JPS59209482A - Position measuring device of material to be welded in pulse welding - Google Patents

Abstract

PURPOSE:To provide a titled device which measures exactly the position of materials to be welded with signal processing of simple circuits by the constitution in which the sectional images of the materials to be welded by the two slit rays obtd. during the dark time of an arc are separately taken into a control device and that the correlative relation of both sectional images is decided. CONSTITUTION:A position measuring device is constituted of an image pickup device 3 consisting of light emitting sources 4a, 4b, an electronic shutter 22, a lens 23, an image sensing element 24 and a control device 6, etc. Slit rays 15a, 15b are irradiated respectively from the two light sources 4a, 4b to the groove 2 of materials 1 to be welded, and the welding arc light is detected by a photodetector 5. The detection signal is inputted via an amplifier 9 to a timing genenerator 10 which controls driving circuits 11, 12 to output the sectional image during the dark time of the arc pulse to the device 6. The device 6 takes separately the two sectional images therein, stores the images in a storage circuit 13 and discriminates the correlative relation between the two sectional images with a computer 14 thereby measuring the position of the materials 1.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a pulse i for irradiating a workpiece with a slit-shaped beam, and measuring the posture, etc. of the workpiece using a cut image of the slit-shaped beam. The present invention relates to an apparatus for measuring the posture of a workpiece during welding.

Currently, a method using optical cutting is known as a non-contact measurement method.

This is done by irradiating the object to be measured with a slit-shaped light beam (a planar light beam, a point beam arranged on the same plane, a point beam scanned in the same plane). The cut image obtained above is observed from the oblique direction of the slit-shaped light beam, and the shape of the cut image is observed to judge the shape of the object to be measured.

However, in the conventional light cutting method using a slit-shaped beam,
The shape of the cut image changes due to the mutual relationship between the object to be measured and the slit-shaped light beam, for example, if the object to be measured is tilted with respect to the light beam, making it difficult to perform accurate measurements and reducing the amount of information obtained. It was not possible to judge the attitude of the object to be measured.

In addition, this light cutting is greatly influenced by background light, and when the background light is strong, it becomes difficult to separate the slit-shaped light beam (signal light) from the background light, and the reliability of the signal decreases.

Furthermore, it is difficult to use the optical cutting method to measure a workpiece in a welding chamber (although the arc light is so strong that it is virtually impossible to measure it).

This invention is! In view of the current situation, we have developed a sensor that automatically welds the optical cutting method by dividing it by 1, making it possible to measure the workpiece by optical cutting, especially the workpiece during welding, and also measuring the posture of the workpiece. It can be used as a sensor in

The present invention will now be described in detail with reference to the drawings.

In the figure, 1 is an object to be welded having a groove groove 2 (hereinafter referred to as a workpiece), 3 is an imaging device, 4a and 4b are a light emitting source that emits a slit-shaped light beam (hereinafter referred to as a slit beam),
Reference numeral 5 indicates a light detector, and reference numeral 6 indicates a control circuit 1'. The main components of the control device 6 are a filter 7, an AD converter 8, an amplifier 9, a timing generation As1O5 light source drive circuit 11, and a shutter drive circuit. 12, storage circuit 13, computer 14, synchronization (11υ division circuit 30).

In the present invention, two slit beams 'fj, 15a, 15b are applied to the workpiece 1! .

A mechanical connection that totals W, etc. will be explained.

Slit beams 15a, 15 from light sources 4a, 4b
The slit beams 15a and 15b intersect with each other on the side of the imaging device 3, and the cut images 16a and 16 obtained by the slit beams 15a and 15b are
b is as shown in FIG.
llI) indicates the longitudinal direction of 2, and the ■direction (■sal 1) indicates the direction perpendicular to 7 2゛.

Specifically, FIGS. 2 and 3 show the relationship between the cut images 16a and 16b, and the relationship between the slit beams 15a and 15b and the workpiece 1.

In the figure, Dll, the optical unit 17 of the imaging device 3 and the workpiece 1
Distance from 6, H direction middle/b line of optical unit 17 and groove l/I
'i2 Angle with longitudinal direction, Q: 'JR1i' Displacement between M center (image center) and fixed center of workpiece 1, ψ5, optical axis of optical unit 17 and 15+1 ahead IM2
σ is the angle between the optical axis and the bisector of the groove groove 2 and the groove angle 2θ7, U is the angle between the optical axis and the slit rays 15a and 15b, HC9 screen H axis Coordinates of the center of the H axis, ■ 1 screen ■ Coordinates of the 11th axis, R2, Wa, ψ month (1i m V 1i of the bending point of 16a
Coordinates of To, R2, yo, H-axis coordinates of the lTl1 curve point of the cut image 16a, Rovl, V-direction coordinates of the curve point of the January image 16b, R13!1: "J month jIi ('l/ 1
6b (f) Coordinate of bending point in H direction, V: l'ii mark ■
From' two arbitrary coordinates, V:)'V mark V from 1ζ
Coordinates of 6mi, n:H'; Coordinates H at mark V
Distance from 6 to cutting 1 elephant 16a, town 5 rin 4! rf Distance from coordinate H6 at V+J+ to cutting 1'η16a, II 11,'P4'l 6 Vrb Ni 7
+l'u mark H6 force) Cut 1 analysis (distance to η16b, In,, : Coordinates HC at I!fi mark ■77.
Force) Distance from r cut 1 analysis 1 elephant 16b, dwA1 Distance from mark HC to bending point RAH, dWB
yrx mt from seat el Hc to bending point R111+
, Od, slit ray 15a from L level O to base.

15b intersects, DW, distance from 0 to workpiece fAt, D, p, Dp: distance from 0,1 to workpiece, D6 is Dw<
od, D; is when D w > 01.

Next, the calculation of d)5, Qd, etc. will be explained in the first order of il'.

(1) First, regarding the small, Fig. 4 shows the cut images 16a and 16b when Oi>Dw, and Fig. 5 shows the cut images 16a and 16b when Od<Dw. PUX: Can be easily determined from the mark. That is, it can be found by (RAV REV ) (RAH'
−RB□, ) ((13, From the positive/negative judgment, the positive/negative and DW force of d)) can be found.

(ii) Regarding Qd, fad is obtained by /(L-(Vo-RAv(OrRBv))×M as shown in No. 61g1, and in order to reduce the error, it is calculated by RAV and RBVC) 9d(J) + If we take the average, we get Here M is optical (
The rate is 8.

Regarding Qii) ψ, in Figure 7, the workpiece 1 is drawn horizontally and the sensor body is tilted. Further, in the figure, 18 is the top surface of the workpiece 1, 19 is the groove bottom position, and ds and D.

respectively indicate the distance from the intersection of the slit beams 15a and 15b to the groove 7+η bottom position 2 and the top surface of the workpiece 18.・d
A. dl; warping dll, dl
It shows the length of the hypotenuse of a given right-angled pentagon.

From Figure 7, ”’　A　　;(L　/l　cosψ.

n B 2d BCO3ψ5 dA=c1. (Lmψ,, ten tan (θ4−ψ, 9))
d, B=d, 9(fbn(θ, 1ψ,)−tanψ0)
dWA ” dA CO3ψ.

dVl"" (l BCO3ψS dZD, (tanψ, +15 (θ, -ψo)) cl knee〇, (tan (θ, +ψ, ) -tanψ,) is obtained.

Therefore, Gn, -d,. A), jr of (nB-dWn)
At 4t, the sign of ψ5 is determined.

Furthermore, if the same process is performed for mA shown in FIG.

Regarding Qvlα, let the half angle of the groove angle of the groove groove 2 be 07, and θ. , θ' is the tilt angle α relative to the ■ direction of the slit image in the image, nB '''B is the position of the light ray 15b to the slit 1 passing through the 11■ bottom position 19 [11 of the cut image 16b]
The distance from the lunar marker H1 at a point equidistant in the V direction of the cut @16b from the 11th curve point] is shown.

Let's say ■Nie■A here.

From a1gla, b, c・7", -rLWA=d%mnOtsu ("-Ml)rn
2 d w A: CL 2 tan OZ (
;M 2 )CL+ = ■7b / (迦(OK-
α))'h=V+1/ (t”n(ox+α))・,
M, = (V,,wJ7)/(tan ((It
, −α)) M 2 ” (■7, theory θi )/ (un
(Oy, +α)) Therefore, the inclination angle α is obtained.

Above, the cut image 16a of the two slit beams 15a and 15b
.

Did I explain that the correlation in 16b provides enough data to determine the posture of the workpiece 1 in total? Because of the intensity, it is necessary to separate the detection light from the arc light, and more preferably from the background light.

This separation of the detection light is performed as follows.

In pulse welding, that is, when welding with a pulsed welding current, the arc intensity also fluctuates in a pulsed manner, and the arc light is also not constant, resulting in a welding type 'IA'h pulse shape (this causes brightness and darkness).

Therefore, the detection light is only detected when the arc light is weak.

In FIG. 1, the imaging device 3 includes, from the objective side, a protective glass 20, a wavelength selection filter 21, an electronic shutter 22, a lens 23, a jM image element 24, etc., and the electronic shutter 22 applies a voltage. By doing so, it is possible to pass and block i3 excess light.

(most η element f-24, electronic shutter 22, light source 4a
, 4b are each connected to a control device 66 and are driven synchronously.

jl! The analog video signal 25 from the primary image 24 is inputted to the AD converter 8 via the filter 21, and is temporarily stored in the storage circuit 13 as a digital video signal 26.

The brightness of the area to be measured is detected by the light detector 5, and the detection result is sent to the timing generator 1 through the amplifier 9.
0 will be panono. A level setting signal for brightness is manually input to the timing generator IO in advance, and when the detected brightness reaches the set level L, a timing signal is issued to the increased sweetfish (J (Fig. 9)). Welding in Fig. 9: The reason why there is a deviation from the pulse J of IAL (also known as the timing signal) is that the brightness detected by the light detector 5 and the brightness of the arc 9 alone do not match due to the emission of heat. It shows.

The timing generator 10 operates the shutter drive circuit 12 so that a voltage is applied to the electronic shutter 22 when the brightness of the area to be measured is above a set level. That is, the imaging device 3
Detection light is taken in only when the arc light is dark. or,
The timing signal of the timing generator 10 is sent to the AD converter 8.
It is also panned over to the memory circuit 13 to clarify the detection timing of the stored signal, and performs signal processing in synchronization with a timing signal.

Note, the wavelength selection filter is intended to further improve the noise ratio of the detection signal, and if the light at the redundant point to be measured when capturing the detection light is dominated by the light emitted from the bead, the slit beam will be For example, use a blue color and use a blue wavelength selection filter.

As mentioned above, when the intensity of the arc light is weak, the strong influence of the arc light can be significantly reduced to 4 if the detection light is reduced to 1 (intensity), but the background light power still remains. In order to extract the detection light from this background light, a further operation is performed.

Light emission 6j'' at data intake 119JfJI (see Figure 9)
A4a.

If you blink 4b and image the cases with and without the detection light, you should be able to obtain a video fg in which the other parts except for the detection light part are almost identical, and both video signals By comparing the values, the detected light can be extracted separately from the background light.

III. The light emitting source drive circuit 11 performs timing generation x (
The timing signal from 10 causes the work 1 to be irradiated with a slit beam as shown in FIG.
Drive a and 4b.

Due to the flashing of the light emitting sources 4a and 4b, a central image signal B with detected light at approximately the same time is stored in the memory circuit 13 (No.
? A video signal 3 of the detected light which has been calculated by jIi and is separated from the background light is output.

■Do 1. The output signal 27 has an extremely good signal-to-noise ratio, and the accuracy on the layer side is improved.

Next, the light emitting sources 4a and 4b are driven to alternating current D:,
Image-4-Li 1jIi@ 16a and 16b are not imaged at the same time), and processing of liJ image signal is disconnected@]
, 6a, or 16b 10,000 times, then execute fg! When comparing the obtained f/J report, it is 1
With the ability to process the video signal of a cut image of a book, it is possible to process the video signal of two cut images, and the capacity of the storage circuit 13 and the capacity of the computer 14 can be reduced.

A case where the imaging device 3 shown in FIG. 1 is a television camera and the display device (not shown) is a video monitor will be described below.

An image on a video monitor is formed by a collection of many scanning lines, and several methods can be considered for capturing the image signal (video signal) 28.

An example is shown in FIG.

In the example shown in FIG. 10, the light emitting sources 4a+4b are switched every field (a group of signals where the running and batting line goes around the screen once), and video signals for the cut image 16a, the cut @ 16b, and the background light are captured. This is what I did. Cut image 16a,
16b, the timing at which the background light is captured is determined by separating the synchronization signal 29 included in the video signal using the synchronization signal separation circuit 3o shown in FIG.
By panoJ, the timing generator 1o emits light fA4a.

4b, by instructing the memory circuit 13 and the like.

In the example shown in the figure, the video signal 1i for one scanning line is
The light emitting sources 4a and 4b are switched to j, and the cut images 16a and 16b are
11 of the cut images 16a, 16b, ! This allows the processing to be completed in one field.

The signal C for one scanning line of the video fl'+υ (IH in the figure) contains the video signal 31 and the synchronization signal 18 and 32, and the video signal ρ
The signal import timing is based on this synchronization signal 32 according to the four rules fi.
The i-th n1 circuit 30 is used to shunt the signal, and the calculation is performed in the same manner as in the iσ statement.

Enlarged video fi3 It is already clear that the cut image 16a
, 16b are displayed as partial rows of scanning lines, and the peaks ((f4 or -) that appear in each scanning line are
, pi j1 is made smaller.

In the method shown in FIG. 11, one field is enough to transmit an image.

Incidentally, the irradiation direction of the slit light beam is not limited to the above-mentioned embodiments, but it is sufficient that the various data described in 1111 can be obtained from the correlation between the two cut images.

As described above, according to the present invention, (i) it can be used as a measurement sensor using the optical cutting method or as a sensor for a welding machine; (11) it can be used to measure workpieces that could not be measured using the conventional optical cutting method; 13ii) It is possible to obtain a video signal with a good noise ratio that is separated from arc light and background light, (Jψ (Jψ) be effective.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of the apparatus of the present invention, Fig. 2 is an explanatory diagram of the positioning of the cut image on the screen, Fig. 3 is a diagram showing the relationship between the slit beam and the workpiece, Figs. Figure 6 is a diagram showing the positional relationship of cut images on the screen, Figure 7 is a diagram showing the relationship of Surin [・rays to the workpiece, mB diagrams a, b, c
9 is an explanatory diagram showing the relationship of the slit beam to the workpiece and an image of the cut image, FIG. 9 is a basic timing chart of this apparatus, and FIGS. 1O and 11 are timing charts showing the timing of capturing the video signal. 1 is a workpiece to be welded, 4a and 4b are light emitting sources, 5 is a light detector, 6 is an m control device, 15a and 15b are slit beams, 16a and 16b are cutting images, 22 is an electronic shutter, 2
4 indicates (111 image elements. !11 Revised 1 head person) Kawashima Hari 1g Heavy Industries Co., Ltd. 1:'T Applicant 4;) Ceremony Omnipack Fig. 1 Fig. 3 Fig. 4 Fig. 5 Figure 6'j;*'170 Book 9

Claims (1)

[Claims] 1) A pair of light emitting sources that irradiate the workpiece with the slit-shaped beam described in 2, an imaging device equipped with an electronic shutter, a light detector that detects the brightness of the part to be measured, and a detection result of the detector that detects when the arc is dark. Ir1I The electronic shutter is opened, the light emitting source is blinked when the electronic shutter is opened, and the video signals of 9 cross-sectional images by the 2 slit beams are individually captured by the imaging device, and the correlation between the two cross-sectional images is determined by 1'1]. (+ffi) and the configured li!f control device.
Posture 51 of workpiece during pulse welding with i7J
Nail device.