JP2011186939A - Numerical control device and production system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide, in a numerical control device configured to perform processing by compressing a plurality of instruction paths having short path lengths into one, the numerical control device which can perform the processing without deteriorating the processing accuracy at high speed by preventing change in the feed rate of a tool due to the compression. <P>SOLUTION: The device includes a determination allowable feed rate calculation part 3, a compression propriety determination part 4, a compression processing part 5, and an interpolation allowable feed rate calculation part 7. The determination allowable feed rate calculation part 3 calculates, based on an instruction path 12 or/and an after-compression instruction path, a determination pre-compression allowable feed rate or/and a determination after-compression allowable feed rate. The compression propriety determination part 4 determines the propriety of compression based on the determination pre-compression allowable feed rate or/and the determination after-compression allowable feed rate. The compression processing part 5 forms an after-compression instruction path 16 by compressing a plurality of instruction paths into one path based on a compression propriety determination result 15 in the compression propriety determination part 4, and the interpolation allowable feed rate calculation part 7 calculates an interpolation allowable feed state based on the after-compression instruction path 16. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a numerical control device for numerically controlling a machine tool (Numerical Control: NC) or a production system equipped with a numerical control device, and more particularly to replacing (compressing) a plurality of continuous command paths with one command path. Thus, the present invention relates to a numerical control device that realizes high-speed machining or a production system including the numerical control device.

  When machining a three-dimensional shape with a machine tool equipped with a numerical control device, machining may be performed according to a machining program that approximates a free-form surface with a plurality of continuous command paths. The machining program may be created manually if it is a simple shape, but is generally created by CAM (Computer Aided Manufacturing) in the case of a three-dimensional shape including a free-form surface.

  When a machining program is created using CAM, the length of one command path (hereinafter referred to as path length) may be shortened in order to represent a free-form surface as accurately as possible. However, the number of command paths that can be processed within a certain period of time is limited by the data processing capability of the numerical control device of the machine tool. Therefore, when the path length is shortened, the distance that the tool can move, that is, the tool feed speed (hereinafter, actual machining) The feed rate) is limited.

  Therefore, in the conventional numerical control device, a plurality of continuous command paths in the same straight section are compressed into one command path (hereinafter referred to as a post-compression command path) to increase the path length. By performing processing such as allowable feed speed calculation and path correction based on the compressed compressed command path, the processing load is reduced and high-speed machining is realized. Here, whether or not a plurality of consecutive command paths are in the same straight line section, that is, whether or not compression is possible has been determined simply based on the shape information of the local command path. For example, in Patent Document 1 below, it is determined that compression is not possible when the amount of change in the slope of the line segment is greater than or equal to a predetermined value.

Japanese Patent No. 3459155

  However, in the above method, it is possible to make the path error due to compression within a predetermined value, but since the change of the allowable feed speed (details will be described later) due to compression is not taken into consideration, the command feed to the tool by compression is not considered. There is a possibility that the tool command feed speed, which is the speed, may change (here, the tool command feed speed is a feed speed determined irrespective of the data processing capability of the numerical controller, and is a command commanded by the machining program. The smaller of the feed rate and the allowable feed rate determined by the command path, and the actual machining feed rate is the feed rate at which the tool actually moves, and the tool command feed rate and the data processing of the numerical controller The smaller of the maximum feed speed limited by the capacity). For example, in the case of a command path having a gentle corner shape as shown in FIG. 12A, the command paths N2 and N3 are compressed if the change in inclination of the command paths N2 and N3 is small, as shown in FIG. The post-compression command path N′2 is obtained. Here, the arrow in the figure indicates the allowable feed speed, and the length of the arrow indicates the size of the allowable feed speed. Generally, in order to decelerate at a point where acceleration is large, such as a corner, the tool command feed speed is the smaller of the allowable feed speed based on the command path and the command feed speed commanded by the machining program. Therefore, when the allowable feed speed at the command position P2 is smaller than the command feed speed, the command position P2 in the command path before compression shown in FIG. 12A is decelerated at the allowable feed speed at the command position P2. In the post-compression command path shown in FIG. 12B, the allowable feed speed is calculated at the corners of the post-compression command path N′1 and post-compression command path N′2, and the post-compression command path N′2 and post-compression command path N′3. Therefore, the corner becomes gentle with respect to the command path before compression and the allowable feed speed becomes high, so that the tool command feed speed changes due to compression. Further, in the command path before compression shown in FIG. 12 (a), the vehicle is decelerated at the allowable feed speed at the command position P2, whereas in the command path after compression shown in FIG. 12 (b), at command positions P1 and P3. Since the vehicle is decelerating at the allowable feed speed, the deceleration position is shifted. Such a problem appears remarkably in a machining program having a high command feed rate, and is not decelerated at a corner or the like, resulting in a problem that machining accuracy deteriorates. For example, in the case of a curve command path as shown in FIG. 13A, the command paths N1, N2, N3, N4, and N5 are smooth curves, but N1, N2, N3, and N4 and N5 are compressed. As shown in FIG. 13 (b), when compressed into post-compression command paths N′1 and N′2, the change in the slope of the line segment of N′1 and N′2 becomes large, and is allowed at the command position P3. There is a possibility that the feed speed becomes smaller than necessary and the tool command feed speed becomes smaller. The problems mentioned in the above two examples can be dealt with by reducing the change in the slope of the compressible line segment even with the conventional method, but if the change in the slope of the compressible line segment is reduced, the command path is compressed. There is a problem that the effect is lost and high-speed machining cannot be performed.

  Furthermore, in general, the allowable feed speed of a free-form surface approximated by a plurality of consecutive command paths is determined by referring to a global shape in order to calculate an accurate allowable feed speed according to the shape of the command path. May be calculated based on the command path. In that case, the change in the tool command feed speed due to the compression cannot be prevented by the compression propriety determination based only on the local command path shape information as in the conventional compression propriety determination.

  The actual tool trajectory, which is the actual trajectory of the tool, contains a trajectory error corresponding to the actual machining feedrate, so the path where the tool command feedrate has changed due to compression and the path that has not changed are mixed and adjacent. If the actual machining feed rate differs in the path, the actual machining trajectory differs from path to path, leaving a mark on the workpiece, which adversely affects machining accuracy. For this reason, it is more important not to change the actual machining feed rate than the generation of a path error due to compression in die machining having many free-form surfaces.

  The present invention was made to solve such problems, in a numerical control device that performs processing by compressing a plurality of continuous command paths into one path, or a production system including a numerical control apparatus, Equipped with a numerical control device or numerical control device that prevents changes in the tool command feed speed due to compression, and in turn prevents changes in the actual machining feed speed, and enables high-speed machining without deteriorating machining accuracy. The goal is to obtain a production system.

  In order to solve the above-described problems and achieve the object, a numerical control device according to the present invention creates a post-compression command path by compressing a plurality of continuous command paths into one path, and based on the post-compression command path In the numerical control device that controls the machine tool, the numerical control device includes a determination allowable feed rate calculation unit, a compression possibility determination unit, a compression processing unit, and an interpolation allowable feed rate calculation unit, and the determination allowable feed rate. The calculation unit calculates a pre-compression allowable feed speed for determination or / and a post-compression allowable feed speed from the command path or / and the post-compression command path, and the compressibility determination unit determines whether the pre-compression allowable feed speed for determination or / The compression processing unit determines whether or not compression is possible based on the post-compression allowable feed speed for determination, and the compression processing unit converts a plurality of consecutive command paths into one path when the compression availability determination result of the compression availability determination unit is compressible. Compressed pressure Create a post command path, interpolation permissible feed speed calculating unit, and calculates the interpolation permissible feed speed from the post-compression command path.

  The production system according to the present invention is a production system for creating a post-compression command path obtained by compressing a plurality of continuous command paths into one path, and controlling the machine tool based on the post-compression command path. A determination allowable feed speed calculation unit, a compression determination unit, a compression processing unit, and a compression controller including a post-compression data storage unit, and a numerical control device including an interpolation allowable feed rate calculation unit. The calculation unit calculates a permissible pre-compression allowable feed speed or / and a post-compression allowable feed speed from the command path or / and the post-compression command path, and the compressibility determination unit determines whether the pre-compression permissible feed speed for determination or / and The compression processing unit determines whether or not compression is possible based on the post-compression allowable feed speed for determination, and the compression processing unit determines a plurality of continuous command paths when the compression availability determination result in the compression availability determination unit is compressible. The post-compression command path compressed into one path is created, the post-compression data storage unit stores the post-compression command path in the post-compression data buffer, and the interpolation allowable feed speed calculation unit is stored in the post-compression data buffer. An allowable feed speed for interpolation is calculated from the post-compression command path.

  According to this invention, the pre-compression allowable feed speed for determination or / and the post-compression allowable feed speed are obtained before the compression processing unit, and the pre-determination allowable feed speed for determination or / and the post-compression allowable feed after determination are determined. Since it is determined whether or not the compression can be performed based on the speed so that the tool command feed speed does not change, it is possible to prevent a change in the actual machining feed speed due to the compression and realize high-precision machining.

FIG. 1 is a block diagram showing a schematic configuration of a first embodiment of a numerical control apparatus according to the present invention. FIG. 2 is a flowchart showing a flow of processing for creating a post-compression command path in the first embodiment of the present invention. FIG. 3 is an explanatory diagram of a post-compression command path in the first embodiment of the present invention. FIG. 4 is a flowchart showing a flow of processing for calculating an allowable feed speed in the first embodiment of the present invention. FIG. 5 is an explanatory diagram of a tool estimated position in the first embodiment of the present invention. FIG. 6 is an explanatory diagram of a method of calculating acceleration and normal acceleration according to Embodiment 1 of the present invention. FIG. 7 is a flowchart showing a flow of processing for determining whether or not compression is possible in Embodiment 1 of the present invention. FIG. 8 is an explanatory diagram of a tool movement path in the first embodiment of the present invention. FIG. 9 is a flowchart showing a flow of interpolation processing in the first embodiment of the present invention. FIG. 10 is an explanatory diagram of a tool position calculation method according to the first embodiment of the present invention. FIG. 11 is a block diagram showing a schematic configuration of the second embodiment of the present invention. FIG. 12 is an explanatory diagram of corner path compression in the preceding example. FIG. 13 is an explanatory diagram of curve path compression in the preceding example.

  Hereinafter, a first embodiment of a numerical controller according to the present invention will be described in detail with reference to the drawings. The present invention is not limited to the first embodiment.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing a schematic configuration of a first embodiment of a numerical control apparatus according to the present invention. In FIG. 1, a numerical control device 100 includes a machining program reading unit 2, a determination allowable feed rate calculation unit 3, a compression availability determination unit 4, a compression processing unit 5, a movement data creation unit 6, and an interpolation allowable feed rate calculation unit. 7 and an interpolation processing unit 8 are provided.

  First, the machining program reading unit 2 reads a program command 11 commanded by the machining program 1 and outputs a command path 12 and a pre-compression path correction / operation data 13. The path correction / operation data 13 includes information for correcting the command path 12 commanded by the machining program into a tool movement path, the command path 12 command feed speed and operation mode, etc. Contains the information needed to determine.

  In the determination allowable feed rate calculation unit 3, based on the command path 12 output by the machining program reading unit 2, the determination allowable feed rate 14 is determined as the determination allowable feed rate before compression and / or the determination allowable post-compression allowable feed rate. Is calculated. When calculating the post-compression allowable feed speed for determination, a post-compression command path that temporarily compresses the command path 12 is created, and the post-compression allowable feed speed for determination is calculated based on the post-compression command path. .

  The compression propriety determination unit 4 determines whether or not compression is possible based on the pre-determination allowable feed rate for determination and / or the post-determination allowable permissible feed rate output from the determination allowable feed rate calculation unit 3, and determines whether or not compression is possible. The result 15 is output.

  In the compression processing unit 5, based on the compression determination result 15 output from the compression determination unit 4, a new 1 that connects the start points and end points of a plurality of continuous command paths 12 output from the machining program reading unit 2. Two post-compression command paths 16 are output. The compression processing unit 5 also outputs route correction / operation data 17 for the post-compression command route 16. Note that the compression possibility determination unit 4 determines that the command path 12 with different pre-compression path correction / operation data 13 is not compressible as will be described later. Therefore, the compression processing section 5 has a command with different pre-compression path correction / operation data 13. Since the paths 12 are not compressed, the pre-compression path correction / operation data 13 for any command path 12 included in the post-compression command path 16 may be used as the post-compression path correction / operation data 17.

  The movement data creation unit 6 corrects the post-compression command path 16 output from the compression processing unit 5 to a tool movement path based on the post-compression path correction / operation data 17, and a tool necessary for interpolating the tool movement path. The movement data 18 is output. The tool movement data 18 is a tool movement path and movement data necessary for interpolation. Specifically, the start point and end point of each axis for determining the tool position, the path length from the start point to the end point, the tool movement path Information necessary for determining the operation of the machine tool, such as a unit direction vector and a command feed speed, is included.

  The interpolation allowable feed speed calculation unit 7 outputs an interpolation allowable feed speed 19 based on the tool movement data 18 output from the movement data creation unit 6.

  Then, the interpolation processing unit 8 interpolates the tool movement path based on the tool movement data 18 output from the movement data creation unit 6 and the allowable feed speed 19 for interpolation output from the interpolation allowable feed speed calculation unit 7. By outputting the tool position 20 to an acceleration / deceleration processing unit and a servo control device (not shown), the movable unit of each axis (not shown) can be driven. Next, the operation of the numerical control apparatus according to the first embodiment will be described.

<Operation of Machining Program Reading Unit, Determination Allowable Feed Speed Calculation Unit, Compressibility Determination Unit, Compression Processing Unit>
First, a procedure for creating the post-compression command path 16 and post-compression path correction / operation data 17 output from the compression processing unit 5 will be described. FIG. 2 is a flowchart showing an example of the flow of processing for creating the post-compression command path 16 and post-compression path correction / operation data 17 output from the compression processing unit 5 in the first embodiment. Note that the command path number i (i-th command from the machining program) is N (i), and the compressed command path number j (j-th) command path is a compressed command path number j (j-th). The route is N ′ (j). FIG. 3 is a diagram illustrating an example of the relationship between N (i) and N ′ (j) in the first embodiment.

  First, in step S1, the machining program reading unit 2 determines whether or not the machining program 1 is executed for the first time. If it is the first time, the process proceeds to step S2, and the command path number i of the command path N (i) is set. With 0, the post-compression command path number j of the post-compression command path N ′ (j) is initialized with 1, and the process proceeds to step S3. On the other hand, if the machining program 1 is not executed for the first time, the process proceeds to step S3.

  In step S3, the command path number i is incremented by the machining program reading unit 2, and in step S4, the command path N (i) is read from the program command 11 commanded by the machining program 1 by the machining program reading unit 2.

  In step S5, the machining program reading unit 2 determines whether or not the compression process of the post-compression command path N ′ (j) is the first time, that is, the command path N (i) included in the post-compression command path N ′ (j). It is determined whether or not the number is 1, and if the compression process is the first time, the process proceeds to step S6. On the other hand, if the compression is not the first time, the process proceeds to step S7. The processing in step S7 will be described later, and the processing in the case of proceeding to step S6 will be described.

  In step S6, the compression processor 5 initializes the start point of the post-compression command path N ′ (j) with the start point of the command path N (i). In step S9, the compression processing unit 5 sets the end point of the command path N (i) as the end point of the post-compression command path N ′ (j), and the process returns to the processing program reading unit 2 in step S3.

  The post-compression command path N ′ (j) is created by the processing so far. If the process proceeds to step S6 as determined in step S5, the post-compression command path N '(j) and the command path N (i) are the same command path.

  Further description of the flow of processing after returning to step S3 will be continued. In step S3 returned from step S9, the command path number i is incremented, and the command path N (i) is read from the program command 11 commanded by the machining program 1 in step S4. That is, the command path next to the command path read at the previous step S4 is read. In the determination in step S5, since the previous command path N (i-1) has already been compressed, the process proceeds to step S7.

  In step S7, the provisional post-compression command path N ″ (j) in which the end point of the post-compression command path N ′ (j) is tentatively updated by the command path N (i) in the allowable feed speed calculation unit 3 for determination. Is calculated, and the pre-determination permissible pre-compression allowable feed speed or / and the post-compression permissible post-compression allowable feed speed are calculated based on the command path N (k) or / and the provisional post-compression command path N ″ (h). Here, i−δ ≦ k ≦ i + δ (δ: number of prefetch command paths) and h ≦ j.

  In step S8, the compressibility determination unit 4 determines whether or not the post-compression command path N ′ (j) and the command path N (i) can be compressed. If compression is possible, the process proceeds to step S9. The end point of the subsequent command path N ′ (j) is updated with the end point of the command path N (i). Thereafter, by repeating the processes after step S9, a post-compression command path in which a plurality of command paths are compressed is created.

  On the other hand, if compression is impossible, the compression process is terminated, and the command path number i is decremented and the post-compression command path number j is incremented in step S10. In the first embodiment, the command path number i is decremented in step S10 so that the command path N (i) determined to be incompressible is not used thereafter, but the read command path N (i ) May be saved, and the saved command route N (i) may be used instead of reading from the machining program 1 in the next process of step S4.

<< Description of Allowable Feed Speed Calculation Method >>
Here, the calculation method of the pre-compression allowable feed speed for determination and the post-compression allowable feed speed for determination in step S7 will be described. Since the calculation method of the allowable feed speed before determination and the allowable feed speed after compression for determination is the same, in the following description, the calculation method of the allowable feed speed will be described and calculated based on the command path N (k). The allowable feed speed is the allowable feed speed before compression for determination, and the allowable feed speed calculated in the post-compression compression command path N ″ (h) is the allowable feed speed after compression for determination. Here, i−δ ≦ k ≦ i + δ (δ: number of prefetch command paths) and h ≦ j.

As a method for calculating the allowable feed speed, the following methods are generally known.
・ A circular arc passing through the three points is obtained, and a permissible feed speed that does not exceed a preset allowable maximum acceleration or allowable maximum torque is obtained from the calculated curvature of the arc.
The acceleration at the joint between the two command paths is obtained from the angle formed by the two command paths, and the allowable feed speed is determined so that the acceleration does not exceed a preset allowable maximum speed.
-The speed change of each axis in the two command paths is obtained, and the allowable feed speed is obtained so that the speed change does not exceed the preset allowable maximum speed change.

  In the above method, the allowable feed speed is obtained from the shape information of the local command path, but in order to grasp the shape of the command path and obtain the accurate allowable feed speed, a plurality of command paths are pre-read, A method is also known in which a curvature is obtained from several command paths, and a permissible feed speed that does not exceed a preset permissible maximum acceleration or permissible maximum torque is obtained from the obtained curvature.

In addition, since the actual tool trajectory differs from the command path due to servo system delay and motor characteristics, the estimated tool position, which is the actual tool position, is obtained using a transfer function based on the servo system delay and motor characteristics. A method for calculating an allowable feed speed based on the estimated tool position is also known. FIG. 4 is a flowchart showing an example of the processing flow of the allowable feed speed calculation method using a transfer function based on the delay of the servo system and the motor characteristics. First, a temporary command position P ₀ (i ₇ ) (i ₇ = 1, 2,..., N ₇ ) obtained by interpolating the command path output from the machining program reading unit 2 in step S71 at predetermined distance increments. create. Here, the predetermined distance increment is a preset value or a value Fδt obtained by multiplying the command feed speed F by the sampling period δt.

Next, in step S72, using the temporary command position P ₀ (i ₇ ), based on the transfer function from the command position considering the delay of the servo system and the motor characteristics to the estimated tool position that is the actual tool position. The tool estimated position P (i ₇ ) is calculated. FIG. 5 shows a temporary command position P ₀ (i ₇ ) and a tool estimated position P (i ₇ ) created by interpolating the command path represented by a solid line. An example of the transfer function H (z) for calculating the tool estimated position P is shown below.

Here, z is the Z transformer, m ₇ is the order of the transfer function, a _j7 and b _j7 (j ₇ = 0 to m ₇ ) are the numerator polynomial and denominator polynomial coefficient of the transfer function, which the actual system has It is determined by the delay of the servo system and the motor characteristics.

Next, in step S73, a feature amount representing a temporal change in the tool estimated position P (i ₇ ) calculated in step S72 is calculated. Wherein the normal component of the acceleration of the tool estimated position P (i ₇₎ as the feature amount An (i 7) _{(hereinafter,} referred to as the normal acceleration) is calculated. The normal acceleration An (i ₇ ) at the tool estimated position P (i ₇ ) is expressed by the following equation.

In the above equation, A (i ₇ ), V (i ₇ ), and u (i ₇ ) are an acceleration vector, a direction vector, and a unit direction vector at the estimated tool position P (i ₇ ), respectively. FIG. 6A shows a vector diagram representing a method of calculating the acceleration vector A (i ₇ ), and FIG. 6B shows a normal acceleration An (i ₇ ).

Finally, in step S74, the allowable feed speed Fd is obtained from the normal acceleration An (i ₇ ) calculated in step S73 and the preset allowable normal acceleration _Amax . The allowable feed speed Fd is given by the following equation.

Here, Fr is an allowable feed speed when the path can be regarded as a circular arc (hereinafter referred to as an arc allowable feed speed), and Fc is an allowable feed speed when the path can be regarded as a corner (hereinafter referred to as a corner allowable feed speed) F _0. Is a feed rate corresponding to the distance increment used in step S72. Cr (Cr> 0) and Cc (Cc> 0) are preset parameters (hereinafter referred to as an arc accuracy coefficient and a corner accuracy coefficient) for determining the accuracy with respect to an arc and a corner, for example, 0 <Cr If it is set to <1, more accurate machining can be performed with an arc, and if it is set to Cr> 1, higher speed machining can be realized with an arc.

In the above description, the allowable feed speed is obtained by using the normal acceleration as the feature quantity of the temporal change in the tool estimated position, but the allowable feed speed can be obtained by another feature quantity. For example, instead of the normal acceleration An (i ₇ ), the allowable feed speed can be obtained even if the acceleration A (i ₇ ) and jerk, which is a temporal change in acceleration, are used as the feature amount. Also, if you want to reduce striped scratches on the machined surface due to vibration-prone machines, use the estimated tool position, speed, acceleration, or vibration component of acceleration as a feature value, and allow based on each allowable value. You may find the feed rate.

  Further, since the interpolation allowable feed speed 19 that is finally used for interpolation is calculated again by the interpolation allowable feed speed calculation section 7, the determination allowable feed speed calculation section 3 may only calculate an approximate value of the allowable feed speed. . That is, the processing load of the determination allowable feed rate calculation unit 3 may be reduced by approximating a feature amount such as normal acceleration or a calculation formula of the allowable feed rate using the feature amount. Further, when prefetching a plurality of command paths and calculating the allowable feed speed based on the plurality of command paths, the predetermination command to be referred to when the judgment allowable feed speed calculation unit 3 calculates the judgment allowable feed speed. The processing load of the determination allowable feed speed calculation unit 3 may be reduced by making the number of paths smaller than the number of prefetch command paths referred to by the interpolation allowable feed speed calculation unit 7.

<< Explanation of whether compression is possible >>
Next, the process for determining whether or not compression is possible in step S8 will be described. FIG. 7 is a flowchart illustrating an example of the flow of compression determination processing performed by the compression determination unit 4.

  In step S81, using the pre-compression route correction / operation data read by the machining program reading unit 2, the route correction / operation data 17 of the post-compression command route N ′ (j) and the route correction of the command route N (i). -When the operation data 13 is different, or the post-compression command path N '(j) or the command path N (i) is a command path that requires deceleration stop at the end of the command path, or the post-compression command path When N ′ (j) or the command path N (i) is in the operation mode for decelerating and stopping at the end point of each command path, compression is not possible, and the compression impossible judgment is output to the compression processing unit 5. The command path that needs to be decelerated and stopped at the end point of the command path includes a positioning command (G00 command) and an exact stop command (G09 command, G61 command), and an operation mode for decelerating and stopping at the end point of each command path. Includes a single block operation mode in which command paths are executed one by one and an error detection mode in which a deceleration check is performed at the end point of each command path by inputting an external signal. In addition, as a method for determining whether or not compression is possible, when the number of compression paths (the number of command paths included in the post-compression command path) exceeds a predetermined maximum value, or a path error due to compression is determined in advance. When the error is exceeded, or the route length of the command route after compression exceeds a predetermined allowable length, or the cumulative route length of multiple command routes compressed into one route exceeds a predetermined value A method for determining that compression is not possible can be applied. Further, in the compression propriety determination in step S81, since the pre-determination allowable feed speed for determination and the post-compression allowable feed speed for determination are not used, the compression propriety determination in step S81 is performed before the allowable feed speed calculation unit 3, If it is determined in step S81 that compression is not possible, the processing load in the compression process may be reduced by not performing the process of the allowable feed speed calculation unit 3. If it is not determined in step S81 that compression is not possible, the process proceeds to step S82.

  In step S82, the pre-determination permissible pre-compression feed speed calculated by the judgment permissible feed speed calculation unit 3 is compared with the command feed speed (F command) commanded by the machining program, and the smaller of the two values. Is calculated as a pre-compression tool command feed speed for determination. Further, the post-compression allowable feed speed calculated by the determination allowable feed speed calculation unit 3 is compared with the command feed speed (F command) commanded by the machining program, and the smaller one of the values is determined. The post-compression tool command feed speed is calculated, and the process proceeds to step S83.

  In step S83, when the pre-compression tool command feed speed for determination calculated in step S82 is equal to the corner allowable feed speed in the command path, that is, the corner allowable feed speed in the pre-compression shape is the arc allowable feed in the pre-compression shape. When the value is smaller than the speed and the command feed speed (F command), the compression is impossible, and the compression impossible determination is output to the compression processing unit 5. If it is not determined in step S83 that compression is not possible, the process proceeds to step S84.

  In step S84, when the post-compression tool command feed speed for determination calculated in step S82 is equal to the allowable corner feed speed in the post-compression shape, that is, the allowable corner feed speed in the post-compression shape is equal to the allowable arc in the post-compression shape. When the value is smaller than the feed speed and the command feed speed (F command), the compression is impossible, and the compression impossible judgment is output to the compression processing unit 5. If it is not determined in step S84 that compression is not possible, the process proceeds to step S85.

  In the description of step S83 and step S84, the allowable corner feed speed determined by the corner accuracy coefficient Cc is the compressible feed speed, and the tool command feed speed for determination or the post-compression tool command feed speed for determination is the corner allowable speed. When it becomes equal to the feed rate, it is determined that compression is impossible, but the compressible feed rate may be set in advance. The compressible feed speed may be determined from other parameters.

  In step S85, the pre-compression tool command feed speed for determination and the post-compression tool command feed speed for determination are compared, and the difference between the pre-compression tool command feed speed for determination and the post-compression tool command feed speed for determination is set in advance. If it is equal to or greater than the maximum feed rate change amount, compression is impossible, and a compression impossible determination is output to the compression processing unit 5. In the above description, the pre-compression tool command feed speed for judgment and the post-compression tool command feed speed for judgment are directly compared, but the actual tool position is from the command position taking into account the delay of the servo system, motor characteristics, etc. Using the transfer function up to the estimated tool position, the pre-compression tool estimated trajectory Pb, which is the trajectory of the tool when the tool moves at the pre-decompression tool command feed speed for judgment, and the post-compression command path are compressed for judgment. The post-compression tool estimated trajectory Pa, which is the trajectory of the tool when the tool moves at the post-tool command feed speed, is calculated, and the path error between the pre-compression tool estimated trajectory Pb and the post-compression tool estimated trajectory Pa is a preset maximum trajectory error. When it becomes above, it may be determined that compression is impossible. Furthermore, the comparison between the pre-compression tool command feed speed for determination and the post-compression tool command feed speed for determination and the comparison between the pre-compression tool estimated trajectory Pb and the post-compression tool estimated trajectory Pa are performed. The difference between the tool command feed speed and the post-compression tool command feed speed for determination is equal to or greater than a preset maximum feed speed change amount, or the path error between the pre-compression tool estimated path Pb and the post-compression tool estimated path Pa is It may be determined that compression is not possible when the set maximum trajectory error is exceeded.

  In the above description, it has been explained that the allowable feed speed at the command point which is the start point / end point in each command path is obtained, and whether or not compression is possible is determined based on the allowable feed speed at the command point. In the curve shape such as G02, G03 command), the allowable feed speed for the entire command path is calculated. Therefore, compression similar to the determination of whether or not compression is possible based on the allowable feed speed at the command point is performed based on the allowable feed speed for the entire command path. You may determine whether it is possible.

  Further, in the first embodiment, as described above, the determination of whether or not compression is possible is performed by (1) determining whether or not compression is possible based on path correction / operation data or the like, (2) determining whether or not compression is possible based on a pre-compression tool command feed speed for determination, (3 This is performed by performing four determinations: compression determination based on a post-compression tool command feed speed for determination, and (4) compression determination based on a comparison between a pre-compression tool command feed speed for determination and a post-compression tool command feed speed for determination. However, only one or a plurality of compression propriety determinations among the above four compression propriety determinations may be performed.

<Operation of moving data creation unit>
The movement data creation unit 6 corrects the post-compression command path 16 created by the compression processing unit 5 to a tool movement path based on the post-compression path correction / operation data 17. This correction includes translation such as tool length offset and workpiece offset, enlargement / reduction of the entire command path, and coordinate conversion such as coordinate rotation. FIG. 8 is a diagram illustrating an example of the relationship between the post-compression command path and the tool movement path in the first embodiment. Subsequently, the movement data creation unit 6 creates tool movement data 18 necessary for interpolation on the tool movement path whose path has been corrected. The tool movement data 18 is a tool movement path and movement data necessary for interpolation. Specifically, the start point and end point of each axis for determining the tool position, the path length from the start point to the end point, the tool movement path Information necessary for determining the operation of the machine tool, such as a unit direction vector and a command feed speed, is included.

  By using the post-compression command path 16, the movement data creation section 6, the interpolation allowable feed speed calculation section 7, and the interpolation processing section 8 are performed, so that the movement data creation section 6, the interpolation allowable feed speed calculation section 7, and the interpolation processing section. 8 processing time can be shortened. Specifically, when the number of compression paths (the number of command paths included in the post-compression command path) is n, the tool position is not compressed from the post-compression command path 16 and the post-compression path correction / operation data 17. 1 / n of the processing time.

<Operation of the allowable feed speed calculation unit for interpolation>
The interpolation allowable feed speed calculation unit 7 calculates an interpolation allowable feed speed 19 based on the tool movement data 18 created by the movement data creation unit. The method of calculating the interpolation allowable feed speed 19 is the same as the pre-determination allowable feed speed for determination and the post-compression allowable feed speed calculated by the determination allowable feed speed calculation unit 3.

<Operation of interpolation processing unit>
The interpolation processing unit 8 interpolates on the tool movement path using the tool movement data created by the movement data creation unit 6 and the allowable feed speed 19 for interpolation calculated by the interpolation allowable feed speed calculation unit 7, Create position 20.

  FIG. 9 is a flowchart showing an example of the processing flow of the interpolation processing unit 8 in the first embodiment. Hereinafter, a description will be given with reference to FIG. Nt ′ (j) is the tool movement path obtained by correcting the jth post-compression command path N ′ (j), and the tool path length (distance from the start point to the end point) of the tool movement path Nt ′ (j) is Lt ′. (J).

In step S801, the smaller of the allowable feed speed 19 for interpolation calculated by the allowable feed speed calculator for interpolation 19 and the command feed speed commanded by the machining program is set as the tool command feed speed _Ft , and the tool command feed. A movement amount F _t ΔT per interpolation cycle is obtained from the speed F _t .

At step S802, the determined tool movement path Nt '(j) the movement amount per interpolation period from the current tool position pt ₀ on _{F t} of ΔT advanced tool position pt when the tool movement path Nt' (m). A method of calculating the tool movement path Nt ′ (m) with the tool position pt will be described with reference to FIG. Here, for simplicity, it is assumed that the current tool position pt ₀ is at the start point of the tool movement path Nt ′ (j). First, in step S802, it is determined whether or not the movement amount F _t ΔT is larger than the tool path length Lt ′ (j). When the movement amount F _t ΔT is smaller than the tool path length Lt ′ (j), the tool position pt is on the tool movement path Nt ′ (j). On the other hand, when the movement amount F _t ΔT is larger than the tool movement path Nt ′ (j), the movement amount F _t ΔT ′ obtained by subtracting the tool path length Lt ′ (j) from the movement amount F _t ΔT per interpolation period A size comparison with the tool path length Lt ′ (j + 1) is performed. When the subtracted movement amount F _t ΔT ′ is smaller, the tool position pt is on the tool movement path Nt ′ (j + 1). By repeating the above, the tool movement path Nt ′ (m) with the tool position pt can be obtained. Hereinafter, the tool movement path with the tool position pt is defined as Nt ′ (m). In the above example, the current tool position pt ₀ is calculated as being at the start point of the tool movement path Nt ′ (j), but the current tool position pt ₀ is not at the start point of the tool movement path Nt ′ (j). In this case, the remaining path length of the tool movement path Nt ′ (j) having the current tool position pt ₀ (the length from the current tool position to the end point of the tool movement path Nt ′ (j)) is set to Lt ′ ( j), the tool movement path Nt ′ (m) with the tool position pt can be obtained in the same procedure as described above.

In step S803, the tool position pt is obtained. Assuming that the starting point coordinate value of the tool movement path Nt ′ (m) is p (m−1), the tool position pt is set to the starting point coordinate value p (m−1) and the tool movement path Nt ′ as shown in Expression (4). It is represented by the sum of the movement amount F _t ΔT ′ from the start point of (m).

  The tool position pt is obtained by the above equation (4), and this is output as the tool position 20. In the first embodiment, the machining program reading unit 2, the determination allowable feed rate calculation unit 3, the compression availability determination unit 4, the compression processing unit 5, the movement data creation unit 6, the interpolation allowable feed rate calculation unit 7, Although the case where the interpolation processing unit 8 is provided in the same device has been described, the above units may be provided in different devices. For example, the processing program reading unit 2, the determination allowable feed speed calculation unit 3, the compression availability determination unit 4, the compression processing unit 5, and the newly compressed command path 16 and the post-compression path correction / operation data 17 are stored as compressed data. Using the apparatus provided with the post-compression data storage unit stored in the storage unit, the post-compression command path 16 and the post-compression path correction / operation data 17 stored in the post-compression data storage unit, and the allowable data for interpolation. You may divide into the apparatus which processes the speed calculation part 7 and the interpolation process part 8. FIG.

<Effect>
As described above, according to the first embodiment, the pre-determination allowable feed rate for determination or / and the post-compression allowable feed rate for determination are obtained before the compression processing unit 5, and the pre-determination allowable feed rate before compression or Since the determination of whether or not compression is possible is performed based on the post-compression allowable feed speed and the command feed speed for determination, it is possible to prevent a change in the feed speed of the tool with respect to the workpiece due to the compression. In other words, by calculating the allowable feed speed before compression and determining whether or not compression is possible based on the allowable feed speed, it is possible to prevent changes in the allowable feed speed due to compression, and to perform high-speed machining while maintaining machining accuracy. Can be realized. (In the conventional compression determination, whether or not compression is possible is determined based on local shape data, and whether or not compression is possible is not determined based on the feed speed. Since the tolerance is constant even when the command feed speed is changed, the compression is determined. The range did not change, and the compression judgment corresponding to the command feed speed could not be made.)

  Specifically, in the first embodiment, the pre-determination permissible pre-compression feed speed and the post-determination permissible post-compression permissible feed speed and the command feed speed whichever is smaller are determined as the pre-determination tool command feed speed and the post-determination tool command after compression. (2) Compressibility determination based on pre-compression tool command feed speed for determination, (3) Determination of compression propriety using the pre-compression tool command feed speed for determination and post-compression tool command feed speed for determination, (3) ) Determination of whether or not compression is possible based on the post-compression tool command feed speed for determination. (4) Determination of whether or not compression is possible by comparing the pre-compression tool command feed speed for determination and the post-compression tool command feed speed for determination.

  In the first embodiment, in (2) compression determination based on the pre-compression tool command feed speed for determination, compression is not possible when the corner allowable feed speed before compression is smaller than the curve allowable feed speed and the command feed speed. Therefore, as shown in FIG. 12 (a), compression is impossible at a position where the acceleration such as the corner is high (command position P2), so that the corner is prevented from being deformed by compression as shown in FIG. 12 (b). can do. That is, the corner angle of the command position P2 does not change in the post-compression command path, and it is possible to prevent the post-compression allowable feed speed for interpolation from increasing due to compression and the shift of the position decelerated by the allowable feed speed for interpolation from shifting. Deterioration of processing accuracy can be prevented. Even when the command feed rate is changed, it is possible to determine whether or not compression is possible according to the changed command feed rate.

  That is, according to the first embodiment, in the compression possibility determination unit, the pre-determination allowable feed rate calculated by the determination allowable feed rate calculation unit is equal to or lower than a preset compressible feed rate. In this case, compression is impossible, and compression is not possible in areas where the allowable feed speed is low (the change in the slope of the line segment is large), such as corners, and the change in the slope of the line segment is small due to compression. Thus, high-accuracy machining can be realized by preventing the allowable feed speed from becoming higher than before compression. Further, in the compression possibility determination unit, compression is disabled only when the pre-compression allowable feed rate calculated by the determination allowable feed rate calculation unit is equal to or less than the command feed rate commanded by the machining program. If the command feed rate is lower than the allowable feed rate, the tool will move at the command feed rate, and the tool feed rate will not change due to compression. By enabling compression, the compression effect can be improved and high-speed machining can be realized.

  Further, (3) in the determination of whether or not compression is possible based on the post-compression tool command feed speed for determination, compression is impossible when the corner allowable feed speed after compression is smaller than the curve allowable feed speed and the command feed speed. As shown in a), N1, N2, N3 and N4, N5 are compressed even though the command paths N1, N2, N3, N4, and N5 are smooth curves, as shown in FIG. In addition, since the compressed command paths N′1 and N′2 are compressed, the change in the inclination of N′1 and N′2 increases, and the allowable feed speed for interpolation at the command position P3 becomes smaller than necessary. This can prevent the deterioration of processing accuracy.

  That is, according to the first embodiment, in the compressibility determination unit, the post-compression allowable feed rate calculated by the determination allowable feed rate calculation unit is equal to or lower than a preset compressible feed rate. In this case, if compression is disabled, the change in the slope of the line segment increases due to compression and the allowable feed speed after compression decreases. High-precision machining can be realized. Further, in the compressibility determination unit, compression is disabled only when the post-compression allowable feed rate calculated by the determination allowable feed rate calculation unit is equal to or less than the command feed rate commanded by the machining program. If the command feed rate is lower than the allowable feed rate, the tool will move at the command feed rate, and the tool feed rate will not change due to compression. By enabling compression, the compression effect can be improved and high-speed machining can be realized.

  Further, (4) in the determination of whether or not compression is possible by comparing the pre-compression tool command feed speed for determination and the post-compression tool command feed speed for determination, the difference between the pre-compression tool command feed speed for determination and the post-compression tool command feed speed for determination is If compression is disabled when the amount is greater than the preset maximum feed rate change amount, the change in interpolation feed rate due to compression can be made less than the maximum feed rate change amount, resulting in deterioration of machining accuracy due to compression. Can be prevented. That is, by performing compression only within a range in which the determination tool command feed speed does not change significantly before and after compression, variation in the tool command feed speed due to compression can be suppressed and high-precision machining can be realized.

  When the command path 12 is moved at the pre-compression tool command feed speed for determination, the pre-compression tool estimated trajectory, which is the estimated trajectory of the tool, and the post-compression command path 16 is moved at the post-compression tool command feed speed for determination. If the trajectory error of the post-compression estimated tool trajectory, which is the estimated trajectory of the tool, is greater than or equal to the preset maximum trajectory error, compression is disabled. It is also possible to make the error less than the maximum trajectory error. In other words, high-precision machining can be realized by predicting actual tool paths on the command path and post-compression command path and performing compression only within a range in which the amount of change in the tool path is within a predetermined value before and after compression. it can.

  In the first embodiment, the compressibility determination unit determines that the cumulative path length of the plurality of command paths compressed into one path is larger than the movement amount per unit time at the command feed speed, or the compressed command. When the number of routes exceeds a predetermined value, compression may be disabled. By adopting such a configuration, it is possible to prevent the command path from being compressed more than necessary by providing the cumulative path length after compression and the maximum value of the compressed line segment, and to prevent deterioration in accuracy due to compression. .

  Further, the compression possibility determination unit may make compression impossible when the machining condition is changed by the machining program. By adopting such a configuration, it is possible to prevent a command path having different machining conditions such as a command speed and a spindle speed from being compressed into one post-compression command path, and prevent a machining condition from changing before and after compression. Can do.

Embodiment 2. FIG.
A second embodiment of a production system provided with a numerical control device according to the present invention will be described below with reference to the drawings. The present invention is not limited to the second embodiment. FIG. 11 is a block diagram showing a schematic configuration of the second embodiment of the production system provided with the numerical control device according to the present invention. In FIG. 11, the compression apparatus 101 includes a post-compression command path 16 and a post-compression path correction / operation data 17 output from the compression processing section 5, a post-compression data storage section 9 that stores the post-compression data buffer 10, and a processing program read. Unit 2, determination allowable feed speed calculation unit 3, compression possibility determination unit 4, and compression processing unit 5. On the other hand, the numerical control device 100 includes a movement data creation unit 6, an interpolation allowable feed speed calculation unit 7, and an interpolation processing unit 8. In addition, the same number is attached | subjected to the component which achieves the same function as the component of the block diagram which shows the schematic block diagram of the numerical control apparatus in Embodiment 1 shown in FIG. 1, and the overlapping description is abbreviate | omitted.

  Next, the operation of the second embodiment will be described. In the first embodiment, the machining program reading unit 2, the determination allowable feed rate calculation unit 3, the compression availability determination unit 4, the compression processing unit 5, the movement data creation unit 6, the interpolation allowable feed rate calculation unit 7, the interpolation in FIG. Whereas the processing unit 8 is all provided in the numerical control device 100, in the second embodiment, the machining program reading unit 2, the determination allowable feed speed calculation unit 3, the compressibility determination unit 4, the compression processing unit in FIG. 5. The compression apparatus 101 including the post-compression data storage unit 9 stores the post-compression command path 16 and post-compression path correction / operation data 17 in the post-compression data buffer before processing. In the numerical controller 100 including the movement data creation unit 6, the interpolation allowable feed speed calculation unit 7, and the interpolation processing unit 8, the post-compression command path 16 and the post-compression path correction / operation data 17 stored in the post-compression data buffer are used. The tool position 20 is output.

  In the second embodiment, the compression program 101 including the machining program reading unit 2, the determination allowable feed speed calculation unit 3, the compression availability determination unit 4, the compression processing unit 5, and the post-compression data storage unit 9 and movement data creation are provided. Although the numerical control device 100 has been described as including the unit 6, the allowable feed speed calculation unit 7 for interpolation, and the interpolation processing unit 8, the processing of the movement data creation unit 6 may also be performed by the compression device. In this case, the compression device includes a tool movement data storage unit that includes tool movement data in a tool movement data buffer.

  In addition to the movement data creation unit 6, the processing of the interpolation allowable feed speed calculation unit 7 may be performed by the compression device. In this case, the compression apparatus includes a tool interpolation data storage unit that stores the tool movement data and the allowable feed rate for interpolation in the tool interpolation data buffer.

  As described above, the numerical control device and the production system according to the present invention are useful when applied to a numerical control device that numerically controls a machine tool or a production system that includes a numerical control device. By replacing (compressing) the command path with one command path, the present invention is optimally applied to a numerical control device that realizes high-speed machining or a production system equipped with a numerical control device.

DESCRIPTION OF SYMBOLS 1 Machining program 2 Machining program reading part 3 Judgment allowable feed speed calculation part 4 Compression determination part 5 Compression processing part 6 Movement data creation part 7 Allowable feed speed calculation part for interpolation 8 Interpolation process part 9 Data storage part after compression 10 Compression Post-data buffer 11 Program instruction 12 Command path 13 Pre-compression path correction / motion data 14 Allowable feed speed for determination 15 Compression result determination result 16 Post-compression command path 17 Path correction / motion data 18 Tool movement data 19 Allowable feed speed for interpolation 20 Tool position 100 Numerical control device 101 Compression device

Claims (18)

In a numerical control device that creates a post-compression command path obtained by compressing a plurality of continuous command paths into one path, and controls the machine tool based on the post-compression command path.
The numerical control device includes a determination allowable feed rate calculation unit, a compression propriety determination unit, a compression processing unit, and an interpolation allowable feed rate calculation unit,
The determination allowable feed speed calculation unit calculates a pre-compression allowable feed speed or / and a post-compression allowable feed speed from the command path or / and the post-compression command path,
The compression propriety determination unit determines whether or not compression is possible based on the allowable feed speed before compression for determination or / and the allowable feed speed after compression for determination,
The compression processing unit creates a post-compression command path obtained by compressing the plurality of consecutive command paths into one path when the compressibility determination result of the compressibility determination section is compressible.
The numerical control device, wherein the interpolation allowable feed speed calculation unit calculates an interpolation allowable feed speed from the post-compression command path.   The compressibility determination unit determines that compression is not possible when the pre-determination allowable compression rate calculated by the determination allowable feed rate calculation unit is equal to or lower than a preset compressible feed rate. The numerical control apparatus according to claim 1, wherein   The compressibility determination unit determines that compression is not possible when the pre-determination allowable feed rate calculated by the determination allowable feed rate calculation unit is equal to or less than a command feed rate commanded by a machining program. The numerical control apparatus according to claim 2, wherein   The compressibility determination unit determines that compression is not possible when the post-compression allowable feed rate calculated by the determination allowable feed rate calculation unit is equal to or lower than a preset compressible feed rate. The numerical control apparatus according to claim 1, wherein   The compressibility determination unit determines that compression is not possible when the post-compression allowable feed rate calculated by the determination allowable feed rate calculation unit is equal to or less than a command feed rate commanded by a machining program. The numerical control device according to claim 4, wherein   The compression propriety determination unit determines a smaller one of the pre-determination allowable feed rate and the command feed rate calculated by the determination allowable feed rate calculation unit as a pre-decompression tool command feed rate for determination, and the determination The smaller one of the allowable post-compression allowable feed speed and the command feed speed calculated by the allowable feed speed calculation unit is set as a post-compression tool command feed speed for determination, and the pre-compression tool command feed speed for determination 6. The compression according to claim 1, wherein compression is impossible when the difference in the post-compression tool command feed speed is greater than or equal to a preset maximum feed speed change amount. 6. Numerical control unit.   The compression propriety determination unit determines a smaller one of the pre-determination allowable feed rate and the command feed rate calculated by the determination allowable feed rate calculation unit as a pre-decompression tool command feed rate for determination, and the determination The smaller one of the allowable post-compression feed speed and the command feed speed is used as the post-compression tool command feed speed for judgment, and the tool is moved at the pre-compression tool command feed speed for judgment and the post-compression tool command feed speed for judgment. Each pre-compression tool estimated trajectory and post-compression tool estimated trajectory in the case of control is obtained, and if the trajectory error between the pre-compression tool estimated trajectory and the post-compression tool estimated trajectory is greater than or equal to a preset maximum trajectory error, compression is performed. The numerical control device according to claim 2, wherein the numerical control device is disabled.   The compressibility determination unit determines that the path length of a plurality of command paths compressed into one path is larger than the movement amount per unit time at the command feed speed, or the number of compressed command paths exceeds a predetermined value. The numerical control device according to claim 1, wherein compression is impossible.   The numerical control device according to any one of claims 1 to 7, wherein the compressibility determination unit prohibits compression when a processing condition is changed by a processing program. In a production system that creates a post-compression command path by compressing a plurality of continuous command paths into one path, and controls the machine tool based on the post-compression command path.
The production system includes a determination allowable feed rate calculation unit, a compression determination unit, a compression processing unit, a compression unit including a post-compression data storage unit, and a numerical controller including an interpolation allowable feed rate calculation unit,
The determination allowable feed speed calculation unit calculates a pre-compression allowable feed speed or / and a post-compression allowable feed speed from the command path or / and the post-compression command path,
The compression propriety determination unit determines whether or not compression is possible based on the allowable feed speed before compression for determination or / and the allowable feed speed after compression for determination,
The compression processing unit creates a post-compression command path in which the plurality of consecutive command paths are compressed into one path when the compressibility determination result in the compressibility determination section is compressible.
The post-compression data storage unit stores the post-compression command path in a post-compression data buffer,
The allowable interpolation feed speed calculation unit calculates an allowable interpolation feed speed from the post-compression command path stored in the post-compression data buffer.   The compressibility determination unit determines that compression is not possible when the pre-determination allowable compression rate calculated by the determination allowable feed rate calculation unit is equal to or lower than a preset compressible feed rate. The production system according to claim 10, wherein the production system is characterized.   The compressibility determination unit determines that compression is not possible when the pre-determination allowable feed rate calculated by the determination allowable feed rate calculation unit is equal to or less than a command feed rate commanded by a machining program. The production system according to claim 11, wherein the production system is characterized.   The compressibility determination unit determines that compression is not possible when the post-compression allowable feed rate calculated by the determination allowable feed rate calculation unit is equal to or lower than a preset compressible feed rate. The production system according to claim 10, wherein the production system is characterized.   The compression propriety determination unit makes compression impossible only when the post-compression allowable feed rate calculated by the determination allowable feed rate calculation unit is equal to or less than a command feed rate commanded by a machining program. The production system according to claim 13.   The compression propriety determination unit determines a smaller one of the pre-determination allowable feed rate and the command feed rate calculated by the determination allowable feed rate calculation unit as a pre-decompression tool command feed rate for determination, and the determination The smaller one of the allowable post-compression allowable feed speed and the command feed speed calculated by the allowable feed speed calculation unit is set as a post-compression tool command feed speed for determination, and the pre-compression tool command feed speed for determination The compression according to any one of claims 10 to 14, wherein compression is impossible when the difference in the post-compression tool command feed speed is equal to or greater than a preset maximum feed speed change amount. Production system.   The compression propriety determination unit determines a smaller one of the pre-determination allowable feed rate and the command feed rate calculated by the determination allowable feed rate calculation unit as a pre-decompression tool command feed rate for determination, and the determination The smaller one of the allowable post-compression feed speed and the command feed speed is used as the post-compression tool command feed speed for judgment, and the tool is moved at the pre-compression tool command feed speed for judgment and the post-compression tool command feed speed for judgment. Each pre-compression tool estimated trajectory and post-compression tool estimated trajectory in the case of control is obtained, and if the trajectory error between the pre-compression tool estimated trajectory and the post-compression tool estimated trajectory is greater than or equal to a preset maximum trajectory error, compression is performed. The production system according to any one of claims 11 to 15, wherein the production system is disabled.   The compressibility determination unit determines that the path length of a plurality of command paths compressed into one path is larger than the movement amount per unit time at the command feed speed, or the number of compressed command paths exceeds a predetermined value. The production system according to any one of claims 10 to 16, wherein compression is impossible.   The production system according to any one of claims 10 to 16, wherein the compressibility determination unit prohibits compression when a processing condition is changed by a processing program.

Images