JP2517581B2 - Machining line teaching method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a machining line teaching method for a machining apparatus that cuts or welds along a machining line of a workpiece, and particularly, automatically measures machining line coordinates and The present invention relates to a machining line teaching method in which teaching is performed based on measurement data and retries are performed while changing the pitch according to the state of the machining line.

[Prior Art] It has been well known that a workpiece is cut or welded using a laser beam or the like. In this type of processing apparatus, a teaching playback method is used in which a processing line on a work is taught in advance and the processing is performed as it is normally. An operator normally drives the processing machine body by manual control. I am teaching.

FIG. 5 is a block diagram showing a conventional processing apparatus. In the figure, (10) is a main body of a processing machine that can be moved three-dimensionally, and a plurality of processing machines (for example, 5 corresponding to 5 axes of X to Z, α and β) are provided.
Individual motors (not shown) and resolvers (not shown) individually provided to these motors. Then, these resolvers are driven end portions of the processing machine body (10), that is, arm tip portions (10a) based on the rotational position of each motor.
The position detection signal L indicating the position and the posture of is output.

(11) is a processing head attached to the arm tip (10a).

Reference numeral (30) is an NC control unit for driving the processing machine main body (10), which is provided with a CPU, a memory, a plurality of interfaces and the like (all not shown), to which the position detection signal L is input and the arm tip ( Drive signal M for positioning 10a)
Is output.

(60) is an operation panel equipped with a display, a keyboard, operation switches, etc. (all not shown), and provides initial setting commands and operation commands for driving the processing machine body (10).
It is designed to be input to the NC control section (30).

Reference numeral (70) is a teaching box composed of a handheld keyboard, which can input drive commands for the processing machine body (10) to the NC control unit (30) by manual operation.

Next, the operation of the conventional machining line teaching method using the machining device of FIG. 5 will be described.

First, scoring K along the machining line of the work (not shown)
Give. Next, the machining head (11) attached to the arm tip (10a) irradiates the work with visible light (see the broken line), and visually confirms the light spot of this visible light along the score K. Move the machining head (11). At this time, the drive signal M is input to the processing machine body (10) by operating the teaching box (70) connected to the NC control unit (30).

Then, while sequentially positioning at points on the scoring K, operate the teaching box (70) to give a data input command to the NC control unit (30) to teach (teach) the measurement point data one by one. .

The above teaching operation requires inputting about 1000 points, which usually takes several hours, although it depends on the shape and length of the machining line.

From the measurement point data obtained in this way, NC control unit (30)
Calculates the machining line coordinates, generates a machining program, drives the machining machine body (10), and executes a predetermined machining operation.

[Problems to be Solved by the Invention] As described above, in the conventional processing machine teaching method, since the input of the processing line is performed manually by the operator, there is a problem that much time and labor are required. there were.

The present invention has been made to solve the above problems, and performs machining measurement of the machining line coordinates and automatically teaches, and when normal scanning measurement cannot be performed, the pitch is changed and the retry is performed. The purpose is to obtain a possible processing line teaching method.

[Means for Solving Problems] In the machining line teaching method according to the present invention, a singular line is provided along a machining line of a workpiece, and an optic line is provided on an arm tip portion of a processing machine body that follows the singular line to perform a weaving operation. Type sensor head, and a scanning measurement step for measuring the singular line based on the coordinates of the intersection of the light spot emitted from this sensor head and the singular line, and the sensor head detects the singular line by a normal weaving operation. When the scanning measurement cannot be performed, a retry step for changing the pitch and performing the initial weaving operation is provided.

[Operation] In the present invention, the sensor head automatically tracks the singular line on the machining line, and if the singular line cannot be measured by the normal weaving operation due to the positional relationship and the posture relationship between the sensor head and the workpiece, the pitch is measured. To change to retry operation.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a processing apparatus used in an embodiment of the present invention, in which (30A) corresponds to the NC control section (30) described above, and (10), (10a), (60), (70), M and L
Is the same as described above.

T is a singular line provided along the working line of the work, and is made of, for example, a 0.4 mm wide non-reflective black tape attached on the working line.

(20) is a sensor head attached to the arm tip (10a) of the processing machine body (10), which is a semiconductor laser that emits infrared laser light (see broken lines) and laser light that is diffusely reflected on the surface of the workpiece. And a signal processing unit (all not shown) for outputting the height detection signal H and the singular line detection signal D based on the signal obtained by the light receiving element. The signal processing unit in the sensor head (20) inputs a control signal for keeping the amount of received light constant to a semiconductor laser drive circuit (not shown), and a sharp rise of this control signal A non-reflective singular line T, for example, a singular line detection signal D indicating the presence of a black tape is output.

Reference numeral (40) is a copying measurement calculation unit including a CPU, a memory, a plurality of interfaces and the like (all not shown), and the position detection signal L from the processing machine body (10) and the height from the sensor head (20). Based on the detection signal H and the singular line detection signal D, a singular line position coordinate signal C consisting of measurement point data indicating the coordinates of the singular line T is output and used for weaving operation for detecting the singular line T while scanning. The weaving coordinate signal W is output to the NC control unit (30A).

(50) is a NC control section (30) for the machining program R based on the singular line position coordinate signal C from the scanning measurement calculation section (40).
A) is a data processing unit that outputs to a CPU, external memory,
A keyboard as an input terminal and a printer or the like as an output terminal (all not shown) are provided.

Next, referring to the flowchart of FIG. 2 and the explanatory diagrams of FIGS. 3 and 4 showing the weaving operation for singular line scanning measurement, one embodiment of the present invention using the processing apparatus of FIG. Will be described.

First, the singular line T is formed on the machining line of the work, and the optical sensor head (2
0) is provided. At the same time, the copying measurement (teaching) mode is selected by the operation panel (60), and the NC control unit (30A) is set to the copying measurement mode.

Next, by manually operating the teaching box (70), the starting point P _S , the direction indicating point P _D and the ending point P _E of the singular line T
While inputting (teaching), weaving width WD (usually,
Initially set the pitch l (usually several mm) for weaving operation (about 10 mm) (step S1).

Then, the start button (not shown) of the operation panel (60) is pressed to execute the scanning measurement for automatic teaching (step S2).

First, the sensor head (20) starts from the irradiation point of laser light.
The first point is a point that is moved by a predetermined amount after the intersection point P ₁ with the singular line T is detected by moving it from P _{S in the} direction perpendicular to the direction indicator point P _D.
Let weaving point Q ₁ of. Next, it is folded back along a straight line connecting the starting point P _S and the first weaving point Q ₁ (in the drawing, they are shown separated for convenience, but the intersection point P ₁ ′ coincides with the intersection point P ₁ ) and a predetermined amount The moved point (corresponding to the weaving width WD) is defined as the second weaving point Q ₂ . Thus, the first intersection P ₁ is detected by the first pair of weaving points Q ₁ and Q ₂ .

Next, the light spot from the sensor head (20) inclines toward the direction indicating point P _D, and the third weaving point Q ₃
Go to Hereinafter, the sensor head (20) sequentially folds back to the next weaving points Q ₃ , Q ₄ , ... And traces the singular line T until it reaches the vicinity of the end point P _E and intersects with the singular line T.
It continues to detect the P ₁ ~Pn.

The scanning measurement operation by weaving is automatically executed while keeping the height from the sensor head (20) to the work constant and keeping the angle of the sensor head (20) perpendicular to the work surface. The control is performed by the NC control unit (30A) via the processing machine body (10).
That is, the scanning measurement calculation unit (40), based on the singular line detection signal D, the height detection signal H, and the position detection signal L, coordinates (measurement point data) of the intersection Pi between the light spot and the singular line T and weaving. The coordinates of the point Qi are calculated, and further, the coordinates of the next weaving point Qi ₊₁ are calculated based on these coordinates and the weaving pattern stored in advance, and this is used as the weaving coordinate signal W in the NC control unit (30A). Output. The NC control unit (30A) uses the weaving coordinate signal W to determine 2
Interpolate between two weaving points Qi and Qi ₊₁ (eg 1 cm
(About 20 points with respect to the weaving width WD of the above), and the drive signal M based on the interpolated coordinates is sequentially output. Therefore, the sensor head (20) can always move while its position and orientation are controlled.

During this copy measurement operation, the CP in the copy measurement calculation unit (40)
U determines whether the sensor head (20) can measure the singular line T by a normal weaving operation (step S3),
If measurement is possible, continue scanning measurement (step S
2).

However, when the surface area of the work surface or the singular line T becomes equal to or more than the allowable value as shown in FIG. 4, the weaving progress (arrow A) direction after measuring the intersection point Pi is determined by the intersection points Pi _-1 and Pi. Therefore, even if the light spot moves from the weaving point Qi ₊₁ to Qi ₊₂ , the intersection with the singular line T cannot be obtained. Therefore, in normal weaving operation, the sensor head (2
0) cannot trace and measure the singular line T. In this case, the pitch is changed and a retry is performed to perform the initial weaving operation (step S4).

First, the retry number CR indicating the number of times of retry execution is initialized to 0, the retry pitch lR is set to l / 2, and the predetermined number CRM indicating the upper limit of the number of retries is initially set to 4 (normally several times) (first
Step S41). Then, the light spot position is moved to the retry start point P _R separated from the previous intersection point Pi by the retry pitch l _R in the arrow direction (second step S42). next,
The light spot is moved in the direction perpendicular to the arrow A (see the alternate long and two short dashes line in FIG. 4), the above-mentioned initial weaving operation is executed (third step S43), and it is determined whether or not the singular line T is detected ( Fourth step S44).

Here, if the singular line T is not detected,
It is determined whether or not the retry number CR is larger than the predetermined number CRM (fifth step S45). And the number of retries CR is a predetermined number C
If RM or less, the number of retries CR is incremented to CR + 1 and the retry pitch lR is halved to lR / 2
The process returns to step S42 (sixth step S46).

On the other hand, when it is determined that the singular line T is detected in the fourth step S44, the measured intersection point is set to Pi ₊₁ (7th step).
In step S47), the next weaving point Qi _{+ 2} 'is obtained (eighth step S48), and the process returns to the scanning measurement step S2. The weaving point Qi ₊₂ ′ is determined based on the weaving pattern used in the normal weaving operation, with the direction of arrow B as the weaving advancing direction.

If it is determined in the fifth step S45 that the number of retries CR is larger than the predetermined number CRM, the singular line T is determined to be abnormal, and the retry execution is terminated. If the singular line T is missing, the singular line T is reset, and if the automatic scanning measurement is impossible, the intersection is manually taught. That is, the processing machine main body (10) is driven through the teaching box (70), and the intersection of the light spot and the singular line T is input as a teaching point to the scanning measurement calculation section (40). At this time,
Similar to the normal weaving operation, the processing machine body (10) is driven so that the light spot crosses the singular line T. After that, the process returns to step S2 again, and the scanning measurement is automatically performed.

Thus, when the scanning measurement is completed, the singular line position coordinate signal C consisting of a series of measurement point data is transmitted to the data processing unit (50), and the CPU in the data processing unit (50)
It is determined whether or not the teaching of the machining line for one work is completed, and if it is not completed, the copying measurement calculation section (40) is caused to execute the copying measurement step S2. If the processing has been completed completely, the machining program R for machining the workpiece is calculated based on each measurement point data in the singular line position coordinate signal C, and this is transmitted to the NC control unit (30A).

Thereafter, similarly to the above, the machining head (11) is attached to the arm tip portion (10a) and a predetermined machining operation according to the machining program R is executed.

Although the singular line detection signal D is obtained by using the control signal of the signal processing unit in the above embodiment, the light amount signal may be used as it is as the singular line detection signal D.

Further, the sensor head (20) is provided at the arm tip (10a), but only the light receiving element is provided near the processing head (11) so that the visible light selectively emitted from the processing head is received. Good. In this case, the sensor head (20)
It is not necessary to attach it to.

[Effect of the Invention] As described above, according to the present invention, the singular line is provided along the machining line of the workpiece, and the optical sensor head is provided at the tip of the arm of the processing machine main body that performs the weaving operation along the singular line. , A scanning measurement step for measuring the singular line based on the coordinates of the intersection of the light spot emitted from this sensor head and the singular line, and when the sensor head cannot scan and measure the singular line by the normal weaving operation, And a retry step for performing the initial weaving operation, the sensor head automatically tracks the singular line on the machining line, and the normal weaving operation is performed depending on the positional relationship and posture relationship between the sensor head and the workpiece. If the line cannot be scanned and measured, the pitch is changed and the retry is executed. In addition, there is an effect that a machining line teaching method can be obtained in which a teaching point can be surely obtained regardless of the shape of the singular line.

[Brief description of drawings]

FIG. 1 is a block diagram showing a processing apparatus used in an embodiment of the present invention, FIG. 2 is a flow chart for explaining an embodiment of the present invention, and FIG. 3 is a scanning measurement of a sensor head in the present invention. FIG. 4 is an explanatory view showing the operation, FIG. 4 is an explanatory view showing the retry operation according to the present invention, and FIG. 5 is a block diagram showing the processing apparatus used in the conventional processing line teaching method. (10) …… Processing machine main body, (10a) …… Arm tip (20) …… Sensor head, T …… Singular line l …… Normal weaving pitch P _{1 to} Pn …… Intersection point, P _R …… Retry Start point CR …… Retry number, lR …… Retry pitch CRM …… Predetermined number S2 …… Copy measurement step, S4 …… Retry step S41 …… First step, S42 …… Second step S43 …… Third step, S44 ... Fourth step S45 ... Fifth step, S46 ... Sixth step In the drawings, the same reference numerals indicate the same or corresponding portions.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical display location B23Q 35/12 B23Q 35/12 A G05B 19/42 G05B 19/42 D

Claims (2)

(57) [Claims] 1. A singular line is provided along a machining line of a work, and an optical sensor head is provided at an arm tip portion of a processing machine main body that performs a weaving operation along the singular line, and irradiation is performed from this sensor head. A scanning measurement step for measuring the singular line based on the coordinates of the intersection of the light spot and the singular line, and when the sensor head cannot scan and measure the singular line by a normal weaving operation,
A machining line teaching method including a retry step for changing a pitch and performing an initial weaving operation. 2. The retry step comprises a first step of setting the number of retries, a retry pitch, and a predetermined number, a second step of moving to a retry start point separated from the previously measured intersection point by the retry pitch, and initial weaving. A third step of executing the operation, a fourth step of determining whether a singular line is detected, and a fourth step of determining whether the number of retries is larger than a predetermined number when the singular line is not detected. A fifth step, and a sixth step of incrementing the retry number and halving the retry pitch and returning to the second step when the retry number is less than or equal to the predetermined number The processing line teaching method according to the first section.