JP2009265023A - Workpiece measuring device, collision avoidance device, and machine tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a workpiece measuring device, collision avoidance device, and machine tool can obtain easily three-dimensional data of workpiece configuration used to avoid collision caused by a workpiece and part of machine tools. <P>SOLUTION: The workpiece measuring device includes a measuring section 15 attached at a principal shaft tools to process the workpiece as a subject for manufacturing so as to contactlessly scan and measure the range of the workpiece and a configuration recognition section 23 where a three-dimensional mesh structure formed by dividing a space into polyhedron-like is created, a measuring point coordinate of the workpiece is computed based on range information on the workpiece measured, and when the ratio of the frequency of the computed measuring points is contained in one unit to frequency scanning the positions of workpiece corresponding to one unit of three-dimensional mesh structure is more than a predetermined threshold, and a measured configuration map is created by assuming one unit to be the configuration of the workpiece. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a workpiece measurement device, a collision prevention device, and a machine tool, and more particularly to a workpiece measurement device, a collision prevention device, and a machine tool that are suitable for use when performing three-dimensional machining on a workpiece.

  In general, when machining is performed by controlling a machine tool with a numerical controller (hereinafter referred to as “NC”), an NC program (NC data for machining) describing the movement of the tool of the machine tool is debugged. Yes. That is, a workpiece to be machined is set in advance on a table of a machine tool, and an operator runs the NC program step by step to verify the NC program.

  At this time, a part of a machine tool such as a tool or a ram may be damaged due to a human error such as an NC program failure or an erroneous operation by an operator (for example, patent document). 1).

  In particular, in a positioning operation of a tool that does not cut a workpiece, the operation speed is set to be high in order to increase work efficiency. When debugging the NC program in such a state, it is difficult to stop the spindle operation of the machine tool instantaneously at the operator's judgment when a part of the machine tool is likely to come into contact with the workpiece.

Various techniques have been proposed to prevent damage to the machine tool due to contact with the workpiece as described above.
For example, a sensor that detects contact between a workpiece and a tool is known, and the presence or absence of contact between the tool and the workpiece is confirmed using this sensor.

On the other hand, in order to avoid the collision between the workpiece and the tool, a control method for stopping the tool or the like before the collision with the workpiece is also known. When implementing this control method, it is necessary to grasp in advance the three-dimensional data (3D-CAD data) of the workpiece shape such as the workpiece size / dimension / shape and the position of the workpiece on the table.
However, the three-dimensional data of the workpiece shape before machining is often not grasped in advance, and it is necessary to grasp the workpiece by a method such as measuring the workpiece.

  As a method of grasping the three-dimensional data of the workpiece shape, a method of measuring without contact is known. For example, a digitizer that converts a three-dimensional object into digital data is known (see, for example, Non-Patent Document 1).

  A technique for measuring a fine surface shape such as a machining mark (cutting mark) using a non-contact displacement meter is also known (see, for example, Patent Documents 2 and 3). By attaching this displacement meter to the ram instead of the tool and scanning the workpiece, the shape of the workpiece can be detected with high accuracy.

As a method for expressing the three-dimensional data obtained in this way, a three-dimensional bitmap technique is known (see, for example, Patent Document 4).
Furthermore, as described above, a technique for automatically exchanging a workpiece detection device in the same manner as a tool is also known (see, for example, Patent Document 5).
JP 2007-048210 A JP 2004-012430 A JP 2004-012431 A International Publication No. 02/023408 Pamphlet Japanese Patent Laid-Open No. 4-089513 "Product enhancement of 3-D digitizer" Danae series "", 15th to 16th lines, [online], June 20, 2005, [March 7, 2008 search], Internet <URL: http://www.nec-eng.co.jp/press/050620press.html>

  The above-described method using a sensor that detects contact between a workpiece and a tool has a problem in that the operation speed of the tool or the like cannot be increased because of the contact, and the efficiency is poor. Furthermore, there has been a problem that contact with a workpiece cannot be detected depending on a portion in contact with the workpiece, such as when the ram contacts the workpiece.

  In the technique described in Non-Patent Document 1 described above, there is a problem that it is necessary to match the coordinate system when setting a workpiece, and it takes time and effort to measure. Furthermore, there is a problem that a region where the shape of the workpiece cannot be measured by the sensor, that is, a blind spot occurs. Another problem was the high price.

  In the techniques described in Patent Documents 2 and 3 described above, there is a problem that the obtained three-dimensional shape data is too detailed to be used for avoiding a collision between a workpiece and a tool. Since the sensor is scanned on all surfaces of the workpiece using the operation axis of the machine tool, there is a problem that the efficiency of acquiring the three-dimensional data is deteriorated. Since it is necessary to scan the sensor in accordance with the shape of the workpiece, there has been a problem that interference between the workpiece and a part of the machine tool, a sensor cable, or the like occurs when acquiring three-dimensional data.

  The present invention has been made to solve the above-described problem, and can easily acquire three-dimensional data of a workpiece shape used when preventing a workpiece and a part of a machine tool from colliding with each other. It aims at providing a measuring device, a collision prevention device, and a machine tool.

In order to achieve the above object, the present invention provides the following means.
The workpiece measuring device of the present invention is attached to a spindle to which a tool for machining a workpiece to be machined is attached, and measures a measurement unit that scans and measures the distance to the workpiece in a non-contact manner, and divides the space into a polyhedron shape. The three-dimensional mesh structure formed in this way is generated, the measurement point coordinates of the workpiece are calculated based on the measured distance information to the workpiece, and the position of the workpiece corresponding to one unit of the three-dimensional mesh structure When the ratio of the number of times the calculated measurement point is included in the unit to the number of times of scanning is equal to or greater than a predetermined threshold, the shape recognition unit creates a measurement shape map assuming that the unit is the shape of the workpiece And is provided.

According to the present invention, since the measurement shape map of the workpiece is created based on the ratio of the number of measurement points included in one unit with respect to the number of scans, the accuracy of the measurement shape map that is the three-dimensional data of the workpiece can be ensured. it can.
In other words, by creating a measurement shape map of a workpiece based on the ratio of the number of times a measurement point is included in one unit with respect to the number of scans, and creating a measurement shape map with distance information obtained by one scan and the like In comparison, the measurement accuracy of the measurement shape map is less likely to be affected by the measurement accuracy of the measurement unit and the distance from the measurement unit to the workpiece, and the accuracy of the measurement shape map is easily ensured.

  Furthermore, compared to methods such as exchanging with measurement units with different measurement accuracy, the accuracy of the measurement shape map is facilitated by adjusting the number of scans and threshold values that measure the distance to the workpiece that can be easily changed. Can be adjusted.

On the other hand, since the measurement unit is attached to the main shaft, it is easy to ensure the accuracy of the measurement shape map as compared with the case where the measurement unit is attached to other parts.
That is, since the measurement unit is attached to the spindle controlled with high positional accuracy because it is used for workpiece processing, the arrangement position of the measurement unit can be grasped with high accuracy. As a result, the arrangement position of the workpiece with respect to the machine tool including the spindle is grasped with high accuracy, and it is easy to ensure the position accuracy of the measurement shape map with respect to the machine tool.

  In other words, since the creation of a measurement shape map and the measurement of the arrangement position of the measurement shape map with respect to a machine tool or the like are performed at the same time, compared to a method using 3D design data of a workpiece as a measurement shape map, a machine tool, etc. Therefore, it is not necessary to separately perform the measurement of the arrangement position of the measurement shape map, that is, calibration, and the measurement shape map can be easily created.

Since a plurality of points where the measuring unit measures the distance to the workpiece can be set, it is possible to prevent the occurrence of a blind spot in the unmeasured area of the workpiece, that is, the workpiece as viewed from the measuring portion.
Since the measurement unit is attached to the spindle as described above, the accuracy of the measurement shape map is ensured even if a plurality of measurement points are set and the measurement unit is moved between the plurality of points. In addition, by measuring the distance from the measurement unit to the workpiece at a plurality of points, the occurrence of an unmeasured area in the workpiece can be prevented, and the entire workpiece can be measured.

  Furthermore, in order to measure the distance from the measuring unit attached to the spindle to the workpiece, for example, the distance from the measuring unit is measured at the same time, including a table on which the workpiece is placed and a fixing jig for fixing the workpiece to the table. . Therefore, a measurement shape map including a table and a fixing jig is created. The measurement shape map includes a table, a fixing jig, and the like as compared with the case where the three-dimensional design data of the workpiece is used as the measurement shape map. For example, the collision between the workpiece and a part of the machine tool is included. It becomes a measurement shape map suitable for prevention.

  In the above invention, the dimension of one side in the unit is set based on the distance between the tool and the spindle approaching the workpiece and shifting to machining of the workpiece, and the workpiece. It is desirable.

  According to the present invention, the dimension of one side in one unit of the three-dimensional mesh structure is set based on the distance between the workpiece and the point where the tool approaching the workpiece shifts to the machining of the workpiece, Contact between the workpiece and the tool during the period in which the spindle is moving at high speed is prevented.

That is, by controlling the movement of the tool and the spindle based on the measurement shape map, the interval between the machining transition point and the measurement shape map is ensured.
Furthermore, since the dimension of one side in one unit in the measurement shape map is set based on the distance between the above-described processing transition point and the workpiece, there is a gap less than the above-mentioned distance between the measurement shape map and the workpiece. Exists. Therefore, the distance between the actual machining transition point and the workpiece is the sum of the above-described interval and the above-described gap, and contact between the workpiece and the tool or the like during the period in which the tool and the spindle are moving at high speed is prevented.

  In the above invention, the measurement unit includes a sensor head that scans and measures the distance to the workpiece, a transmission unit that transmits distance information measured by the sensor head, and the sensor head and the transmission unit. A battery for supplying power, and a receiving unit for receiving the distance information transmitted from the transmitting unit and outputting the received distance information to the shape recognizing unit. Is desirable.

  According to the present invention, the measurement unit can measure the distance to the workpiece without using a wiring or the like for supplying power or transmitting distance information, and can output the measured distance information to the shape recognition unit. . That is, the sensor head measures the distance to the workpiece using the power supplied from the battery, and the transmission unit transmits the distance information obtained by the measurement to the shape recognition unit via the reception unit. There is no need to use wiring or the like for supplying or transmitting distance information.

For this reason, it is easy to attach and remove the measuring unit to / from the spindle, and the measuring unit can be replaced by an automatic exchange device such as an auto tool changer.
Furthermore, since the wiring etc. which connect between a measurement part and a shape recognition part are unnecessary, interference with wiring etc. and a workpiece | work can be prevented.

  In the above invention, it is preferable that the measurement unit is provided with an attachment unit that receives power supply through the main shaft and outputs the measurement information to the shape recognition unit through the main shaft.

According to the present invention, the measurement unit can measure the distance to the workpiece without using a wiring or the like for supplying power or transmitting distance information, and can output the measured distance information to the shape recognition unit. . In other words, the measuring unit receives power supplied through the main shaft and the mounting unit, measures the distance to the workpiece, and distance information obtained by the measurement is transmitted to the shape recognition unit through the main shaft and the mounting unit. In addition, it is not necessary to separately provide wiring for supplying power or transmitting distance information.
Therefore, since the wiring etc. which connect between a measurement part and a shape recognition part are unnecessary, interference with wiring etc. and a workpiece | work can be prevented.

  The collision preventing apparatus of the present invention is based on the workpiece measuring apparatus of the present invention, a determination unit that determines at least interference between the spindle or the tool and the measurement shape map, and a determination result of the determination unit. And a control unit for controlling the movement of the spindle.

According to the present invention, it is possible to prevent at least a collision between the spindle or the tool and the workpiece based on the measurement shape map created by the workpiece measuring device of the present invention.
In other words, by determining the interference between the measurement shape map larger than the workpiece and the spindle or the like, the collision between the workpiece smaller than the measurement shape map and the spindle or the like is surely prevented.

  The machine tool according to the present invention is provided with a table on which a workpiece to be machined is installed, a spindle to which a tool for machining the workpiece is attached, and the collision preventing apparatus according to the present invention.

According to the present invention, it is possible to prevent a collision between at least the spindle or the tool and the workpiece, the table, or the like based on the measurement shape map created by the workpiece measuring device of the present invention.
In other words, by judging the interference between the measurement shape map larger than the workpiece and the table and the spindle and the like, the collision between the workpiece and table etc. smaller than the measurement shape map and the spindle and the like is surely prevented.

  According to the workpiece measuring device, the collision preventing device, and the machine tool of the present invention, since the measurement shape map of the workpiece is created based on the ratio of the number of measurement points included in one unit with respect to the number of scans, There is an effect that it is possible to easily acquire the three-dimensional data of the workpiece shape used when preventing the collision with the part.

[First Embodiment]
Hereinafter, a machine tool according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 5.
FIG. 1 is a schematic diagram illustrating the overall configuration of the machine tool according to the present embodiment. FIG. 2 is a block diagram illustrating a control unit in the machine tool of FIG.

The machine tool 1 according to the present embodiment includes a workpiece measuring device 2 that creates a measurement shape map MP based on a workpiece W and the like, and a collision prevention that prevents a collision between the ram 13 or the tool of the machine tool 1 and the workpiece W or the like. A five-face processing machine that includes the device 3 and that processes a workpiece W to be processed from five directions, the operation of which is controlled by the NC.
As shown in FIGS. 1 and 2, the machine tool 1 includes a table 11 that moves in the X-axis direction, a saddle 12 that moves in the Y-axis direction, a ram (main shaft) 13 that moves in the Z-axis direction, a ram 13, a measuring unit 15 that measures the distance to the workpiece W, and a machine tool control unit 16 that performs NC control of the movement of the table 11, the saddle 12, and the ram 13 are provided.

  The table 11 is a table to which the workpiece W is fixed, and is arranged so as to be movable along the X-axis direction as shown in FIG. As shown in FIG. 2, the movement of the table 11 in the X-axis direction is controlled by the movement control unit 26 of the machine tool control unit 16.

  As shown in FIG. 1, the saddle 12 is provided with a beam portion 14 </ b> A in which a ram 13 is arranged and extends in the Y-axis direction of a support portion 14 that is formed in a gate shape and is disposed across the table 11. It is arranged and can be moved along the Y-axis direction. As shown in FIG. 2, the movement of the saddle 12 in the Y-axis direction is controlled by the movement control unit 26.

  As shown in FIG. 1, the ram 13 has a measuring unit 15 attached to the end on the table 11 side when measuring the shape of the workpiece W, and a tool attached when cutting the workpiece W. Further, the ram 13 is disposed on the saddle 12 and is movable along the Z-axis direction. As shown in FIG. 2, the movement of the ram 13 in the Z-axis direction is controlled by the movement control unit 26.

FIG. 3 is a partially enlarged view illustrating the configuration of the measurement unit and the ram in FIG.
The measurement unit 15 is a laser distance sensor used when creating the measurement shape map MP of the workpiece W, and is attached to the end of the ram 13 on the table 11 side as shown in FIGS. It is.
As shown in FIG. 3, the measurement unit 15 performs two-dimensional scanning (scanning) by changing the emission angle θ of the laser beam used for distance measurement. Further, by rotating the ram 13 around the central axis L, the measurement unit 15 performs a three-dimensional scan.
The distance information from the workpiece W, the table 11 and the like measured by the measurement unit 15 to the measurement unit 15 is input to the shape recognition unit 23 as shown in FIG.

  The machine tool control unit 16 creates a measurement shape map MP of the workpiece W before cutting the workpiece W, and based on the created measurement shape map MP when debugging the NC program describing the movement of the tool for cutting the workpiece W Thus, the collision between the ram 13 and the tool and the workpiece W is prevented, and the movement of the table 11, the saddle 12 and the ram 13 is controlled when the workpiece W is cut.

  As shown in FIG. 2, the machine tool control unit 16 includes a program storage unit 21 and a program interpretation unit 22 that generate a signal for controlling the movement of the tool when machining the workpiece W, and a measurement shape map of the workpiece W. Controls the movement of the shape recognition unit 23 that creates the MP, the shape storage unit 24 that stores the shape of the tool attached to the spindle, the interference determination unit (determination unit) 25, the table 11, the saddle 12, and the ram 13. A movement control unit (control unit) 26 is provided.

  Here, the workpiece measuring device 2 includes a measuring unit 15 and a shape recognizing unit 23, and the collision prevention device 3 includes a workpiece measuring device 2, an interference determining unit 25, and a movement control unit 26.

The program storage unit 21 stores an NC program describing a moving path of a tool for cutting the workpiece W.
As shown in FIG. 2, the program storage unit 21 is connected to the program interpretation unit 22, and the NC program stored in the program storage unit 21 is output to the program interpretation unit 22.

The program interpretation unit 22 creates information related to the moving amount and moving speed of the tool based on the NC program.
As shown in FIG. 2, the program interpretation unit 22 is connected to the interference determination unit 25 and the movement control unit 26, and information on the amount of movement of the tool and the like created by the program interpretation unit 22 is the interference determination unit 25 and the movement control. Is output to the unit 26.

The shape recognizing unit 23 creates a measurement shape map MP used for preventing the collision between the ram 13, the tool, and the work W when debugging the NC program.
As shown in FIG. 2, the shape recognition unit 23 is connected to the measurement unit 15 and the interference determination unit 25. The distance information measured by the measuring unit 15 is input to the shape recognizing unit 23, and the information of the measured shape map MP is output from the shape recognizing unit 23 to the interference determining unit 25.
A method for creating the measurement shape map MP in the shape recognition unit 23 will be described later.

The shape storage unit 24 stores the ram 13 that may collide when approaching the workpiece W, the shape of a tool attached to the ram 13, and the like.
As shown in FIG. 2, the shape storage unit 24 is connected to the interference determination unit 25. The shape of the ram 13 or the like stored in the shape storage unit 24 is output to the interference determination unit 25.

The interference determination unit 25 prevents collision between the ram 13 or the tool and the workpiece W by determining interference between the measurement shape map MP and the ram 13 or the like when debugging the NC program.
As shown in FIG. 2, the interference determination unit 25 is connected to a shape recognition unit 23, a shape storage unit 24, a program interpretation unit 22, and a movement control unit 26. The interference determination unit 25 receives the measurement shape map MP from the shape recognition unit 23, the shape such as the ram 13 from the shape storage unit 24, and the information related to the amount of movement of the tool and the like from the program interpretation unit 22. ing. On the other hand, the determination result of the presence or absence of interference in the interference determination unit 25 is output to the movement control unit 26.

The movement control unit 26 controls the movement amount and movement speed of a tool or the like attached to the end of the ram 13 by controlling the movement of the table 11, the saddle 12 and the ram 13. Further, when it is determined that the measurement shape map MP interferes with the ram 13 or the like during NC program debugging, the movement of the table 11, the saddle 12 and the ram 13 is stopped.
As shown in FIG. 2, the movement control unit 26 is connected to the program interpretation unit 22 and the interference determination unit 25. Information such as the amount of movement of the tool or the like is input from the program interpretation unit 22 to the movement control unit 26, and a determination result of the presence or absence of interference between the measurement shape map MP and the ram 13 is input from the interference determination unit 25. . On the other hand, control signals for controlling the movement of the table 11, the saddle 12 and the ram 13 created in the movement control unit 26 are output to the table 11, the saddle 12 and the ram 13, respectively.

Next, the processing method of the workpiece | work W in the machine tool 1 which consists of said structure is demonstrated.
When processing the workpiece W by the machine tool 1, first, the workpiece W is fixed on the table 11 using the fixing jig J (see FIG. 5).
Thereafter, as shown in FIG. 2, the NC program is output from the program storage unit 21 to the program interpretation unit 22 in units of one block (one movement unit, for example, one line segment).

  The program interpretation unit 22 creates information related to the movement amount and movement speed of the tool or the like from the NC program and outputs the information to the movement control unit 26. The movement control unit 26 decomposes the input information into the movement amounts and movement speeds of the table 11, the saddle 12 and the ram 13, and sends control signals for controlling the movement amounts and movement speeds of the table 11, the saddle 12 and the ram 13, respectively. Output.

  The table 11, the saddle 12 and the ram 13 to which the control signal is input from the movement control unit 26 are driven based on the control signal input by the motor provided therein, and the workpiece W is processed.

Next, a method of creating the measurement shape map MP of the workpiece W, which is a feature of the present embodiment, and a method of preventing a collision between the workpiece W using the created measurement shape map MP and a part of the machine tool 1 explain.
The creation of the measurement shape map MP of the workpiece W and the collision prevention control described here are, for example, the debugging of the NC program in the previous stage of machining the workpiece W, that is, the workpiece W and the ram 13 or tool. This is done when checking for interference.

FIG. 4 is a flowchart illustrating a method for creating a measurement shape map. FIG. 5 is a schematic diagram for explaining the distance measurement from the measurement unit to the workpiece.
First, as shown in FIG. 5, the workpiece W is set on the table 11 (step S1). At this time, the workpiece W is fixed to the table 11 by the fixing jig J.

  Thereafter, as shown in FIG. 3, the measurement unit 15 is attached to the end of the ram 13 (step S2). The measurement unit 15 and the shape recognition unit 23 of the machine tool control unit 16 can supply power to the measurement unit 15 and input distance information measured by the measurement unit 15 to the shape recognition unit 23 using, for example, a cable. Connected (see FIG. 2).

When the measurement unit 15 is attached to the ram 13, as shown in FIG. 5, the measurement unit 15 moves to the first measurement position P1, and the distance from the measurement unit 15 to the workpiece W is measured (step S3).
As shown in FIG. 3, the measurement unit 15 emits laser light while changing the scan angle θ, and measures the distance r from the measurement unit 15 to the workpiece W. In other words, a two-dimensional scan is performed. At the same time, the distance from the measurement unit 15 to the table 11 and the distance from the measurement unit 15 to the fixing jig J are also measured. Further, the ram 13 is rotated around the central axis L, and the two-dimensional scanning is performed again by changing the scanning direction of the laser beam by the measuring unit 15. Thereby, a three-dimensional scan of the workpiece W is performed.

  When the three-dimensional scan at the first measurement position P1 is completed, the measurement unit 15 is then moved to the second measurement position P2, and the workpiece W is again three-dimensionally scanned. The second measurement position P2 is a position at which a blind spot BA generated when the measuring unit 15 performs a three-dimensional scan of the workpiece W from the first measurement position P1, in other words, a non-measurement area can be measured.

  As these measurement positions, for example, five locations above the workpiece W (Z-axis positive direction), front (X-axis positive direction), rear (X-axis negative direction), and both sides (Y-axis positive direction and negative direction). Can be mentioned. Note that the number and location of measurement positions are not particularly limited because they vary depending on the arrangement position and shape of the workpiece W, the reflectance of the laser light emitted from the measurement unit 15, and the like.

The distance r and the scan angle θ measured by the measurement unit 15 are input to the shape recognition unit 23 as shown in FIG. Further, the position (Xr, Yr, Zr) of the ram 13 at the time when the distance r is measured and the rotation angle φ of the ram 13 are also input to the shape recognition unit 23.
Based on the input information, the shape recognition unit 23 calculates the coordinates (Xm, Ym, Zm) of the measurement point of the workpiece W at which the distance r is measured based on the following calculation formula (step S4).
Xm = Xr + r · sin θ
Ym = Yr + r · sinφ
Zm = Zr-r · cosφ · cosθ

FIG. 6 is a diagram for explaining the shape of the measurement shape map defined by the shape recognition unit.
The shape recognition unit 23 divides the measurement space into hexahedral three-dimensional mesh regions, that is, generates a three-dimensional mesh structure, and the three-dimensional mesh structure including the coordinates (Xm, Ym, Zm) of the measurement points described above. Vote for one unit (hereinafter referred to as “voxel”) and define the measurement shape map MP (step S5).

Specifically, each time a two-dimensional scan is performed by the measurement unit 15, a vote, for example, “1” is registered in the voxel including the coordinates of the measurement point. This process is performed for all secondary scans.
As a result, each voxel is voted as many times as the number of two-dimensional scans is performed, and when it is the smallest, it is not voted once.

  The shape recognition unit 23 determines whether or not the work W is included in each voxel according to the number of votes for the total number of secondary scans. That is, when the ratio of the number of votes to the total number of secondary scans is higher than a predetermined threshold, the work W is included in the voxel, and when the ratio is lower than the predetermined threshold, the work is included in the voxel. It is determined that W is not included.

  Note that the predetermined threshold value varies depending on the measurement accuracy of the measurement unit 15, the reflectance of the workpiece W, and the like, and is not particularly limited.

On the other hand, the dimension of one side of the above-described voxel is such as a tool or a ram 13 when switching from the approach mode in which the tool approaches the workpiece W to the machining mode in which the workpiece W is cut by the tool when the machine tool 1 is machined. It is set based on the distance between the part of the machine 1 and the workpiece W.
This distance is set in consideration of items such as the performance and application of the machine tool 1, workpiece specifications, operator workability, and measurement processing speed. For this reason, the dimension of one side of the voxel can be exemplified by a value of about 1 mm to about 40 mm, but is not particularly limited because it is a value that varies depending on the above items.

When the measurement shape map MP is created by the shape recognition unit 23, the NC program is debugged.
First, a tool such as an end mill used for machining the workpiece W is attached to the end of the ram 13.

  Then, as shown in FIG. 2, the NC program is output from the program storage unit 21 to the program interpretation unit 22 block by block according to an operator's instruction, and information from the program interpretation unit 22 on the amount of movement of the tool etc. 25 is output.

The interference determination unit 25 is based on the input information on the movement amount of the tool, the measurement shape map MP input from the shape recognition unit 23, and the tool and the shape of the ram 13 input from the shape storage unit 24. The presence or absence of interference is determined.
The shape of the tool and the ram 13 input to the interference determination unit 25 is stored in the shape storage unit 24 in advance, and the tool and the ram 13 attached to the machine tool 1 when performing a debugging operation or the like. Shape.

  The interference determination unit 25 determines whether the tool or the ram 13 interferes with the measurement shape map MP when the tool and the ram 13 are moved based on the information on the movement amount of the tool or the like, and the determination result is determined. Output to the movement control unit 26.

  When the interference determination unit 25 determines that interference occurs, the movement control unit 26 stops the execution of the NC program in which interference occurs, and the collision between the tool or ram 13 and the workpiece W is prevented.

  On the other hand, when it is determined by the interference determination unit 25 that no interference occurs, the movement control unit 26 controls the table 11, the saddle 12 and the ram 13 based on the input information on the movement amount of the tool and the like. Is output.

  According to the above configuration, since the measurement shape map MP of the workpiece W is created based on the ratio of the number of times the measurement point is included in the voxel with respect to the number of two-dimensional scans, the measurement shape map MP that is the three-dimensional data of the workpiece W Accuracy can be ensured. Therefore, the three-dimensional data of the workpiece W shape used when preventing the workpiece W from colliding with the ram 13 or the like of the machine tool 1 can be easily acquired.

  In other words, by creating the measurement shape map MP of the workpiece W based on the ratio of the number of times the measurement point is included in the voxel with respect to the number of two-dimensional scans, the measurement shape map MP is obtained using distance information obtained by one scan. Compared with the case of creating, it is less affected by the measurement accuracy of the measurement unit 15 and the distance r from the measurement unit 15 to the workpiece W, and the accuracy of the measurement shape map MP can be ensured.

  Furthermore, the accuracy of the measurement shape map MP can be easily adjusted by adjusting the number of two-dimensional scans, threshold values, and the like that can be easily changed, compared to a method of replacing the measurement unit 15 with a different measurement accuracy. .

On the other hand, since the measurement unit 15 is attached to the ram 13, the accuracy of the measurement shape map MP can be easily ensured as compared with the case where the measurement unit 15 is attached to other parts.
That is, since the measurement unit 15 is attached to the ram 13 that is controlled with high positional accuracy because it is used for machining the workpiece W, the arrangement position of the measurement unit 15 is grasped with high accuracy. As a result, the arrangement position of the workpiece W with respect to the machine tool 1 including the ram 13 is also grasped with high accuracy, and the position accuracy of the measurement shape map MP with respect to the machine tool 1 can be easily ensured.

  In other words, in order to simultaneously perform the creation of the measurement shape map MP and the measurement of the arrangement position of the measurement shape map MP with respect to the machine tool 1, it is compared with the method of using the three-dimensional design data of the workpiece W as the measurement shape map MP. Therefore, there is no need to separately measure the arrangement position of the measurement shape map MP with respect to the machine tool 1, that is, calibration, and the measurement shape map MP can be easily created.

By setting a plurality of points where the measuring unit 15 measures the distance r to the workpiece W, it is possible to prevent the occurrence of a blind spot BA in the unmeasured area in the workpiece W, that is, the workpiece W viewed from the measuring unit.
Since the measurement unit 15 is attached to the ram 13, the accuracy of the measurement shape map MP is ensured even if a plurality of measurement points are set and the measurement unit 15 is moved between the plurality of points. In addition, by measuring the distance r from the measurement unit 15 to the workpiece W at a plurality of points P1 and P2, the occurrence of a blind spot BA in the workpiece W is prevented, and the entire workpiece W can be measured.

  Further, in order to measure the distance r from the measurement unit 15 attached to the ram 13 to the workpiece W, including the table 11 on which the workpiece W is mounted and the fixing jig J that fixes the workpiece W to the table, the measurement unit 15 includes Are measured simultaneously. Therefore, a measurement shape map MP including the table 11 and the fixing jig J is created. The measurement shape map MP includes the table 11 and the fixing jig J as compared with the case where the three-dimensional design data of the workpiece W is used as the measurement shape map MP. The measurement shape map MP is suitable for preventing the collision with the ram 13 and the like.

  Since the dimension of one side in the voxel is set based on the distance between the point where the tool approaching the workpiece W shifts to the machining of the workpiece W and the workpiece W, the tool and the ram 13 are moving at high speed. The contact between the workpiece W and the tool or the like during the period can be prevented.

That is, by controlling the movement of the tool and the ram 13 based on the measurement shape map MP, the interval between the machining transition point and the measurement shape map MP is ensured.
Furthermore, since the dimension of one side in the voxel of the measurement shape map MP is set based on the distance between the processing transition point and the workpiece W, the distance between the measurement shape map MP and the workpiece W is set as described above. There are less than gaps. Therefore, the distance between the actual processing transition point and the workpiece W is the sum of the above-described interval and the above-described gap, and the contact between the workpiece W and the tool or the like during the period in which the tool and the ram 13 are moving at high speed can be prevented. .

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIGS.
The basic configuration of the machine tool of this embodiment is the same as that of the first embodiment, but the configuration of the measurement unit and the machine tool control unit is different from that of the first embodiment. Therefore, in this embodiment, only the periphery of the measurement unit and the machine tool control unit will be described with reference to FIGS. 7 to 9, and the description of the same components and the like will be omitted.
FIG. 7 is an overall view illustrating the configuration of the machine tool of the present embodiment. FIG. 8 is a block diagram illustrating the configuration of the measurement unit in FIG.
In addition, the same code | symbol is attached | subjected to the component same as 1st Embodiment, and the description is abbreviate | omitted.

  As shown in FIGS. 7 and 8, the machine tool 101 is attached to a table 11 that moves in the X-axis direction, a saddle 12 that moves in the Y-axis direction, a ram 13 that moves in the Z-axis direction, and a ram 13. A measuring unit 115 that measures the distance to the workpiece W and a machine tool control unit 116 that performs NC control of the movement of the table 11, the saddle 12 and the ram 13 are provided.

The measurement unit 115 is a laser distance sensor used when creating the measurement shape map MP of the workpiece W, and is attached to the end of the ram 13 on the table 11 side as shown in FIG.
Further, the measuring unit 115 is attached to and detached from the end of the ram 13 by an auto tool changer of the machine tool 101, like a tool for machining the workpiece W.
As shown in FIG. 8, the measurement unit 115 is provided with a sensor head 121, a sensor control unit 122, a transmission unit 123, and a battery 124.

The sensor head 121 performs two-dimensional scanning (scanning) by changing the emission angle θ of the laser beam used for distance measurement.
As shown in FIG. 8, the sensor head 121 is connected to the sensor control unit 122 and the battery 124. A control signal is input to the sensor head 121 from the sensor control unit 122 and power is supplied from the battery 124. On the other hand, the distance information measured by the sensor head 121 is output to the sensor control unit 122.

The sensor control unit 122 controls the emission of the laser light from the sensor head 121 and the scan angle θ.
As shown in FIG. 8, the sensor control unit 122 is connected to the sensor head 121, the transmission unit 123, and the battery 124. Distance information measured from the sensor head 121 is input to the sensor control unit 122, and power is supplied from the battery 124. On the other hand, a control signal is output from the sensor control unit 122 to the sensor head 121, and distance information is output to the transmission unit 123.

The transmission unit 123 wirelessly transmits the distance information measured by the sensor head 121 to the reception unit 131 of the machine tool control unit 116.
As shown in FIG. 8, the transmission unit 123 is connected to the sensor control unit 122 and the battery 124. The transmission unit 123 receives distance information from the sensor control unit 122 and is supplied with power from the battery 124. The distance information input to the transmission unit 123 is transmitted to the reception unit 131 by radio.

  The battery 124 supplies power to the sensor head 121, the sensor control unit 122, and the transmission unit 123. As shown in FIG. 8, the battery 124 is connected to the sensor head 121, the sensor control unit 122, and the transmission unit 123 so that power can be supplied.

  The machine tool control unit 116 creates a measurement shape map MP of the workpiece W before cutting the workpiece W, and based on the created measurement shape map MP when debugging the NC program describing the movement of the tool for cutting the workpiece W Thus, the collision between the ram 13 and the tool and the workpiece W is prevented, and the movement of the table 11, the saddle 12 and the ram 13 is controlled when the workpiece W is cut.

FIG. 9 is a block diagram illustrating the configuration of the machine tool control unit of FIG.
As shown in FIG. 9, the machine tool control unit 16 includes a receiving unit 131 that receives distance information transmitted from the measuring unit 115, a program storage unit 21 and a program interpreting unit 22, a shape recognition unit 23, and a shape A storage unit 24, an interference determination unit 25, and a movement control unit 26 are provided.

The reception unit 131 receives distance information wirelessly transmitted from the transmission unit 123 of the measurement unit 115.
As shown in FIG. 9, the reception unit 131 is connected to the shape recognition unit 23, and outputs the received distance information to the shape recognition unit 23.

Next, operations of the transmission unit 123 and the machine tool control unit 116, which are features of the present embodiment, will be described.
The measuring unit 115 according to the present embodiment is automatically attached to and detached from the ram 13 by an auto tool changer in the same manner as a tool for processing the workpiece W.

  When measuring the distance from the measurement unit 115 to the workpiece W, a control signal is output from the sensor control unit 122 to the sensor head 121, and a measurement laser is output from the sensor head 121. The distance information measured by the sensor head 121 is output from the sensor head 121 to the sensor control unit 122 and is output from the sensor control unit 122 to the transmission unit 123.

As shown in FIGS. 8 and 9, the transmission unit 123 wirelessly transmits the input distance information to the machine tool control unit 116. The distance information transmitted wirelessly is received by the reception unit 131 and is output from the reception unit 131 to the shape recognition unit 23.
Since the subsequent operation is the same as that of the first embodiment, the description thereof is omitted.

  According to the above configuration, the measurement unit 115 measures the distance to the workpiece W without using a wiring for supplying power or transmitting distance information, and outputs the measured distance information to the shape recognition unit 23. can do. That is, the sensor head 121 measures the distance to the workpiece W using the power supplied from the battery 124, and the transmission unit 123 transmits the distance information obtained by the measurement to the shape recognition unit via the reception unit 131. Therefore, it is not necessary to use wiring for supplying power or transmitting distance information.

Therefore, it becomes easy to attach and remove the measuring unit 115 to and from the ram 13, and the measuring unit 115 can be exchanged by an automatic exchange device such as an auto tool changer.
Furthermore, since the wiring etc. which connect between the measurement part 115 and the shape recognition part 23 are unnecessary, interference with wiring etc. and the workpiece | work W can be prevented.

[Third Embodiment]
Next, a third embodiment of the present invention will be described with reference to FIG.
The basic configuration of the processing machine of this embodiment is the same as that of the first embodiment, but differs from the first embodiment in the ram, the measurement unit, and the attachment method. Therefore, in the present embodiment, only the periphery of the ram and the measurement unit will be described using FIG. 10, and the description of the same components and the like will be omitted.
FIG. 10 is an overall view illustrating the configuration of the machine tool of the present embodiment.
In addition, the same code | symbol is attached | subjected to the component same as 1st Embodiment, and the description is abbreviate | omitted.

As shown in FIG. 10, the machine tool 201 includes a table 11 that moves in the X-axis direction, a saddle 12 that moves in the Y-axis direction, a ram 13 that moves in the Z-axis direction, and a measurement unit attached to the ram 13. 215 are provided.
The measurement unit 215 is provided with a measurement unit 15 that measures the distance to the workpiece W and an attachment unit 216 that is attached to the ram 13.

The attachment portion 215 is an attachment provided with the measurement portion 15 and configured to be detachable from the ram 13.
The mounting portion 216 is provided with an interface (not shown) through which electric power is supplied to the ram 13 and signals such as control signals and distance information are transmitted.

  In the present embodiment, the description is applied to the mounting portion 215 configured to extend from the end portion of the ram 13 in the Z-axis direction and support the measuring unit 13 in the direction in which the central axis extends along the Z-axis, but is limited to this configuration. Without limitation, for example, a configuration in which the measurement unit 13 is supported so that the central axis is parallel to the XY plane, or a configuration in which the direction of the central axis of the measurement unit 13 can be arbitrarily controlled may be used. It is not a thing.

Similar to the first and second embodiments, the measurement unit 215 is attached to the ram 13 when debugging an NC program or the like.
The attaching operation is automatically performed in the same manner as the attachment for processing, using an exchange device (not shown) used for replacing the attachment used for processing the workpiece W. When the measuring unit 215 is not used, such as when processing the workpiece W, it is stored in an automatic replacement storage box (not shown) provided in the machine tool 201, similarly to the processing attachment.

According to the above configuration, the measurement unit 15 measures the distance to the workpiece W without using a wiring for supplying power, transmitting distance information, and the like, and outputs the measured distance information to the shape recognition unit 23. can do. In other words, the measurement unit 15 receives the supply of power through the ram 13 and the mounting unit 215 and measures the distance to the workpiece W, and the distance information obtained by the measurement is recognized by the shape through the ram 13 and the mounting unit 215. Since it is transmitted to the unit 23, it is not necessary to separately provide wiring or the like for supplying power or transmitting distance information.
Therefore, since the wiring etc. which connect between the measurement part 15 and the shape recognition part 23 are unnecessary, interference with wiring etc. and the workpiece | work W can be prevented.

It is a mimetic diagram explaining the whole machine tool composition concerning a 1st embodiment of the present invention. It is a block diagram explaining the control part in the machine tool of FIG. It is the elements on larger scale explaining the structure of the measurement part of FIG. 1, and a ram. It is a flowchart explaining the production method of a measurement shape map. It is a schematic diagram explaining the distance measurement from a measurement part to a workpiece | work. It is a figure explaining the shape of the measurement shape map defined by the shape recognition part. It is a whole view explaining the structure of the machine tool of the 2nd Embodiment of this invention. It is a block diagram explaining the structure of the measurement part of FIG. It is a block diagram explaining the structure of the machine tool control part of FIG. It is a whole view explaining the structure of the machine tool of the 3rd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,101 Machine tool 2,102 Work measuring device 3,103 Collision prevention device 13 Ram (spindle)
15, 115 Measurement unit 23 Shape recognition unit 25 Interference determination unit (determination unit)
26 Movement control unit (control unit)
121 Sensor head 123 Transmitter 124 Battery 216 Mounting part W Work MP Measurement shape map

Claims (6)

A measuring unit that is attached to a spindle to which a tool for processing a workpiece to be processed is attached and that measures by scanning a distance to the workpiece in a non-contact manner;
Generate a three-dimensional mesh structure formed by dividing the space into polyhedrons,
Based on the measured distance information to the workpiece, to calculate the measurement point coordinates of the workpiece,
When the ratio of the number of times the calculated measurement point is included in the unit to the number of times the position of the workpiece corresponding to the unit of the three-dimensional mesh structure is scanned is equal to or greater than a predetermined threshold, the unit is A shape recognition unit that creates a measurement shape map as the shape of the workpiece;
Is provided with a workpiece measuring device.   The dimension of one side in the unit is set based on a distance between the tool and the spindle approaching the workpiece and shifting to machining of the workpiece, and the workpiece. The workpiece measuring apparatus according to claim 1. The measurement unit includes a sensor head that scans and measures the distance to the workpiece, a transmission unit that transmits distance information measured by the sensor head, and a battery that supplies power to the sensor head and the transmission unit And provided,
Furthermore, the receiving part which receives the said distance information transmitted from the said transmission part, and outputs the said distance information received to the said shape recognition part is provided. Workpiece measuring device.   2. The measuring unit is provided with an attachment unit that receives power supply through the main shaft and outputs the measurement information to the shape recognition unit through the main shaft. 2. The workpiece measuring apparatus according to 2. The workpiece measuring device according to claim 1, and
A determination unit that determines at least interference between the spindle or the tool and the measurement shape map;
A control unit for controlling movement of the spindle based on a determination result of the determination unit;
An anti-collision device characterized by that. A table on which a workpiece to be machined is placed;
A spindle to which a tool for machining the workpiece is attached;
A collision preventing device according to claim 5;
A machine tool characterized in that is provided.

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