No. 3) machining location obtained by dividing the machining program is compared with the target load value TP (step S507 in FIG. 6).

  As is clear from FIG. 18C, the maximum load value KF (3) is larger than the target load value TP, and thus NO. Next, the temporary upper limit value K-OR-OL (3) = TP ÷ KF (N) = 60% is calculated (step S516 in FIG. 7). Note that 60% indicates an estimated value since the target load value TP is about 60% of the maximum load value KF (3) at the machining location Q3 of the workpiece 107 in FIG. 18B. is there.

  Next, it is confirmed whether or not the temporary upper limit value K-OR-OL (3) is greater than or equal to the lower limit value K-OR-OL-UL of the temporary upper limit value (step S517 in FIG. 7). Since the lower limit value K-OR-OL-UL of the temporary upper limit value is 100%, the temporary upper limit value K-OR-OL (3) is greater than or equal to the lower limit value K-OR-OL-UL of the temporary upper limit value. Therefore, it becomes NO. Next, the temporary upper limit value K-OR-OL (3) is set as 100% of the lower limit value K-OR-OL-UL of the temporary upper limit value (step S518 in FIG. 6). Next, the temporary upper limit value K-OR-OL (3) is output as 100% (step S512 in FIG. 6). Next, it is confirmed whether N = m (step S513 in FIG. 6). Then, since the program division number m is 3 and the current N is 3, the “temporary upper limit value setting” is terminated (step S514 in FIG. 6).

  Next, when the “setting of the provisional upper limit value” is completed, the processing of “machining program correction work” is started (step S411 in FIG. 5). Next, the machining program correction work is started (step S601 in FIG. 8). Next, a machining program is called (step S602 in FIG. 8). The machining program called here is the machining program of FIG. 14 used for machining. Next, the called machining program is divided into m pieces (step S603 in FIG. 8). The method of dividing the machining program is the same as step S503 in FIG.

  Next, N = 1 is set (step S604 in FIG. 8). Next, it is confirmed whether the temporary upper limit value K-OR-OL (1) corresponding to the divided machining location of the first (No. 1) machining program is output from the second setting unit 6 (step S605 in FIG. 8). ). Next, since there is a corresponding temporary upper limit value K-OR-OL (1), it is confirmed whether there is a use start command and a use end command for the temporary upper limit value K-OR-OL in the machining program (FIG. 8 step S606). Here, since there is no use start command and use end command for the temporary upper limit value K-OR-OL in the machining program, the answer is NO.

  Next, in the machining program of FIG. 15, the temporary upper limit value K-OR-OL is added to the sixth line and the temporary upper limit value K-OR-OL is added to the sixth line, as shown in FIG. Is designated as 500. This value is the value K-OR-OL (1) calculated in “Setting the temporary upper limit value”. The above control is repeated from N = 1 to 3 to complete the machining program correction processing (step S611 in FIG. 8). Each command is added as shown in FIG.

  FIG. 19 shows a case where machining is performed using a machining program using the machining load control of FIG. Since there is an instruction to start using the temporary upper limit value K-OR-OL in the 6th, 12th, and 18th lines of the machining program of FIG. 15, step S103 is NO in the machining load control of FIG. YES, and the value of the temporary upper limit value K-OR-OL is set and used as the upper limit value OR-OL.

  Therefore, as shown in FIG. 19, the upper limit value OR-OL of the override value is 500% of the temporary upper limit value K-OR-OL at the machining location Q1 of the workpiece 107, 300% at the machining location Q2, and at the machining location Q3. 100%. Therefore, the feed speed is controlled to be F2500 at the machining location Q1 of the workpiece 107, F1500 at the machining location Q2 of the workpiece 107, and F500 at the machining location Q3 of the workpiece 107.

  Compared to FIG. 18 before the temporary upper limit value K-OR-OL is set as the upper limit value K-OR and FIG. 19 after the temporary upper limit value K-OR-OL is set as the upper limit value K-OR, The maximum load value at the time of X = 210 is smaller in the case shown in FIG. 19 than in the case of FIG. 18, and the machining efficiency is larger in the hatched portion shown in FIG. 19 than in the case shown in FIG. It has become.

  In this way, by setting the upper limit value OR-OL as appropriate using the temporary upper limit value K-OR-OL, the machining efficiency can be increased and the breakage of the tool can be suppressed. Further, since tool wear and breakage can be suppressed, machining accuracy can be ensured, and the number of tool replacements can be reduced, so that the maintenance time of the machine can be reduced, the machine operating rate can be improved, and labor costs can be further reduced. In addition, since it is not necessary to take into account variations between workpieces, the number of life tests is reduced, and the time until introduction of machining load control can be shortened.

  In the first embodiment, the processing machine having the three axes of the X axis, the Y axis, and the Z axis is shown as an example. However, the present invention is not limited to this, and the same can be applied to a processing machine having two or more axes. It is possible to achieve the same effect.

  Further, it is preferable that one target load value TP is set for one process, preferably one for a tool, and further, the target load value TP is set to a maximum value of the machining load value of the target process. In this way, by setting the target load value TP to one, the control can be simplified and the machining load control can be easily introduced.

  Further, by making the target load value TP the maximum value of the machining load value of the target process, the machining time shortening effect of the machining load control can be maximized. Further, as the processing data when setting the temporary upper limit value, “reference processing data” and “a plurality of processing data up to the latest process” may be compared.

  Moreover, in this Embodiment, although the 1st memory | storage part 4 and the 2nd memory | storage part 7 were provided, and the example which stores various information in each was shown, it comprises as one memory | storage part, without being restricted to this. In addition, the NC device 120 may be provided with a storage unit. Since this is the same in the following embodiments, the description thereof will be omitted as appropriate.

  According to the processing machine control device and the processing machine control method of the first embodiment configured as described above, when the processing load value exceeds the processing threshold value, the initial override value is changed. An increase in the machining load value can be prevented in advance, and the life of the machined part and machining efficiency can be improved.

  Moreover, since the first setting unit can return the initial override value to the upper limit value, the processing efficiency can be improved.

  Further, since the first setting unit maintains the initial override value unless the machining load value is lower than the target load value, the life of the rotary tool as the machining unit is further improved.

  Moreover, since the 2nd setting part sets a temporary upper limit as an upper limit for every process location of a workpiece | work, it can improve process efficiency further.

  Moreover, since the 2nd setting part has set the upper limit value of the temporary upper limit value and the lower limit value of the temporary upper limit value, excessive processing of the processing part is prevented, or processing efficiency is unnecessarily reduced. Can do.

  In addition, the correction unit can add the start of use of the temporary upper limit value and the end of use of the temporary upper limit value for each machining part of the workpiece of the machining program, so the machining program is automatically corrected and the temporary upper limit value is used. It becomes possible to control.

  In addition, since the processing load value is acquired from the main drive unit that drives the processing unit that processes the workpiece of the processing machine, simple processing control is possible.

  In the first embodiment, the example in which the monitoring unit 1 acquires the load value of the spindle motor 101 of the spindle 105 via the spindle amplifier 111 and the NC device 120 and sets it as the machining load value is shown. In addition to this, for example, the load value of the Z-axis motor 102 is the Z-axis amplifier 112, the load value of the X-axis motor 103 is the X-axis amplifier 113, and the load value of the Y-axis motor 104 is the Y-axis. Even if the signals acquired from the amplifier 114 and the signals of the motors 101, 102, 103, and 104 such as current and power consumption are set as the machining load values, the control can be performed in the same manner as in the first embodiment. .

  In this case, according to the control method of the processing machine, it is possible to reflect the back component force and the feed component force in the control in addition to the main component force acting on the main shaft. An increase in the back component force and feed component force causes inaccuracy such as chatter, tool and workpiece falling. Therefore, by detecting the back force and feed force and controlling the feed speed, it is possible to grasp and control the machining state in more detail, suppress chatter and tool or workpiece collapse, and improve accuracy. This can be further prevented.

  In the first embodiment, the feed rate is shown as an example of the control value of the processing machine. However, the present invention is not limited to this, and for example, the rotational speed of the processing portion of the processing machine is set as the control value. It is also possible.

Embodiment 2. FIG.
FIG. 20 is a diagram showing the configuration of the processing machine and the control device for the processing machine in the second embodiment of the present invention. In the figure, the same parts as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted. As shown in the figure, the processing load value of the monitoring unit 150 is acquired not from the main shaft amplifier 111 but from the clamp ammeter 201 arranged in the wiring unit such as the main shaft motor 101 or the main shaft servo. And the monitoring part 1 can acquire a process load value from the signal of this clamp ammeter 201, and can perform it similarly to the said Embodiment 1. FIG.

  According to the processing machine control device and the processing machine control method of the second embodiment configured as described above, the processing load value is acquired as well as the same effect as the first embodiment. Therefore, the control device can be installed easily and inexpensively.

Embodiment 3 FIG.
FIG. 21 is a diagram showing the configuration of the processing machine and the control device for the processing machine in the third embodiment of the present invention. In the figure, the same parts as those in the above embodiments are denoted by the same reference numerals, and description thereof is omitted. As shown in the figure, an input / output interface (hereinafter referred to as an input / output IF) 22 capable of executing instructions by accessing the correction unit 8, the first storage unit 4, the second storage unit 7, and the third storage unit 23 is provided. Prepare. The third storage unit 23 will be described later. By accessing the first storage unit 4, the second storage unit 7, and the third storage unit 23 from the input / output IF 22, the machining program can be easily corrected.

  Further, the temporary upper limit value K-OR-OL can be changed at an arbitrary timing because the correction unit 8 can be accessed from the input / output IF 22. Further, it is possible to modify the machining program that does not introduce machining load control in the NC device 120 from the input / output IF 22 to a machining program corresponding to machining load control from machining data. .

  A control method of the processing machine control apparatus of the third embodiment configured as described above will be described based on the flowchart of FIG. First, when the input / output IF 22 starts control of modification of the machining program (step S901 in FIG. 22), the machining program to be modified is selected (step S902 in FIG. 22), and the machining program is read from the second storage unit 7 (FIG. 22). 22 step S903).

  Next, machining data serving as a reference for the machining program is selected (step S904 in FIG. 22), and machining data is read from the second storage unit 7 (step S905 in FIG. 22). Next, a target tool to be introduced into the machining load control is designated (step S906 in FIG. 22). Next, a machining program and machining data corresponding to the selected target tool are extracted (step S907 in FIG. 22), and the maximum load value is set as the target load value TP (step S908 in FIG. 22). Instead of setting the maximum load value to the target load value TP, a value obtained by multiplying the maximum load value by a preset coefficient may be set as the target load value TP. Next, before and after the machining program, it is confirmed whether or not there is a machining load control start designation and termination command, and if there is no such program, it is added (step S909 in FIG. 22).

  In addition, when the machining program is corrected, an item to be excluded from the correction target can be set in the third storage unit 23. In this way, by registering items to be excluded from the correction target in the third storage unit 23, it is possible to exclude them from the correction of the machining load control. As an item to be excluded, for example, when the tool is a drill, if the feed is changed during the processing from the structure of the tool, the processing becomes unstable.

  According to the processing machine control device and the processing machine control method of the third embodiment configured as described above, the machining program for machining load control as well as the same effects as those of the above embodiments are provided. By correcting this, the time until the introduction of machining load control can be shortened.

  It should be noted that the present invention can be freely combined with each other within the scope of the invention, and each embodiment can be appropriately modified or omitted.

Claims (11)

The workpiece is machined according to the machining program, and the control value of the machining machine is varied by the override value, and the machining load value of the machining machine is controlled to be lower than the target load value that is the upper limit of the machining load value. In the control device of the processing machine,
A monitoring unit for acquiring the processing load value of the processing machine;
A first setting unit that changes the override value to an upper limit that is an upper limit of the override value according to the machining load value;
When the processing load value exceeds a processing threshold set for performing processing determination of the processing machine, the override value of the processing machine is changed to an initial override value smaller than the upper limit value, and the first setting unit A control device for a processing machine, comprising: 2. The processing machine control device according to claim 1, wherein the first setting unit returns the initial override value to the upper limit value in accordance with the processing load value of the processing machine after changing to the initial override value. 3. 3. The processing machine according to claim 2, wherein the first setting unit maintains the initial override value when the processing load value of the processing machine does not become lower than the target load value after changing to the initial override value. 4. Control device. The workpiece is machined according to the machining program, and the control value of the machining machine is varied by the override value, and the machining load value of the machining machine is controlled to be lower than the target load value that is the upper limit of the machining load value. In the control device of the processing machine,
When the workpiece has a plurality of machining points,
A monitoring unit for acquiring the processing load value of the processing machine;
A first setting unit that changes the override value to an upper limit that is an upper limit of the override value according to the machining load value;
A second setting unit that sets, in the first setting unit, a temporary upper limit value such that the maximum load value of the machining load value becomes the target load value for each machining location of the workpiece; Control device for processing machines. When the processing load value exceeds a processing threshold set for performing processing determination of the processing machine, the override value of the processing machine is changed to an initial override value smaller than the upper limit value, and the first setting unit The processing machine control device according to claim 4, further comprising: a determination unit that is set to The control device for a processing machine according to claim 4 or 5, wherein the second setting unit sets an upper limit value of the temporary upper limit value and a lower limit value of the temporary upper limit value. The correction part which adds the use start of the said temporary upper limit value, and the use end of the said temporary upper limit value for every said process location of the said workpiece | work of the said machining program is provided. Processing machine control device. The processing machine includes a processing unit that processes the workpiece, a moving unit that moves the workpiece, a main drive unit that drives the processing unit, and a movement drive unit that drives the moving unit. ,
8. The processing machine control device according to claim 1, wherein the monitoring unit acquires the processing load value from the main drive unit. 9. The processing machine includes a processing unit that processes the workpiece, a moving unit that moves the workpiece, a main drive unit that drives the processing unit, and a movement drive unit that drives the moving unit. ,
8. The processing machine control device according to claim 1, wherein the monitoring unit acquires the processing load value from the main driving unit and the movement driving unit. 9. The workpiece is machined according to the machining program, and the control value of the machining machine is varied by the override value, and the machining load value of the machining machine is controlled to be lower than the target load value that is the upper limit of the machining load value. In the control method of the processing machine,
The override value is changed to an upper limit value that is an upper limit of the override value according to the machining load value,
When the processing load value exceeds a processing threshold set for performing processing determination of the processing machine, the override value of the processing machine is changed to an initial override value smaller than the upper limit value and controlled. Control method. The workpiece is machined according to the machining program, and the control value of the machining machine is varied by the override value, and the machining load value of the machining machine is controlled to be lower than the target load value that is the upper limit of the machining load value. In the control method of the processing machine,
When the workpiece has a plurality of machining points,
The override value is changed to an upper limit value that is an upper limit of the override value according to the machining load value,
A processing machine control method for controlling, as the upper limit value, a temporary upper limit value at which a maximum load value of the machining load value becomes the target load value for each machining portion of the workpiece.

Images