WO2016038687A1

WO2016038687A1 - Numerical control apparatus

Info

Publication number: WO2016038687A1
Application number: PCT/JP2014/073811
Authority: WO
Inventors: 光雄渡邊; 正一嵯峨崎; 悠貴平田
Original assignee: 三菱電機株式会社
Priority date: 2014-09-09
Filing date: 2014-09-09
Publication date: 2016-03-17
Also published as: DE112014006864T5; CN106687874A; JPWO2016038687A1; CN106687874B; JP5823082B1; DE112014006864B4

Abstract

A numerical control apparatus for machining a target object to be machined by moving, and at the same time vibrating, a tool and the target object relative to each other along a movement path by means of a drive shaft provided to the tool or the target object, said numerical control apparatus being provided with: an analysis processing unit which reads both a feed rate of movement along the movement path and a clamp feed rate from a machining program; a feed-rate-with-vibration calculation unit which, on the basis of given vibratory cutting conditions, calculates a feed rate with vibration, which is a feed rate resulting from imparting vibration to the aforementioned read feed rate of movement; and a feed-rate-with-vibration clamping unit which, if the calculated feed rate with vibration exceeds the aforementioned read clamp feed rate, reduces the original feed rate without vibration so that the calculated feed rate with vibration is equal to or less than the clamp feed rate.

Description

Numerical controller

The present invention relates to a numerical control device that relatively moves and controls a workpiece and a tool for machining the workpiece.

Conventionally, in turning, a numerical control device having a cutting tool feed mechanism that feeds a cutting tool to a workpiece and a control mechanism that controls a cutting tool feed drive motor by vibrating the cutting tool at a low frequency is known. It has been proposed (see Patent Documents 1 to 3). In this numerical control apparatus, the control mechanism feeds the cutting tool in synchronization according to the operating means for performing various settings, and the workpiece rotation speed set by the operating means or the cutting tool feed amount per one cutting tool rotation. As data that can be operated at a low frequency of 25 Hz or more to be operated, at least the advance amount, the retract amount, the advance speed, and the retract speed of the cutting tool feed mechanism according to mechanical characteristics such as inertia of the feed shaft or motor characteristics are tabulated in advance. Vibration cutting information storage means and motor control means for controlling the cutting tool feed drive motor based on the data stored in the vibration cutting information storage means. Thereby, low frequency vibration is generated by repeating forward and backward movements along the interpolation path.

Japanese Patent No. 5033929 Japanese Patent No. 5139591 Japanese Patent No. 5139592

The above Patent Documents 1 to 3 show a method of driving a motor by generating a movement command in which vibration in the movement direction is superimposed on a movement command designated from a program. However, if vibration is superimposed on the movement command specified in the program, the movement command speed after vibration superimposition may be larger than the movement speed specified in the program, which is not expected by the machine operator There was a possibility that such a large speed was generated and a load was applied to the machine.

The present invention has been made in view of the above, and an object of the present invention is to obtain a numerical control device capable of controlling a moving speed superimposed with vibration during low frequency vibration cutting so as not to apply a load to the machine.

In order to solve the above-described problems and achieve the object, the present invention provides a tool or a workpiece to be driven along a movement path while relatively vibrating the tool and the workpiece by a drive shaft provided on the workpiece. A numerical control device that moves and processes the workpiece, an analysis processing unit that reads a feed speed and a clamp speed for moving the movement path from a machining program, and based on a given vibration cutting condition, A post-superimposition speed calculation unit that calculates a post-superimposition speed after the vibration is superimposed on the movement by the feed speed, and when the post-vibration superposition speed exceeds the clamp speed, the speed is less than the clamp speed. And a vibration speed clamp portion for reducing the feed speed.

The numerical control device according to the present invention has an effect that it is possible to control so that the moving speed on which vibration is superimposed during low frequency vibration cutting does not apply a load to the machine.

The block diagram which shows an example of a structure of the numerical control apparatus in

Embodiment

1 and 2 of this invention It is a figure which shows typically the structure of the axis | shaft of the numerical control apparatus in embodiment, Comprising: Fig.2 (a) is a figure in the case of moving only a tool to a Z-axis and an X-axis direction, FIG.2 (b) is FIG. Figure when moving the machining target in the Z-axis direction and moving the tool in the X-axis direction Diagram showing examples of vibration cutting conditions The figure which shows which amount each vibration cutting condition of Drawing 3 corresponds in the time change of the amount of movement. Diagram showing examples of vibration conditions The figure which shows the time change of the movement distance in feed speed [every minute] = 50 [mm / min]. The figure which shows the time change of the movement distance in feed speed [every minute] = 20 [mm / min]. The figure which shows a part of machining program concerning Embodiment 1 The figure which shows the movement path | route in the X-axis direction and Z-axis direction shown by the machining program of FIG. The figure which shows the vibration cutting conditions concerning Embodiment 1. FIG. Diagram showing the state of vibration cutting movement when the actual speed is not clamped The flowchart which shows the procedure which performs the clamp of real speed in

Embodiment

1 and 2 of this invention The figure which shows the mode of the vibration cutting movement at the time of clamping an actual speed in Embodiment 1. The figure which shows the vibration cutting conditions concerning Embodiment 2. FIG. Diagram showing the state of vibration cutting movement when the actual speed is not clamped The figure which shows the mode of the vibration cutting movement at the time of clamping an actual speed in Embodiment 2. The block diagram which shows an example of a structure of the numerical control apparatus in Embodiment 3 of this invention. The figure which shows a part of machining program concerning Embodiment 3 The figure which shows the example which sets a clamp speed for every drive axis as a parameter in Embodiment 3. The figure which shows the mode of vibration cutting movement when the speed of each drive shaft is not clamped The figure which shows the state of the vibration cutting movement when the speed of each drive shaft is not clamped according to the drive shaft The figure which shows the mode of the vibration cutting movement of the X-axis when the speed of each drive shaft is not clamped The figure which shows the mode of the vibration cutting movement of the Z-axis when the speed of each drive shaft is not clamped The flowchart which shows the procedure which performs the clamp of real speed in Embodiment 3. The figure which shows the mode of the vibration cutting movement at the time of clamping a real speed in Embodiment 3. The figure which shows the mode of the vibration cutting movement at the time of clamping an actual speed in Embodiment 3 according to X-axis Z-axis The figure which shows the mode of the vibration cutting movement of the X-axis at the time of clamping real speed in Embodiment 3. The figure which shows the mode of the vibration cutting movement of the Z axis at the time of clamping an actual speed in Embodiment 3.

Hereinafter, a numerical controller according to an embodiment of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to these embodiments.

Embodiment 1 FIG.
FIG. 1 is a block diagram of an example of the configuration of the numerical control device 1 according to the first embodiment. The numerical control device 1 includes a drive unit 10, an input operation unit 20, a display unit 30, and a control calculation unit 40.

The drive unit 10 is a mechanism that drives one or both of the machining target and the tool in at least two axial directions. The drive unit 10 is detected by a servo motor 11 that moves a workpiece or a tool in each axial direction defined on the numerical control device 1, a detector 12 that detects the position and speed of the servo motor 11, and the detector 12. And an X-axis servo control unit 13X and a Z-axis servo control unit 13Z for each axis direction for controlling the position and speed of the processing target or tool based on the position and speed. Hereinafter, when it is not necessary to distinguish the directions of the drive axes, the X-axis servo control unit 13X and the Z-axis servo control unit 13Z are simply referred to as the servo control unit 13. The numerical control apparatus 1 according to the first embodiment moves the tool and the machining target along the movement path with relative vibrations by using these drive shafts provided on the tool or the machining target. Processing.

Further, the drive unit 10 is based on the spindle motor 14 that rotates the spindle that holds the workpiece, the detector 15 that detects the position and rotation speed of the spindle motor 14, and the position and rotation speed detected by the detector 15. And a spindle control unit 16 for controlling the rotation of the spindle.

The input operation unit 20 is configured by an input means such as a keyboard, a button, or a mouse, and a user inputs a command to the numerical control device 1 or inputs a machining program or a parameter. The display unit 30 is configured by display means such as a liquid crystal display device, and displays information processed by the control calculation unit 40.

The control calculation unit 40 includes an input control unit 41, a data setting unit 42, a storage unit 43, a screen processing unit 44, an analysis processing unit 45, a machine control signal processing unit 46, and a PLC (Programmable Logic Controller) circuit. A unit 47, an interpolation processing unit 48, an acceleration / deceleration processing unit 49, and an axis data output unit 50.

The input control unit 41 receives information input from the input operation unit 20. The data setting unit 42 stores the information received by the input control unit 41 in the storage unit 43. As an example, when the input content is an edit of the machining program 432, the input control unit 41 reflects the edited content in the machining program 432 stored in the storage unit 43, and a parameter is input. Is stored in the storage area of the parameter 431 of the storage unit 43.

The storage unit 43 stores information such as the parameters 431 used in the processing of the control calculation unit 40, the machining program 432 to be executed, and the screen display data 433 to be displayed on the display unit 30. The storage unit 43 is provided with a shared area 434 for storing temporarily used data other than the parameters 431 and the machining program 432. The screen processing unit 44 performs control to display the screen display data 433 in the storage unit 43 on the display unit 30.

The analysis processing unit 45 reads the machining program 432 including one or more blocks, analyzes the read machining program for each block, reads the feed speed in the movement path direction, and generates a movement command for moving in one block. A command generation unit 451, and a vibration command analysis unit 452 that analyzes whether the machining program 432 includes a vibration command and generates a vibration condition included in the vibration command when the vibration command is included. . The vibration conditions generated by the vibration command analysis unit 452 include frequency and amplitude. The analysis processing unit 45 further includes an actual speed clamp command analysis unit 453 that reads the clamp speed after vibration superposition specified by the program command of the machining program 432 and writes the clamp speed to the shared area 434 of the storage unit 43.

The machine control signal processing unit 46 confirms that the auxiliary command is instructed when the analysis processing unit 45 reads an auxiliary command that is a command for operating a machine other than a command for operating the drive axis that is a numerical control axis. Notify the PLC circuit unit 47. When the PLC circuit unit 47 receives notification from the machine control signal processing unit 46 that an auxiliary command has been commanded, the PLC circuit unit 47 executes processing corresponding to the commanded auxiliary command.

The interpolation processing unit 48 uses the movement command analyzed by the analysis processing unit 45 to obtain a command movement amount that is a movement amount that moves at a specified feed speed during a processing cycle that is a control cycle of the numerical control device 1. A command movement amount calculation unit 481 to calculate, a vibration movement amount calculation unit 482 that calculates a vibration movement amount that is a movement amount during a processing cycle for vibrating a tool or a machining target, and a command movement amount per processing cycle A movement amount superimposing unit 483 that calculates a superimposed movement amount in which the vibration movement amount is superimposed, a post-vibration superimposing speed calculation unit 484 that calculates a speed after vibration superimposition, and an upper limit of the post-vibration superimposition speed that is a speed after vibration superimposition And a vibration speed clamp portion 485 that limits the feed speed so that the value does not exceed the clamp speed. The processing cycle is also called an interpolation cycle.

The acceleration / deceleration processing unit 49 converts the superimposed movement amount of each drive axis output from the interpolation processing unit 48 into a movement command per processing cycle that takes acceleration / deceleration into consideration according to a pre-specified acceleration / deceleration pattern. The axis data output unit 50 sends the movement command per processing cycle processed by the acceleration / deceleration processing unit 49 to the X-axis servo control unit 13X, the Z-axis servo control unit 13Z, and the spindle control unit 16 that control each drive axis. Output.

In order to perform the processing while vibrating the tool or the processing target, as described above, the processing target and the tool may be relatively moved when performing the processing. FIG. 2 is a diagram schematically showing the configuration of the shaft of the numerical control apparatus 1 according to Embodiment 1 that performs turning. In this figure, a Z axis and an X axis that are orthogonal to each other in the drawing are provided. FIG. 2A shows a case where the workpiece 61 is fixed and only the tool 62, which is a turning tool for performing turning, for example, is moved in the Z-axis direction and the X-axis direction. FIG. 2B shows a case where the workpiece 61 is moved in the Z-axis direction and the tool 62 is moved in the X-axis direction. In any of these cases, the processing described below can be performed by providing both or either of the servo motor 11 and the spindle motor 14 on either or both of the processing object 61 and the tool 62 that are to be moved. It becomes possible.

FIG. 3 is a diagram showing an example of vibration cutting conditions. “No.” which is the condition number, “vibration condition item” which is the name of the condition, “unit” which indicates the unit of the condition, “calculation method” which is the calculation method of the condition using other conditions, and the condition One line is composed of “explanation” which is the contents of the above.

Hereinafter, the conditions under which “Description” in FIG. 3 is blank will be described. For example, the “spindle rotation speed” in (1) is the rotation speed of the spindle that rotates the workpiece to be machined, the unit being [r / min], and the rotation speed r per minute. “Frequency” in (3) is the frequency of vibration in vibration cutting. “Amplitude” in (5) is the amplitude of vibration of vibration cutting. The “feed rate [per minute]” in (7) is a unit [mm / min] and a feed amount [mm] per minute. The unit “feed rate [per rotation]” in (8) is [mm / r], and is a feed amount [mm] per one rotation of the main shaft.

FIG. 4 is a graph of the change in the movement distance with time on the horizontal axis and the movement distance on the vertical axis. Which part of the change in the movement distance corresponds to each vibration cutting condition shown in FIG. FIG.

Here, a specific example of how the time change of the moving distance changes when the “feed rate [per minute]” and the “feed rate [per rotation]” change under the given vibration conditions. It explains using.

FIG. 5 is a diagram illustrating an example of vibration conditions. Under the vibration conditions of FIG. 5, the movement distance time when “feed rate [per minute]” = 50 [mm / min], that is, “feed rate [per rotation]” = 0.0125 [mm / r]. FIG. 6 shows the change. Under the vibration conditions of FIG. 5, the movement distance time when “feed rate [per minute]” = 20 [mm / min], that is, “feed rate [per rotation]” = 0.005 [mm / r]. FIG. 7 shows the change.

6 and 7 are compared with the forward speed in the vibration superposition movement shown in FIGS. 3 and 4 (16) and the reverse speed in the vibration superposition movement (17). It can be seen that the “reverse vibration superimposition speed” in FIG. 6 is reduced in FIG. 7 where the feed speed is lower than in FIG. That is, if the vibration condition does not change, when the feed rate is lowered, the “amplitude” in (5), the “forward vibration superposition speed” in (16), and the “reverse vibration superposition speed” in (17) also become the feed speed. Proportionally decreases. The numerical control apparatus 1 according to the first embodiment uses this fact.

FIG. 8 is a diagram showing a part of the machining program 432 according to the first embodiment. In the command “G0 X0.0 Z0.0” indicated by the sequence number “N1” of the machining program 432 in FIG. 8, the coordinates “X0.0 Z0.0” of the first position of the X axis and the Z axis are designated. A positioning command is issued. In the command “G165 P1 F200” indicated by the next sequence number “N2”, “G165 P1” indicates the start of the vibration cutting control mode, and “F200” indicates the actual speed at the clamp speed 200 [mm / min]. Instructed to clamp. This clamping speed is a speed limit for the combined speed obtained by combining the speeds in the X-axis direction and the Z-axis direction.

The command “G1 X10.0 Z20.0 F50” indicated by the next sequence number “N3” indicates that vibration cutting that moves to “X10.0 Z20.0” by linear interpolation is executed. Further, “F” and a numerical value subsequent thereto indicate a command feed speed that is a cutting feed amount per minute, and in this example “F50”, a command feed speed = 50 [mm / min]. This command feed speed is a feed speed obtained by combining the feed speeds in the X-axis direction and the Z-axis direction. The command “G165 P0” indicated by the last sequence number “N4” means the end of the vibration cutting control mode.

FIG. 9 shows movement paths in the X-axis direction and the Z-axis direction indicated by the machining program 432 in FIG. The right side of FIG. 9 also shows the X-axis feed speed and Z-axis feed speed obtained by disassembling the travel distance, travel time, and command feed speed = 50 [mm / min] in this case in the X-axis direction and Z-axis direction. .

FIG. 10 is a diagram showing vibration cutting conditions. The “spindle rotation speed” is not shown in FIG. 8, but is described before the description of FIG. 8 of the machining program 432, for example. As described above, “feed speed” is described in the command indicated by the sequence number “N3” in FIG. The “number of vibrations per rotation” is given as the parameter 431 in the storage unit 43, for example, but may be described in the machining program 432. In addition, the conditions of vibration “frequency”, vibration “amplitude feed ratio”, and vibration “waveform” are shown. The “waveform” of the vibration in the first embodiment is a triangular wave in which the forward and backward movements are equal in time. 10 is information obtained from either the machining program 432 or the parameter 431.

In the conditions of vibration cutting shown in FIG. 8 to FIG. 10, if the actual speed is not clamped, the state of vibration cutting movement will be shown, with the horizontal axis representing time, the vertical axis representing the movement distance in the X axis direction, and the Z axis. FIG. 11 shows an XZ combined moving distance that is a combined moving distance of directions. As shown in FIG. 11, “forward vibration superposition speed” in (16) of FIG. 3 is 350 [mm / min], and “reverse vibration superposition speed” in (17) of FIG. 3 is 250 [mm / min. Therefore, both of them exceed the clamping speed of 200 [mm / min]. Here, the clamp speed 200 [mm / min] is set to 350 [mm / min] of “forward vibration superposition speed” which is the larger value of “forward vibration superposition speed” and “reverse vibration superposition speed”. The divided value is shown in FIG. 11 as “clamp ratio” = 0.5714.

In the numerical control apparatus 1 according to the first embodiment, the actual speed is clamped, that is, the actual speed is suppressed according to the flowchart of FIG. First, the actual speed clamp command analysis unit 453 reads the clamp speed 200 [mm / min] after vibration superposition indicated by “F200” of the sequence number “N2” in FIG. 8 from the machining program 432 and writes it in the shared area 434. (Step S101). Next, the post-vibration speed calculation unit 484 calculates the post-vibration speed based on the machining program 432 of FIG. 8 and the vibration cutting conditions shown in FIG. 10 (step S102). The post-superimposition speed calculation unit 484 calculates, for example, both the “forward vibration superposition speed” in (16) of FIG. 3 and the “reverse vibration superposition speed” in (17) as the post-superimposition speed. The “forward vibration superimposition speed” and “reverse vibration superposition speed” are, for example, “feed speed [per minute]” (5) amplitude, (12) forward, which are the vibration cutting conditions shown in FIG. It is obtained using the hourly feed amount and (13) the reverse feed amount. More specifically, the post-vibration superimposition speed calculation unit 484 sets the speeds after the forward and backward movements due to the vibration are superimposed on the movement based on the feed rate, respectively, as “forward vibration superposition speed” and “reverse vibration superposition speed”. Asking.

Then, in step S103, the vibration speed clamp unit 485 determines whether the post-vibration speed exceeds the clamp speed written in the shared area 434. Specifically, the vibration speed clamp unit 485 determines whether or not the larger one of the “forward vibration superposition speed” and the “reverse vibration superposition speed” exceeds the clamp speed.

As described above, as a method of determining whether the larger one of the “forward vibration superposition speed” and the “reverse vibration superposition speed” exceeds the clamp speed, the vibration post-superimposition speed and the clamp speed are substantially determined. What is necessary is just to be able to compare. Therefore, instead of comparing speeds, it may be a comparison of movement amounts at a predetermined time.

If neither the “forward vibration superimposition speed” nor the “reverse vibration superposition speed” exceeds the clamp speed (step S103: No), the interpolation processing unit 48 does not clamp the “feed speed” and performs normal operation. Execute (Step S105).

When the larger one of the “forward vibration superposition speed” and the “reverse vibration superposition speed” exceeds the clamp speed (step S103: Yes), the vibration speed clamp unit 485 clamps the “feed speed” (step S104). That is, the vibration speed clamp unit 485 sets the value obtained by dividing the clamp speed by the larger of the “forward vibration superposition speed” and the “reverse vibration superposition speed” as the “clamp ratio”, and the “feed speed” is set to the “clamp ratio”. A value obtained by multiplying is set as a new “feed speed”. Specifically, the “feed speed” commanded by “F50” of the sequence number “N3” in FIG. 8 is replaced with a value obtained by multiplying “clamp ratio” = 0.5714 shown in FIG. The interpolation processing unit 48 performs subsequent calculations. The “clamp ratio” may be equal to or less than a value obtained by dividing the clamp speed by the larger of “forward vibration superposition speed” and “reverse vibration superposition speed”.

In step S104, as described above, when the “feed rate” is clamped, the vibration cutting movement is performed by combining the time on the horizontal axis and the movement distance in the X-axis direction and the movement distance in the Z-axis direction on the vertical axis. FIG. 13 shows the XZ composite movement distance that is the distance. As shown in FIG. 13, by clamping the “feed speed”, the combined speed obtained by combining the speed in the X-axis direction and the speed in the Z-axis direction is suppressed to a clamp speed or less. In the case of FIG. 13, “forward vibration superposition speed” matches the clamp speed 200 [mm / min] by the clamp of “feed speed”.

Embodiment 2. FIG.
A block diagram showing an example of the configuration of the numerical control device 1 according to the second embodiment is FIG. In the vibration cutting condition of the first embodiment, as shown in FIG. 10, the “waveform” of the vibration is a symmetrical triangular wave in which the forward and backward movements are equal in time. In the second embodiment, the vibration of FIG. As shown in the cutting conditions, the forward time ratio of (10) in FIG. 3 is 0.75, and the backward time ratio of (11) in FIG. Different. Other conditions are the same as in the first embodiment. That is, the machining program in FIG. 8 and the movement path diagram in FIG. 9 are similarly applied to the second embodiment.

Under such conditions of vibration cutting, if the actual speed is not clamped, the state of vibration cutting movement is expressed as follows: time on the horizontal axis, movement distance in the X-axis direction and movement distance in the Z-axis direction. FIG. 15 shows the XZ combined movement distance, which is a combined movement distance. As shown in FIG. 15, “forward vibration superposition speed” in (16) of FIG. 3 is 250 [mm / min], and “reverse vibration superposition speed” in (17) of FIG. 3 is 550 [mm / min. Therefore, both of them exceed the clamping speed of 200 [mm / min]. Here, the clamp speed 200 [mm / min] is set to 550 [mm / min] of “reverse vibration superposition speed” which is the larger value of “forward vibration superposition speed” and “reverse vibration superposition speed”. The divided value is shown in FIG. 15 as “clamp ratio” = 0.3636.

Also in the numerical controller 1 according to the second embodiment, the actual speed is clamped, that is, the actual speed is suppressed according to the flowchart of FIG. 12 as in the first embodiment. The difference from the first embodiment is that, in the second embodiment, the “reverse vibration superimposition speed” before clamping is larger than the “forward vibration superposition speed”, so the clamp speed is divided by the “reverse vibration superposition speed”. It is only the point which makes the obtained value the clamp ratio. Since other points are the same as those of the first embodiment, description thereof is omitted. The “clamp ratio” may be equal to or less than a value obtained by dividing the clamp speed by the “reverse vibration superimposition speed”.

The state of the vibration cutting movement when the “feed rate” is clamped as in step S104 is as follows. The horizontal axis represents time, the vertical axis represents the movement distance in the X-axis direction and the movement distance in the Z-axis direction. The XZ composite movement distance is as shown in FIG. As shown in FIG. 16, by clamping the “feed speed”, the combined speed obtained by combining the speeds in the X-axis direction and the Z-axis direction can be suppressed to a clamp speed or less. In the case of FIG. 16, the “reverse vibration superimposition speed” matches the clamp speed 200 [mm / min] by the clamp of “feed speed”.

Embodiment 3 FIG.
FIG. 17 is a block diagram showing an example of the configuration of the numerical controller 2 according to the third embodiment. In the first and second embodiments, the clamping speed is designated by the machining program 432, but in the third embodiment, the clamping speed is designated as the parameter 431. The numerical control device 2 includes a drive unit 10, an input operation unit 20, a display unit 30, and a control calculation unit 40.

17 differs from FIG. 1 in that a parameter 431 in the storage unit 43 includes an actual speed clamp 4311 that is an upper limit value of the speed of each axis, and the analysis processing unit 45 includes an actual speed clamp command analysis unit 453. Is an unnecessary point. However, when the designation of the clamp speed by the machining program 432 and the designation of the clamp speed by the parameter 431 are used together, the actual speed clamp command analysis unit 453 may be provided in the analysis processing unit 45. The functions of the other components having the same reference numerals are the same as those in FIG.

Hereinafter, the third embodiment will be described in detail focusing on operations different from the first and second embodiments.

FIG. 18 is a diagram illustrating a part of the machining program 432 according to the third embodiment. The command “G165 P1” indicated by the sequence number “N2” in the machining program 432 in FIG. 18 is different from the command “G165 P1 F200” indicated by the sequence number “N2” in the machining program 432 in FIG. Not done. The other description of FIG. 18 is the same as FIG.

Instead, in the third embodiment, as shown in FIG. 19, the clamp speed for each drive axis as the feed axis is set as the actual speed clamp 4311 in the parameter 431 of the storage unit 43. Specifically, the clamping speed of the X axis is 150 [mm / min], and the clamping speed of the Z axis is 250 [mm / min]. In other words, when the actual command speed of each drive axis that is obtained by distributing the vibration superposed speed to the programmed feed speed to each drive axis exceeds the set value set in the parameter 431, the actual command speed of each drive axis The vibration speed clamp unit 485 clamps the feed speed so that is less than or equal to the speed set in the parameter 431 of each drive shaft. In the third embodiment, the vibration cutting is performed under the vibration cutting conditions shown in FIG.

Under the conditions of the vibration cutting process shown in FIGS. 18 and 19, if the speed of each drive shaft is not clamped, the state of vibration cutting movement is represented by time on the horizontal axis and the movement distance in the X-axis direction on the vertical axis. FIG. 20 shows an XZ combined movement distance that is a movement distance obtained by combining the movement distance in the Z-axis direction. Furthermore, the state of the vibration cutting movement of FIG. 20 is shown in FIG. 21 by setting the horizontal axis as time, the vertical axis as the movement distance for each axis in the X-axis direction and the Z-axis direction, and the movement distance for each XZ-axis. Show. FIG. 21 shows that the X-axis clamping speed and the Z-axis clamping speed can be compared with the X-axis vibration superposition speed and the Z-axis vibration superposition speed. 22 and 23, the X-axis and Z-axis vibration cutting operations collectively shown in FIG. 21 are shown separately with the vertical axis as the X-axis movement distance and the Z-axis movement distance, respectively.

FIG. 22 shows that the X-axis clamping speed can be compared with the X-axis vibration superposition speed at the time of vibration advance, and the X-axis vibration superposition speed at the time of vibration advance is larger than the X-axis clamp speed. Therefore, the X-axis “clamp ratio” = 0.95883, which is a value obtained by dividing the X-axis clamp speed by the X-axis vibration superposition speed at the time of forward movement, is also shown.

FIG. 23 shows that the Z-axis clamping speed can be compared with the Z-axis vibration superposition speed at the time of vibration advance, and the Z-axis vibration superposition speed at the time of vibration advance is larger than the Z-axis clamp speed. Therefore, the Z-axis “clamp ratio” = 0.7986, which is a value obtained by dividing the Z-axis clamp speed by the Z-axis vibration superposition speed at the time of forward movement, is also shown.

The numerical control device 2 according to the third embodiment executes actual speed clamping, that is, suppression of actual speed according to the flowchart of FIG. First, the vibration speed clamp unit 485 reads the X-axis clamp speed and the Z-axis clamp speed stored as the actual speed clamp 4311 from the storage unit 43 (step S201). Next, based on the machining program 432 in FIG. 18 and the vibration cutting conditions shown in FIG. 10, the post-vibration superposition speed calculation unit 484 calculates post-vibration superposition speeds for the X axis and the Z axis (step S202). Specifically, for each of the X-axis and the Z-axis, both “forward vibration superposition speed” and “reverse vibration superposition speed” are calculated for each axis. The calculation method of “forward vibration superposition speed” and “reverse vibration superposition speed” for each axis is the same as in the first embodiment.

Then, in step S203, the vibration speed clamp unit 485 determines whether or not the vibration superposed speeds of the X axis and the Z axis exceed the X axis clamp speed and the Z axis clamp speed, respectively.

In step S203, the vibration speed clamp unit 485 determines that the larger of the “forward vibration superposition speed” and the “reverse vibration superposition speed” of the X axis exceeds the clamp speed or the Z axis “forward vibration superposition speed”. ”And“ reverse vibration superimposition speed ”is judged whether or not the clamp speed exceeds the clamp speed. Since this comparison also needs to be able to compare the post-superimposition speed and the clamping speed for each axis, it may be a comparison between the movement amounts in a predetermined time instead of a comparison between the speeds. .

Both the X-axis “forward vibration superposition speed” and “reverse vibration superposition speed” do not exceed the X-axis clamp speed, and either the Z-axis “forward vibration superposition speed” or “reverse vibration superposition speed” If the motor does not exceed the Z-axis clamping speed (step S203: No), the interpolation processing unit 48 performs a normal operation without clamping the “feed speed” (step S205).

When either the X-axis "superimposing vibration speed during forward movement" or "reverse vibration superimposing speed" exceeds the X-axis clamping speed or the Z-axis "superimposing vibration speed during forward movement" or "reverse vibration superimposition speed" If either exceeds the Z-axis clamp speed (step S203: Yes), the vibration speed clamp unit 485 clamps the “feed speed” (step S204). Specifically, neither the X-axis “forward vibration superposition speed” nor the “reverse vibration superposition speed” exceeds the X-axis clamp speed, and the Z-axis “forward vibration superposition speed” and “reverse time”. In order to prevent any of the “superimposed vibration speeds” from exceeding the Z-axis clamping speed, the “clamping ratio” of the X axis obtained in FIG. 22 is 0.9583, and the “clamping ratio of the Z axis obtained in FIG. The smaller “clamp ratio” of “= 0.986” is used. Therefore, the vibration speed clamp unit 485 sets a value obtained by multiplying “feed rate” by “clamp ratio” = 0.7986 as a new “feed rate”. Specifically, it is assumed that the “feed speed” commanded by “F50” of the sequence number “N3” in FIG. 18 is replaced with a value multiplied by “clamp ratio” = 0.7986 shown in FIG. The interpolation processing unit 48 performs subsequent calculations. The “clamp ratio” may be equal to or less than the value determined as described above.

In step S204, as described above, when the “feed rate” is clamped with the smaller “clamp ratio” = 0.7986, the state of the vibration cutting movement is as follows: the horizontal axis is time, the vertical axis is the X axis direction, and the Z axis. FIG. 25 shows the XZ combined movement distance, which is the movement distance obtained by combining the directions. Furthermore, the state of the vibration cutting movement of FIG. 25 is shown in FIG. 26 with the X-axis and Z-axis, the horizontal axis as time, and the vertical axis as the movement distance by XZ-axis, which is the movement distance by axis in the X-axis direction and Z-axis direction. Show. FIG. 26 shows the X-axis clamp speed and the Z-axis clamp speed so that they can be compared with the X-axis vibration superposition speed and the Z-axis vibration superposition speed. Further, in FIGS. 27 and 28, the operations of the X-axis and the Z-axis collectively shown in FIG. 26 are shown separately with the vertical axis as the X-axis movement distance and the Z-axis movement distance, respectively.

Since the “feed speed” is clamped with the smaller “clamp ratio” = 0.986 obtained for the Z-axis in FIG. 23, the speed after superimposing vibrations in the X-axis direction and the Z-axis direction is as shown in FIG. As shown in FIG. 4, the X-axis clamp speed and the Z-axis clamp speed are respectively suppressed. As shown in FIGS. 26 and 28, the speed after Z-axis vibration superposition coincides with the Z-axis clamping speed.

The clamping speed for clamping the feeding speed is not limited to that described in the first to third embodiments. For example, the cutting speed is a clamping speed applied to all cutting feeds, and only during the vibration cutting mode. There are a cutting feed clamping speed during the vibration cutting mode, which is an effective clamping speed, and a clamping speed based on a maximum cutting feed speed clamping command from a PLC (programmable logic controller). In actual machining, it is necessary to set the smallest feed speed in consideration of these clamping speeds. Therefore, the speed clamping methods of the first to third embodiments can be applied in the same manner when these clamping speeds are taken into consideration.

The configuration described in the above embodiment shows an example of the contents of the present invention, and can be combined with another known technique, and can be combined with other configurations without departing from the gist of the present invention. It is also possible to omit or change the part.

1 numerical controller, 10 drive unit, 11 servo motor, 12 detector, 13 servo control unit, 13X X-axis servo control unit, 13Z Z-axis servo control unit, 14 spindle motor, 15 detector, 16 spindle control unit, 20 Input operation unit, 30 display unit, 40 control operation unit, 41 input control unit, 42 data setting unit, 43 storage unit, 44 screen processing unit, 45 analysis processing unit, 46 machine control signal processing unit, 47 PLC circuit unit, 48 Interpolation processing unit, 49 acceleration / deceleration processing unit, 50 axis data output unit, 61 machining target, 62 tool, 431 parameter, 432 machining program, 433 screen display data, 434 shared area, 451 movement command generation unit, 452 vibration command analysis unit , 453 Actual speed clamp command analysis unit, 481 Command movement amount calculation unit, 482 Dynamic movement amount calculating section, 483 movement amount superimposing unit, 484 vibration superimposed after the speed calculation portion, 485 vibration velocity clamp unit, 4311 actual speed clamps.

Claims

A numerical control device that performs processing of the processing target by moving the tool and the processing target along a movement path while relatively vibrating with a drive shaft provided on the tool or processing target,
An analysis processing unit that reads a feed speed and a clamp speed in the movement path from a machining program;
Based on a given vibration cutting condition, a post-vibration superposition speed calculation unit that calculates a post-superimposition speed after the superposition of the vibration on the movement at the feed rate;
When the vibration superposition speed exceeds the clamp speed, a vibration speed clamp unit that reduces the feed speed to be equal to or less than the clamp speed;
A numerical control device comprising:
A numerical control device that performs processing of the processing target by moving the tool and the processing target along a movement path while relatively vibrating with a drive shaft provided on the tool or processing target,
From a machining program, an analysis processing unit that reads a feed rate in the movement path,
A storage unit for holding the clamping speed;
Based on a given vibration cutting condition, a post-vibration superposition speed calculation unit that calculates a post-superimposition speed after the superposition of the vibration on the movement at the feed rate;
When the vibration superposition speed exceeds the clamp speed, a vibration speed clamp unit that reduces the feed speed to be equal to or less than the clamp speed;
A numerical control device comprising:
A plurality of the drive shafts are provided on the tool or the processing target,
The storage unit holds a plurality of the clamping speeds for each drive shaft,
The post-vibration superposition speed calculation unit calculates the post-vibration superposition speed for each drive shaft,
When any of the vibration superposed speeds for each of the drive shafts exceeds the clamp speed of the drive shafts, the vibration speed clamp unit is configured so that each of the post-vibration superposed speeds of the plurality of drive shafts corresponds to the drive shafts. The numerical control apparatus according to claim 2, wherein the feed speed is reduced so as to be equal to or less than the clamp speed.
4. The vibration speed clamp unit reduces the feed speed by multiplying the feed speed by a clamp ratio that is a value obtained by dividing the clamp speed by the post-vibration superposition speed. The numerical control device according to claim 1.