JP2015079491A - Processing data calculation device and processing data calculation program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To slow down a speed in processing for only a portion where a problem occurs in processing without decreasing processing efficiency.SOLUTION: Drawing data representing a processing tool locus is generated to display the processing tool locus using the generated drawing data on a display screen of a display device, and an input is received of a designation section in which a processing speed designated on the processing tool locus displayed on the display screen is changed. Without changing the processing tool locus corresponding to the designation section, by extending or shortening a passing time that the tool passes through the designation section, shaft control data is changed so that the speed in each position of the designation section changes the original speed.

Description

  The present invention relates to a machining data calculation device and a machining data calculation program for generating machining data for machining with a machining machine.

  In general, a numerical control device of a cutting machine decodes an input NC program, calculates position data, and distributes and outputs a movement command value to the motor control device of each axis. Therefore, the initial feed speed and maximum acceleration may not be able to bend with a curve with a large curvature, so the feed speed and maximum acceleration are set according to the maximum curvature of all the tool path curves during the machining process. There is a need to. Therefore, the machining speed is improved by changing and outputting the feed speed or the maximum acceleration corresponding to the curvature of the curve (for example, Patent Document 1).

  However, when the maximum feed speed and the maximum machining speed are set so as to be the maximum in a straight line, the cutting direction changes abruptly when actually machining, even though no problem was found in the simulation before machining. By the way, the tool may behave unexpectedly. Such a phenomenon is not limited to the case where the processing machine cannot cope with the NC program that is theoretically correctly created. For example, when the installation environment of the processing machine is changed, or when a specific processing is performed. It often occurs when the NC program used for machining in a machine is used for another machine with the same structure. In such a case, it is required to change the initially set feed speed or to change the feed speed or acceleration in a predetermined section.

JP 2012-137990 A

  However, if the initially set feed speed and set acceleration are changed, the feed speed on the straight line becomes smaller and the machining efficiency is lowered. Therefore, in order not to reduce the machining efficiency, it is required to change the feed speed and the set acceleration only in necessary portions. On the other hand, in recent years, with the spread of 3D CAD, complex finished shapes have been designed with 3D CAD, and NC programs for machining complex shapes defined by solid data are automatically generated. It has become like this. In such a complicated finished shape, it is very difficult to directly identify the part that behaves unexpectedly on the NC data. Further, even if the NC program block (section) corresponding to the unexpected behavior portion can be determined, the operator can select one or more corresponding program blocks and the program blocks before and after the program block. It is almost impossible to change the NC program so that the speed and acceleration change smoothly between the two. Therefore, the operator cannot substantially change the feed speed and acceleration in an arbitrary section.

  Accordingly, an object of the present invention is to provide a machining data calculation device and its program for changing machining data so as to change the feed rate only in a portion where a defect appears during machining without reducing machining efficiency. It is.

The machining data calculation device according to the present invention is configured to divide each of the plurality of divided tracks obtained by dividing the tool track in order to move the tool by controlling a plurality of control axes at a specified processing speed along a predetermined tool track. Axis control data storage means for storing a plurality of axis control data representing a change in speed with respect to the time of each control axis of the tool and the position of at least one point on the divided locus corresponding to the locus,
In accordance with the plurality of axis control data, a drawing display unit that generates drawing data representing a machining tool path, and displays the machining tool path on a display screen of a display device using the generated drawing data;
A designated section receiving means for receiving an input of a designated section for changing the machining speed designated on the machining tool trajectory displayed on the display screen;
The original speed at which the speed at each position in the designated section is determined by the axis control data by extending or shortening the passing time for the tool to pass through the designated section without changing the machining tool trajectory corresponding to the designated section. And an axis control data changing means for changing the axis control data corresponding to the designated section.

  In particular, the machining data calculation device of the present invention includes an NC data generating unit that decodes an NC program to generate NC data, an axis control data generating unit that analyzes the NC data and generates the axis control data, It is characterized by comprising.

Further, the machining data calculation program of the present invention includes a computer,
In order to move a tool by controlling a plurality of control axes at a specified machining speed along a predetermined tool path, the divided path corresponding to each of the divided paths of the plurality of divided paths divided from the tool path Axis control data storage means for storing a plurality of axis control data representing speed changes with respect to time of each axis position of the starting point and each control axis of the tool;
In accordance with the plurality of axis control data, a drawing display unit that generates drawing data representing a machining tool path, and displays the machining tool path on a display screen of a display device using the generated drawing data;
A designated section receiving means for receiving an input of a designated section for changing the machining speed designated on the machining tool trajectory displayed on the display screen;
The original speed at which the speed at each position in the designated section is determined by the axis control data by extending or shortening the passing time for the tool to pass through the designated section without changing the machining tool trajectory corresponding to the designated section. So as to change the axis control data corresponding to the specified section.

  “Axis control data” refers to data for controlling each axis when the machining position of the tool is moved according to the division trajectory.

  The “machining tool trajectory” refers to a trajectory along which the tool moves according to the axis control data, and substantially coincides with the “predetermined tool trajectory”. The “machining tool trajectory” is determined so that the difference between the “predetermined tool trajectory” falls within a predetermined error range. The range of the error is appropriately determined empirically according to the size of the workpiece and the amount of material of the workpiece.

  The axis control data was converted into the axis control data by analyzing the NC code specified by the NC program and the tool path obtained from the coordinate value of each axis and the machining speed specified by the NC program. It may be a thing.

  The axis control data changing unit may further include a deceleration rate accepting unit that accepts a rate of deceleration with respect to a current machining speed of the designated section in the designated section, and the axis control data changing unit responds to the rate of deceleration of the designated section. It is desirable to change the axis control data so as to achieve a desired speed.

  Furthermore, the specified section receiving means may receive a machining tool trajectory displayed within a range surrounded by a predetermined shape on the display screen as the specified section.

  In the present invention, a specified section for changing the machining speed is set on the machining tool path displayed on the display screen, and the tool passes through the specified section without changing the machining tool path corresponding to the specified section. By extending the time and changing the speed so that it becomes smaller than the machining speed specified in advance, it becomes possible to specify on the display screen the part where defects appear when actually machining, and the overall machining speed Since the machining speed can be changed only for the portion to be decelerated without changing the machining speed, the machining accuracy can be improved without extending the machining time more than necessary.

  Also, by displaying the machining tool trajectory on the display screen using the axis control data generated by analyzing the NC program, using the proven NC program, only the part of the machining where the defect appears The processing speed can be changed.

  Furthermore, it is possible to specify a specified section that spans multiple layers by specifying a specified section that changes the machining speed of the machining tool trajectory that appears on the display screen using a predetermined shape. Become.

Schematic configuration diagram of processing system Configuration diagram of the drive unit of the processing machine Configuration diagram of machining control device Configuration diagram of machining data generator The figure for explaining how to find the division trajectory by dividing the tool trajectory Diagram showing the relationship between division trajectory and machining speed Diagram showing speed change of each axis An example of displaying the tool path for machining by simulation Illustration for explaining the specified section Example showing X axis speed change Example showing rate change of synthesis rate Operation and processing flow for changing the speed of axis control data

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram of a machining system including a machining data arithmetic device according to the present invention.

  A machining system 1 according to the present invention includes a CAM device 2 that creates a machining shape, a machining control device (numerical control device) 3 that controls a machining machine, and a workpiece (workpiece) that is placed on a table and uses a tool to place the workpiece. And a processing machine 4 for processing. The CAM device 2 and the processing control device 3 are connected via a network 5.

  The processing machine 4 includes a main shaft (processing head) 41 to which a tool is attached, a table 42A on which a workpiece is installed, a saddle 42B that moves the table 42A, and a drive unit 43 that drives each shaft (main shaft, feed shaft). Is provided. Usually, the main shaft is a shaft for transmitting cutting power. In the case of a vertical processing machine in which the main shaft is in the vertical direction as in the embodiment shown in FIG. 1, the main shaft is represented as the Z axis and is orthogonal to each other for moving the table 42. Two feed axes in the horizontal direction are represented as an X axis and a Y axis, respectively.

  As shown in FIG. 2, the drive unit 43 includes an axis control data receiving unit 44 that receives axis control data A for controlling each axis from the machining control device 3, and the X axis, Y axis, and Z axis according to the axis control data A. A command value calculation unit 45 that generates an actual command value necessary to actually drive and control each axis linear motor, motor control units 46a, 46b, and 46c that feedback control the linear motor of each axis, and a table for each axis Linear motors 48a, 48b, and 48c for moving a moving body such as 42, and linear amplifiers 47a, 47b, and 47c that output drive current to the linear motors 48a, 48b, and 48c, respectively.

  The motor control units 46a, 46b, 46c are detected by the actual command values received from the command value calculation unit 45 and the detection positions px, py, pz and speeds vx, vy obtained from linear encoders (not shown) provided on the respective axes. , Vz are output to the linear amplifiers 47a, 47b, 47c with actual command values compensated for position and speed. The linear amplifiers 47a, 47b, 47c output drive currents corresponding to the received actual command values to the linear motors 48a, 48b, 48c. The linear amplifiers 47a, 47b, and 47c have a function of performing current compensation by feeding back the drive currents ix, iy, and iz of the linear motors 48a, 48b, and 48c.

  As shown in FIG. 3, the machining control device 3 is provided with a dedicated computer including at least a CPU and a memory, and further includes a display unit 31, an operation unit 32, and an input / output unit 33. The dedicated computer incorporates software such as an operating system and control software for controlling the processing machine, a parameter storage unit 34 for storing various parameters, and an axis control data storage unit for storing axis control data A 35. A simulation unit 36 that simulates a machining tool path before machining, and an axis control data output unit 37 that outputs axis control data A to the drive unit 43.

  Specifically, the display unit 31 is a display device such as a cathode ray tube (CRT) or a liquid crystal display (LCD) device including a conversion device that converts image data into display data.

  The operation unit 32 includes an operation panel and is used for inputting a control command or data. Alternatively, a touch panel may be provided on the display device so that an icon composed of a small picture or symbol displayed on the display unit 31 can be selected to perform interactive input. Furthermore, it is preferable that the touch panel is provided with a pointing device such as a stylus pen so that a specific region of the machining tool trajectory displayed on the display unit 31 by simulation can be selected.

  The input / output unit 33 is connected to the network 5 and transmits and receives NC program or tool path data between the CAM device 2 and the machining control device 3 via the LAN. Alternatively, the input / output unit 33 causes the machining control device 3 to take in NC program data or tool path data from the storage medium. The NC program or tool path data received through the input / output unit 33 can be stored in the axis control data calculation unit 35. In the following description, for convenience, the tool path data may be referred to as curve data (parametric curve) as necessary.

  The parameter storage unit 34 stores parameters such as maximum acceleration and maximum jerk as internal setting values unique to the machine depending on the physical characteristics of each processing machine 4, and controls each axis according to the parameter value. Is called. Further, since the maximum acceleration, the maximum jerk, and the like differ depending on the attached tool, parameters are set according to the tool. In addition, the parameter storage unit 34 stores data of arbitrary parameters given by a program creator or an operator such as a set feed speed, a set acceleration, and the number of rotations of a tool. When a plurality of values corresponding to the tool diameter or the like are given by one type of parameter, they are stored in association with the tool path data. The NC program is preliminarily provided with data of plural types of parameters, and the values of the plural types of parameters included in the NC data obtained by decoding the NC program are stored in the parameter storage unit 34. . When only the tool path data is acquired from the CAM device 2, the operator inputs a plurality of types of parameter values required in association with the tool path data and stores them in the parameter storage unit 34.

  Based on the axis control data stored in the axis control data calculation unit 35, the simulation unit 36 simulates the machining tool trajectory before machining and displays it on the display unit 31.

  The CAM device 2 is composed of a general-purpose computer (for example, a personal computer or a workstation), connected to a data storage device or an interface unit for connecting to the network 5, a mouse, a keyboard, an input device such as a touch panel, and the like. A display device such as a display is provided. The CAM device 2 is installed with standard software such as an operating system and dedicated application software such as software for searching and selecting machining conditions or software for supporting creation of NC programs. The CAM device 2 functions as a device that generates NC program or tool path data using dedicated software. In addition to the machining control device 3, the CAM device 2 interacts with a storage device of an external device such as a server in which existing NC programs used for machining in the past are stored, or other personal computers. Connected to.

  As shown in FIG. 4, the machining data calculation device of the embodiment is mainly configured by an axis control data calculation unit 35 of the machining control device 3. Specifically, the axis control data calculation unit 35 includes an NC program storage unit 35A, an NC program decoding unit 35B, a tool path generation unit 35C, a tool path storage unit 35D, an axis control data generation unit 35E, an axis control data storage unit 35F, A drawing display unit 35G, a designated section receiving unit 35H, an axis control data changing unit 35I, and a deceleration rate receiving unit 35J are provided. However, in an environment where the CAM device 2 and the machining control device 3 can be always connected via a communication line, one or more of the axis control data calculation units 35 of the machining control device 3 according to the embodiment. Each of the above means can be provided in the CAM device 2. Therefore, in the present invention, when the above means is provided in the CAM device 2, the above means provided in the CAM device 2 is referred to as a machining data arithmetic device.

  The NC program includes NC codes (G01: linear interpolation, G02 or G03: circular interpolation, etc.), coordinate values of tool axes (X axis, Y axis, Z axis), feed speed (F value, hereinafter) The value of a parameter such as that described as the processing speed is recorded. Further, many NC programs have been used for machining in the past, and a reliable shape is defined. When the same product is processed again with another processing machine, it is often corrected and processed based on NC programs used for processing in the past.

  The NC program storage means 35A is a storage device such as a hard disk, and stores an NC program given from a portable recording medium connected to the CAM device 2 or USB (Universal Serial Bus) through the input / output unit 33. . It is also possible to read an old paper tape recording an NC program of the old asset from a paper tape reader connected to the serial port.

  The NC program decoding means 35B is selected by the operator from the NC program storage means 35A when the operator selects an NC program file stored in the NC program storage means 35A and executes the NC program. The read NC program is read, and the read NC program is sequentially decoded in the order programmed for each program block to generate NC data. Among the generated NC data, NC data including data defining the shape of the tool path such as the NC code and the position data related to relative movement is output to the tool path generating means 35C. Further, NC data related to parameters including processing conditions is output to the parameter storage unit 34. In addition, for example, data relating to driving of the spindle rotating shaft (spindle), data relating to driving of the pump or valve of the machining fluid supply device, NC code not directly related to the present invention such as driving of the magazine or arm of the tool changer are included. The NC data is output to each control unit for outputting a command signal to each axis or each device including a dedicated control device, but detailed description thereof is omitted.

  The tool trajectory generating means 35C includes NC data including data defining the shape of the tool trajectory such as NC code and position data related to relative movement obtained by decoding the NC program, for example, G code and coordinate values of each axis. Is analyzed and converted into parametric curves such as multiple NURBS (Non-Uniform Rational B-Spline) so that the error with the tool path defined in the NC program falls within the specified range. To do. The range of error is a range determined empirically, and is determined by the processing object, the processing shape, and the like.

  The tool path storage unit 35D stores the data of the tool path (parametric curve) generated by the tool path generation unit 35C as a file. When only the tool path (curve) data is given from the CAD device 2 or the storage medium through the input / output unit 33, the tool path storage unit 35D stores the given tool path data as a file. Can do.

  The axis control data generation unit 35E further includes a divided trajectory calculation unit 35E-1 and an axis control data calculation unit 35E-2, and is converted into a parametric curve using the machining speed F specified by the NC program. The tool path L is converted into axis control data A. In the calculation for generating the following axis control data A, the calculation is performed using the parameters stored in the parameter storage unit 34. The operator corresponds to the processing machine that outputs the axis control data A in advance by the operator. Which processing machine parameter to use is selected.

  The divided locus calculation means 35E-1 obtains a divided locus obtained by dividing the tool locus L in accordance with the curvature of the tool locus L converted into a parametric curve. The processing machine 4 processes the workpiece by moving the processing position of the tool while controlling the speed of each axis between the two specified points. However, in the portion where the curvature of the tool locus L is large, the moment of inertia of the processing machine 4 is processed. There is a portion where it is difficult to move the machining position of the tool along the tool path L due to the influence of rigidity and rigidity. Further, it is preferable that the tool locus L connecting the two points designated to the processing machine 4 does not deviate greatly from the straight line. Therefore, the curvature of the tool locus L is obtained, and as shown in FIG. 5, the tool locus L is divided at large intervals where the curvature is small, and is divided at small intervals as the curvature increases, and a point P1 on the tool locus L is obtained. , P2, P3, P4,..., Pi, Pi + 1, and so on, are divided into a plurality of division trajectories l1, l2, l3, l4,. For example, the tool trajectory L in the range where the curvature of the tool trajectory is small (the curvature is close to 0) and is a substantially straight line is set as one divided trajectory. That is, where a portion close to a straight line continues, a long-distance tool locus becomes one divided locus l, and where the curvature is large, the divided locus l is generated at short intervals.

  The axis control data calculating means 35E-2 uses the divided trajectory when the tool is moved at the specified machining speed F along the divided trajectories l1, l2, l3, l4,. Axis control data A in which a movement command value represented by a time change of the speed of each axis obtained at a predetermined time interval and the position of each axis at a point on l is obtained. The axis control data A only needs to include at least one axis position on the divided trajectory. For example, if the axis control data A records the position of the starting point on the divided locus l and the speed change of each axis when moving along the divided locus, each axis is designated from the position of the starting point. By controlling each axis so as to follow the speed change, the tool can be moved along the division locus l to the machining position of the tool.

  In order to machine a workpiece at a designated machining speed F along the division trajectory l as shown in FIG. 6, the machining position of the tool is moved in the tangential direction at the machining speed F at each position on the division trajectory l. Thus, the machining position of the tool can be moved along the division locus l. That is, the processing speed F is divided into components X, Y, and Z of each axis of the tangent vector at each position of the divided locus l, the X axis is moved by the speed component in the X direction from the position of the starting point, and the Y axis is moved in the Y direction. It is possible to move the machining position of the tool along the division trajectory by controlling the Z axis to move with the velocity component in the Z direction. As shown in FIG. 6, the velocity component of each axis at the start point position P1 on the divided locus l is (V1x, V1y, V1z), and the velocity component of each axis at the end point position P2 is (V2x, V2y, V2z), the speed of each axis is changed from V1x → V2x, V1y → V2y, and V1z → V2z while moving each axis from the position P1 to P2. Further, in order to move the tool along the division locus l, it is necessary to change the speed of each axis at short time intervals so that the traveling direction of the tool is in the tangential direction of the division locus.

  Therefore, as shown in FIG. 7, a speed curve representing the time change of the speeds Vx, Vy, and Vz for moving the respective axes when the tool is moved at the machining speed F on each divided locus l is obtained. FIG. 7 shows a case where there is no movement in the Z direction and there is a movement only in the XY plane. By controlling the speed of each axis so as to follow this speed curve, the machining position can be moved along the division locus l. Therefore, in the axis control data A, for example, the speed of each axis at each point obtained by dividing the speed curve of each axis at a short constant time interval Δt and the starting point of the divided locus l are recorded.

  Since there is a limit on the maximum acceleration and the maximum jerk in the processing machine 4, there is a place where the processing position of the tool cannot be moved along the divided locus l while maintaining the specified processing speed F. Therefore, based on the parameters relating to the maximum acceleration and the maximum jerk, the curvature of the divided locus 1 at the machining position is large, and when the machining is performed at the machining speed F, it is predicted that machining cannot be performed along the divided locus l. The speed in each axial direction is determined so as to be smaller than the specified processing speed F. Specifically, based on the curvature of the divided trajectory at each point obtained by dividing the divided trajectory at the time interval Δt, the acceleration and jerk when the axes are moved at the designated processing speed F are obtained. The portion where the jerk exceeds the maximum acceleration or maximum jerk of the processing machine 4 set in the parameters, the movement speed of the machining position is made smaller than the machining speed F and exceeds the maximum acceleration or maximum jerk. The axis control data A is generated by determining the speed in each axis direction so as not to be present.

  Further, since the integral value of the speed curve from time T0 to time Tn shown in FIG. 7 is the distance moved from time T0 to time Tn, the position of each axis at time Tn is the starting point P0 of the divided locus l. The position of each axis is obtained by adding an integral value between T0 and Tn of the speed curve.

  Here, the case where the speed of each axis is recorded in the axis control data A at a constant time interval Δt will be described. However, when the speed does not change as in the case of moving the machining position of the tool on a straight line. The speed of each axis may not be recorded in the linear movement section. Further, the speed may be recorded at a large time interval in a section with a small curvature, and the speed may be recorded at a small time interval in a section with a large curvature, and the speed may not be recorded at a constant time interval. If the time interval is not constant, the time interval at which the speed is recorded in the axis control data A is also recorded. When always recording speed at a fixed time interval, the speed must be recorded at the smallest time interval so that accuracy can be maintained, but by changing the time interval according to the curvature, , Can reduce the amount of data.

  By each of the above processes, one tool path block (range defined by the G code) that is usually represented by one program block defined by the NC program becomes a machining tool path defined by the axis control data. Is often converted to a plurality of axis control data A so that the tool path is not greatly deviated from the actual tool path. For example, a long single linear tool path is specified by a plurality of program blocks. In the portion formed by the locus blocks, a plurality of tool locus blocks may be converted into one axis control data A. The generated axis control data A is recorded in a file in order from the machining start position of the tool path, and is temporarily stored in the hard disk (axis control data storage means 35F).

The drawing display means 35G generates drawing data representing a machining tool locus in accordance with the axis control data A recorded in the file stored in the axis control data storage means 35F, and uses the generated drawing data for machining. The tool path is displayed on the display screen of the display device. First, the position of the starting point P (T0) is read from the head axis control data A, and each axis (X axis, Y axis) is read from the position of the starting point P (T0) at the speed V (T0) recorded in the axis control data A. , The Z axis) is generated on the display device by generating drawing data representing the tool trajectory for machining up to the position P (T1) = P (T0) + V (T0) · Δt obtained by moving the machining position during time Δt. To display. Further, the position P (T2) = P (T1) + V (where the machining position is moved during the time Δt at the speed V (T1) of each axis after the next Δt time recorded in the axis control data A. Drawing data representing the machining tool trajectory up to T1) .DELTA.t is generated and displayed on the display device. In this way, drawing data representing the machining tool trajectory when the machining position is moved during the time Δt at the speed of each axis recorded in the axis control data A at the time interval Δt is generated, Sequentially displayed on the display device. The following equation (1) shows the relationship between the i-th position P (Ti), the velocity V (Ti) at that position, and the i + 1st position P (Ti + 1).
P (Ti + 1) = P (Ti) + V (Ti) · Δt (1)

  The designated section accepting unit 35H accepts the designated section as a section for changing the degree of change in speed on the machining tool trajectory displayed on the display screen. Specifically, the processing tool trajectory displayed on the display screen is surrounded by a curve or a predetermined shape by the operator using a pointing device such as a mouse, and the processing tool exists within the enclosed range. A trajectory is accepted as a specified section. Here, the degree of change in speed is the rate of increase or decrease when the speed difference between the speed at a certain position and the speed at a position away from that position by a unit distance increases or decreases for each unit distance. Indicates. Therefore, when the degree of speed change is large, the degree to which the speed difference between unit distances increases or decreases each time the unit distance advances is larger, and when the degree of speed change is small, the unit distance per unit distance advances. The degree to which the speed difference between increases or decreases is small.

  Normally, the machining tool trajectory defined by the axis control data A is simulated by the CAM device 2 or the machining control device 3 before actual machining, but does not appear in the simulation when the machining is actually performed. A bug may appear. In many cases, there is a high possibility that the processing direction will change greatly like a corner portion. For example, as shown in FIG. 8, when processing a plurality of layers in a contour line, a line due to tool vibration may appear at the same corner portion of each layer. For example, a corner portion where such a defect appears is surrounded by a rectangular shape (broken line in FIG. 8) using a pointing device on the machining tool trajectory displayed on the display device to be a designated section. As shown in FIG. 8, the corner portions of a plurality of layers can be collectively set as a designated section. Here, the case where the designated section is designated by a rectangular shape will be described. However, other shapes such as a circle may be used, and a free curve may be used as long as the enclosed range can be specified.

  The deceleration rate accepting unit 35J accepts the setting of the degree of speed change in an arbitrary designated section on the tool trajectory, in other words, the rate of deceleration with respect to the current speed in the arbitrary designated section. Hereinafter, the degree of change in the speed is referred to as a partial deceleration rate. The partial deceleration rate is set by the operator using a GUI (graphical user interface) or the like. In this embodiment, the partial deceleration rate is set at a ratio (override value) of 100% or less, assuming that the initial setting value is 100%.

  The axis control data changing means 35I recalculates the speed change in the designated section given by the designated section receiving means 35H according to the reduced partial deceleration rate given through the deceleration rate accepting means 35J and rewrites the axis control data. Hereinafter, the operation of the axis control data changing unit 35I will be specifically described with reference to FIGS.

  FIG. 9 shows the designated section of one layer among the designated sections of the plurality of layers designated in FIG. Further, the machining is performed in the direction of the arrow on the machining tool locus in FIG. In FIG. 8, the designated section covers three axis control data A1, A2, and A3. The range (shaded part) from the start point Ps to the final position in the axis control data A1 corresponds to the specified section, the entire range of the axis control data A2 corresponds to the specified section, and the start position to the end point in the axis control data A3. The range up to Pe (shaded portion) corresponds to the designated section.

  FIG. 10 shows the change in the velocity Vx in the x-axis direction with respect to time t. H1 (t) represents a change in speed before changing the partial deceleration rate, and the designated section is from ts (start time) to te (end time). Before changing the partial deceleration rate, the specified section is passed at time Q1 = te−ts. The speed at the start time ts is Vs, and the speed at the end time te is Ve. H2 (t) represents the change in speed after the change. Specifically, in the case of the specified section of the curve as shown in FIG. 9, the speed at each position of the machining tool trajectory is gradually decreased from the starting point Ps of the specified section, and the speed is most decelerated at the intermediate point of the specified section. Try to be speed. The speed is returned to the speed Ve before the change from the point past the intermediate point to the end point Pe of the designated section. The passing time for passing the tool through the specified section is extended by ΔQ, and the passing time of the specified section is Q2 = Q1 + ΔQ. The speeds of the Y-axis and Z-axis are similarly changed, but are determined so that the machining position moves in the tangential direction at each position on the machining tool trajectory.

  The basic concept is to set the passing time for the tool to pass through the specified section so that the partial deceleration rate is small without changing the machining tool trajectory in the range from the start point Ps to the end point Pe of the axis control data A1, A2, A3. Extend and change the axis control data A corresponding to the specified section. FIG. 8 shows a state in which the range of the axis control data A corresponding to the specified section is specified for one layer, but the axis control data A (A1, A2, A2) corresponding to the specified section of all the layers specified in FIG. The range of A3) is specified and the axis control data A is changed.

  The axis control data changing unit 35I first specifies the range of the axis control data A corresponding to the designated section designated on the machining tool trajectory displayed on the display screen by the operator. At this time, the machining tool trajectory on the display screen is drawn based on the axis control data represented by the time change of the speed, not just a collection of position data, so the designation designated by the designated section receiving means 35H. By specifying the positions of the start point and end point of the section, the respective speeds, accelerations, and times at the specified start point and end point can be obtained. For example, in FIG. 9, the start point Ps and the end point Pe are specified by obtaining the intersection of the line surrounded by the operator and the displayed machining tool path, and the specified start point Ps and end point Pe are shown in FIG. The speed Vs, acceleration, and time ts at the start point Ps shown, and the speed Ve, acceleration, and time te at the end point Pe can be respectively obtained.

  If the speed is too high, the curve cannot be bent completely, so the partial deceleration rate in the specified section may be made smaller. However, the operator cannot set the partial deceleration rate with the tool locus data based on the NC program. Since the machining data calculation device according to the embodiment of the present invention includes the axis control data changing unit 35I and the deceleration rate receiving unit 35J, the speed can be changed according to the partial deceleration rate in the designated section. Specifically, when the operator gives an override value of the partial deceleration rate through the deceleration rate receiving means 35J and decreases the speed, the axis control data changing means 35I changes the designated section so that the speed changes according to the given partial deceleration rate. Rewrite the axis control data inside. At this time, since the speeds must be connected before and after the designated section, the speed Vs and acceleration at the start point Ps and the speed Ve and acceleration at the end point Pe of the designated section are not changed. Further, when the partial deceleration rate changes at an arbitrary time while passing through the specified section, the speed, acceleration, and jerk at that time change.

For this reason, the axis control data changing unit 35I sequentially starts from the starting point position Ps, the speed Vs, and the time ts, and at the time tsn (= ts + Δt · n, n: corresponding to a predetermined time interval in the designated section. For each natural number), a recalculated speed Vsni is obtained according to the partial deceleration rate k given through the deceleration rate receiving means 35J. For example, as shown in FIG. 10, at the time ts1 after Δt time from the time ts of the start point Ps, the speed at the time ts1 changes the speed before and after the speed is recalculated because the speed changes from Vs1 to Vs1i. Deviation before and after. Assuming that the partial deceleration rate is k and the position Ps1 at the speed Vs1 at the time ts1 before the partial deceleration rate k is changed is at the same Ps1 at the time ti when the speed Vs1i is changed, the partial deceleration rate from the start point Ps. The time change ti and the arrival time ti after acceleration after changing k and recalculating the speed can be specified by the following equation (2). As a result, as shown in FIG. 10, when the partial deceleration rate changes, the time required to pass through the specified section is extended by time ΔQ1, but the tool trajectory in the specified section changes even if the partial deceleration rate changes. The speed change can be adjusted so that it does not occur.
ti = (Vs1 · Δt / Vs1i) (2)
However, Vs1i = Vs1 · k, ts = 0

  As described above, the time ti after the change is sequentially calculated from the speed and time before the change and the speed after the change for each time tsn without changing the tool trajectory, and before the partial deceleration rate is changed. A speed change H2 (t) changed by the partial deceleration rate given through the deceleration rate receiving means 35J from the speed change H1 (t) is obtained. Then, the axis control data changing unit 35I rewrites the axis control data A by the speed change H2 (t). The axis control data calculation means 35E-2 determines the speed of the axis control data A based on the maximum acceleration set by the parameter, but moves at the maximum machining speed F as much as possible based on the straight line. When the machining position of the tool is moved at the maximum acceleration that is set on the assumption, the tool may deviate from the specified tool locus in a curved portion where the curvature changes abruptly. Therefore, the axis control data changing unit 35I resets the maximum acceleration to a small value in accordance with the partial deceleration rate in the rewritten axis control data, and uses the same method as the axis control data calculating unit 35E-2 to perform the axis control data A Is calculated again. The processing speed and the maximum jerk may be reset and recalculated.

  Here, the position of the end point Pe in FIG. 9 corresponds to the area r1 of the region indicated by the oblique line surrounded by the speed change H1 (t) from the time ts of the start point Ps to the time te of the end point Pe in FIG. Further, this corresponds to the area r2 of the region indicated by the oblique line surrounded by the speed change H2 (t) after changing the partial deceleration rate k. If the position does not change at the end point Pe before and after the partial deceleration rate k is changed, the area r1 and the area r2 coincide. The curve H2 (t) can be obtained from the curve H1 (t) and the partial deceleration rate k. Therefore, instead of the method of sequentially obtaining the time ti for each time tsn and generating the curve H2 (t), the curve H2 (t) in which the area r2 coincides with the area r1 is obtained, and then the axis is set at a predetermined time interval. Control data can be reconstructed. In this case, there is an advantage that the changed axis control data can be obtained more easily.

  As described above, the speed change H2 (t) changed with the partial deceleration rate given through the deceleration rate receiving means 35J from the speed change H1 (t) before changing the partial deceleration rate without changing the tool trajectory. obtain. Then, the axis control data changing unit 35I rewrites the axis control data A by the speed change H2 (t). The axis control data changing unit 35I once sends the changed axis control data to the axis control data calculating unit 35E, and the axis control data calculating unit 35E reconfigures the axis control data at predetermined time intervals. The axis control data calculation means 35E-2 of the axis control data calculation means 35E determines the speed of the axis control data A based on the maximum acceleration set by the parameter. When the machining position of the tool is moved at the maximum acceleration set on the assumption that the tool moves at the speed F, the tool deviates from the specified tool path in the curved portion where the curvature changes rapidly. May end up. Therefore, the axis control data changing unit 35I resets the maximum acceleration to a small value in accordance with the partial deceleration rate in the rewritten axis control data, and uses the same method as the axis control data calculating unit 35E-2 to perform the axis control data A Is calculated again. The processing speed and the maximum jerk may be reset and recalculated.

  FIG. 11 shows a change in the composite speed F of the tool. G1 (t) represents a change in the synthesis speed before the change, and G2 (t) represents a change in the synthesis speed after the change. FIG. 11 shows an example in which the designated section is a portion having a large curvature such as a corner portion, so that the synthesis speed is lower than the machining speed F1 already designated before the change. After the change, the combined speed at each position on the machining tool trajectory in the designated section becomes smaller than the original speed, but in the section excluding the designated section, it matches the original speed before the change. FIG. 11 shows an example in which the combined speed of the start time ts and end time te of the specified section is F2 which is smaller than the machining speed F1. Even after the change, the speed is the same at F2 at the start time ts and the end time te + ΔQ. Further, the area (distance) R1 obtained by integrating the start time ts to the end time te of G1 (t) representing the synthesis speed is equal to the area R2 obtained by integrating the start time ts to the end time te + ΔQ of G2 (t). Thus, the speed after the change is determined, and the speed is distributed to the components in the respective axial directions. As shown in FIG. 10, the area r1 obtained by integrating the start time ts to the end time te of H1 (t) representing the movement distance of each axis and the start time ts to the end time te + ΔQ of H2 (t) are integrated. The areas r2 match.

  The axis control data changing unit 35I stores the axis control data in the entire series including the changed axis control data A in the storage unit 35E. The partially changed axis control data A can be stored in the NC program storage unit 35A in association with the original NC program in order to repeat the same machining. At this time, the axis control data for the entire series of machining operations can be saved and stored in the axis control data storage means 35F. However, since the NC program is stored in the NC program storage means 35A, it is not particularly necessary to save and save it except for the trouble of recalculating the axis control data when machining again.

  The axis control data output unit 37 sequentially transmits the axis control data A stored in the axis control data storage unit 35E to the axis control data receiving unit 44 of the processing machine 4.

  The command value calculation unit 45 of the processing machine 4 generates an actual command value according to the speed of the axis control data A received by the axis control data reception unit 44, and outputs the actual command value to the motor control units 46a, 46b, and 46c of each axis. Further, the motor control units 46a, 46b, 46c output the actual command values to the linear motors 48a, 48b, 48c as drive currents through the linear amplifiers 47a, 47b, 47c. As shown in FIG. 7, the speed change is recorded in the axis control data A at intervals of Δt, the moving speed in the X-axis direction is Vxi at time Ti, and the moving speed in the X-axis direction is Vx at time Ti + 1. If (i + 1), the movement signal is a movement signal between time Ti and time Ti + 1, and a movement signal that changes the movement speed in the X-axis direction from Vxi to Vx (i + 1) is sent to the motor controller 46a. Is output to the linear amplifier 47a. Similarly, when the movement speed in the Y-axis direction is Vyi at time Ti and the movement speed in the Y-axis direction is Vy (i + 1) at time Ti + 1, the movement signal is from time Ti to time Ti + 1. , The motor control unit 46b outputs a movement signal such that the movement speed in the Y-axis direction changes from Vyi to Vy (i + 1) to the linear amplifier 47b. By changing the movement speed of each axis in this way, the machining position can be moved from the start point position P1 to the end point position P2 along the division locus l.

  Here, in the machining system 1 of the present invention, an example of a flow of operations and processes for visually confirming the finished shape after machining a workpiece and changing the speed of the axis control data A of the defective part visually confirmed. Will be described with reference to the flowchart of FIG.

  The operator operates the CAM device 2 or the processing control device 3 and is stored in the storage device of the CAM device 2, or is stored in an external storage device such as a server connected via a LAN. A program is selected (S1). Then, the selected NC program is stored in the NC program storage means 35A of the machining control device 3 through the input / output unit 33 of the machining control device 3. When the CAM device 2 has the function of the machining data calculation device, the operator uses the GUI to select the machining machine 4 used for machining so that the remote operation can be performed. At this time, in the CAM device 2, the parameter corresponding to the processing machine 4 selected from the parameter storage unit 22 becomes the default value.

  Next, when the operator selects a desired NC program to be machined from the NC program file stored in the NC program storage means 35A of the axis control data calculation unit 35 of the machining control device 3, the axis control is performed. The NC program decoding means 35B of the data calculation unit 35 reads the NC program selected from the NC program storage means 35A, analyzes it in the order programmed for each program block, and generates NC data. Then, the NC program decoding unit 35B sends NC data including at least the relative movement and the shape of the tool path, for example, NC data including the G code, to the tool path generation unit 35C. Further, the NC program decoding unit 35B stores data of a plurality of types of parameters that can be obtained from the NC data in the parameter storage unit 34 (S2).

  The tool path generation unit 35C acquires NC data required for generating axis control data from the NC program decoding unit 35B, and forms a shape defined by the NC program based on the acquired NC data into a plurality of parametric curves. To generate a tool path. The tool path generation unit 35C stores the generated tool path data in the tool path storage unit 35D (S3).

  The axis control data generating means 35E is a calculation process already described, and a feed speed (machining speed) F specified by the NC program, and a parametric curve that is a tool path stored in the tool path storage means 35D Using the parameters corresponding to the selected processing machine 4, the movement command originally defined in the NC program is converted into the axis control data A, and the generated axis control data A is stored as a file. The information is stored in the means 35F (S4). Subsequently, the axis control data calculation unit 35 of the machining control device 3 sequentially receives the axis control data A stored in the axis control data storage unit 35F from the axis control data output unit 37 to the axis control data reception unit 44 of the processing machine 4. And the workpiece is test processed by the processing machine 4 (S5).

  When the processing is completed by the processing machine 4, the operator visually confirms the finished shape of the workpiece (S6). If there is no problem in the finished shape (S6-OK), the operation is finished, but if there is a problem in the finished shape (S6-NG), a defective part is specified. Immediately after the end of machining, the NC program used in machining remains selected in the machining control device 3, so that the operator operates the machining control device 3 to display the contents of the NC program on the display unit 31. Find the program block that caused the problem to appear and identify the problem. Alternatively, the tool path is drawn on the display unit 31 using the axis control data stored in the axis control data storage means 35F, and the relative movement of the tool is simulated to identify the defective part on the machining tool path. The following shows the process of identifying a defect location by simulation.

  First, when the operator executes a simulation, the drawing display unit 35G reads the axis control data A file corresponding to the selected NC program from the axis control data storage unit 35F. The drawing display means 35G generates drawing data representing the machining tool path in accordance with the read axis control data A, and the machining tool path is generated on the display screen of the display unit 31 through the simulation unit 36 using the generated drawing data. (S7).

  The operator compares the finished shape of the workpiece with the machining tool trajectory displayed on the display screen, and identifies the portion where the defect appears. Using the mouse or the like, the operator surrounds the portion where the defect appears on the machining tool trajectory displayed on the display screen (see FIG. 8), and designates the designated section (S8). Further, the operator inputs an appropriate partial deceleration rate according to the state of the malfunction (S9). At this time, since the partial deceleration rate is an override value, it is not necessary for the operator to strictly input the real value of the parameter, and an appropriate partial deceleration rate that is sensuously appropriate can be given.

  The control data changing unit 35I of the axis control data calculating unit 35 of the machining control device 3 receives the specified section set by the operator through the specified section receiving unit 35H and also receives the partial deceleration rate from the deceleration rate receiving unit 35J. The axis control data changing means 35I specifies the range of the axis control data corresponding to the specified section in the axis control data A that is the origin of the drawing data of the machining tool trajectory displayed on the simulated display screen of the display unit 31. Further, the axis control data A is changed according to the input partial deceleration rate, and the changed axis control data A is recorded in a file (S10). At this time, the process of changing the axis control data in accordance with the partial deceleration rate in the axis control data changing means 35I is sequentially in the specified section from the start position Ps, speed vs, time ts, and acceleration data of the specified section. At each time tsn corresponding to a predetermined time interval, the speed Vsni is recalculated according to the given partial deceleration rate, and even if the speed changes from the start point Ps to the position Ps + n and the acceleration to the speed Vsni. By specifying the time ti at which the position Psn does not change, the speed change H2 (t) is obtained, but since it has already been described, the description of the specific process is omitted here.

  The axis control data changing unit 35I generates partial axis control data in the designated section based on the calculated speed change H2 (t), and writes the axis control data in the designated section to the original axis control data of the entire machining. Axis control data is regenerated with (However, it is not always necessary to incorporate the partially corrected axis control data into the original axis control data). Then, the machining machine 4 is operated according to the changed axis control data A to perform test machining (S5), and the finished shape is confirmed again (S6). The operator repeats the above operations until no defect is confirmed in the finished shape by visual inspection.

  Moreover, although the case where the speed of each axis is recorded at a certain time interval has been described in the axis control data A, the change in speed may be recorded.

  In the above description, the case where the axis control data A in which the speed change is recorded at a constant time interval is output to the drive unit has been described. The speed of each axis may be changed according to the mathematical formula received by the drive unit.

  In the above-described embodiment, the case where the axis control data A is changed by the machining control device 3 has been described. However, the CAM device 2 is provided with the specified section receiving means 35H and the axis control data changing means 35I described above. Then, the axis control data A may be changed by setting a designated section for changing the machining speed of the machining tool trajectory displayed by the simulation unit 36 using a stylus pen or the like.

  As described above in detail, according to the present invention, it is possible to reduce the machining speed only for necessary portions without reducing the overall machining efficiency.

  By the way, although rare, the machining efficiency may be improved if the speed is partially increased from the original speed. Specifically, for example, when the operator sets the maximum acceleration with reference to the speed distribution or speed change based on the axis control data, it is set to be considerably lower than the maximum acceleration limit value that can be set. There is a possibility that the feed rate may become too low partially.

  When it is necessary to operate the speed of the specified section higher than the original speed, partial deceleration is performed at a ratio greater than the override value of 100% within the range that does not exceed the maximum acceleration inherent to the machine below the set maximum feed speed. What is necessary is just to set a rate. In the present invention, for convenience of explanation, the ratio when the speed becomes higher than the original speed is also referred to as “partial deceleration rate”.

  When changing the speed of the designated section so as to be larger than the original speed, the axis control data changing means 35I uses the start point position Ps, the speed Vs, and the time ts in the same way as when changing the speed to be smaller. Then, the speed Vsni recalculated according to the partial deceleration rate k given through the deceleration rate receiving means 35J is obtained for each time tns corresponding to a predetermined time interval in the designated section. The relationship between the speed before the change and the speed after the change can be considered that the change curve before the change and the change curve after the change in FIG. Therefore, if the partial deceleration rate changes, the time required to pass through the specified section is shortened, but the speed change can be adjusted so that the tool trajectory in the specified section does not change even if the partial deceleration rate changes. it can.

DESCRIPTION OF SYMBOLS 1 Processing system 2 CAM apparatus 3 Processing control apparatus 4 Processing machine 5 Network 31 Display part 32 Operation part 33 Input / output part 34 Parameter storage part 35 Axis control data calculation part 35A NC program storage means 35B NC program decoding means 35C Tool locus generation means 35D Tool trajectory storage means 35E Axis control data generation means 35F Axis control data storage means 35G Drawing display means 35H Designated section acceptance means 35I Axis control data change means 35J Deceleration rate acceptance means 35E-1 Division trajectory calculation means 35E-2 Axis control data Calculation means 36 Simulation unit 37 Axis control data output unit 38 Input / output unit 41 Main shaft 42A Table 42B Saddle 43 Drive unit 44 Axis control data reception unit 45 Command value calculation unit 46 Motor control unit 47 Linear amplifier 48 Linear motor

Claims (5)

In order to move a tool by controlling a plurality of control axes at a specified machining speed along a predetermined tool locus, the division locus corresponding to each divided locus of the plurality of divided loci obtained by dividing the tool locus Axis control data storage means for storing a plurality of axis control data representing a speed change with respect to time of the position of at least one point of each of the control axes of the tool,
In accordance with the plurality of axis control data, a drawing display unit that generates drawing data representing a machining tool path, and displays the machining tool path on a display screen of a display device using the generated drawing data;
A designated section receiving means for receiving an input of a designated section for changing the machining speed designated on the machining tool trajectory displayed on the display screen;
The original speed at which the speed at each position in the designated section is determined by the axis control data by extending or shortening the passing time for the tool to pass through the designated section without changing the machining tool trajectory corresponding to the designated section. Axis control data changing means for changing the axis control data corresponding to the specified section,
A machining data arithmetic device comprising:   The axis control data is obtained by analyzing the NC code specified by the NC program and the tool path obtained from the coordinate value of each axis and the machining speed specified by the NC program, and converting it into the axis control data. The machining data calculation device according to claim 1, wherein the machining data calculation device is provided. A deceleration rate receiving means for receiving a rate of deceleration with respect to the current machining speed of the specified section in the specified section;
The machining data according to claim 1 or 2, wherein the axis control data changing means changes the axis control data so that the speed of the designated section becomes a speed corresponding to the rate of deceleration. Arithmetic unit.   4. The specified section receiving means receives a machining tool trajectory displayed within a range surrounded by a predetermined shape on the display screen as the specified section. The processing data calculator described. Computer
In order to move a tool by controlling a plurality of control axes at a specified machining speed along a predetermined tool path, the divided path corresponding to each of the divided paths of the plurality of divided paths divided from the tool path Axis control data storage means for storing a plurality of axis control data representing speed changes with respect to time of each axis position of the starting point and each control axis of the tool;
In accordance with the plurality of axis control data, a drawing display unit that generates drawing data representing a machining tool path, and displays the machining tool path on a display screen of a display device using the generated drawing data;
A designated section receiving means for receiving an input of a designated section for changing the machining speed designated on the machining tool trajectory displayed on the display screen;
The original speed at which the speed at each position in the designated section is determined by the axis control data by extending or shortening the passing time for the tool to pass through the designated section without changing the machining tool trajectory corresponding to the designated section. A machining data calculation program for functioning as axis control data changing means for changing the axis control data corresponding to the specified section so as to change the axis.