阅读说明：本技术 加工时间预测装置 (Machining time prediction device ) 是由 森崎和彦 于 2019-09-05 设计创作，主要内容包括：本发明提供一种加工时间预测装置,其针对每个程序块计算在由NC指令指定的工具路径上进行移动所需要的时间。加工时间预测装置将上述NC指令分割为程序块,将上述工具路径分割为段,针对每个上述段计算段移动时间,保存上述程序块与上述段之间的对应关系。加工时间预测装置还针对每个上述程序块累计上述段来计算程序块移动时间,在上述NC指令的编辑画面中将上述程序块与上述程序块移动时间对应起来进行显示。(The invention provides a machining time prediction device which calculates the time required for moving on a tool path specified by an NC command for each block. The machining time prediction device divides the NC command into blocks, divides the tool path into segments, calculates a segment movement time for each segment, and stores a correspondence relationship between the blocks and the segments. The machining time prediction device may further calculate a block moving time by integrating the segments for each block, and display the block and the block moving time in association with each other on an edit screen of the NC command.)

1. A machining time prediction device for calculating, for each block, a time required for movement on a tool path specified by an NC command,

the machining time prediction device includes:

an NC command decoding unit that divides the NC command into blocks;

a segment data generating unit that divides the tool path into segments;

a segment moving time calculation unit that calculates a segment moving time for each of the segments;

a storage unit for storing a correspondence between the program block and the segment; and

and a block move time calculation unit that calculates a block move time by integrating the segments for each block, and displays the block in association with the block move time on the NC-instructed editing screen.

2. The processing time prediction apparatus according to claim 1,

the block move time calculation unit displays the block move time at the head of a line of a program text of the block on the NC-instructed editing screen.

3. The processing time prediction apparatus according to claim 1 or 2,

the block move time calculation unit displays a background color of the scroll bar at a position corresponding to the block in a display color corresponding to the block move time on the NC-instructed editing screen.

4. The machining time prediction apparatus according to any one of claims 1 to 3,

the block move time calculation unit displays a list in which the blocks are associated with the block move time, and when any one of the blocks is selected from the list, the block move time calculation unit transitions to an editing screen of the selected block.

Technical Field

The present invention relates to a machining time prediction apparatus, and more particularly, to a machining time prediction apparatus capable of easily visually confirming a result of prediction of a machining time for each block.

Background

When a Numerical Control (NC) program is created and modified, it is sometimes necessary to check a machining time of the NC program. In particular, it is required to specify how much time it takes to determine which part in the NC program.

Conventionally, as one of methods for checking the machining time of an NC program, there is a method for operating an NC program by actually operating an industrial machine (hereinafter simply referred to as a machine) including a machine tool. As another method, there is a method using software for predicting the machining time of an NC program.

As an example of the latter method, there is a method described in the following patent document. U.S. Pat. No. 8843230 discloses an apparatus for calculating a moving speed of a tool according to various conditions and predicting a machining time based on the moving speed of the tool. U.S. Pat. No. 9836044 discloses a device that divides an NC program into a plurality of sections (block groups) and predicts a machining time only in a section in which a program text is corrected, thereby reducing the time required for the correction process. U.S. patent application publication No. 2017/0227952 discloses an apparatus for predicting a processing time in units of necessary blocks. U.S. patent application publication No. 2017/0242408 discloses an apparatus for predicting a processing time in units of segments.

The general operator repeats 2 tasks of "creation or modification of an NC program" and "checking a machining time of the program" to optimize the NC program. Specifically, the operator repeats the following operations: visually confirming which part of the generated or corrected program text requires a certain amount of processing time, and performing re-correction as necessary. Therefore, if the operator can easily visually recognize the correspondence between the program text and the processing time, the work performed by the operator can be made efficient.

However, in the method described in the above patent document, even if the total machining time before and after the NC program correction can be compared, it is difficult to visually confirm which portion takes how much time. Therefore, for example, a work load for searching for a portion that takes a large amount of processing time within the NC program increases.

In the method described in the above patent document, the operator checks the machining time and edits the NC program on different screens. Therefore, the operation flow performed by the operator is interrupted, and the operability is degraded.

Disclosure of Invention

The present invention has been made to solve the above-described problems, and an object thereof is to provide a machining time prediction apparatus in which an operator can easily visually recognize a result of prediction of a machining time for each block.

A machining time prediction device according to the present invention calculates, for each block, a time required for movement on a tool path specified by an NC command, and includes: an NC command decoding unit that divides the NC command into blocks; a segment data generating unit that divides the tool path into segments; a segment moving time calculation unit that calculates a segment moving time for each of the segments; a storage unit for storing a correspondence between the program block and the segment; and a block move time calculation unit that calculates a block move time by integrating the segments for each block, and displays the block in association with the block move time on an edit screen of the NC command.

In the machining time prediction device according to an embodiment of the present invention, the block move time calculation unit displays the block move time at the head of a line of a program text of the block on the edit screen of the NC command.

In the machining time prediction device according to an embodiment of the present invention, the block move time calculation unit displays a background color of the scroll bar at a position corresponding to the block in an edit screen of the NC command by a display color corresponding to the block move time.

In the machining time prediction device according to an embodiment of the present invention, the block moving time calculation unit displays a list in which the blocks are associated with the block moving time, and when any one of the blocks is selected from the list, the block moving time calculation unit transitions to an editing screen of the selected block.

The present invention can provide a machining time prediction device in which an operator can easily visually recognize the result of prediction of the machining time for each block.

Drawings

The above and other objects and features of the present invention will become apparent from the following description of the embodiments with reference to the accompanying drawings. In the drawings:

fig. 1 shows an example of a hardware configuration of a machining time prediction apparatus according to an embodiment of the present invention.

Fig. 2 shows an example of a functional configuration of a machining time prediction device according to an embodiment of the present invention.

Fig. 3 shows an example of the storage contents of the block moving time storage unit shown in fig. 2.

Fig. 4 shows a display example of the block moving time of the machining time prediction apparatus according to the embodiment of the present invention.

Detailed Description

The machining time prediction apparatus 1 of the present embodiment predicts the machining time with the same configuration as that of the machining time prediction apparatus described in U.S. patent No. 8843230. That is, the machining time prediction apparatus 1 divides the tool path into minute segments called segments, and obtains a velocity profile indicating a velocity change in the tangential direction from the start point to the end point of the segment. Then, the machining time prediction apparatus 1 calculates the time required for the tool to move in the segment as the tool moves according to the obtained speed profile. The time required for the tool to move through the tool path is given by the sum of the movement times of each segment. The machining time prediction apparatus 1 determines a speed profile by taking a limit for speed determined based on a speed difference, a difference in acceleration, a difference in jerk, a curvature of a tool path, and the number of pieces of data used for speed calculation between adjacent pieces, thereby improving the accuracy of the calculated machining time. The machining time prediction apparatus 1 can deal with the movement of the tool as a unitary problem of dealing with the tangential velocity without decomposing the movement into movements of the respective axes, and therefore can shorten the processing time. The machining time prediction apparatus 1 can change the segment division interval, and can adjust the predicted value of the travel time and the accuracy of the predicted value.

The machining time prediction apparatus 1 newly provides a device or the same kind of means for predicting the machining time for each block, and a device or the same kind of means for displaying the predicted machining time for each block so that the operator can easily visually recognize the predicted machining time.

Fig. 1 is a schematic hardware configuration diagram showing main components of a machining time prediction apparatus 1 according to the present embodiment. The machining time prediction apparatus 1 is, for example, a numerical controller that controls a machine. Alternatively, the machining time prediction apparatus 1 may be an information processing apparatus such as a PC (personal computer) used for generating and correcting an NC program or predicting a machining time.

The machining time prediction apparatus 1 includes a Central Processing Unit (CPU)101, a ROM102 as a read only memory, a RAM103 as a random access memory, a nonvolatile memory 104, a bus 105, and an interface 106. The interface 106 is connected to an input/output device 107.

The CPU101 is a processor that controls the entire machining time prediction apparatus 1. The CPU101 reads out a system program stored in the ROM12 via the bus 105, and controls the entire machining time prediction apparatus 1 in accordance with the system program.

The ROM102 stores a system program in advance.

The RAM103 temporarily stores temporary calculation data, display data, data and programs input by an operator via the input/output device 107, and the like.

The nonvolatile memory 14 is supported by, for example, a battery not shown, and maintains a memory state even when the power supply of the machining time prediction apparatus 1 is turned off. The nonvolatile memory 104 stores data, programs, and the like input from the input/output device 107. Programs and data stored in the non-volatile memory 104 may be deployed in the RAM103 during execution and use.

The input/output device 107 is a device that includes a display device and an input device and inputs and outputs data, and typically includes a Manual Data Input (MDI) device, an operation panel, a touch panel, a display, a keyboard, a mouse, and the like. The input/output device 107 displays information received from the CPU101 via the interface 106 on a display device. The input/output device 107 transfers instructions, data, and the like input from the input device to the CPU101 via the interface 106.

Fig. 2 is a block diagram showing a schematic functional configuration of the machining time prediction apparatus 1. The machining time prediction apparatus 1 includes an NC command interpretation unit 10, a speed limit processing unit 20, a segment data generation unit 30, an intermediate memory (buffer) 40, a segment moving time calculation unit 50, and a total moving time calculation unit 60. The machining time prediction apparatus 1 further includes an ID storage unit 70 for storing an Identifier (ID), a block travel time calculation unit 80, and a block travel time storage unit 90. Among these, the ID storage section 70 is, more specifically, a block ID-segment ID storage section 70.

The NC-command interpretation unit 10 receives an NC command (machining program) 2 as an input, interprets the command data of each block described in the NC command (machining program) 2 and divides the interpreted command data into blocks to generate block data. The input NC command 2 may be in any form, such as a text file or binary data stored in a CNC program memory, as in the case of the input to a CNC (numerical control device).

The block data generated by the NC command decoding unit 10 indicates the command content of each block constituting the original NC command (machining program) 2. The block data includes position information of a start point and an end point of the block, a type of a path from the start point to the end point (a straight line, an arc, etc.), information for determining the path (a center position in the case of an arc, etc.), and speed information of a tool when moving on the block.

The speed limit processing section 20 includes a global speed limit processing section 21, a local speed limit processing section 22, and a data amount dependent speed limit processing section 23.

The global speed limit processing unit 21 compares a command speed Vc commanded by the NC command (machining program) 2 with a speed Via predetermined in accordance with the curvature of the tool path, and sets the smaller value as the upper limit speed Vlim. The data of the command velocity Vc and the curvature data of the tool path are based on the block data generated by the NC command interpretation unit 10. Data of the velocity Via predetermined in accordance with the curvature of the tool path is stored in a memory, not shown. When calculating the movement time of the tool in a state where the Speed magnification (Speed override) is applied, the command Speed Vc is replaced with a Speed obtained by multiplying the command Speed Vc by the ratio of the magnification. The local speed limit processing section 22 and the data amount dependent speed limit processing section 23 that use segment data are described later.

The segment data generating unit 30 receives the block data generated by the NC command interpreting unit 10, and divides the tool path from the start point to the end point of each block into segments. In this dividing method, a prescribed coefficient k or a coefficient determined according to the curvature of the tool path is multiplied by a command speed Vc to determine a dividing speed Vd, and segments are sequentially cut from the start of a block with a distance Vd · τ obtained by multiplying the dividing speed Vd by a prescribed time τ as a dividing interval. Each segment thus generated is a tiny fragment of the tool path. If the length of a segment is L, L can be expressed as Vd · τ. The predetermined time τ is set to the interpolation period or a time longer than it.

The cut-out minute pieces are accumulated (stored) as segment data in an intermediate memory (buffer) 40. The segment data stored (stored) in the intermediate memory 40 includes the length L of the segment, the direction of the segment (vector from the start point to the end point), the upper limit speed, and the angular velocity Vr obtained by the local velocity limit processing unit 22.

The local speed limit processing unit 22 obtains, for each segment generated by the segment data generation unit 30, the maximum speed among speeds at which the speed difference, the acceleration difference, and the jerk between adjacent segments converge to or below a preset allowable value. The obtained maximum velocity is set as the angular velocity Vr of the connection point of the adjacent segment. In addition, instead of considering the curvature of the tool path in the global velocity limit processing section 21, the curvature of the tool path may be considered in the local velocity limit processing section 22. The segment data having the set value is stored (stored) in the intermediate memory (buffer) 40.

The data-amount-dependent speed limit processing unit 23 is a device or another means for increasing the accuracy of the calculated machining time by adopting a limit for the tool movement speed determined according to the number of segment data. This is a processing unit provided in the machining time prediction device for reproducing: the speed limit is determined according to the amount of data read by the pre-read process.

The data-amount-dependent speed limit processing unit 23 sets the end point of the last segment (the last segment generated) stored in the intermediate memory (buffer) 40 to a predetermined speed Ua, and forms a speed curve u (t) indicating a speed change called a deceleration curve toward the first segment of the intermediate memory (buffer) 40. Since the tool cannot move at a speed equal to or higher than the speed curve u (t), u (t) is referred to as an allowable speed. Normally, the predetermined speed Ua is set to 0, but may be a finite value.

The segment moving time calculation unit 50 fetches one segment data from the head of the intermediate memory (buffer) 40, and calculates the time required for moving the segment. When the length of a segment is L, the time at the start of the segment is 0, and a velocity curve, which is the moving velocity of the tool at time T, is v (T), the time T required for moving any one segment satisfies the following equation. In the following formula, the velocity profile v (t) represents the time derivative of the distance s (t) measured along the tool path.

The total travel time calculation unit 60 integrates the travel times of the respective sections to obtain a total travel time.

In the present embodiment, the NC command interpretation unit 10 stores a block Identifier (ID) that can uniquely identify a block in the block ID-piece ID storage unit 70. The segment data generating unit 30 stores a segment Identifier (ID) that uniquely identifies a segment in the block ID-segment ID storage unit 70 in association with a block ID of a segment division source. The segment moving time calculation unit 50 outputs the calculated segment moving time to the block moving time calculation unit 80 together with the segment ID.

The block moving time calculation unit 80 sequentially acquires the segment moving time and the segment ID output from the segment moving time calculation unit 50. The block moving time calculation unit 80 refers to the block ID-segment ID storage unit 70 to specify the block ID corresponding to the segment ID, and accumulates the segment moving time in units of block IDs. This cumulative value is referred to as a block movement time. The block moving time calculation unit 80 stores the block moving time in the block moving time storage unit 90 in association with the block ID. The block migration time calculation unit 80 stores the total number of blocks N included in the NC command 2 and the maximum value of the block migration time in the block migration time storage unit 90. The maximum value of the block moving time is the maximum block moving time among the N block moving times calculated by the block moving time calculation unit 80.

Fig. 3 shows an example of the storage content 120 of the block transit time storage unit 90. The block moving time storage unit 90 includes a correspondence table between block IDs and block moving times. This table stores block moving times corresponding to the respective block IDs with all the block IDs included in the NC command 2 as keys. The block moving time storage unit 90 stores the total number of blocks and the maximum value of the block moving time.

As shown in fig. 4, the block travel time calculation unit 80 displays a button (machining time prediction button 132) for calculating the machining time of the NC program under editing on the edit screen of the NC program. Alternatively, the block travel time calculation unit 80 may assign a function for calculating the machining time of the NC program under editing to the soft key. When detecting that the button or soft key is selected, the block moving time calculation unit 80 calculates the total moving time and the block moving time for each block through the series of processes described above. The block moving time calculation unit 80 displays the calculated total moving time 134 at an arbitrary position on the NC program editing screen. In addition, the block moving time calculation unit 80 stores the block moving time for each block in the block moving time storage unit 90.

When the block moving time of each block is stored in the block moving time storage unit 90, the block moving time calculation unit 80 displays the block moving time 136 on the edit screen of the NC program. For example, as shown in fig. 4, the block moving time calculation unit 80 can display the block moving time of the block by a numerical value in the head of the block corresponding to each block ID. The display position of the numerical value is an example, and it does not matter at which position the numerical value is displayed as long as the correspondence between the block and the block movement time can be clearly visually recognized.

As shown in fig. 4, the block moving time calculation unit 80 may represent the block moving time of the block by changing the background color of the scroll bar 138 at the position corresponding to the block corresponding to each block ID. For example, the following procedure can express the block moving time 136 of each block by the background color of 10 stages.

(1) The block moving time calculation unit 80 divides the height of the entire scroll bar by the total number of blocks N to obtain the coordinates of the pixel row corresponding to the block.

(2) The block moving time calculation unit 80 divides the processing time into 10 ranges by dividing the maximum value yyyy of the block moving time by 10 (the number of display steps).

(3) The block moving time calculation unit 80 determines, for each block, in which range the block moving time is included. The display color is assigned to each range, and it is determined which display color corresponds to the block.

(4) The block moving time calculation unit 80 draws the pixel row corresponding to the block by the obtained display color.

The method of displaying the scroll bar 138 in different colors is an example, and the present invention is not limited thereto. The block moving time calculation unit 80 can display which part in the NC program takes how much time by the following method, for example.

(a) The block moving time calculation section 80 displays the block moving time (numerical value) at the head of the block line, the block itself (program text), or their background color, in a color without displaying the scroll bar 138 in a color-differentiated manner.

(b) The block moving time calculation section 80 displays the scroll bar 138 with different brightness, not with different colors.

(c) The block moving time calculation unit 80 displays a list in which the blocks are sorted in descending order of the block moving time. In the list, for example, the program block ID may be displayed as a list item, or a part of the program text may be displayed as a list item. When a list item is selected, an NC program editing screen that has migrated to the block is displayed.

(d) When the predicted machining time is equal to or less than the threshold value, the block moving time calculation unit 80 does not display the block moving time (numerical value) or the background color indicating the block moving time for the block. Alternatively, the block travel time calculation unit 80 does not display the block in the list of (c).

According to the present embodiment, the machining time prediction apparatus 1 calculates the predicted machining time (block moving time) for each block, and can display the block moving time 136 on the edit screen of the NC program. This makes it possible for the operator (worker) to intuitively recognize what part of the NC program takes, and therefore, visibility can be improved.

In addition, according to the present embodiment, the machining time prediction apparatus 1 directly associates a block with a block movement time, and displays the block movement time 136 by numerical values at the top of a line of an NC program, display colors such as a scroll bar, a list, and the like. Therefore, the operator can immediately find a part that takes a large amount of processing time in the NC program, and can quickly move to the part to edit the part. This can suppress the effort and time required for the correction work by searching for a location that takes processing time, and can reduce the burden on the operator (worker).

In addition, according to the present embodiment, "creation or correction of an NC program" and "checking a machining time of the NC program" can be performed on one screen. This prevents the operator from interrupting the operation flow and improves the operability.