JP2023067510A - Controller, processing route generation method, and computer program - Google Patents

Abstract

To provide a machine tool making it possible to diminish correction work to be performed by an operator for the purpose of generating a highly precise processing route.SOLUTION: A machine tool performs an approach motion of causing a main shaft to approach the perimeter of a master workpiece along a reference route on an external or internal circumference of the master workpiece determined based on plural reference points, and determines whether a tool comes into contact with the perimeter during the approach motion. When the tool comes into contact with the perimeter, the machine tool acquires the coordinates of the main shaft, performs a receding motion of causing the main shaft to recede from the reference route in a receding angle direction or a direction of a predetermined angle, performs the approach motion and receding motion, acquires the coordinates of the main shaft every time the tool comes into contact with the perimeter during the approach motion, generates a processing route of the main shaft on the basis of plural sets of coordinates, computes a reference angle that is an angle defined with the coordinates of the main shaft and the coordinates of the reference point, determines whether the receding angle is larger or smaller than a border angle that is 180 degrees or an angle based on the reference angle, corrects the receding angle on the basis of a result of the determination and a predetermined angle, and then performs the receding motion using the corrected receding angle.SELECTED DRAWING: Figure 9

Description

The present technology relates to a control device, a machining path generation method, and a computer program that generate a machining path for a spindle on which a tool is mounted.

When removing burrs formed on the surface of a work, for example, the outer circumference of the work or the inner circumference of a hole in the work, the tool is mounted on the spindle of the machine tool, and the spindle moves along the outer circumference or inner circumference of the work, removing burrs. remove. The machine tool generates a machining path before moving the spindle. The spindle moves along the machining path.

The machining path of the spindle can be generated by off-line teaching. Off-line teaching can automatically generate a spindle machining path for avoiding interference between the workpiece and the spindle based on the CAD data of the workpiece (see Patent Document 1, for example).

JP 2019-150864 A

However, the machining path is a rough path, and after the machining path is generated, the operator needs to correct the machining path while checking the operation of the spindle in order to create a highly accurate machining path.

The present disclosure has been made in view of such circumstances, and aims to provide a control device, a machining path generation method, and a computer program that can reduce operator's correction work for generating a highly accurate machining path. and

A control device according to an embodiment of the present disclosure is a spindle for mounting a tool on the peripheral edge of the masterwork along a reference path on the outer peripheral side or the inner peripheral side of the masterwork determined based on a plurality of reference points. A first moving unit that performs an approaching operation, a contact determination unit that determines whether or not the tool has come into contact with the peripheral edge portion during the approaching operation by the first moving unit, and a case where the contact determination unit determines that the tool has come into contact. an acquisition unit that acquires the coordinates of the main axis; and a second moving unit that, after the acquisition unit acquires the coordinates of the main axis, separates the main axis in a separation angle direction that is a predetermined angle with respect to the reference path. and performing an approaching operation by the first moving part and a separating operation by the second moving part, acquiring the coordinates of the main axis each time the tool contacts the peripheral edge part during the approaching operation, and acquiring the acquired plural In a numerical control device that generates a machining path of the spindle based on the coordinates of the reference angle calculation unit that calculates a reference angle that is an angle formed by the coordinates of the spindle acquired by the acquisition unit and the coordinates of the reference point a magnitude determination unit for determining the magnitude of the separation angle and a boundary angle that is 180 degrees or an angle based on the reference angle calculated by the reference angle calculation unit; and the separation angle based on the determination result of the magnitude determination unit. and a correction unit that corrects the separation angle based on a predetermined angle, and the second moving unit performs a separation operation using the separation angle corrected by the correction unit.

In the present disclosure, the spindle moves toward and away from the peripheral edge of the masterwork along the reference path. When the tool touches the periphery during the approaching motion, the control device acquires the coordinates of the spindle and generates a machining path based on the coordinates. Also, a reference angle formed by the current coordinates of the main axis and the coordinates of the reference point is calculated, and the magnitude of the separation angle, which is the direction of the separation operation, and 180 degrees or the boundary angle, which is the angle based on the reference angle, is determined. Correct the separation angle based on the results. If the separation angle needs to be corrected, i.e., if there is a possibility of contact with the master work, the separation angle is corrected. It can reduce the correction work of the operator.

In the control device according to an embodiment of the present disclosure, the reference angle calculation unit may combine the first coordinates of the main axis acquired by the acquisition unit and the An angle formed by the second coordinate of the main axis and the reference point acquired by the acquisition unit is calculated.

In the present disclosure, an appropriate reference angle is calculated based on the first coordinate, the second coordinate, and the reference point.

In the control device according to an embodiment of the present disclosure, the magnitude determination unit includes a first calculation unit that calculates a first comparison angle based on 180 degrees, and a reference angle calculated by the reference angle calculation unit that a first angle determination unit that determines whether or not the reference angle is smaller than the one comparison angle, and the correction unit, when the first angle determination unit determines that the reference angle is smaller than the first comparison angle , the first correction is performed by adding the correction amount to the separation angle.

In the present disclosure, since the magnitude of the first comparison angle based on the reference angle and 180 degrees is determined, it is possible to prevent contact with the masterwork.

In a control device according to an embodiment of the present disclosure, the magnitude determination unit includes a second calculation unit that calculates a second comparison angle based on the separation angle, and a reference angle that is calculated by the reference angle calculation unit. a second angle determination unit that determines whether or not the reference angle is smaller than the second comparison angle, and the correction unit corrects the separation angle when determining that the reference angle is smaller than the second comparison angle. A second correction is made by adding the amount.

In the present disclosure, when the reference angle is smaller than the second comparison angle, correction is made to prevent contact with the masterwork.

In a control device according to an embodiment of the present disclosure, the magnitude determination unit includes a third calculation unit that calculates a third comparison angle based on the separation angle, and a reference angle that is calculated by the reference angle calculation unit. a third angle determination unit that determines whether or not the reference angle is greater than the third comparison angle, and the correction unit determines that the reference angle is greater than the third comparison angle, the correction amount for the separation angle is added to perform the third correction.

In the present disclosure, when the reference angle is greater than the third comparison angle, correction is made to prevent contact with the masterwork.

In the control device according to an embodiment of the present disclosure, the first comparison angle is an angle obtained by adding 180 degrees and the first addition angle and subtracting the separation angle.

In the present disclosure, the first comparative angle is based on 180 degrees plus the first additional angle, thus reliably preventing contact between the masterwork and the tool.

In the control device according to an embodiment of the present disclosure, the correction unit adds a value obtained by subtracting the reference angle from the first addition angle to the separation angle.

In the present disclosure, the correction unit calculates an appropriate correction amount to prevent contact with the masterwork.

In the control device according to an embodiment of the present disclosure, the second comparison angle is an angle obtained by adding a second addition angle to the separation angle.

In the present disclosure, a second addition angle is added to the separation angle to obtain a suitable second comparison angle.

In the control device according to an embodiment of the present disclosure, the correction unit adds a value obtained by subtracting the second comparison angle from the reference angle to the separation angle.

In the present disclosure, the correction unit calculates an appropriate correction amount to prevent contact with the masterwork.

In the control device according to an embodiment of the present disclosure, the third comparison angle is an angle obtained by subtracting a third addition angle from the separation angle.

The present disclosure subtracts the third addition angle from the separation angle to obtain a suitable third comparison angle.

In the control device according to an embodiment of the present disclosure, the correction unit adds a value obtained by subtracting the third comparison angle from the reference angle to the separation angle.

In the present disclosure, the correction unit calculates an appropriate correction amount to prevent contact with the masterwork.

A machining path generation method according to an embodiment of the present disclosure is an approach operation of a spindle to a peripheral edge of a masterwork along a reference path on the outer or inner peripheral side of the masterwork that is determined based on a plurality of reference points. and determines whether or not the tool attached to the spindle contacts the peripheral edge during the approaching operation, and if it is determined that the tool has contacted the peripheral edge, acquire the coordinates of the spindle, after obtaining the coordinates of the spindle, the separation motion of the spindle is performed in the separation angle direction which is a predetermined angle with respect to the reference path, the approach motion and the separation motion are performed, and the tool contacts the peripheral portion during the approach motion. In a machining path generation method for generating a machining path for the spindle based on a plurality of acquired coordinates, the angle formed by the acquired coordinates for the spindle and the coordinates for the reference point. to determine the size of the separation angle and a boundary angle that is 180 degrees or an angle based on the reference angle, and based on the judgment result, the separation angle and the separation angle based on a predetermined angle is corrected, and the separation operation is performed using the corrected separation angle.

In the present disclosure, the spindle moves toward and away from the peripheral edge of the masterwork along the reference path. When the tool touches the periphery during the approaching motion, the control device acquires the coordinates of the spindle and generates a machining path based on the coordinates. Also, the spindle is separated from the master work based on the separation angle based on the line connecting the current coordinates of the spindle and the coordinates of the reference point. If the separation angle needs to be corrected, that is, if there is a possibility of contact with the masterwork, the separation angle is corrected.

A computer program according to an embodiment of the present disclosure causes a spindle to approach a peripheral edge of a masterwork along a reference path on the outer or inner peripheral side of the masterwork determined based on a plurality of reference points. determining whether or not the tool attached to the spindle contacts the peripheral edge during the approaching operation, and if it is determined that the tool has contacted the peripheral edge, acquiring the coordinates of the spindle; is obtained, the separation motion of the spindle is performed in the separation angle direction which is a predetermined angle with respect to the reference path, the approach motion and the separation motion are performed, and each time the tool contacts the peripheral portion during the approach motion, , a computer program executable by a control device that acquires the coordinates of the spindle and generates a machining path of the spindle based on the acquired plurality of coordinates, wherein the control device stores the acquired coordinates of the spindle and the reference A reference angle, which is an angle formed by the coordinates of a point, is calculated, the magnitude of the separation angle and 180 degrees or a boundary angle, which is an angle based on the reference angle, is determined, and the separation angle and the predetermined angle are determined based on the determination result. The separation angle is corrected based on the determined angle, and the separation operation is performed using the corrected separation angle.

In the present disclosure, the spindle moves toward and away from the peripheral edge of the masterwork along the reference path. When the tool touches the periphery during the approaching motion, the control device acquires the coordinates of the spindle and generates a machining path based on the coordinates. Also, the spindle is separated from the master work based on the separation angle based on the line connecting the current coordinates of the spindle and the coordinates of the reference point. If the separation angle needs to be corrected, that is, if there is a possibility of contact with the masterwork, the separation angle is corrected.

In the control device, machining path generation method, and computer program according to an embodiment of the present disclosure, the spindle alternately approaches the peripheral edge of the masterwork and moves away from the peripheral edge along the reference path. repeat. When the tool comes into contact with the peripheral portion during the approaching operation, the control device acquires the coordinates of the spindle, accurately generates the machining path based on the coordinates, and can reduce the operator's correction work. Also, the spindle is separated from the master work based on the separation angle based on the line connecting the current coordinates of the spindle and the coordinates of the reference point located closest to the spindle. If the separation angle needs to be corrected, i.e., if there is a possibility of contact with the master work, the separation angle is corrected. It can reduce the correction work of the operator.

1 is a schematic perspective view of a machine tool; FIG. It is a block diagram which shows the structure of a machine tool. FIG. 4 is an explanatory diagram for explaining generation of a reference route; FIG. 4 is an explanatory diagram for explaining generation of a machining path; FIG. 5 is an explanatory diagram for explaining machining based on a machining path; It is an example of a display screen of a display unit. It is an explanatory view explaining a method of generating a machining path. FIG. 8 is a partially enlarged view of FIG. 7; It is a top view explaining an example of the first amendment. It is a top view explaining the other example of 1st correction|amendment. It is a top view explaining the second correction. It is a top view explaining the 3rd amendment. 5 is a flowchart for explaining machining path generation processing by a CPU; 5 is a flowchart for explaining correction processing by a CPU;

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below with reference to drawings showing a machine tool according to an embodiment. 1 is a schematic perspective view of a machine tool 1, and FIG. 2 is a block diagram showing the construction of the machine tool 1. As shown in FIG. In the following description, up, down, front, back, left, and right shown in the drawings are used.

A machine tool 1 includes a base 2 that is rectangular in plan view. A plurality of reinforcing cylinders 2a are formed on the upper surface of the base 2 in parallel with the top of the base 2. - 特許庁A holding table 3 is provided on a reinforcing tube 2a in the center of the base 2. As shown in FIG. The holding table 3 has a flat columnar shape and holds a work.

Three standing pillars 4 are provided around the holding base 3 . The vertical column 4 extends upward from the reinforcing tube 2a. The three standing pillars 4 are arranged with a phase interval of about 120 degrees in plan view. A track 5 is provided on the side surface of each standing pillar 4 on the holding base 3 side. The track 5 extends vertically.

A moving part 6 is provided on the track 5 . The track 5 is provided with a drive source, for example, a ball screw 14 and a moving shaft motor 13 (see FIG. 2). The moving part 6 is vertically movable along the track 5 by the ball screw 14 driven by the moving shaft motor 13 . That is, the moving part 6 can move in a direction crossing the first support plate 10, which will be described later.
A mounting portion for mounting a first link 11 and a second link 21, which will be described later, is provided on the side surface of the moving portion 6 on the holding table 3 side. The attachment part is, for example, a hole or a protrusion.

A first support plate 10 is arranged above the holding base 3 . The first support plate 10 has a triangular shape in plan view and is substantially parallel to the upper surface of the holding table 3 . Three sides of the first support plate 10 face the three vertical columns 4 respectively. That is, the three side portions correspond to the three moving portions 6, respectively. Each side portion and each moving portion 6 are connected by two parallel first links 11 . The first link 11 is rod-shaped. One ends of the two first links 11 are connected to both ends of the sides via rotatable joints 7 respectively. The other ends of the two first links 11 are connected to the moving part 6 via rotatable joints 7, respectively. The joint 7 is, for example, a universal joint.

The first support platen 10 holds a spindle 30 protruding upward and downward. The spindle 30 grips a tool 30a at its end. A second support plate 20 is arranged above the first support plate 10, and a connecting cylinder 8 whose axial direction is the vertical direction is provided between the first support plate 10 and the second support plate 20. - 特許庁The connecting tube 8 connects the first supporting board 10 and the second supporting board 20 . The connecting tube 8 integrates the first support plate 10 and the second support plate 20 .

The upper part of the main shaft 30 is inserted inside the connecting cylinder 8 and passes through the second support plate 20 . The second support plate 20 has a triangular shape in plan view and is substantially parallel to the first support plate 10 . Three side portions of the second support plate 20 face the three uprights 4 respectively. That is, the three side portions correspond to the three moving portions 6, respectively. Each side portion and each moving portion 6 are connected by two parallel second links 21 . The second link 21 is rod-shaped. One ends of the two second links 21 are connected to both ends of the sides via rotatable joints 7 respectively. The other ends of the two second links 21 are connected to the moving part 6 via rotatable joints 7 respectively. The joint 7 is, for example, a universal joint.

The connecting tube 8 has a hexagonal shape in plan view, and among the six side portions at the upper end of the connecting tube 8, three side portions adjacent to each other in the circumferential direction are connected to the three side portions of the second support plate 20. do. Of the six sides at the lower end of the connecting tube 8 , three sides adjacent to each other in the circumferential direction are connected to the three sides of the first support plate 10 .

When the three moving parts 6 are at the same height position, the main shaft 30 is positioned substantially right above the center of the holding base 3 . When the two moving parts 6 are in the same vertical position and the other moving part 6 moves lower than the two moving parts 6, the main shaft 30 moves downward without changing the vertical position. It moves horizontally toward the opposite side of the moving part 6 .

When the two moving parts 6 are in the same vertical position and the other moving part 6 moves higher than the two moving parts 6, the main shaft 30 moves upward without changing the vertical position. Towards the part 6, move horizontally. When the three moving parts 6 move vertically by the same distance, the main shaft 30 moves vertically. By combining these movements, the machine tool 1 positions the spindle 30 at desired vertical, front, rear, left and right positions.

The spindle 30 has a spindle motor 12 . The main shaft 30 positioned at the desired position is rotated by the drive of the main shaft motor 12, and the tool 30a mounted on the main shaft 30 processes the work held on the holding base 3. FIG.

As shown in FIG. 2, the control device 40 includes a CPU 41, a storage section 42, a RAM 43, an input/output interface 44, an operation section 45, and a display section 46. The CPU 41 controls operations of each part of the machine tool 1 . The storage unit 42 is a rewritable memory such as EPROM, EEPROM, or the like. The storage unit 42 stores a control program (not shown) for controlling the machine tool 1 , a machining program DB 421 storing a plurality of machining programs for machining the workpiece 95 , and a machining path generation program 422 . The machining path generation program 422 is a program for executing processing to generate a machining path, and is provided in a state stored in a computer-readable recording medium 423 such as a CD-ROM, DVD-ROM, USB memory, etc. It is stored in the storage unit 42 by installing it in the control device 40 . Alternatively, the machining path generation program 422 may be obtained from an external computer (not shown) connected to a communication network and stored in the storage unit 42 .

The storage unit 42 stores a threshold value, an additional angle, and the like for comparison with the torque of the spindle motor 12, which will be described later.

When the operator operates the operation unit 45 , a signal is input from the operation unit 45 to the input/output interface 44 . The operation unit 45 is, for example, a keyboard, buttons, touch panel, or the like. The input/output interface 44 outputs signals to the display section 46 . A display unit 46 is a liquid crystal display panel or the like, and displays characters, graphics, symbols, and the like.

The control device 40 further includes a torque detector 12a for detecting the torque of the spindle motor 12, a spindle control circuit 47 corresponding to the spindle motor 12, a servo amplifier 48, a movement axis control circuit 49 and a servo amplifier 50 corresponding to the movement axis motor 13. Prepare. Based on a command from the CPU 41 , the spindle control circuit 47 outputs to the servo amplifier 48 a command indicating target values such as the direction of rotation and the number of revolutions of the spindle motor 12 . The servo amplifier 48 supplies power to the spindle motor 12 based on the command. The torque detector 12 a detects the torque of the spindle motor 12 , and the CPU 41 acquires the torque via the input/output interface 44 . The encoder 18 detects the rotational position and speed of the spindle motor 12 and sends a detection signal to the servo amplifier 48 . A servo amplifier 48 compares the detection signal with a target value to control the power to be output.

Based on a command from the CPU 41 , the moving axis control circuit 49 outputs to the servo amplifier 50 commands indicating target values such as moving directions and speeds of the three moving parts 6 . The servo amplifier 50 supplies power to the moving axis motor 13 based on the command. The encoder 19 detects the rotational position and speed of the moving shaft motor 13 and sends a detection signal to the servo amplifier 50 . The servo amplifier 50 compares the detection signal with the target value and controls the output power.

3 is an explanatory diagram for explaining the generation of the reference path, FIG. 4 is an explanatory diagram for explaining the generation of the machining path, and FIG. 5 is an explanatory diagram for explaining machining based on the machining path. .
In the machining path generation method of this embodiment, the deburred master work 9 is held on the holding table 3 of the machine tool 1 . A tool 30 a is attached to the tip of the spindle 30 .
As shown in FIG. 3, a reference path _L0 is generated on the outer peripheral side of the masterwork 9 by a method such as online teaching using conventional CAM software. The reference path _L0 is taught by a plurality of teaching points _Pn (n is a natural number) on the reference path _L0 . A teaching point corresponds to a reference point. Along the reference path L ₀ based on the machining path generation program 422 , the spindle 30 alternately performs an approaching motion to the peripheral edge of the master work 9 and a moving away from the peripheral edge. The peripheral edge includes an outer peripheral edge and an inner peripheral edge. The approaching motion is the motion of approaching the masterwork 9 , and the separating motion is the motion of moving away from the masterwork 9 .

The CPU 41 determines whether or not the tool 30a contacts the peripheral portion during the approaching operation, and acquires the coordinates of the center P of the spindle 30 each time it determines that the tool 30a has contacted. The CPU 41 acquires the rotational position of the moving shaft motor 13 using the encoder 19 and calculates the coordinates of the center P of the main shaft 30 using the acquired rotational position. As shown in FIG. 4, the CPU 41 generates the machining path _L1 based on the obtained coordinates of the center P. As shown in FIG. When deburring a work 95 with burrs, the work 95 is held on the holding base 3 . As shown in FIG. 5, the workpiece 95 is machined by moving the spindle 30 with the tool 30a mounted thereon along the machining path _L1 based on the corresponding machining program.

FIG. 6 is an example of a display screen of the display unit 46. As shown in FIG. In order to generate the machining path L ₁ , the CPU 41 displays the master work, the teaching points P _n (n=1, 2, 3, . . . ), and the reference path L ₀ on the right side of the display screen. Or display as a plan view. The perspective view or plan view may be switched by the operator's operation. The CPU 41 displays input fields for the search pitch, the separation amount, and the movement amount during measurement on the left side of the display screen. Details of the search pitch, the separation amount, and the movement amount during measurement will be described later.

The operator confirms the reference route L ₀ displayed by the CPU 41 on the display unit 46, and if there is a portion of the reference route L ₀ to be corrected by the operation unit 45, it is indicated by an arrow. The operator inputs the search pitch, separation amount, and movement amount during measurement. Candidates for the search pitch, the separation amount, and the movement amount during measurement may be presented and selected by the operator.

The CPU 41 acquires the search pitch, separation amount, and movement amount at the time of measurement input by the operator, inputs the corrected portion when it is acquired, and sets search conditions such as reducing the search pitch for the corrected portion. do. Based on the set conditions, the CPU 41 generates the machining path _L1 .

FIG. 7 is an explanatory diagram for explaining the method of generating the machining path _L1 , and FIG. 8 is a partial enlarged view of FIG. The reference path L ₀ is the path initially stored in the machining program DB 421 . It has a plurality of teaching points P _n (n=1, 2, 3, . . . ) on the reference path L ₀ . The CPU 41 generates a search route T along which the main shaft 30 moves in a zigzag manner along the reference route L ₀ based on the set search pitch, separation amount, and movement amount during measurement. In FIG. 7, the point P _a is the center point of the main shaft 30 when it is separated, and the points P _1a , P _1b , P _1c , P _2a , P _2b , . 9 is the center point of the main shaft 30 when it comes into contact with it. A polygonal line connecting the point P _a and the center points P _1a , P _1b , P _1c , P _2a , P _2b , .

As shown in FIG. 7, the center point of spindle 30 moves from P ₀ to P ₁ , approaches masterwork 9 and contacts masterwork 9 . As shown in FIG. 8, the center point of the main shaft 30 at contact is _P1a . The CPU 41 generates a first vector a having a first length from the center point _P1a of the main shaft 30 toward the teaching point _P2 , and a second vector b having a second length and orthogonal to the first vector a. to calculate The first length is the search pitch in FIG. The second length is the separation amount in FIG. The coordinates of the point Pa are obtained by calculating the first vector a and the second vector b.

The CPU 41 calculates a third vector c, which is the sum of the first vector a and the second vector b, and separates the main shaft 30 based on the third vector c. By calculating the first vector a and the third vector c, the angle θ _a formed by the first vector a and the third vector c can be obtained. The angle θa is the separation angle. Alternatively, the angle θ _a may be stored in advance in the storage unit 42 or obtained, and the third vector c may be obtained so as to form the angle θ _a with respect to the vector a.

Next, based on a fourth vector d having a direction opposite to that of the second vector b and having a third length obtained by adding the movement amount during measurement (see FIG. 7) to the second length, the main shaft 30 is approached. Let The movement amount at the time of measurement is the distance added to the second length for the approach motion. Until the contact with the master work 9 is detected, the approach operation is performed aiming at the end point P _b of the fourth vector d inside the master work 9 . Actually, the main shaft 30 contacts the master work 9 before reaching the end point _Pb , and after the contact, the main shaft 30 does not move, and the moving shaft motor 13 rotates the necessary amount to reach the end point _Pb .

When the distance D between the center _P1c of the spindle 30 and the teaching point _P2 at the time of contact becomes less than the search pitch, from _P1c to the next teaching point _P3 , the first distance having the first length is reached. The principal axis 30 is spaced apart based on a third vector c which is the sum of vector a and a second vector b which is orthogonal to the first vector a and has a second length. In this manner, the CPU 41 alternately performs the separating operation and the contacting operation, and stores the coordinates of the center point of the main shaft 30 each time the main shaft 30 contacts the master work 9 during the approaching operation. The CPU 41 generates a machining path for the spindle 30 based on the stored coordinates.

FIG. 9 is a plan view explaining an example of the first correction. As shown in FIG. 9, the masterwork 9 has one side 9a and the other side 9b, and the one side 9a and the other side 9b form right-angled or acute-angled corners. When the spindle 30 moves near the corner, the CPU 41 performs the first correction. A point P _s1 in FIG. 9 is the position of the center point of the main shaft 30 when it contacts the master work 9, and is the current position (corresponding to the first coordinates). The point P _s0 is the position of the center point of the spindle 30 when it contacts the master work 9, and is the position (corresponding to the second coordinates) immediately before the point P _s1 . Points P _s0 and P _s1 correspond to points P _1a , P _1b , P _1c , P _2a , P _2b , . . . in FIG. Points P _k (k=2, 3, 4, . . . ) are taught points (corresponding to reference points in claim 2) corresponding to taught point P ₂ in FIG. It is a teaching point to do. The points P _s0 and P _s1 face the surface 9a and are arranged along the surface 9a. The teaching point P _k faces the other surface 9b. The taught point P _k is the taught point with the shortest distance from the point P _s1 . The teaching point P _k may be any teaching point ahead of the point P _s1 in the traveling direction of the spindle, and is not limited to the teaching point closest to the point P _s1 .

A point P _a in FIG. 9 is the center point of the main shaft 30 when separated, and is the same as the point P _a in FIGS. 7 and 8 . The point P _a ' is the center point of the main shaft 30 when separated, and is the center point after the first correction. θ is ∠P _s0 P _s1 P _k and is the reference angle. _θa is the separation angle between the line segment P _s1 P _k and the line segment P _s1 P _a . The separation angle θ _a and the first addition angle θ _c are stored in advance in the storage unit 42 . θ _e is the correction amount. L1 is a straight line passing through points P _s0 and P _s1 .

As described above, the CPU 41 separates the spindle 30 based on the third vector c. After separation, the center of main axis 30 is located at point P _a . That is, the main shaft 30 is separated in the direction (the direction of the third vector c) rotated counterclockwise by θ+ _θa with respect to the straight line L1.

When the main shaft 30 separates near the corner of the masterwork 9 , there is a possibility that it will come into contact with the masterwork 9 . If the angle θ+ _θa is greater than 180 degrees, the spindle 30 does not contact the masterwork 9 . In order to reliably avoid contact, an angle obtained by adding the first additional angle θ _c to 180 degrees is defined as the boundary angle. Boundary angle is the angle between contact and non-contact boundaries. That is, when the angle θ+ _θa is equal to or greater than 180 degrees+the first additional angle _θc , the spindle 30 does not contact the masterwork 9 . If the angle θ + θ _a < 180 degrees + the first additional angle θ _c , that is, if θ < 180 degrees + the first additional angle θ _c - θ _a , there is a possibility of contact with the master work 9 during separation. , the separation angle θ _a is subjected to the first correction. Since the main shaft 30 does not move in the direction opposite to the traveling direction, 0<θ. 180 degrees +θ _c -θ _a corresponds to the first comparison angle. Note that the first comparison angle may be obtained by multiplying 180 degrees by a predetermined coefficient.

In the first correction, the CPU 41 calculates the correction amount _θe . Since the angle obtained by adding the correction amount θ _e to θ+θ _a should be 180 degrees+first additional angle θ _c , θ+θ _a +θ _e =180 degrees+θ _c . Therefore, θ _e =180 degrees−θ−θ _a +θ _c . The CPU 41 adds _θe to _θa and executes the separation operation.

FIG. 10 is a plan view explaining another example of the first correction. In FIG. 10, the same components as in FIG. 9 are denoted by the same reference numerals, and detailed description thereof will be omitted. As shown in FIG. 10, the masterwork 9 has a curved surface 9c projecting in a predetermined direction. 9t is the vertex of the curved surface 9c, and L2 is the line passing through the vertex 9t. Point P _s0 and point P _s1 are located in one area bounded by line L2, and teaching point P _k is located in the other area.

As in the case of FIG. 9, when the angle θ+θ _a <180 degrees+first additional angle θ _c , there is a possibility that the masterwork 9 comes into contact with the separation angle θ _a . conduct. The CPU 41 calculates the correction amount θ _e and adds θ _e to θ _a .

FIG. 11 is a plan view explaining the second correction. In FIG. 11, the same components as in FIG. 9 are denoted by the same reference numerals, and detailed description thereof will be omitted. As shown in FIG. 11, the masterwork 9 is formed with narrow grooves 9d. The point P _s0 is located on one side surface 9d1 of the groove 9d, the point P _s1 is located on the end surface 9d3 of the groove 9d, and the teaching point P _k is located on the other side surface 9d2 of the groove 9d. One side 9d1 and the other side 9d2 face each other. Note that the point P _s1 may be located on one side 9d1 or the other side 9d2. θ is ∠P _k P _s1 P _s0 and is the reference angle. θ _d is the second addition angle. L3 is a straight line passing through points P _k and P _s1 .

As shown in FIG. 11, the main shaft 30 is separated in the direction rotated counterclockwise by _θa with respect to the straight line L3. If the angle θ _a <θ, the spindle 30 does not contact the masterwork 9 when separated. In order to reliably avoid contact, an angle obtained by subtracting the second additional angle _θd from θ is taken as the boundary angle. That is, when the angle θ _a is θ−θ _d or less, the spindle 30 does not contact the master work 9 . When θ _a >θ−θ _d , that is, when θ<θ _a +θ _d , there is a possibility that the spindle 30 will come into contact with the masterwork 9, so the separation angle θ _a is subjected to the second correction. Since the main shaft 30 does not move in the direction opposite to the traveling direction, 0<θ. θ _a +θ _d corresponds to the second comparison angle. Note that the second comparison angle may be obtained by multiplying θ _a by a predetermined coefficient.

In the second correction, the CPU 41 calculates the correction amount _θe . Since the angle obtained by adding the correction amount θ _e to θ _a should be θ−θ _d , θ _a +θ _e =θ−θ _d . Therefore, θ _e =θ−θ _a −θ _d =θ−(θ _a +θ _d )=−(θ _a +θ _d −θ). The CPU 41 adds _θe to _θa and executes the separation operation.

FIG. 12 is a plan view explaining the third correction. In FIG. 12, the same components as in FIGS. 9 to 11 are denoted by the same reference numerals, and detailed description thereof will be omitted. As shown in FIG. 12, the masterwork 9 is formed with a narrowed portion 9e cut at an acute angle. The taught point P _k is the taught point with the shortest distance from the point P _s1 . The taught point P _k+1 is the taught point with the second shortest distance from the point P _s1 . The point P _s1 is located on one side surface 9e1 of the narrow portion 9e. The teaching point _Pk is positioned at the corner of the narrow portion 9e. The teaching point Pk ₊₁ is positioned on the other side surface 9e2 of the narrow portion 9e. θ is ∠P _k P _s1 P _k+1 and is the reference angle. θ _f is the third addition angle. The taught points P _k and P _k+1 do not necessarily have the shortest distance, but the taught point P _k is the taught point P _k+1 . closer to point P _s1 than

As shown in FIG. 12, the main shaft 30 is separated in the direction rotated counterclockwise by _θa with respect to the straight line L3. If the angle θ _a >θ, the spindle 30 does not contact the masterwork 9 during separation. The boundary angle between contact and non-contact is θ. In order to reliably avoid contact, an angle obtained by adding a third additional angle θ _f to θ is defined as a boundary angle. That is, when the angle θ _a is θ+θ _f or more, the spindle 30 does not contact the master work 9 . When θ _a <θ+θ _f , that is, when θ>θ _a −θ _f , there is a possibility that the spindle 30 will come into contact with the master work 9, so the separation angle θ _a is subjected to the third correction. Since the main shaft 30 does not move in the direction opposite to the traveling direction, 180 degrees > θ. θ _a −θ _f corresponds to the third comparison angle. Note that the third comparison angle may be obtained by multiplying θ _a −θ _f by a predetermined coefficient.

In the third correction, the CPU 41 calculates the correction amount _θe . Since the angle obtained by adding the correction amount _θe to _θa should be θ+ _θf , _θa + _θe =θ+ _θf . Therefore, θ _e =θ+θ _f −θ _a =θ−(θ _a −θ _f ). The CPU 41 adds _θe to _θa and executes the separation operation.
In the first to third corrections, the reference angle, separation angle, and correction amount are stored in advance in the storage unit 42 in association with each other, and the CPU 41 acquires the separation angle and correction amount corresponding to the reference angle from the storage unit 42. may

FIG. 13 is a flowchart for explaining machining path generation processing by the CPU 41. As shown in FIG. The CPU 41 acquires the reference route L ₀ , search teaching points, correction teaching points, etc. (S1). The CPU 41 changes the machining program No. according to the operator's operation. , and refer to the machining program DB 421 to obtain the corresponding No. Acquire the reference path L ₀ in the machining path column of the machining program. Alternatively, the spindle 30 is moved to bring the tool 30a into contact with the master work 9, the coordinates of the point indicating the corner of the master work 9 and the point at which the attitude of the tool 30a changes are acquired, and based on these teaching points P _n , to obtain the reference path L ₀ . Also, a search teaching point, which is a teaching point for use in calculation of the search path, is acquired. In the initial state, the search teaching point is the teaching point _P2 .

The CPU 41 displays on the display unit 46 the reference route L ₀ and the input fields for the conditions of the search pitch, the separation amount, and the movement amount during measurement (S2, see FIG. 6). The CPU 41 acquires the search pitch, separation amount, and movement amount at the time of measurement input by the operator, inputs the corrected portion when it is acquired, and sets search conditions such as reducing the search pitch for the corrected portion. (S3).

The CPU 41 executes the approaching operation of the spindle 30 (S4), and determines whether or not the tool 30a has come into contact with the master work 9 (S5). The CPU 41 drives the moving shaft motor 13 to bring the main shaft 30 closer to the master work 9 while rotating the main shaft motor 12 at a low speed (forward or reverse rotation). A low speed is, for example, 100-1000 rpm. The CPU 41 determines whether or not the torque of the spindle motor 12 is greater than or equal to the threshold value stored in the storage unit 42, and determines that the tool 30a has come into contact with the master work 9 when the torque of the spindle motor 12 is greater than or equal to the threshold value.

When determining that the tool 30a is not in contact with the master work 9 (S5: NO), the CPU 41 returns the process to step S5. When determining that the tool 30a has come into contact with the master work 9 (S5: YES), the CPU 41 acquires the coordinates of the spindle 30, that is, the central coordinates of the spindle 30 (S6). The CPU 41 that executes step S5 corresponds to the contact determination section, and the CPU 41 that executes step S6 corresponds to the acquisition section.

The CPU 41 determines whether or not the distance D between the center of the spindle 30 at the time of contact and the search teaching point is less than the search pitch (S7). If the distance D is not less than the search pitch (S7: NO), the CPU 41 calculates the coordinates of the central point P _a of the main shaft 30 when separated (S9). If the distance D is less than the search pitch (S7: YES), the CPU 41 updates the search teaching point (S8), and proceeds to step S9. In step S8, for example, the CPU 41 updates the search teaching point from teaching point _P2 to teaching point _P3 .

After the processing of step S9, the CPU 41 calculates the reference angle θ (S10) and calculates the boundary angle (S11). The CPU 41 executes correction processing for the separation angle _θa (S12). Details of the correction processing will be described later. After the process of step S12, the CPU 41 executes the separation operation based on the corrected separation angle _θa (S13).

After the process of step S13, the CPU 41 determines whether or not the search for all center coordinates of the spindle 30 has been completed (S14). When determining that the search for all the center coordinates of the spindle 30 has not ended (S14: NO), the CPU 41 returns the process to step S4. When it is determined that the search for all the center coordinates of the spindle 30 has been completed (S14: YES), the CPU 41 generates a machining path based on the plurality of stored center coordinates, and stores the generated machining path in the storage unit 42. (S15), and the process ends.

FIG. 14 is a flowchart for explaining correction processing by the CPU 41. As shown in FIG. In step S12, the CPU 41 determines whether or not the boundary angle is greater than the sum of the reference angle θ and the separation angle _θa (S21). That is, the CPU 41 calculates the first comparison angle 180 degrees + θ _c - θ _a and determines whether or not the reference angle θ is smaller than 180 degrees + θ _c - θ _a (see Figs. 9 and 10). The CPU 41 that calculates 180 degrees + θ _c - _{θ a} corresponds to the first calculation unit, and the CPU 41 that determines whether or not the reference angle θ is smaller than 180 degrees + θ _c - θ _a corresponds to the first angle determination unit. . If it is determined that the boundary angle is greater than the sum of the reference angle θ and the separation angle θa (S21: YES), that is, if it is determined that the reference angle θ is smaller than 180 degrees + _θc - _θa , the CPU 41 determines the separation angle θ A first correction is performed on _a (S22). That is, the CPU 41 calculates the correction amount _.theta.e and adds the calculated correction amount _.theta.e to the separation angle .theta.a. θ _e is 180 degrees−θ−θ _a +θ _c . The separation angle θa may be calculated, stored in advance in the storage unit 42, input using the operation unit 45, or set by a machining program. The CPU 41 that executes S22 corresponds to the correction section.

If it is determined that the boundary angle is not greater than the sum of the reference angle θ and the separation angle θa (S21: NO), that is, if it is determined that the reference angle θ is 180°+ _θc − _θa or more, the CPU 41 determines the boundary angle. is smaller than the separation angle .theta.a (S23). That is, the CPU 41 calculates the second comparison angle θ _a +θ _d and determines whether or not the reference angle θ is smaller than θ _a +θ _d (see FIG. 11). The CPU 41 that calculates θ _a +θ _d corresponds to the second calculation unit, and the CPU 41 that determines whether the reference angle θ is smaller than θ _a +θ _d corresponds to the second angle determination unit. If it is determined that the boundary angle is smaller than the separation angle θa (S23: YES), that is, if it is determined that the reference angle θ is smaller than _θa + _θd , the CPU 41 executes the second correction for the separation angle _θa . (S24). That is, the CPU 41 calculates the correction amount _.theta.e and adds the calculated correction amount _.theta.e to the separation angle .theta.a. θ _e is θ−θ _a −θ _d . The CPU 41 that executes S24 corresponds to the correction section.

When it is determined that the boundary angle is not smaller than the separation angle θa (S23: NO), that is, when it is determined that the reference angle θ is equal to or greater than _θa + _θd , the CPU 41 determines whether the boundary angle is larger than the separation angle θa. (S25). That is, the CPU 41 calculates the third comparison angle θ _a -θ _f and determines whether or not the reference angle θ is greater than θ _a -θ _f (see FIG. 12). The CPU 41 that calculates θ _a −θ _f corresponds to the third calculation section, and the CPU 41 that determines whether or not the reference angle θ is greater than θ _a −θ _f corresponds to the third angle determination section. If it is determined that the boundary angle is greater than the separation angle θa (S25: YES), that is, if it is determined that the reference angle θ is greater than θa _{− θf} , the CPU 41 performs the third correction to the separation angle _θa . Execute (S26). That is, the CPU 41 calculates the correction amount _.theta.e 21 and adds the calculated correction amount _.theta.e to the separation angle .theta.a. θ _e is θ+θ _f −θ _a . The CPU 41 that executes S26 corresponds to the correction unit.

When it is determined that the third correction is not necessary (S25: NO), or after the process of step S22, S24, or S26, the CPU 41 executes the separating operation (S13).

In the machine tool according to the embodiment, the spindle 30 alternately repeats the approaching motion to the peripheral edge of the masterwork 9 and the moving away from the peripheral edge along the reference path _L0 . When the tool 30a comes into contact with the peripheral portion during the approaching operation, the machine tool 1 acquires the coordinates of the spindle 30, accurately generates the machining path _L1 based on the coordinates, and can reduce operator's correction work. Also, a reference angle formed by the current coordinates of the main shaft 30 and the coordinates of the reference point is calculated, and the magnitude of the separation angle _θa , which is the direction of the separation operation, and 180 degrees or the boundary angle, which is an angle based on the reference angle, is determined. Then, the separation angle _θa is corrected based on the determination result. When the separation angle _θa needs to be corrected, that is, when there is a possibility of contact with the master work 9, the separation angle _θa is corrected to prevent the spindle 30 from interfering with the master work 9 during the separation operation. This can be automatically prevented and the operator's correction work can be reduced.

Further, since the reference angle is calculated based on the first coordinate, the second coordinate, and the reference point at which the masterwork 9 and 30a contact, the reference angle becomes more faithful to the shape of the masterwork 9. FIG.
When the reference angle θ is 180 degrees + θ _c - θ _a , that is, smaller than the first comparison angle, the first correction is performed to prevent contact with the masterwork 9 . Also, in the first correction, a correction amount θ _e =180 degrees−θ−θ _a +θ _c is calculated to prevent contact with the master work 9 .
Since the comparison angle is the addition of the first additional angle _θc , the contact of the tool 30a with the master work 9 can be reliably prevented.

When the reference angle θ is smaller than θ _a +θ _d , that is, the second comparison angle, the second correction is performed to prevent contact with the masterwork 9 . Also, in the second correction, a correction amount θ _e =−(θ _a +θ _d −θ) is calculated to prevent contact with the master work 9 . Since the second additional angle _.theta.d is added to the comparative angle, the contact of the tool 30a with the master work 9 can be reliably prevented.

Further, when the reference angle θ is θ _a −θ _f , that is, when it is larger than the third comparison angle, the third correction is performed to prevent contact with the master work 9 . Also, in the second correction, a correction amount θ _e =θ−θ _a +θ _f is calculated to prevent contact with the masterwork 9 . Since the comparative angle subtracts the third additional angle _θf , the contact of the tool 30a with the master work 9 is reliably prevented.
CPU41 which performs S4 corresponds to a 1st moving part, and CPU41 which performs S14 corresponds to a 2nd moving part. In S10, the first correction and the second correction are performed with the position P s1 of the center of the spindle 30 that is currently in contact with the master work 9 as the apex, and the position P _s1 of the center of the spindle 30 that was in contact with the master work 9 before (past). A reference angle is calculated using _s0 and the subsequent taught point _Pk . In the third correction, the position P _s1 of the center of the spindle 30 currently in contact with the master work 9 is set as the vertex, and the reference angle is calculated using two teaching points P _k after that.

The embodiments disclosed this time should be considered as examples in all respects and not restrictive. The technical features described in each embodiment can be combined with each other, and the scope of the present invention is intended to include all modifications within the scope of the claims and the scope of equivalents to the scope of the claims. be done.

Reference Signs List 1 machine tool 6 moving unit 30 spindle 30a tool 40 control device 41 CPU
42 storage unit 43 RAM

Claims (13)

a first moving unit that performs an approaching motion of the spindle for mounting the tool to the peripheral edge of the masterwork along a reference path on the outer or inner peripheral side of the masterwork that is determined based on a plurality of reference points;
a contact determination unit that determines whether or not the tool has come into contact with the peripheral portion during the approaching operation by the first moving unit;
an acquisition unit that acquires the coordinates of the main axis when the contact determination unit determines that there is contact;
a second moving unit that separates the main shaft in a separation angle direction that is a predetermined angle with respect to the reference path after the acquisition unit acquires the coordinates of the main shaft;
An approaching operation by the first moving part and a separating operation by the second moving part are performed, and each time the tool contacts the peripheral part during the approaching operation, the coordinates of the main axis are acquired, and based on the acquired plural coordinates , in a numerical control device that generates a machining path for the spindle,
a reference angle calculation unit that calculates a reference angle that is an angle formed by the coordinates of the main axis and the coordinates of the reference point obtained by the acquisition unit;
a magnitude determination unit that determines the magnitude of the separation angle and a boundary angle that is 180 degrees or an angle based on the reference angle calculated by the reference angle calculation unit;
a correction unit that corrects the separation angle based on the separation angle and a predetermined angle based on the determination result of the size determination unit;
The control device, wherein the second movement section performs a separation operation using the separation angle corrected by the correction section. The reference angle calculation unit obtains the first coordinates of the main axis obtained by the obtaining unit, the second coordinates of the main axis obtained by the obtaining unit before obtaining the first coordinates, and the coordinates obtained by the obtaining unit. 2. The control device according to claim 1, wherein an angle formed with the reference point after the calculation is calculated. The size determination unit is
a first calculation unit that calculates a first comparison angle based on 180 degrees;
a first angle determination unit that determines whether the reference angle calculated by the reference angle calculation unit is smaller than the first comparison angle,
2. When the first angle determination unit determines that the reference angle is smaller than the first comparison angle, the correction unit performs the first correction by adding a correction amount to the separation angle. Or the control device according to 2. The size determination unit is
a second calculation unit that calculates a second comparison angle based on the separation angle;
a second angle determination unit that determines whether the reference angle calculated by the reference angle calculation unit is smaller than the second comparison angle,
3. The control device according to claim 1, wherein, when determining that the reference angle is smaller than the second comparison angle, the correction unit performs a second correction by adding a correction amount to the separation angle. The size determination unit is
a third computing unit that computes a third comparison angle based on the separation angle;
a third angle determination unit that determines whether the reference angle calculated by the reference angle calculation unit is greater than the third comparison angle,
3. The control device according to claim 2, wherein the correction unit performs a third correction on the separation angle when determining that the reference angle is larger than the third comparison angle. The control device according to claim 3, wherein the first comparative angle is an angle obtained by adding 180 degrees and the first additional angle and subtracting the separation angle. The control device according to claim 6, wherein the correction unit adds a value obtained by subtracting the reference angle from the first addition angle to the separation angle. 5. The control device according to claim 4, wherein the second comparison angle is an angle obtained by adding a second addition angle to the separation angle. The control device according to claim 8, wherein the correction unit adds a value obtained by subtracting the second comparison angle from the reference angle to the separation angle. The control device according to claim 5, wherein the third comparison angle is an angle obtained by subtracting a third addition angle from the separation angle. The control device according to claim 10, wherein the correction unit adds a value obtained by subtracting the third comparison angle from the reference angle to the separation angle. The spindle is moved toward the peripheral edge of the masterwork along a reference path on the outer or inner circumference of the masterwork determined based on a plurality of reference points, and the tool attached to the spindle moves during the approaching movement. It is determined whether or not the tool is in contact with the peripheral edge, and if it is determined that the tool has contacted the peripheral edge, the coordinates of the main axis are obtained, and after obtaining the coordinates of the main axis, a predetermined The separation motion of the spindle is performed in a separation angle direction, the approach motion and the separation motion are performed, and the coordinates of the spindle are acquired each time the tool contacts the peripheral portion during the approach motion, and the acquired plurality of In the machining path generation method for generating the machining path of the spindle based on the coordinates of
calculating a reference angle that is an angle formed by the acquired coordinates of the principal axis and the coordinates of the reference point;
Determining the magnitude of the separation angle and a boundary angle that is 180 degrees or an angle based on the reference angle,
correcting the separation angle based on the separation angle and a predetermined angle based on the determination result;
A machining path generation method, wherein a separation operation is performed using the corrected separation angle. The spindle is moved toward the peripheral edge of the masterwork along a reference path on the outer or inner circumference of the masterwork determined based on a plurality of reference points, and the tool attached to the spindle moves during the approaching movement. It is determined whether or not the tool is in contact with the peripheral edge, and if it is determined that the tool has contacted the peripheral edge, the coordinates of the main axis are obtained, and after obtaining the coordinates of the main axis, a predetermined The separation motion of the spindle is performed in a separation angle direction, the approach motion and the separation motion are performed, and the coordinates of the spindle are acquired each time the tool contacts the peripheral portion during the approach motion, and the acquired plurality of In a computer program executable by a control device that generates a machining path for the spindle based on the coordinates of
to the control device,
calculating a reference angle that is an angle formed by the acquired coordinates of the principal axis and the coordinates of the reference point;
Determining the size of the separation angle and a boundary angle that is an angle based on 180 degrees or the reference angle,
correcting the separation angle based on the separation angle and a predetermined angle based on the determination result;
A computer program for executing a process of performing a separation operation using the corrected separation angle.

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