JP2014010678A - Process instruction conversion program, storage medium, and process instruction conversion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow for a treatment for reducing an error in processing a shape generated by a post-interpolated acceleration/deceleration processing in a short period while lessening work loads in a cost aspect and a work aspect.SOLUTION: A processing instruction conversion device 2 derives a reference machine shaft path on the basis of a numerical control (NC) program, derives a post-converted machine shaft path by performing a specific conversion process to the derived reference machine spindle path, converts the post-converted machine spindle path into a post-converted NC program and includes a conversion part 4 that outputs the post-converted NC program to a numerical control device 200 such that the numerical control device 200 calculates a machine spindle path on the basis of the post-converted NC program. As the specific conversion process, the conversion part 4 performs an arithmetic process of calculating a correction amount equivalent to an approximation value of an error between a machine spindle path obtained from a transfer pulse after a post-interpolated acceleration/deceleration process is performed and the reference machine spindle path and calculating the post-converted machine spindle path having the reference machine spindle path corrected in a direction in which the error is cancelled out by the calculated correction amount.

Description

  The present invention relates to a machining command conversion program, a storage medium, and a machining command conversion device used for various machine tools.

  Conventionally, in various machine tools, a workpiece is processed by numerically controlling a transfer device that transfers a workpiece and a tool for processing the workpiece according to a processing command (NC program). Patent Document 1 below discloses a numerical control device that performs numerical control of such a transfer device.

  In the numerical control device disclosed in Patent Document 1, a tool path representing a change in the position coordinate of a tool in a coordinate system fixed on a workpiece as a function of a parameter is obtained from a machining program, and the transfer path of the transfer device is determined from the tool path. A drive axis path for each drive axis is obtained, and a command pulse indicating a movement amount for each reference unit time (cycle time) in each drive axis is obtained based on the obtained drive axis path for each drive axis, and obtained. Each transfer device is controlled by outputting the command pulse to the motor of the transfer device corresponding to each drive shaft. In this numerical controller, block smooth interpolation and corner smooth interpolation are performed on the drive axis path, and the command pulse is obtained by pulse interpolation from the drive axis path after the smooth interpolation. The block smooth interpolation interpolates a drive axis path formed by connecting a large number of command points with straight lines into a smooth curve, and the corner smooth interpolation is positioned before and after a predetermined command point in the drive axis path. This corner portion is interpolated so that a corner portion where the amount of change in coordinates changes greatly is a corner that smoothly turns.

  However, in the technique described in Patent Document 1, in the case where unexpected abnormality data (noise or the like) in which the change amount of the position coordinates repeatedly changes suddenly at a minute interval is included in the drive axis path, It is difficult to smoothly interpolate the abnormal data portion. When such abnormal data is included in the drive shaft path and the transfer device is controlled according to the drive shaft path, the operation of the transfer device changes suddenly at the portion corresponding to the abnormal data, and the processing machine A mechanical shock occurs. For this reason, it is an important issue to correct the abnormal data in the drive shaft path.

  Therefore, Patent Document 2 below shows a numerical control device that can solve such a problem.

  In the numerical control device disclosed in Patent Document 2, post-interpolation acceleration / deceleration processing that can correct abnormal data that causes mechanical shock is performed. Specifically, in this numerical control device, a movement command to be output to the servo motor for each drive axis is obtained by performing interpolation processing (pulse interpolation) on a path obtained by converting the machining program into an execution format, and the obtained movement command Acceleration / deceleration processing is performed on According to this post-interpolation acceleration / deceleration processing, even if a portion corresponding to abnormal data in the drive axis path is included in the movement command obtained by pulse interpolation, a portion corresponding to the abnormal data in the movement command And the occurrence of mechanical shock can be suppressed.

JP 2008-225825 A JP 2010-140312 A

  However, when the post-interpolation acceleration / deceleration process is performed, there is a drawback that an error in the workpiece machining shape occurs. Specifically, in the post-interpolation acceleration / deceleration in Patent Document 2, the portion to which the acceleration / deceleration processing is applied is not limited in the movement command, and therefore the acceleration / deceleration processing is a portion other than the portion corresponding to the abnormal data in the movement command. It can also be applied to. For example, when the acceleration / deceleration processing is performed on a part of the movement command that corresponds to a part that actually instructs acceleration or deceleration of the tool or workpiece in the machining program, the tool or workpiece to be executed based on that part is processed. The acceleration or deceleration is alleviated, and as a result, an error occurs with respect to the machining shape indicated by the machining program in the shape of the actually machined workpiece. For this reason, it is required to reduce the machining shape error associated with such post-interpolation acceleration / deceleration processing. However, machine tools incorporating a numerical control device that performs acceleration / deceleration processing after interpolation are already used in many production sites. For example, the entire control program used in the numerical control device can Replacing with a new control program that has been modified to reduce errors is burdensome in terms of cost and work. Further, if an attempt is made to modify the control program currently used to reduce the error, such modification work is very difficult and the machine tool is stopped for a long period of time. As a result, the production loss is enormous.

  The present invention has been made in order to solve the above-mentioned problems, and it is possible to reduce the work shape error caused by the post-interpolation acceleration / deceleration processing in a short period of time while reducing the cost and work load. It is to be able to take measures for reduction.

In order to achieve the above object, a machining command conversion program according to the present invention comprises a plurality of transfer devices for transferring a workpiece or a tool for machining the workpiece to the workpiece to machine the workpiece, Each of the transfer devices includes a support for supporting the object, and an arithmetic process provided in a machine tool having a transfer unit that transfers the object by transferring the support in a specific machine axis direction. A machine axis path indicating a position at which each support body is to be transferred at each time of a predetermined cycle time interval in each corresponding machine axis direction, and each machine axis is determined from the determined machine axis path A transfer pulse indicating the transfer amount of each support in the block between each time in the direction is obtained, and the obtained transfer pulse for each machine axis direction is associated with the machine axis direction. The post-interpolation acceleration / deceleration processing is calculated by performing post-interpolation acceleration / deceleration processing that distributes and accumulates within the distribution interval having a specific time constant interval width set for the post-interpolation acceleration / deceleration. The present invention is applied to an arithmetic processing device configured to be able to exchange data with a numerical control device that controls transfer of the support by the transfer unit of each transfer device in accordance with a transfer pulse after processing. Machining command conversion program
Each of the supports for moving the tool according to the movement trajectory based on a machining command that represents the movement trajectory of the tool at the time of machining the workpiece by coordinates of the command points at the respective times with respect to the machine axis directions. A path deriving step for deriving a reference machine axis path indicating a position in each machine axis direction to which the body should be transferred at each time, and a conversion process specific to the reference machine axis path for each derived machine axis direction. A path conversion step for deriving a converted machine axis path for each of the machine axis directions, and converting the converted machine axis path for each of the machine axis directions into a converted machining command representing the form of the machining command Machining command conversion step, and the numerical control device so that the numerical control device obtains the machine axis path for each machine axis direction based on the post-conversion machining command An output step of outputting the post-conversion machining command is executed by the arithmetic processing unit, and in the path conversion step, the post-interpolation acceleration / deceleration processing in each machine axis direction is performed as the specific conversion processing. A correction amount corresponding to an approximate value of an error between the machine axis path obtained from the pulse and the reference machine axis path corresponding to the machine axis direction is calculated for each machine axis direction, and each of the calculated machine axes Causing the arithmetic processing unit to execute arithmetic processing for calculating the converted mechanical axis path obtained by correcting the reference mechanical axis path in each of the mechanical axis directions in a direction in which the error is canceled by a correction amount for each direction.

  In this machining command conversion program, it corresponds to an approximate value of an error between a machine axis path obtained from a transfer pulse after post-interpolation acceleration / deceleration processing for each machine axis direction and the reference machine axis path for the corresponding machine axis direction. A post-conversion machine axis path obtained by calculating a correction amount for each machine axis direction and correcting the reference machine axis path for each machine axis direction in a direction that cancels the error with the calculated correction amount for each machine axis direction. Calculation processing, processing for converting the converted machine axis path for each machine axis direction calculated by the calculation processing into the converted machining command, and a numerical control device based on the converted machining command for each machine In order to cause the arithmetic processing unit to execute a process of outputting the post-conversion machining command to the numerical control device so as to obtain a machine axis path in the axial direction, the numerical control device includes: Can be input in advance anticipation is converted machining command corrected for each machine axis in a direction to cancel the error of the error of each machine axis direction each time due after deceleration process between. For this reason, when the numerical control device performs post-interpolation acceleration / deceleration processing, errors in all machine axis directions caused by the post-interpolation acceleration / deceleration processing can be made minute. As a result, post-interpolation acceleration / deceleration processing can be performed. It is possible to reduce an error in the work shape of the workpiece that occurs with the processing. Furthermore, the machining command conversion program can reduce errors generated by post-interpolation acceleration / deceleration processing only by being applied to an arithmetic processing device configured to be able to exchange data with a numerical control device. Therefore, the control program currently used in the numerical control device of the existing machine tool can be used as it is. Therefore, compared to the case where the entire control program used in the numerical control device is replaced or the control program is modified, the burden on the cost and work is reduced, and in a short period of time. Thus, it is possible to implement a measure for reducing an error caused by the post-interpolation acceleration / deceleration processing.

  In the machining command conversion program, in the arithmetic processing to be executed by the arithmetic processing unit as the specific conversion processing, processing corresponding to the post-interpolation acceleration / deceleration processing is performed on the reference mechanical axis path for each of the mechanical axis directions, respectively. A reference error, which is an error between the machine axis path for each machine axis direction after the processing and the reference machine axis path corresponding to the machine axis direction, is calculated for each machine axis direction, and the calculation is performed. In the process corresponding to the post-interpolation acceleration / deceleration process, the reference error in each machine axis direction is set as the correction amount in each machine axis direction. A speed function that is a first-order differential function of the reference mechanical axis path at each time T in a section extending from t−a to t + a is defined as P ′ (a), which is a half value of the set time constant. ), And the numerical control device represents a distribution format for distributing the transfer pulse, and a distribution function satisfying the following equation (1) is f (T), a post-interpolation acceleration / deceleration processing equivalent to The post-interpolation acceleration / deceleration process is performed by calculating a speed function Q ′ (t), which is a linear differential function of the mechanical axis path, based on the following equation (2) and integrating the calculated speed function Q ′ (t). It is preferable to cause the arithmetic processing unit to execute a process for calculating a machine axis path Q (t) after the process corresponding to.

  According to this configuration, a process corresponding to the post-interpolation acceleration / deceleration process executed by the arithmetic processing device can be specifically configured. Further, according to this configuration, when calculating an error between the machine axis path Q (t) after the process corresponding to the post-interpolation acceleration / deceleration process and the reference machine axis path, the machine axis path Q (t) Phase error caused by the distribution format of the speed of the reference machine axis path at the time of processing equivalent to the post-interpolation acceleration / deceleration process without associating the times of the points to be subtracted from each other with the reference machine axis path Can be excluded from an error between the machine axis path Q (t) and the reference machine axis path. Specifically, suppose that the speed at each time in a section of the reference machine axis path is divided into distribution sections each having a section width corresponding to the time constant after that time, and each distributed value is integrated. When calculating the machine axis path after performing processing equivalent to post-interpolation acceleration / deceleration processing according to a calculation formula that further integrates the calculated speed function, add post-interpolation. The time in the machine axis path after the process corresponding to the deceleration process deviates from each time in the reference machine axis path due to the speed distribution format of the reference machine axis path. For this reason, when the error is obtained by subtracting the reference machine axis path from the machine axis path after the processing corresponding to the post-interpolation acceleration / deceleration processing without considering the time lag, the phase error is included in the error. It will be. In such a case, if the phase error element is to be eliminated, the correspondence for eliminating the time lag between the machine axis path after the processing corresponding to the post-interpolation acceleration / deceleration processing and the reference machine axis path. After performing (time adjustment), it is necessary to obtain an error between the machine axis path after the process and the reference machine axis path, and the process of associating is complicated. On the other hand, in the present configuration, the speed function P ′ (T) at each time T in the section from t−a to t + a is changed around the time T by the distribution function satisfying the above equation (1). Therefore, the time is not shifted later due to the speed distribution format of the reference mechanical axis path as described above. Therefore, the speed function Q ′ (t) is calculated by integrating the speed distribution value P ′ (T) · f (t−T) of the reference mechanical axis path distributed in the distribution section according to the above equation (2). Further, when the machine axis path Q (t) after processing corresponding to the post-interpolation acceleration / deceleration processing is calculated by integrating the calculated speed function Q ′ (t), in the section instructing transfer at a constant speed, The coordinate values at the same time t match between the machine axis path Q (t) after processing and the reference machine axis path. As a result, when calculating the error between the processed machine axis path Q (t) and the reference machine axis path, the time between points that are subtracted from each other between the machine axis path Q (t) and the reference machine axis path. Therefore, it is possible to eliminate the phase error element resulting from the speed distribution format of the reference machine axis path from the error.

  In the machining command conversion program, the plurality of time constants set for the respective machine axis directions include time constants having values different from the time constants for the other machine axis directions. In the post-interpolation acceleration / deceleration processing, when the transfer pulse of each block in each machine axis direction is distributed, the section width corresponding to the time constant set in the machine axis direction to be distributed is When distributing the transfer pulse in the distribution section extending from the end point of the block to the subsequent distribution section, the machining command conversion step temporarily converts the converted machine axis path into a temporary conversion processing command expressed in the form of the machining command. A conversion step and an adjustment step for adjusting the coordinates of each command point constituting the temporary conversion machining command in the respective machine axis directions to obtain the post-conversion machining command. In the adjustment step, in the post-interpolation acceleration / deceleration process, the transfer pulse in each machine axis direction is distributed in the distribution section according to the time constant for each machine axis direction. Of each of the command points of the provisional conversion machining command so that the difference in the time delay between the transfer pulses after the post-interpolation acceleration / deceleration processing in each of the machine axis directions generated by the distribution is offset. It is preferable to cause the arithmetic processing unit to execute processing for adjusting coordinates in the respective machine axis directions.

  According to this configuration, it is possible to eliminate the difference in time delay between the machine axis directions that occurs during the acceleration / deceleration processing after interpolation due to the difference in time constant for each machine axis direction, As a result, it is possible to prevent the occurrence of a phase error between the machine axis directions due to the difference in time delay between the machine axis directions.

  A storage medium according to the present invention is a storage medium in which the machining command conversion program is stored, and the processing command conversion program stored in the storage medium is introduced into the arithmetic processing device in order to introduce the processing command conversion program. Combined.

  According to this configuration, the machining command conversion program can be introduced into the arithmetic processing device simply by coupling the storage medium to the arithmetic processing device. Can be easily implemented.

  The machining command conversion device according to the present invention includes a plurality of transfer devices for transferring a workpiece or a tool for machining the workpiece to the workpiece to process the workpiece, and each of the transfer devices includes the object. Are provided in machine tools each having a support for supporting the object and a transfer unit for transferring the object by transferring the support in a specific machine axis direction. A machine axis path indicating a position to be transferred at each time of a predetermined cycle time interval in the machine axis direction is obtained, and each support in the block between each time in the machine axis direction is obtained from the obtained machine axis path. A distribution section having a specific time constant section width set for the corresponding machine axis direction is determined for each transfer pulse for each machine axis direction. The post-interpolation acceleration / deceleration processing transfer pulse is obtained by performing post-interpolation acceleration / deceleration processing that is distributed and integrated to the transfer unit. A machining command conversion device applied to a numerical control device for controlling the transfer of the support according to the above, wherein the movement trajectory of the tool at the time of machining the workpiece is the direction of each machine axis of the command point at each time A reference machine axis path indicating a position in each machine axis direction to which each support should be transferred at each time in order to move the tool according to the movement trajectory based on a machining command represented by the coordinates of The converted machine axis path for each machine axis direction is derived by performing a specific conversion process on the reference machine axis path for each derived machine axis direction, and each of the derived machine axes The converted machine axis path for the direction is converted into a converted machining command that is expressed in the form of the machining command, and the numerical control device converts the machine axis path for each machine axis direction based on the converted machining command. A conversion unit that outputs the post-conversion machining command to the numerical control device so as to obtain the transfer pulse after the post-interpolation acceleration / deceleration processing in each machine axis direction as the specific conversion processing; A correction amount corresponding to an approximate value of an error between the machine axis path obtained from the reference machine axis path with respect to the corresponding machine axis direction is calculated for each machine axis direction, and each calculated machine axis direction is calculated. An arithmetic process is performed to calculate the converted machine axis path obtained by correcting the reference machine axis path in each of the machine axis directions in a direction that cancels out the error with each correction amount.

  In this machining command conversion device, for the same reason as the above-described machining command conversion program, the work shape error of the workpiece caused by the post-interpolation acceleration / deceleration processing is reduced in a short period of time while reducing the cost and work load. Treatment for reduction can be performed.

  In the machining command conversion device, the conversion unit performs a process corresponding to the post-interpolation acceleration / deceleration process on the reference machine axis path in each machine axis direction in the calculation process performed as the specific conversion process. A reference error, which is an error between the machine axis path for each machine axis direction after the processing and the reference machine axis path corresponding to the machine axis direction, is calculated for each machine axis direction, and the calculation is performed. In the process corresponding to the post-interpolation acceleration / deceleration process, the reference error in each machine axis direction is set as the correction amount in each machine axis direction. A value that is half of the set time constant is a, and a speed function that is a first-order differential function of the reference mechanical axis path at each time T in a section from t−a to t + a is P ′ (T). The machine axis path after processing corresponding to the post-interpolation acceleration / deceleration processing when the numerical control device represents the distribution format for distributing each transfer pulse and the distribution function satisfying the following equation (3) is f (T) Is calculated based on the following equation (4), and the calculated speed function Q ′ (t) is integrated to correspond to the post-interpolation acceleration / deceleration processing. It is preferable to perform a calculation process for calculating the machine axis path Q (t) after the process.

  According to this configuration, the machine axis after processing corresponding to the post-interpolation acceleration / deceleration processing for the same reason as the machining command conversion program that causes the arithmetic processing device to execute the arithmetic processing using the equations (1) and (2). When calculating the error between the path Q (t) and the reference machine axis path, the time of the points to be subtracted between the machine axis path Q (t) and the reference machine axis path is not correlated. In addition, the phase error element caused by the speed distribution format of the reference machine axis path at the time of processing corresponding to the post-interpolation acceleration / deceleration process is excluded from the error between the machine axis path Q (t) and the reference machine axis path. Can do.

  In the machining command conversion device, the plurality of time constants set for the respective machine axis directions include time constants having different values from the time constants for the other machine axis directions. In the post-interpolation acceleration / deceleration processing, when the transfer pulse of each block in each machine axis direction is distributed, the section width corresponding to the time constant set in the machine axis direction to be distributed is In the case of distributing the transfer pulse in the distribution section extending from the end point of the block, the conversion unit is configured to convert the converted machine axis path in the respective machine axis directions into the converted machining command. The converted machine axis path is once converted into a temporary conversion machining command expressed in the form of the machining command, and then each command point constituting the temporary conversion machining command is connected to each machine axis direction. When the coordinates of the command points constituting the temporary conversion processing command are adjusted, the conversion unit is configured to adjust the direction of each machine axis in the post-interpolation acceleration / deceleration processing. The time between the transfer pulses after the post-interpolation acceleration / deceleration processing for each machine axis direction generated by distributing the transfer pulses in each machine axis direction to the distribution section corresponding to each time constant It is preferable to adjust the coordinates of the command points of the provisional conversion machining command with respect to the machine axis directions so that the difference in delay is offset.

  According to this configuration, it is possible to eliminate the difference in time delay between the machine axis directions that occurs during the acceleration / deceleration processing after interpolation due to the difference in time constant for each machine axis direction, As a result, it is possible to prevent the occurrence of a phase error between the machine axis directions due to the difference in time delay between the machine axis directions.

  As described above, according to the present invention, it is possible to reduce the cost and work load, and in a short period of time, take measures for reducing errors in the workpiece machining shape that accompany the post-interpolation acceleration / deceleration processing. It can be carried out.

1 is a perspective view illustrating an example of a machine tool to which a machining command conversion program and a machining command conversion device according to an embodiment of the present invention are applied. 1 is a functional block diagram of a machining command conversion device and a numerical control device to which the machining command conversion device according to an embodiment of the present invention is applied. It is a figure which shows the locus | trajectory of the target object which the reference | standard machine axis path (command path) by an example instruct | indicates. When the reference machine axis path (command path) has a shape as shown in FIG. 3, the reference machine axis path, the machine axis path obtained from the post-interpolation acceleration / deceleration processing transfer pulse, and the conversion unit addition It is a schematic diagram which shows the image of the relative relationship with the mechanical axis path (post-conversion mechanical axis path) after a deceleration process. It is a flowchart which shows the conversion process process of the NC program by the process command converter of one Embodiment of this invention. It is a flowchart which shows the content of the subroutine of step S6 which derives | leads-out the machine axis path | pass after conversion in FIG. In the conversion part acceleration / deceleration process in one Embodiment of this invention, it is a figure which shows the image of distribution when the area width of the block used as the distribution object of the speed function of a reference | standard machine shaft path is larger than a time constant. In the conversion part acceleration / deceleration process in one Embodiment of this invention, it is a figure which shows the image of distribution when the area width of the block used as the distribution object of the speed function of a reference | standard machine shaft path is smaller than a time constant. In the conversion part acceleration / deceleration process in one Embodiment of this invention, it is a figure which shows the image of distribution when the area width of the block used as the distribution object of the speed function of a reference | standard machine shaft path is smaller than a time constant. It is a figure which shows the image of distribution when the section width of the block used as the distribution object of the speed function of a reference | standard machine shaft path is larger than a time constant in the conversion part acceleration / deceleration process in other embodiment of this invention. It is a figure which shows the image of distribution when the section width of the block used as the distribution object of the speed function of a reference | standard mechanical axis path is smaller than a time constant in the conversion part acceleration / deceleration process in other embodiment of this invention. It is a figure which shows the image of distribution when the section width of the block used as the distribution object of the speed function of a reference | standard mechanical axis path is smaller than a time constant in the conversion part acceleration / deceleration process in other embodiment of this invention. It is a functional block diagram of the arithmetic processing apparatus and storage medium by the modification of one Embodiment of this invention, and the numerical control apparatus to which they are applied.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  First, an example of a machine tool to which a machining command conversion program and a machining command conversion device according to an embodiment of the present invention are applied will be described with reference to FIG.

  This machine tool is a machine tool provided with a so-called portal frame, and cuts a workpiece 500, which is a workpiece set on a table 102a, with a tool 104 that moves on the workpiece 500. The machine tool includes a workpiece transfer device 102, a tool 104, a spindle head 106, a swing device 108, a rotation device 110, a first vertical transfer device 112, a horizontal transfer device 114, and a second vertical transfer device. 116. The workpiece transfer device 102, the swinging device 108, the rotation device 110, the first vertical transfer device 112, the horizontal transfer device 114, and the second vertical transfer device 116 use the workpiece 500 or the tool 104 as the target object. The workpiece 500 is transferred for processing, and each is included in the concept of the “transfer device” of the present invention.

  The workpiece transfer device 102 is a table 102a for supporting the workpiece 500 from below, and a workpiece placed on the table 102a by transferring the table 102a in the X-axis direction extending in a specific direction in the horizontal plane. And a table transfer section 102b for transferring to the table. The table transfer unit 102b has a servo motor 102c (see FIG. 2), and is operated by power generated by the servo motor 102c to transfer the table 102a.

  The tool 104 is for cutting the workpiece 500 and is held by the spindle head 106. The spindle head 106 rotates the held tool 104 around its axis. When the tool 104 rotated by the spindle head 106 contacts the workpiece 500, the workpiece 500 is processed.

  The oscillating device 108 oscillates the tool 104 in the A-axis direction around an axis extending in the horizontal direction parallel to the upper surface of the table 102a. The rocking device 108 includes a rocking support 108a and a rocking support transporting part 108b. The swing support body 108a supports the spindle head 106 and is supported by the rotation device 110 so as to be swingable in the A-axis direction. The swing support body transfer unit 108b swings the swing support body 108a in the A-axis direction to swing the spindle head 106 and the tool 104 together with the swing support body 108a in the A-axis direction. The swing support body transfer part 108b has a servo motor 108c (see FIG. 2), and is operated by the power generated by the servo motor 108c to swing the swing support body 108a.

  The rotation device 110 includes the tool 104, the spindle head 106, and the oscillation in the C-axis direction, which is a rotation direction about an axis extending in a direction perpendicular to an axis that is a center of oscillation of the tool 104 by the oscillation device 108. The moving device 108 is rotated. The rotation device 110 includes a rotation support member 110a and a rotation support member transfer unit 110b. The rotation support member 110a supports the swing device 108 and is supported by the first vertical transfer device 112 so as to be rotatable in the C-axis direction. The rotation support body transfer unit 110b rotates the rotation support body 110a in the C-axis direction to rotate the swing device 108, the spindle head 106, and the tool 104 in the C-axis direction together with the rotation support body 110a. Let The rotation support body transfer part 110b has a servo motor 110c (see FIG. 2), and is operated by the power generated by the servo motor 110c to rotate the rotation support body 110a.

  The first vertical transfer device 112 transfers the tool 104, the spindle head 106, the swing device 108, and the rotation device 110 along the Z axis extending in the vertical direction. The first vertical transfer device 112 includes a ram 112a and a ram transfer unit 112b. The ram 112a is disposed above the table 102a, supports the rotating device 110, and is supported by the horizontal transfer device 114 so as to be movable in the Z-axis direction. The ram transfer unit 112b transfers the ram 112a in the Z-axis direction, thereby transferring the rotating device 110, the swinging device 108, the spindle head 106, and the tool 104 together with the ram 112a in the Z-axis direction. The ram transfer unit 112b has a servo motor 112c (see FIG. 2), and is operated by power generated by the servo motor 112c to transfer the ram 112a.

  The horizontal transfer device 114 transfers the tool 104, the spindle head 106, the swing device 108, the rotation device 110, and the first vertical transfer device 112 along the Y axis that is orthogonal to both the X axis and the Z axis. The horizontal transfer device 114 includes a saddle 114a and a saddle transfer unit 114b. The saddle 114a supports the first vertical transfer device 112 and is supported by the cross rail 116a so as to be movable in the Y-axis direction. The saddle transfer unit 114b has a servo motor 114c, and is operated by power generated by the servo motor 114c to transfer the saddle 114a.

  The second vertical transfer device 116 includes a tool 104, a spindle head 106, a swing device 108, a rotation device 110, a first first vertical transfer device 112, and a horizontal transfer device 114 along a W axis parallel to the Z axis. Transport. The second vertical transfer device 116 includes a cross rail 116a and a cross rail transfer unit 116b. The cross rail 116a supports the horizontal transfer device 114 and is movable in the W-axis direction. The cross rail transfer unit 116b has a servo motor 116c, which is operated by power generated by the servo motor 116c and transfers the cross rail 116a.

  The X-axis, A-axis, C-axis, Z-axis, Y-axis, and W-axis are each included in the concept of “mechanical axis” of the present invention. Further, the table 102a, the swing support 108a, the rotation support 110a, the ram 112a, the saddle 114a, and the cross rail 116a are each included in the concept of the “support” of the present invention. Hereinafter, for the sake of simplification, the table 102a, the swing support 108a, the rotation support 110a, the ram 112a, the saddle 114a, and the cross rail 116a are referred to as supports 102a, 108a, 110a, 112a, 114a. 116a. Each of the transfer units 102b, 108b, 110b, 112b, 114b, and 116b is included in the concept of the “transfer unit” of the present invention. Servo motors 102c, 108c, 110c, 112c, 114c, and 116c of the transfer units 102b, 108b, 110b, 112b, 114b, and 116b are connected to the corresponding machine axis directions (X-axis direction and A-axis direction) from the numerical controller 200. , C-axis direction, Z-axis direction, Y-axis direction, and W-axis direction) are input, and the transfer amount for each cycle time in each machine axis direction indicated by the input transfer pulse. Accordingly, each of the supports 102a, 108a, 110a, 112a, 114a, and 116a is operated to move in the corresponding machine axis direction. Then, each of the supports 102a, 108a, 110a, 112a, 114a, 116a is transferred in the corresponding machine axis direction, whereby the tool 104 is moved relative to the workpiece 500 to cut the workpiece 500. It is like that.

  In the machine tool as described above, a machining data supply device 150 that supplies CL data (cutter location data) described later, a numerical control device 200 that numerically controls machining of the workpiece 500 by the machine tool, and a machining data supply device 150. And a machining command conversion device 2 that reads the NC program from the CL data supplied from the machine, applies a specific conversion process to the NC program, and outputs the converted NC program to the numerical controller 200. Yes. The machining command conversion apparatus 2 incorporates a machining command conversion program according to the present embodiment. Hereinafter, the configuration of the machining data supply device 150, the numerical control device 200, and the machining command conversion device 2 will be described.

  The machining data supply device 150 supplies CL data that defines how the tool 104 is moved relative to the workpiece 500 when machining the workpiece 500. The processing data supply apparatus 150 is composed of an external terminal such as a personal computer, and incorporates a so-called CAD / CAM (Computer Aided Design / Computer Aided Manufacturing) system. The machining data supply device 150 supplies CL data created by a CAD / CAM system.

  The numerical control device 200 performs various arithmetic processes based on the NC program that indicates the movement locus of the workpiece 500 or the tool 104 when the workpiece 500 is machined, and each support body 102a, 108a, 110a, 112a in each machine axis direction. , 114a, 116a, a transfer pulse indicating a transfer amount between each time of a predetermined cycle time interval is derived, and the transfer pulse is transferred to the servo motors 102c, 108c of the transfer units 102b, 108b, 110b, 112b, 114b, 116b, By outputting to 110c, 112c, 114c, 116c, the transfer of each support 102a, 108a, 110a, 112a, 114a, 116a by each transfer part 102b, 108b, 110b, 112b, 114b, 116b is controlled.

  Specifically, the numerical control device 200 is based on the converted NC program that the machining command conversion device 2 derives and inputs to the numerical control device 200 as described later, and the tool 104 indicates the movement locus indicated by the NC program. In accordance with each machine axis direction (X-axis direction, A-axis direction, C-axis direction, Z-axis), the support bodies 102a, 108a, 110a, 112a, 114a, and 116a are moved in accordance with A mechanical axis path indicating a position to be transferred at each time of a predetermined cycle time interval in the direction, the Y-axis direction, and the W-axis direction) is obtained. The NC program is included in the concept of “machining command” of the present invention, and the converted NC program is included in the concept of “converted processing command” of the present invention. Further, the numerical controller 200 performs pulse interpolation for obtaining a transfer pulse for each cycle time from the derived machine axis path, and each transfer pulse obtained by the pulse interpolation is within a distribution interval having a specific time constant interval width. Post-interpolation acceleration / deceleration processing (acceleration / deceleration processing after pulse interpolation) is performed. Further, the numerical control device 200 outputs the transfer pulse after acceleration / deceleration processing after interpolation to the servo motors 102c, 108c, 110c, 112c, 114c, 116c of the transfer units 102b, 108b, 110b, 112b, 114b, 116b. To control the transfer of the supports 102a, 108a, 110a, 112a, 114a, 116a by the transfer units 102b, 108b, 110b, 112b, 114b, 116b.

  The machining command conversion device 2 according to the present embodiment is applied to the machining data supply device 150 and the numerical control device 200 as described above, and an error caused by the post-interpolation acceleration / deceleration processing of the NC program used by the numerical control device 200 is reduced. The conversion process is performed in advance to convert the direction, and can be optionally applied to an existing numerically controlled machine tool.

  Specifically, the machining command conversion device 2 is connected to the machining data supply device 150 so that data can be exchanged with the machining data supply device 150, and data is exchanged with the numerical control device 200. It is comprised by the arithmetic processing unit as an external terminal connected with respect to the numerical control apparatus 200 so that transfer is possible. The machining command conversion device 2 incorporates a so-called post-processor system and the machining command conversion program of the present embodiment. The machining command conversion device 2 derives the NC program from the CL data and the derived NC. Program conversion processing (described later) is performed. As the processing command conversion device 2, for example, a so-called customer's board used for changing a part of processing contents of arithmetic processing performed by the numerical control device 200 or adding a new processing is used. Is done. An arithmetic processing device that is installed exclusively for NC program derivation and conversion processing and is connected to the numerical control device 200 may be used as the machining command conversion device 2. The machining command conversion device 2 includes a conversion unit 4 and a memory 5.

  The conversion unit 4 is a calculation unit that performs various calculation processes, reads the CL data supplied from the machining data supply device 150, and reads the NC program from the CL data. Specifically, the conversion unit 4 obtains an NC program in which CL data is converted into a data format that can be used by the numerical controller 200. Then, based on the derived NC program, the conversion unit 4 moves the supports 102a, 108a, 110a, 112a, 114a, 116a at each time in order to move the tool 104 according to the movement locus indicated by the NC program. A reference machine axis path indicating a position in each machine axis direction is derived by the same derivation method as the machine axis path derivation method performed by the numerical control device 200. Further, the conversion unit 4 derives a converted machine axis path for each machine axis direction by performing a specific conversion process on the derived reference machine axis path for each machine axis direction, and each derived machine axis direction A process for converting the converted machine axis path into a converted NC program representing the same format as the NC program is performed.

  As the specific conversion process for deriving the post-conversion machine axis path executed by the conversion unit 4, an error from the post-conversion reference path among the end points of blocks to be described later of the reference machine axis path for each machine axis direction Is equal to or less than the corrected boundary value, the machine axis path obtained from the transfer pulse after acceleration / deceleration processing after interpolation in each machine axis direction by the numerical controller 200 and the reference machine axis path in the corresponding machine axis direction A correction amount corresponding to the approximate value of the error is calculated for each machine axis direction, and with the calculated correction amount for each machine axis direction, a machine axis path obtained from the transfer pulse after the post-interpolation acceleration / deceleration processing; An arithmetic process is performed to correct the reference machine axis path in each machine axis direction in a direction (cancellation direction) that cancels an error from the reference machine axis path. In addition, as the specific conversion process, regarding the point where the error with the converted reference path among the end points of the later-described blocks of the reference machine axis path for each machine axis direction exceeds the correction boundary value, A correction amount is calculated by proportional distribution from the correction amounts for the two preceding and following command points, and calculation processing is performed to correct the reference mechanical axis path with the calculated correction amount in the same manner as described above.

  If the trajectory of the tool 104 obtained from the reference machine axis path is, for example, a circle on the XY plane as shown in FIG. 3, the numerical controller 200 performs pulse interpolation on the reference machine axis path. Machine axis path obtained from the post-interpolation acceleration / deceleration process transfer pulse when the obtained transfer pulse is interpolated and accelerated / decelerated after interpolation to obtain the post-interpolation acceleration / deceleration process transfer pulse. The trajectory of the tool 104 instructed based on is shifted radially inward of the trajectory obtained from the reference machine axis path as shown in FIG. The conversion unit 4 approximates an error between the mechanical axis path and the reference mechanical axis path obtained from the transfer pulse after the post-interpolation acceleration / deceleration processing in each machine axis direction (X axis, Y axis) that causes this deviation. Is calculated for each machine axis direction (X-axis, Y-axis), and each machine axis direction (X-axis, Y-axis) in a direction that cancels the error with the calculated correction amount for each machine-axis direction. Each of the reference machine axis paths for (axis) is corrected. As a result, the conversion unit 4 calculates a post-conversion mechanical axis path that provides a trajectory of the tool 104 as shown in FIG. That is, in the form shown in FIG. 4, the trajectory of the tool 104 obtained from the post-conversion mechanical axis path results in a trajectory obtained by correcting the trajectory of the tool 104 obtained from the reference mechanical axis path radially outward.

  In addition, when the plurality of time constants set for the respective machine axis directions include time constants different from the time constants for the other machine axis directions, the conversion unit 4 When converting the converted machine axis path with respect to the direction into the converted NC program, the converted machine axis path is once converted into a temporary conversion NC program represented in the NC program format, and each of the temporary conversion NC programs constituting the temporary conversion NC program is configured. The converted NC program is derived by adjusting the coordinates of the command point in each machine axis direction. Specifically, when adjusting the coordinates of each command point constituting the temporary conversion NC program, the conversion unit 4 sets each machine axis in the distribution interval according to the time constant for each machine axis direction in the post-interpolation acceleration / deceleration processing. Each machine at each command point of the temporary conversion NC program so that the difference in time delay between the transfer pulses after the interpolating acceleration / deceleration processing in each machine axis direction caused by distributing the transfer pulses in the direction is canceled Adjust the coordinates for the axial direction.

  The machining command conversion program according to the present embodiment is incorporated in the conversion unit 4, and various processes (arithmetic processing) executed by the conversion unit 4 are executed according to the commands of the machining command conversion program. Details of the arithmetic processing performed by the conversion unit 4 will be described later.

  Further, the conversion unit 4 outputs the converted NC program to the numerical control device 200 so that the numerical control device 200 obtains a mechanical axis path for each machine axis direction based on the converted NC program. The mechanical axis path obtained from the transfer pulse after performing the interpolation after obtaining the machine axis path from the converted NC program inputted by the numerical controller 200 and performing the post-interpolation acceleration / deceleration processing approximates the reference machine axis path. Therefore, the error with respect to the reference machine axis path is as small as acceptable.

  The memory 5 stores various data such as a correction amount and set values used by the conversion unit 4 to correct the mechanical axis path.

  Next, processing performed by the machining command conversion device 2 will be described in detail with reference to the flowcharts of FIGS. 5 and 6.

  In this process, first, the conversion unit 4 of the machining command conversion device 2 reads CL data supplied from the machining data supply device 150, and derives an NC program from the CL data (step S2).

  Next, the conversion unit 4 derives a reference machine axis path for each machine axis direction from the derived NC program (step S4). Specifically, the NC program read by the conversion unit 4 represents the movement trajectory of the tool 104 at the time of machining the workpiece 500 by the coordinates of command points at each time of a predetermined cycle time interval. The NC program is converted by using an inverse kinematic relational expression, so that the reference representing the position at which each of the supports 102a, 108a, 110a, 112a, 114a, 116a should be transferred in the corresponding machine axis direction at each time. Deriving the machine axis path.

  Next, the conversion unit 4 derives a converted machine axis path for each machine axis direction by performing conversion processing on the derived reference machine axis path for each machine axis direction (step S6). The conversion unit 4 performs a process corresponding to the post-interpolation acceleration / deceleration process (hereinafter referred to as a conversion unit acceleration / deceleration process) on the reference machine axis path in each machine axis direction as the conversion process. A reference error, which is an error between the machine axis path for the axial direction and the reference machine axis path for the corresponding machine axis direction, is calculated for each machine axis direction, and the calculated reference error for each machine axis direction is calculated for each A correction amount corresponding to an approximate value of an error between the machine axis path obtained from the transfer pulse after interpolating acceleration / deceleration processing in the machine axis direction and the reference machine axis path in the corresponding machine axis direction, and each machine axis direction An arithmetic process for deriving a converted machine axis path in each machine axis direction is performed by correcting the reference machine axis path in each machine axis direction in a direction in which the error is canceled (cancelled) by each correction amount. At this time, the conversion unit 4 performs arithmetic processing according to the flowchart shown in FIG. Hereinafter, this calculation process will be described in detail.

  First, the conversion unit 4 performs a conversion unit acceleration / deceleration process including the following calculation process on the reference machine axis path in each machine axis direction (step S22). In order to simplify the explanation, the following description will focus on the acceleration / deceleration processing of the conversion part of the reference machine axis path in one machine axis direction, but the reference machine axis paths in all other machine axis directions are also described. The same conversion unit acceleration / deceleration processing is performed for each machine axis direction.

  The converter 4 converts the reference machine axis path P (t) into a plurality of blocks Pi (t) (i = 1, 2) at predetermined time intervals (cycle times) t [i−1] ≦ t ≦ t [i]. , 3, 4,... Then, the conversion unit 4 calculates a speed function Qi ′ (t) for each of the divided blocks Pi (t). Specifically, the conversion unit 4 sets a certain time in a predetermined block Pi (t) of the reference machine axis path P (t) to t, and sets a specific machine axis direction to be subjected to conversion unit acceleration / deceleration processing. A time constant (the same time constant as the time constant used by the numerical control device 200) is Ti, a value half of the time constant Ti is a, and the numerical control device 200 distributes the transfer pulse in the acceleration / deceleration processing after interpolation. And the distribution function satisfying the following equation (5) is f (T), the mechanical axis path corresponding to the block Pi (t) after the conversion unit acceleration / deceleration processing is Qi (t), and from t−a to t + a When the speed function of the reference mechanical axis path P (t) at each time T in the distribution target section is P ′ (T), the time t of the predetermined block Pi (t) after the conversion unit acceleration / deceleration processing Velocity function Q which is the first derivative function by Calculated based on '(t) following equation (6).

  In the present embodiment, when the numerical control device 200 distributes the transfer pulse, the distribution is performed in a linear distribution format (a format in which the transfer pulse is evenly distributed over the entire distribution section). The distribution function f (T) corresponding to is a linear distribution function expressed by the following equation (7).

f (T) = 1 / 2a (7)
However, in the said Formula (7), the range of the time T is -a <= T <= a.

  The speed function Qi ′ (t) obtained by the above equation (6) is obtained when the section width t [i + 1] −t [i] of the block Pi (t) corresponding to the speed function is larger than the time constant Ti = 2a. It is expressed differently in the small case and the small case. The speed function Qi ′ (t) in each case is as follows.

  When the section width t [i + 1] −t [i] of the block Pi (t) is larger than the time constant Ti = 2a, t [i] −a <t [i] <t [i] + a <t [ The relationship of i + 1] −a <t [i + 1] <t [i + 1] + a holds (see FIG. 7). In this case, the speed function Pi ′ (T) of the reference mechanical axis path P (t) in the block Pi (t) is represented by a bold line in FIG. In this case, the speed function Qi ′ (t) includes a speed function qi11 ′ (t) in a section from t [i] −a to t [i] + a and t [i] + a to t [i + 1]. The speed function qi12 ′ (t) in the section up to −a and the speed function qi13 ′ (t) in the section from t [i + 1] −a to t [i + 1] + a are subdivided.

  A speed function qi11 '(t) in a section from t [i] -a to t [i] + a is expressed by the following equation (8).

  A speed function qi12 '(t) in a section from t [i] + a to t [i + 1] -a is expressed by the following equation (9).

  A function qi13 '(t) in a section from t [i + 1] -a to t [i + 1] + a is expressed by the following equation (10).

  Next, when the section width t [i + 1] -t [i] of the block Pi (t) is smaller than the time constant Ti = 2a, the section width t [i + 1] -t [i] is the time constant Ti = It is classified into a case where the interval width t [i + 1] −t [i] is smaller than a value a half of the time constant Ti, and a case where the interval width t [i + 1] −t [i] is smaller than a value a half of the time constant Ti. FIG. 8 shows a case where the section width t [i + 1] −t [i] of the block Pi (t) is smaller than the time constant Ti = 2a and larger than a value a half of the time constant Ti. Has a relationship of t [i] −a <t [i] <t [i + 1] −a <t [i] + a <t [i + 1] <t [i + 1] + a. FIG. 9 shows a case where the section width t [i + 1] −t [i] of the block Pi (t) is smaller than the half value a of the time constant Ti = 2a. In this case, t [ i] −a <t [i + 1] −a <t [i] <t [i + 1] <t [i] + a <t [i + 1] + a. The speed function Pi ′ (T) of the reference mechanical axis path P (t) in the block Pi (t) in these cases is represented by a thick line in FIGS. 8 and 9. In these cases, the speed function Qi ′ (t) is equal to the speed function qi21 ′ (t) in the section from t [i] −a to t [i + 1] −a and t [i + 1] −a. To a speed function qi22 ′ (t) in a section from t [i] + a to a speed function qi23 ′ (t) in a section from t [i] + a to t [i + 1] + a.

  A function qi21 '(t) in a section from t [i] -a to t [i + 1] -a is expressed by the following equation (11).

  A function qi22 '(t) in a section from t [i + 1] -a to t [i] + a is expressed by the following equation (12).

  A function qi23 '(t) in a section from t [i] + a to t [i + 1] + a is expressed by the following equation (13).

  Then, the conversion unit 4 integrates the speed functions Qi ′ (t) so that the speed functions Qi ′ (t) for the respective blocks calculated as described above are connected to each other, whereby the overall speed function Q ′ (t ) And the calculated overall speed function Q ′ (t) is integrated to calculate the mechanical axis path Q (t) after the conversion portion acceleration / deceleration processing.

  Thereafter, the conversion unit 4 subtracts the reference mechanical axis path P (t) for the corresponding machine axis direction from the calculated machine axis path Q (t) after the conversion unit acceleration / deceleration processing for each machine axis direction. A reference error that is an error between the mechanical axis path Q (t) after the conversion unit acceleration / deceleration processing and the reference mechanical axis path P (t) in each machine axis direction is calculated (step S24). At this time, the conversion unit 4 calculates a reference error for each end point of each block Pi (t). Specifically, the conversion unit 4 calculates a reference error e [i] for each end point of each block Pi (t) by the following equation (14).

e [i] = Q (t [i])-P (t [i]) (14)
In the conversion unit acceleration / deceleration processing by the conversion unit 4 of the present embodiment, the distribution target section [t−a, t + a] before and after the time t as shown in the above formulas (5) and (6). The distribution value P ′ (T) · f (t at time t when the velocity function P ′ (T) at each time T is distributed according to the distribution function f (T) within the interval from T−a to T + a. -T) is integrated over the interval from t-a to t + a. However, in the post-interpolation acceleration / deceleration processing by the numerical controller 200, the transfer pulse of the block between each time for each cycle time is distributed in a distribution section having a section width equal to the time constant after the time corresponding to the end point of the block. Therefore, instead of the above formulas (5) and (6), the following formulas (15) and (16) are used to calculate the velocity function Qi ′ (t) for each block, and for each calculated block Speed function Qi '(t) is integrated to obtain an overall speed function Q' (t), and the obtained overall speed function Q '(t) is integrated to integrate the mechanical axis after the conversion unit acceleration / deceleration processing. The path Q (t) is calculated by a calculation method that more directly corresponds to post-interpolation acceleration / deceleration processing using the above distribution method.

  The above formulas (15) and (16) indicate that the speed function P ′ (T) at each time T in the distribution target section [t−2a, t] before the time t is distributed within the section from T to T + 2a. By integrating the distribution value P ′ (T) · f (t−T) at time t when distributing according to f (T) over the interval from t−2a to t, the speed function Qi ′ (t ). However, a speed function Qi ′ (t) for each block Pi (t) is calculated by the mathematical formulas (15) and (16), and each block Pi (t) is calculated from the calculated speed function Qi ′ (t). When obtaining the machine axis path Qi (t) after the conversion unit acceleration / deceleration processing, the time t in the machine axis path Qi (t) after the conversion unit acceleration / deceleration processing of the obtained block is the reference machine axis path P ( Deviation from time t in the corresponding block Pi (t) of t). For this reason, the reference error e [i] between the mechanical axis path Q (t) and the reference mechanical axis path P (t) after the conversion unit acceleration / deceleration processing is calculated from the above equation (14) without considering the shift of the time t. ), The phase error is included in the obtained reference error e [i]. This phase error occurs not only at the location instructing acceleration / deceleration of the transfer of the object in the reference machine axis path P (t) but also at the location instructing transfer at a constant speed. Such a phase error is not a factor that causes an error in the machining shape of the workpiece 500 when the time constants in the respective machine axis directions are the same, and is therefore excluded from the required reference error e [i]. May be.

  However, when the mechanical axis path Qi (t) after the conversion unit acceleration / deceleration processing is obtained from the speed function Qi ′ (t) for each block Pi (t) calculated by the above equations (15) and (16), the reference If the phase error element is to be excluded from the error e [i], the mechanical axis path Qi (t) after the conversion unit acceleration / deceleration processing and the block Pi (t) corresponding to the reference mechanical axis path P (t) It is necessary to calculate the reference error e [i] according to the above equation (14) after associating the time t shifted between them, and this time t association is a complicated process. For this reason, in this embodiment, the conversion part acceleration / deceleration process using said Formula (5), (6) is employ | adopted. In the conversion unit acceleration / deceleration processing using the above formulas (5) and (6), the speed function P ′ (T) at each time T is within an equal section [T−a, T + a] around the time T. Therefore, in the region instructing transfer at a constant speed in the reference machine axis path P (t), the machine axis path Qi (t) after the conversion portion acceleration / deceleration processing and the reference machine axis path P (t The time t does not deviate from the corresponding block Pi (t). For this reason, the association of the time t shifted between the mechanical axis path Qi (t) after the conversion unit acceleration / deceleration processing as described above and the corresponding block Pi (t) of the reference mechanical axis path P (t) is performed. Even if the reference error e [i] is obtained by the above equation (14) without performing the above process, the phase error element can be excluded from the obtained reference error e [i].

  The speed function Qi ′ (t) calculated using the above equations (15) and (16) is specifically expressed as follows.

  When the section width t [i + 1] −t [i] of the block Pi (t) of the reference machine axis path P (t) is larger than the time constant Ti = 2a, t [i] <t [i] + a < The relationship t [i] + 2a <t [i + 1] <t [i + 1] + a <t [i + 1] + 2a holds (see FIG. 10). In this case, the speed function Pi ′ (T) of the reference mechanical axis path P (t) in the block Pi (t) is represented by a thick line in FIG. In this case, the speed function Qi ′ (t) includes a speed function qi31 ′ (t) in a section from t [i] to t [i] + 2a, and t [i] + 2a to t [i + 1]. It is subdivided into a speed function qi32 ′ (t) for the section and a speed function qi33 ′ (t) for the section from t [i + 1] to t [i + 1] + 2a.

  A speed function qi31 '(t) in a section from t [i] to t [i] + 2a is expressed by the following equation (17).

  A speed function qi32 '(t) in a section from t [i] + 2a to t [i + 1] is expressed by the following equation (18).

  A speed function qi33 '(t) in a section from t [i + 1] to t [i + 1] + 2a is expressed by the following equation (19).

  Next, when the section width t [i + 1] -t [i] of the block Pi (t) is smaller than the time constant Ti = 2a, the section width t [i + 1] -t [i] is the time constant Ti = It is classified into a case where the interval width t [i + 1] −t [i] is smaller than a value a half of the time constant Ti, and a case where the interval width t [i + 1] −t [i] is smaller than a value a half of the time constant Ti. FIG. 11 shows a case where the section width t [i + 1] -t [i] of the block Pi (t) is smaller than the time constant Ti = 2a and larger than a value a half of the time constant Ti. Has a relationship of t [i] <t [i] + a <t [i + 1] <t [i] + 2a <t [i + 1] + a <t [i + 1] + 2a. FIG. 12 shows a case where the section width t [i + 1] −t [i] of the block Pi (t) is smaller than the half value a of the time constant Ti = 2a. In this case, t [ i] <t [i + 1] <t [i] + a <t [i + 1] + a <t [i] + 2a <t [i + 1] + 2a. The speed function Pi ′ (T) of the reference mechanical axis path P (t) in the block Pi (t) in these cases is represented by a thick line in FIGS. 11 and 12. In these cases, the speed function Qi ′ (t) includes the following speed function qi41 ′ (t) from t [i] to t [i + 1], and t [i + 1] to t [i] + 2a. Are subdivided into a speed function qi42 ′ (t) in the interval up to and a speed function qi43 ′ (t) in the interval from t [i] + 2a to t [i + 1] + 2a.

  A speed function qi41 '(t) in a section from t [i] to t [i + 1] is expressed by the following equation (20).

  A speed function qi42 '(t) in a section from t [i + 1] to t [i] + 2a is expressed by the following equation (21).

  A speed function qi43 '(t) in a section from t [i] + 2a to t [i + 1] + 2a is expressed by the following equation (22).

  Comparing the above equations (8) to (10) with the above equations (17) to (19), the velocity functions qi11 ′ (t), qi12 ′ ( t) and qi13 ′ (t) are obtained by changing the time t of the speed functions qi31 ′ (t), qi32 ′ (t) and qi33 ′ (t) obtained by the above equations (17) to (19) to half the time constant Ti. It can be seen that the speed function is shifted by the value a. Further, comparing the above formulas (11) to (13) with the above formulas (20) to (22), the velocity functions qi21 ′ (t) and qi23 obtained by the above formulas (11) and (13) are obtained. '(T) is a speed function obtained by shifting the time t of the speed functions qi41' (t) and qi43 '(t) obtained by the above formulas (20) and (22) by half the value a of the time constant Ti. I know that there is. The time difference corresponding to half the value a of the time constant Ti is caused by the difference in the distribution format of the speed function Pi ′ (T).

  The reference error e [i] calculated by the conversion unit 4 based on the above formulas (5) to (14) is the post-interpolation acceleration / deceleration process performed by the numerical controller 200 when the post-interpolation acceleration / deceleration process is performed. This value is substantially equal to a value obtained by excluding an element of a phase error that affects the machining shape of the workpiece 500 from an error between a machine axis path and a reference machine axis path obtained from a later transfer pulse. Hereinafter, this point will be described.

  The numerical control device 200 obtains a mechanical axis path (command path) from the input NC program, and derives a transfer pulse by performing pulse interpolation on the obtained mechanical axis path. The machine axis path derived by the numerical controller 200 is set to p (t), the cycle time is set to Δt seconds, the time constant is set to A = n · Δt (seconds), and the first 0th cycle after starting, that is, time 0 Cycle from time to time Δt is cycle (0) and i-th cycle, that is, cycle from time i · Δt to time (i + 1) · Δt is cycle (i), transfer in cycle (i) The transfer pulse Δp (i) indicating the quantity can be expressed by the following equation (23).

Δp (i) = p ((i + 1) · Δt) −p (i · Δt) (23)
The numerical controller 200 performs post-interpolation acceleration / deceleration processing using a linear distribution function on the derived transfer pulse. In post-interpolation acceleration / deceleration processing using a linear distribution function, the transfer pulse Δp (i) of cycle (i) is set to a length equal to the time constant A between cycle (i) and cycle (i + n−1). The transfer pulses of all cycles are distributed according to a distribution method in which (p ((i + 1) · Δt) −p (i · Δt)) / n is evenly distributed to each cycle in the distribution interval, and then each cycle The transfer pulse after the acceleration / deceleration process after interpolation is calculated by integrating the distribution value of the transfer pulse every time. From this, the transfer pulse Δq [j] of the j-th cycle (j) after post-interpolation acceleration / deceleration processing is the transfer pulse Δp [i] of each cycle from cycle (j−n + 1) to cycle (j). (I = j−n + 1, j−n + 2,..., J−2, j−1, j) is obtained by accumulating each distribution value multiplied by 1 / n. Specifically, the numerical control device 200 calculates the transfer pulse Δq [j] after post-interpolation acceleration / deceleration processing by the following equation (24).

  Since the transfer pulse Δq [j] after the post-interpolation acceleration / deceleration processing corresponds to the transfer amount during the cycle time Δt seconds in the cycle (j), by dividing both sides of the equation (24) by Δt, The average speed in cycle (j) is determined. That is, the average speed in the cycle (j) is obtained by the following equation (25).

  Here, since the time constant A = n · Δt, it can be expressed as 1 / n = 1 / (A · Δt), where j · Δt is time t and i · Δt is time T, the above formula ( 25) can be transformed into the following equation (26).

  This mathematical formula (26) shows the distribution value when the average speed (p (T + Δt) −p (T)) / Δt in the cycle (i) is evenly distributed in the distribution section having the section width of A · Δt. This means that integration is performed for each cycle from the cycle of i = j−n + 1 to the cycle of i = j. Since the average speed in cycle (j) is equal to the average speed Δq (t) / Δt at time t, the following equation (27) holds.

  Here, when n is infinite, Δt can be expressed as dt, Δq (t) / Δt can be expressed as q ′ (t), and (p (T + Δt) −p (T)) / Δt. Can be expressed as p ′ (T). As described above, j · Δt = t, and (j−n + 1) · Δt = j · Δt−n · Δt + Δt = t−A + Δt. When n is infinite, Δt is approximated to 0, so that t−A + Δt becomes t−A. From these, the following equation (28) can be derived based on the above equation (27).

  In the conversion unit acceleration / deceleration processing by the conversion unit 4, a distribution function having a constant value of 1 / 2a is used (see the above equation (7)). Therefore, the velocity function after the conversion unit acceleration / deceleration processing by the above equation (16) is used. When calculating Qi ′ (t), the speed function Qi ′ (t) is expressed by the following equation (29).

  In this equation (29), 2a is a time constant and corresponds to A in the above equation (28). The velocity function q ′ (t) to be obtained is equal. From this, the conversion unit obtained by integrating the mechanical axis path obtained from the transfer pulse after the interpolation unit acceleration / deceleration processing by the numerical controller 200 and the speed function Qi ′ (t) obtained by the above equation (16). It can be seen that the machine axis path Qi (t) after the acceleration / deceleration processing is substantially equal, and the error between the two machine axis paths and the reference machine axis path is substantially equal. As described above, the mechanical axis path Qi (t) after the conversion unit acceleration / deceleration processing obtained by integrating the speed function Qi ′ (t) obtained by the above equation (6) and the reference mechanical axis path Pi ( The reference error e [i] with respect to t) is equal to the mechanical axis path Qi (t) after conversion unit acceleration / deceleration processing obtained by integrating the speed function Qi ′ (t) obtained by the above equation (16) and the reference. Since this is equal to a value obtained by eliminating an element of phase error caused by a shift in time t that does not affect the machining shape of the workpiece 500 from an error with respect to the mechanical axis path Pi (t), as a result, the conversion of the present embodiment The reference error e [i] calculated by the unit 4 based on the above formulas (5) to (14) is the mechanical axis path obtained from the transfer pulse after the numerical controller 200 performs the post-interpolation acceleration / deceleration processing and the reference. Because of the error with the machine axis path, It is substantially equal to a value obtained by eliminating the elements of the phase errors do not affect the factory configuration.

  The conversion unit 4 calculates the reference error e [i] for each end point of each block Pi (t) as described above, and then performs the first correction on each end point of each block Pi (t) based on the correction boundary value. The target point and the second correction target point are classified (step S26). The second correction target point includes a corner portion (for example, the vertex of the polygon when the trajectory indicated by the mechanical axis path indicates a polygonal trajectory), and the specification immediately after the first start point of the mechanical axis path. End point located in the section (constant section immediately after the start of transfer), end point located in the specific section just before the last end point of the machine axis path (predetermined section just before the stop of the transfer), specific section where the speed change needs to be relieved suddenly The end point located at is included. The first correction target point is an end point other than the second correction target point, and is an end point located in a section instructing smooth transfer in the mechanical axis path. The correction boundary value is stored as a set value in the memory 5, and the conversion unit 4 first determines that the reference error e [i] is equal to or less than the correction boundary value among the end points of each block Pi (t). A point to be corrected is a point where the reference error e [i] exceeds the correction boundary value.

Then, the conversion unit 4 calculates a correction amount for each of the first correction target point and the second correction target point (step S28). Specifically, for the first correction target point, the conversion unit 4 sets a value equal to the reference error e [i] of the point as the correction amount h1 [i] for the first correction target point. In addition, for the second correction target point, the conversion unit 4 determines the distance L _b between the second correction target point and the first correction target point immediately before the second correction target point, and the second correction target point. It obtains a distance L _a between the correction target point and the nearest first correction target point after the second correction target point, for the second correction target point by proportional distribution from the following equation (30) A correction amount h2 [i] is obtained. In the following equation (30), e _b [i] is a reference error with respect to the first correction target point immediately before the second correction target point, and e _a [i] is the second correction target. This is a reference error for the first correction target point immediately after the target point.

h2 [i] = (e _b [i] × L _a + e _a [i] × L _b ) / (L _b + L _a ) (30)
Then, the conversion unit 4 causes the memory 5 to store the correction amounts h1 [i] and h2 [i] for each end point of each block Pi (t) obtained as described above.

  Thereafter, the conversion unit 4 converts the reference machine axis path P (t) by correcting the correction amounts h1 [i] and h2 [i] for each end point of each block Pi (t) stored in the memory 5. The rear machine axis path is derived. Specifically, the conversion unit 4 subtracts the correction amount h1 [i] set for the point from the value of the first correction target point for the first correction target point among the end points of each block Pi (t). Thus, the first correction target point is corrected, and the correction amount h2 [i] set for the second correction target point from the value of the second correction target point among the end points of each block Pi (t). The second correction target point is corrected by subtracting (step S30).

  Next, the conversion unit 4 converts the converted machine axis path for each machine axis direction derived as described above into a converted NC program that represents the NC program format (step S8 in FIG. 5). In this conversion process, when the time constant set for each machine axis direction is the same, the conversion unit 4 converts the converted machine axis path for each machine axis direction into the NC program format as it is. When the NC program after conversion is derived by doing this, the time constants that are different from the time constants for the other machine axis directions are included in the multiple time constants set for each machine axis direction. In the post-interpolation acceleration / deceleration process due to the difference between these time constants, a time constant difference adjustment process is performed to eliminate the time delay difference between the machine axis directions, and the converted NC program Is derived.

  In this time constant difference adjustment process, the conversion unit 4 once converts the converted machine axis path for each machine axis direction into a temporary conversion NC program that represents the NC program format, and then configures the temporary conversion NC program. The coordinate of each command point in each machine axis direction is adjusted to obtain a converted NC program. The conversion unit 4 derives the converted NC program from the temporary conversion NC program as follows.

  Here, it is assumed that the temporary conversion NC program is configured by a plurality of command points at each time t [k] (k = 0, 1, 2,..., N) at a predetermined cycle time interval. Also, the machine axis direction in which the largest time constant is set among the plurality of machine axis directions is the m-axis direction, the time constant set for the m-axis direction is Tm, and the machine axis direction is different from the m-axis direction. A predetermined machine axis direction in which a time constant smaller than the time constant Tm in the m-axis direction is set is an n-axis direction, and a time constant set in the n-axis direction is To. For each command point at each time t [k] of the temporary conversion NC program, the conversion unit 4 keeps the coordinates in the m-axis direction as it is, and delays the coordinates in the n-axis direction by (Tm−To) / 2. Adjust to coordinates.

  Specifically, the conversion unit 4 directly converts the m-axis direction coordinates of each command point at each time t [k] of the temporary conversion NC program as m of each command point at each time t [k] of the NC program after conversion. While the coordinate in the axial direction is used, the coordinate in the n-axis direction at each time t [k] + (Tm−To) / 2 is obtained from the temporary conversion NC program, and each time of the NC program after conversion is obtained by converting the obtained coordinates. The coordinates in the n-axis direction of each command point at t [k] are used. When the conversion unit 4 obtains coordinates in the n-axis direction at each time t [k] + (Tm−To) / 2 from the temporary conversion NC program, a certain time t [c] + (Tm -To) / 2 is coincident with any one of the times t [k], the coordinate in the n-axis direction of the command point of the temporary conversion NC program at the coincident time is represented by the time t [k]. c] + (Tm−To) / 2 coordinates in the n-axis direction, and when the time t [c] + (Tm−To) / 2 does not match any of the times t [k], each time The time t [c] is proportionally distributed from the coordinates in the n-axis direction of the command point of the temporary conversion NC program at the two most recent times before and after the time t [c] + (Tm−To) / 2 among t [k]. ] The coordinates in the n-axis direction at + (Tm−To) / 2 are obtained.

  The conversion unit 4 sets the NC program after the time constant difference adjustment processing for the temporary conversion NC program as described above as the converted NC program, and outputs the converted NC program to the numerical controller 200 (step S10). The processing performed by the machining command conversion device 2 is performed as described above.

  In the present embodiment, the conversion unit 4 of the machining command conversion device 2 has a machine axis direction corresponding to a machine axis path obtained from a transfer pulse for each machine axis direction after post-interpolation acceleration / deceleration processing by the numerical control device 200. A correction amount corresponding to an approximate value of an error with respect to the reference machine axis path is calculated for each machine axis direction, and a reference machine for each machine axis direction in a direction to cancel the error with the correction amount for each machine axis direction. A converted machine axis path in which the axis path is corrected is calculated, the converted machine axis path for each calculated machine axis direction is converted into a converted NC program, and the numerical control device 200 performs each conversion based on the converted NC program. In order to output the converted NC program to the numerical control device 200 so as to derive the mechanical axis path in the machine axis direction, the numerical control device 200 includes a compensation performed by the numerical control device 200. It is possible to enter the post-acceleration and deceleration each machine axis every pre anticipation is converted NC program is corrected for each machine axis in a direction to cancel the error errors that occur due to processing. For this reason, when the numerical controller 200 performs the post-interpolation acceleration / deceleration processing, the reference machine for the machine axis direction corresponding to the machine axis path for each machine axis direction obtained from the transfer pulse after the post-interpolation acceleration / deceleration processing. An error occurring between the axis path and the axis path can be made minute, and as a result, an error in the machining shape of the workpiece 500 caused by the post-interpolation acceleration / deceleration processing can be reduced to a minute value.

  In this embodiment, the machining command conversion device 2 configured by incorporating a processing command conversion program into an arithmetic processing device configured to be able to exchange data with the numerical control device 200 performs numerical values. Since errors generated by post-interpolation acceleration / deceleration processing performed by the control device 200 can be reduced, the control program currently used in the numerical control device 200 of an existing machine tool can be used as it is. For this reason, compared with the case where the whole control program used with the numerical control apparatus 200 is replaced or the control program is modified, a short period of time is achieved while reducing the burden on the cost and work. Thus, it is possible to implement a measure for reducing an error caused by the post-interpolation acceleration / deceleration process.

  In the present embodiment, since the above time constant difference adjustment process is performed in the derivation of the converted NC program, the post-interpolation acceleration / deceleration process by the numerical controller 200 due to the time constant difference in each machine axis direction. The difference in the time lag between the respective machine axis directions that occurs during the operation can be eliminated, and as a result, the respective machine axis directions caused by the difference in the time lag between the respective machine axis directions. Generation of a phase error between them can be prevented. Specifically, in the above time constant difference adjustment processing, the coordinate in the m-axis direction for which the maximum time constant Tm is set is not delayed from time t [k], but is smaller than the maximum time constant. The coordinates in the n-axis direction where To is set are delayed by (Tm−To) / 2 from the time t [k]. In the post-interpolation acceleration / deceleration processing performed by the numerical control device 200 according to the present embodiment, the mechanical axis path obtained from the transfer pulse after the post-interpolation acceleration / deceleration processing is obtained from the converted NC program input to the numerical control device 200. The machine axis path is delayed by Tm / 2 in the m-axis direction and delayed by To / 2 in the n-axis direction. Therefore, as a result, the mechanical axis path obtained from the transfer pulse after the post-interpolation acceleration / deceleration processing is delayed by Tm / 2 in the m-axis direction and the time in the n-axis direction with respect to the reference mechanical axis path. It is delayed by Tm / 2, which is the sum of the delay (Tm-To) / 2 due to the constant difference adjustment process and the delay To / 2 due to the post-interpolation acceleration / deceleration process. In other words, the same Tm / 2 delay occurs in the m-axis direction and the n-axis direction, so that a phase error can be prevented from occurring between these machine axis directions.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and further includes meanings equivalent to the scope of claims for patent and all modifications within the scope.

  In the above embodiment, the machining command conversion program has already been incorporated into the machining command conversion device 2 as an example. However, the machining command conversion program according to the present invention is stored in various storage media, and the storage medium is It may be introduced into the arithmetic processing device from the storage medium by being coupled to an arithmetic processing device capable of transferring data to and from the numerical control device 200. A configuration according to such a modification is shown in FIG. In this modification, as the storage medium 22 in which the machining command conversion program is stored, a disk-shaped storage medium such as a CD-R, various card-shaped storage media, or incorporated in the arithmetic processing device or the arithmetic processing device And various externally connected memories and hard disks. And in this modification, the arithmetic processing unit 12 which comprises a process command conversion apparatus is provided with the coupling | bond part 8 which can couple | bond the storage medium 22 with which the process command conversion program was memorize | stored. The coupling unit 8 is electrically connected to the conversion unit 4. When the storage medium 22 is coupled to the coupling unit 8, the conversion unit 4 converts the machining command from the storage medium 22 via the coupling unit 8. The program can be read.

  According to this configuration, the processing command conversion program stored in the storage medium 22 can be introduced into the arithmetic processing unit 12 simply by coupling the storage medium 22 to the coupling unit 8 of the arithmetic processing unit 12. The work of introducing the machining command conversion program into the existing arithmetic processing unit 12 can be easily performed.

  Further, the machining command conversion device, the machining command conversion program, and the storage medium storing the program according to the present invention can be applied to a numerical control device for controlling a machine tool having a portal frame as shown in FIG. It is not limited. For example, the machining command conversion device according to the present invention, the machining command conversion program, and the storage medium storing the program are also applied to a numerical control device for controlling a machine tool having a parallel mechanism, a lathe, and other various machine tools. Is possible.

  In the above embodiment, the linear distribution function is used in the conversion unit acceleration / deceleration processing. However, the distribution function used in the conversion unit acceleration / deceleration processing is a distribution function of a type other than the linear distribution function. May be. However, the distribution function needs to correspond to a distribution format when the numerical controller distributes the transfer pulse to the distribution section in the post-interpolation acceleration / deceleration processing.

  For example, when the numerical control device distributes the transfer pulse in the distribution section in the so-called bell-type distribution format in the post-interpolation acceleration / deceleration processing, the conversion unit uses a so-called bell-type distribution function in the conversion unit acceleration / deceleration processing. That's fine. Such a bell-shaped distribution function f (t) is expressed by the following equation, for example.

  Note that f (t) = 0 outside the distribution interval −a ≦ t ≦ a.

  In the conversion unit acceleration / deceleration processing, the above formulas (15) and (16) may be used instead of the above formulas (5) and (6). However, in this case, when calculating the error between the mechanical axis path after the conversion unit acceleration / deceleration process and the reference machine axis path, the machine axis path after the conversion unit acceleration / deceleration process and the reference machine axis path are subtracted from each other. After associating the times of the points (time adjustment), the points are subtracted to calculate an error.

  When the conversion unit 4 calculates the correction amount of the reference machine axis path, the error between the machine axis path after the conversion unit acceleration / deceleration processing and the reference machine axis path is calculated, and the correction amount is corrected by the calculated error. The routine of correcting the reference mechanical axis path with the corrected amount of correction and performing the acceleration / deceleration processing on the converted mechanical axis path again may be repeated a plurality of times (for example, about 2 to 3 times). In this case, the mechanical axis path obtained from the transfer pulse after the post-interpolation acceleration / deceleration processing by the numerical controller 200 can be brought closer to the reference mechanical axis path, and errors caused by the post-interpolation acceleration / deceleration processing can be further reduced. it can.

  In addition, the conversion unit of the machining command conversion device creates a parametric variable mechanical axis path from the NC program and obtains a parametric variable time function representing the correlation between the parametric variable and time for performing various interpolations. A reference machine axis path for time display may be obtained from the parameter time function and the machine axis path of the parameter display, and the converted machine axis path may be obtained from the reference machine axis path.

  In the above embodiment, the processing data supply device is described as supplying CL data, but the present invention is not limited to such a form. For example, the machining data supply device may supply an NC program. In this case, the machining data supply device has a function for creating CL data (CAD / CAM system) and a function for deriving and outputting an NC program from the created CL data (post processor). That's fine. In this case, the machining command conversion device does not have a post-processor function, derives a reference machine axis path based on the NC program supplied from the machining data supply device, and the reference machine axis path May be converted to a converted machine axis path, and a converted NC program may be derived from the reference machine axis path and output.

  Also, machining command conversion for converting the NC program of the present invention into an NC program after conversion into an existing processing device comprising a device incorporating a CAD / CAM system, a device incorporating a post processor, and a numerical control device. The device may additionally be applied.

2 Processing command conversion device 4 Conversion unit 8 Coupling unit 12 Arithmetic processing device 22 Storage medium 102 Work transfer device (transfer device)
102a Table (support)
102b Table support body transfer part (transfer part)
104 Tool 108 Oscillator (Transfer device)
108a Swing support (support)
108b Oscillating support transfer part (transfer part)
110 Rotating device (transfer device)
110a Rotating support (support)
110b Rotating support transfer part (transfer part)
112 First vertical transfer device (transfer device)
112a ram (support)
112b Ram transfer part (transfer part)
114 Horizontal transfer device (transfer device)
114a saddle (support)
114b Saddle transfer section (transfer section)
116 Second vertical transfer device (transfer device)
116a Cross rail (support)
116b Cross rail transfer part (transfer part)
500 workpieces

In order to achieve the above object, a machining command conversion program according to the present invention comprises a plurality of transfer devices for transferring a workpiece or a tool for machining the workpiece to the workpiece to machine the workpiece, Each of the transfer devices includes a support for supporting the object, and an arithmetic process provided in a machine tool having a transfer unit that transfers the object by transferring the support in a specific machine axis direction. A machine axis path indicating a position at which each support body is to be transferred at each time of a predetermined cycle time interval in each corresponding machine axis direction, and each machine axis is determined from the determined machine axis path A transfer pulse indicating the transfer amount of each support in the block between each time in the direction is obtained, and the obtained transfer pulse for each machine axis direction is associated with the machine axis direction. The post-interpolation acceleration / deceleration processing is calculated by performing post-interpolation acceleration / deceleration processing that distributes and accumulates within the distribution interval having a specific time constant interval width set for the post-interpolation acceleration / deceleration. The present invention is applied to an arithmetic processing device configured to be able to exchange data with a numerical control device that controls transfer of the support by the transfer unit of each transfer device in accordance with a transfer pulse after processing. A machining command conversion program for moving the tool based on a machining command that represents a movement trajectory of the tool at the time of machining of the workpiece by coordinates of the command points at each time in the respective machine axis directions. A path deriving step for deriving a reference machine axis path indicating a position in each machine axis direction in which each support is to be transferred at each time in order to move according to a trajectory; and in each derived machine axis direction A path conversion step for deriving a converted machine axis path for each of the machine axis directions by performing a specific conversion process on the reference machine axis path, and the converted machine axis path for each of the machine axis directions A machining command conversion step for converting into a converted machining command represented in the form of the machining command, and the numerical control unit so that the numerical control device obtains the machine axis path for each of the machine axis directions based on the converted machining command. An output step of outputting the post-conversion machining command to the control device, and causing the arithmetic processing unit to execute the post-interpolation acceleration / deceleration processing for each of the machine axis directions as the specific conversion processing in the path conversion step. A correction amount corresponding to an approximate value of an error between the machine axis path obtained from a later transfer pulse and the reference machine axis path corresponding to the machine axis direction is The post-conversion machine axis path that is calculated for each machine axis direction and that has corrected the reference machine axis path for each machine axis direction in a direction that cancels the error with the calculated correction amount for each machine axis direction. In the arithmetic processing that causes the arithmetic processing device to execute arithmetic processing for calculating the calculation processing device, the acceleration / deceleration after interpolation in the reference mechanical axis path for each of the machine axis directions. A process corresponding to the process is performed, and a reference error, which is an error between the machine axis path for each machine axis direction after the process and the reference machine axis path corresponding to the machine axis direction, is determined for each machine axis direction. In the processing corresponding to the post-interpolation acceleration / deceleration processing, the numerical control device performs the preceding calculation in which the calculated reference error for each machine axis direction is the correction amount for each machine axis direction. Using a distribution function representing a distribution form corresponding to a distribution form for distributing each transfer pulse, a speed function that is a first-order differential function of the reference machine axis path is distributed, and the distributed value is integrated, and obtained by the integration. By further integrating the function, the arithmetic processing unit is caused to execute processing for calculating a post-processing mechanical axis path corresponding to the post-interpolation acceleration / deceleration processing .

In the machining command conversion program, the processing corresponding to the prior SL interpolated acceleration process, the time and t, the half value of the time constant set for the mechanical axis direction for performing the process as a, t P ′ (T) represents a speed function that is a first-order differential function of the reference mechanical axis path at each time T in a section extending from −a to t + a, and represents a distribution form in which the numerical controller distributes the transfer pulse; When a distribution function satisfying the following equation (1) is defined as f (T), a speed function Q ′ (t), which is a first-order differential function of the machine axis path after the processing corresponding to the post-interpolation acceleration / deceleration processing, is expressed by the following equation: A process of calculating a machine axis path Q (t) after processing corresponding to the post-interpolation acceleration / deceleration processing by calculating based on (2) and integrating the calculated speed function Q ′ (t). It is preferable to have an arithmetic processing unit execute it. There.

The machining command conversion device according to the present invention includes a plurality of transfer devices for transferring a workpiece or a tool for machining the workpiece to the workpiece to process the workpiece, and each of the transfer devices includes the object. Are provided in machine tools each having a support for supporting the object and a transfer unit for transferring the object by transferring the support in a specific machine axis direction. A machine axis path indicating a position to be transferred at each time of a predetermined cycle time interval in the machine axis direction is obtained, and each support in the block between each time in the machine axis direction is obtained from the obtained machine axis path. A distribution section having a specific time constant section width set for the corresponding machine axis direction is determined for each transfer pulse for each machine axis direction. The post-interpolation acceleration / deceleration processing transfer pulse is obtained by performing post-interpolation acceleration / deceleration processing that is distributed and integrated to the transfer unit. A machining command conversion device applied to a numerical control device for controlling the transfer of the support according to the above, wherein the movement trajectory of the tool at the time of machining the workpiece is the direction of each machine axis of the command point at each time A reference machine axis path indicating a position in each machine axis direction to which each support should be transferred at each time in order to move the tool according to the movement trajectory based on a machining command represented by the coordinates of The converted machine axis path for each machine axis direction is derived by performing a specific conversion process on the reference machine axis path for each derived machine axis direction, and each of the derived machine axes The converted machine axis path for the direction is converted into a converted machining command that is expressed in the form of the machining command, and the numerical control device converts the machine axis path for each machine axis direction based on the converted machining command. A conversion unit that outputs the post-conversion machining command to the numerical control device so as to obtain the transfer pulse after the post-interpolation acceleration / deceleration processing in each machine axis direction as the specific conversion processing; A correction amount corresponding to an approximate value of an error between the machine axis path obtained from the reference machine axis path with respect to the corresponding machine axis direction is calculated for each machine axis direction, and each calculated machine axis direction is calculated. There row arithmetic processing for calculating the converted mechanical axis path of the reference machine axis path corrected for the respective mechanical axis direction in a direction to cancel the error correction amount for each, the conversion unit of the specific In the calculation process performed as the conversion process, a process corresponding to the post-interpolation acceleration / deceleration process is performed on the reference machine axis path in each machine axis direction, and the machine axis path in each machine axis direction after the process is performed. A reference error that is an error from the reference machine axis path in the corresponding machine axis direction is calculated for each machine axis direction, and the calculated reference error for each machine axis direction is calculated for each machine axis. In the processing corresponding to the post-interpolation acceleration / deceleration processing as the correction amount for each direction, the numerical control device uses the distribution function that represents a distribution format corresponding to a distribution format in which each transfer pulse is distributed. The speed function, which is the primary differential function of the path, is distributed, the distributed value is integrated, and the function obtained by the integration is further integrated to further integrate the post-interpolation acceleration / deceleration processing. The calculation process of calculating the mechanical axis path after processing to perform.

In the machining command converting device, the conversion unit is a process corresponding to the prior SL interpolated acceleration process, the time and t, half of the value of the time constant set for the mechanical axis direction for performing the process And a speed function that is a first-order differential function of the reference mechanical axis path at each time T in a section from t−a to t + a is P ′ (T), and the numerical control device distributes the transfer pulses. Speed function Q ′ that is a first-order differential function of the machine axis path after processing corresponding to the post-interpolation acceleration / deceleration processing, where f (T) is a distribution function that represents the distribution format to be satisfied and satisfies the following expression (3) (T) is calculated based on the following equation (4), and the calculated speed function Q ′ (t) is integrated to integrate the post-interpolation acceleration / deceleration processing corresponding to the post-interpolation mechanical axis path Q (t). It is preferable to perform an arithmetic process for calculating.

Claims (7)

A plurality of transfer devices that transfer a workpiece or a tool that processes the workpiece as a target to transfer the target in order to process the workpiece, and each of the transfer devices includes a support for supporting the target; An arithmetic processing unit provided in a machine tool having a transfer unit for transferring the object by transferring the support in a specific machine axis direction, wherein each of the supports corresponds to each machine axis direction. , A mechanical axis path indicating a position to be transferred at each time of a predetermined cycle time interval is obtained, and the transfer amount of each support in a block between each time in the direction of each mechanical axis from the obtained mechanical axis path The transfer pulse for each of the machine axis directions is obtained and distributed in a distribution section having a specific time constant section width set for the corresponding machine axis direction. The post-interpolation acceleration / deceleration processing transfer pulse is obtained by performing post-interpolation acceleration / deceleration processing to be integrated, and the support by the transfer unit of each transfer device according to the obtained post-interpolation acceleration / deceleration processing post-interpolation processing A machining command conversion program applied to an arithmetic processing device configured to be able to exchange data with a numerical control device that controls the transfer of
Each of the supports for moving the tool according to the movement trajectory based on a machining command that represents the movement trajectory of the tool at the time of machining the workpiece by coordinates of the command points at the respective times with respect to the machine axis directions. A path derivation step for deriving a reference machine axis path indicating a position in each machine axis direction at which the body is to be transferred at each time;
A path conversion step for deriving a converted machine axis path for each machine axis direction by performing a specific conversion process on the reference machine axis path for each derived machine axis direction;
A machining command conversion step for converting the converted machine axis path for each machine axis direction into a converted machining command that is expressed in the format of the machining command;
An output step of outputting the post-conversion machining command to the numerical control device so that the numerical control device obtains the machine axis path for each of the machine axis directions based on the post-conversion machining command; To run
In the path conversion step, as the specific conversion process, the reference machine axis path in the machine axis direction corresponding to the machine axis path obtained from the transfer pulse after the post-interpolation acceleration / deceleration process in the respective machine axis directions The correction amount corresponding to the approximate value of the error with respect to each machine axis direction is calculated for each of the machine axis directions, and the calculated correction amount for each of the machine axis directions cancels the error with respect to each of the machine axis directions. A machining command conversion program for causing the arithmetic processing unit to execute arithmetic processing for calculating the post-conversion mechanical axis path obtained by correcting a reference mechanical axis path. In the arithmetic processing to be executed by the arithmetic processing unit as the specific conversion processing, processing corresponding to the post-interpolation acceleration / deceleration processing is performed on the reference mechanical axis path for each of the machine axis directions. A reference error, which is an error between the machine axis path for the machine axis direction and the corresponding reference machine axis path for the machine axis direction, is calculated for each machine axis direction, and the calculated machine axis direction is calculated for each machine axis direction. The reference error is the correction amount for each machine axis direction,
In the processing corresponding to the post-interpolation acceleration / deceleration processing, the time is t, the half value of the time constant set for the machine axis direction in which the processing is performed is a, and the interval from ta to t + a P ′ (T) is a speed function that is a first-order differential function of the reference mechanical axis path at each time T, and the numerical control device represents a distribution form in which the transfer pulses are distributed and satisfies the following expression (1) When the function is set to f (T), a speed function Q ′ (t), which is a first-order differential function of the machine axis path after the processing corresponding to the post-interpolation acceleration / deceleration processing, is calculated based on the following equation (2). And integrating the calculated speed function Q ′ (t) to cause the arithmetic processing unit to execute a process of calculating a machine axis path Q (t) after processing corresponding to the post-interpolation acceleration / deceleration process. Item 5. A machining command conversion program according to Item 1.

The plurality of time constants set for the respective machine axis directions include time constants having values different from the time constants for the other machine axis directions, and the numerical control device performs the post-interpolation acceleration / deceleration processing. When the transfer pulse of each block in each machine axis direction is distributed, the interval extending from the end point of that block to the end by the section width corresponding to the time constant set in the machine axis direction to be distributed When distributing the transfer pulse within the distribution section, in the machining command conversion step, a temporary conversion step for temporarily converting the converted machine axis path into a temporary conversion machining command expressed in the form of the machining command, and the temporary conversion Causing the arithmetic processing unit to execute an adjustment step of adjusting the coordinates of each command point constituting the machining command in each machine axis direction to obtain the converted machining command.
In the adjustment step, the machine axis directions generated by distributing the transfer pulses in the machine axis directions to the distribution sections according to the time constants in the machine axis directions in the post-interpolation acceleration / deceleration processing. Processing for adjusting the coordinates of the command points of the temporary conversion machining command in the respective machine axis directions so that the difference in the time delay between the transfer pulses after the post-interpolation acceleration / deceleration processing is canceled each time The machining command conversion program according to claim 1, wherein the processing processing device is executed.   A storage medium storing the machining command conversion program according to any one of claims 1 to 3, wherein the machining command conversion program stored in the storage medium is introduced into the arithmetic processing unit. A storage medium coupled to the arithmetic processing unit. A plurality of transfer devices that transfer a workpiece or a tool that processes the workpiece as a target to transfer the target in order to process the workpiece, and each of the transfer devices includes a support for supporting the target; A predetermined cycle time interval in each corresponding machine axis direction provided in each machine tool having a transfer unit for transferring the object by transferring the support in a specific machine axis direction. A mechanical axis path indicating a position to be transferred at each time is obtained, and a transfer pulse indicating a transfer amount of each support in a block between each time in the respective machine axis directions is obtained from the obtained machine axis path. The interpolated acceleration / deceleration for distributing and accumulating the determined transfer pulses for each machine axis direction in a distribution section having a section width of a specific time constant set for the corresponding machine axis direction. A numerical value for determining the transfer pulse after the acceleration / deceleration process after interpolation by performing the process, and controlling the transfer of the support by the transfer unit of each transfer device according to the determined transfer pulse after the acceleration / deceleration process after interpolation A machining command conversion device applied to a control device,
Each of the supports for moving the tool according to the movement trajectory based on a machining command that represents the movement trajectory of the tool at the time of machining the workpiece by coordinates of the command points at the respective times with respect to the machine axis directions. By deriving a reference machine axis path indicating a position in each machine axis direction to which the body should be transferred at each time, and performing a specific conversion process on the reference machine axis path for the derived machine axis direction Deriving a converted machine axis path for each machine axis direction, converting the derived machine axis path for each derived machine axis direction into a converted machining command in the form of the machining command, and A conversion unit that outputs the post-conversion machining command to the numerical controller so that the control device obtains the machine axis path for each machine axis direction based on the post-conversion machining command;
The conversion unit, as the specific conversion process, includes the reference machine axis path for the machine axis direction corresponding to the machine axis path obtained from the transfer pulse after the post-interpolation acceleration / deceleration process for each machine axis direction, and The correction amount corresponding to the approximate value of the error is calculated for each of the machine axis directions, and the reference for each of the machine axis directions in a direction that cancels the error with the calculated correction amount for each of the machine axis directions. A machining command conversion device that performs arithmetic processing for calculating the converted machine axis path after correcting the machine axis path. In the calculation process performed as the specific conversion process, the conversion unit performs a process corresponding to the post-interpolation acceleration / deceleration process on the reference machine axis path with respect to each machine axis direction. A reference error, which is an error between the machine axis path for the machine axis direction and the corresponding reference machine axis path for the machine axis direction, is calculated for each machine axis direction, and the calculated machine axis direction is calculated for each machine axis direction. In the process corresponding to the post-interpolation acceleration / deceleration process, the reference error is the correction amount for each machine axis direction, the time is t, and the time constant set for the machine axis direction in which the process is performed is A half value is a, a speed function that is a first-order differential function of the reference mechanical axis path at each time T in a section from t−a to t + a is P ′ (T), and the numerical control device performs each transfer. pulse Is a linear function of the machine axis path after processing corresponding to the post-interpolation acceleration / deceleration processing, where f (T) is a distribution function that expresses a distribution format that satisfies the following equation (3) Q ′ (t) is calculated based on the following expression (4), and the calculated speed function Q ′ (t) is integrated to obtain a machine axis path Q ( The machining command conversion apparatus according to claim 5, wherein a calculation process for calculating t) is performed.

The plurality of time constants set for the respective machine axis directions include time constants having values different from the time constants for the other machine axis directions, and the numerical control device performs the post-interpolation acceleration / deceleration processing. When the transfer pulse of each block in each machine axis direction is distributed, the interval extending from the end point of that block to the end by the section width corresponding to the time constant set in the machine axis direction to be distributed When distributing the transfer pulse in the distribution section, the conversion unit converts the converted machine axis path in the respective machine axis directions into the converted machining command when the converted machine axis path is converted into the converted machining command. Is temporarily converted into a temporary conversion machining command expressed in the form of the machining command, and then the coordinates of the command points constituting the temporary conversion machining command are adjusted with respect to the respective machine axis directions, and after the conversion And engineering instruction,
When adjusting the coordinates of each command point constituting the provisional conversion machining command, the conversion unit is arranged in the distribution interval corresponding to the time constant for each machine axis direction in the post-interpolation acceleration / deceleration processing. The provisional conversion process so that the difference in the time delay between the transfer pulses after the interpolating acceleration / deceleration processing for each of the machine axis directions caused by distributing the transfer pulses in the machine axis direction is offset The machining command conversion device according to claim 5 or 6, wherein the coordinate of each command point of the command in each machine axis direction is adjusted.

Images