KR20020019276A - Apparatus and method for measuring the width of the strip and method for correcting the measuring value - Google Patents

Abstract

PURPOSE: A device and method for measuring width of a strip is provided to automatically compensate an error without fixing pieces and to improve workability. CONSTITUTION: A device for measuring width of a strip comprises a moving wheel attached to a lower portion of a frame; a moving motor installed on the frame; a moving trunk unit moving on a rail; a lamp box(112) formed of light emitting diode(111) by being assembled in the moving trunk unit; a sensor protecting box(117) having inner and outer edge sensors(113,116) by being mounted on the lamp box; a transferring shaft(115) moving the lamp box left and right; a light source unit having a timing belt(119) and a limit sensor(118); a fixed piece supplying motor rotating a fixed piece; and a clock generator generating a CCD sensor driving signal into a CCD camera.

Description

Apparatus and method for measuring the width of the strip and method for correcting the measuring value}

The present invention relates to a width measuring device for measuring the width of a steel sheet, and a calibration method and a strip width measuring method for calibrating the same, and more particularly, the width of the strip while the light source is not fixed and automatically moves according to the width of the strip. And a strip width measuring device capable of accurately measuring the width of a strip by automatically correcting it in a short time when a measurement deviation occurs due to an abnormality of the measuring device, and a method of calibrating the same and a method of measuring a strip width.

In general, the apparatus for measuring the width of the cold rolled steel sheet strip, as shown in Figure 1, the length of the support (4) in the lower portion of the support (4) fixed perpendicular to the traveling direction of the cold rolled steel sheet strip (1) A special light source 2 is provided along the direction. At this time, when the strip 1 is advanced on the special light source 2, the portion of the light covered by the strip 1 is detected by the CCD camera 3 to measure the width of the strip.

As such, the strip width measuring apparatus has the following problems.

Since the method of measuring the width of the strip 1 measures the light exposed through both ends of the strip width (hereinafter referred to as 'edge'), even though a light source in the center portion where the light is blocked by the strip is unnecessary. Energy is wasted because a long fluorescent lamp (5; see FIG. 2) that emits light over the entire width of the strip is wasted energy. There is a problem that the price is expensive.

In addition, as shown in FIG. 1, the light source 2 is caused by the horizontal or vertical change of the support 4 and the foreign matter and dust, as well as the positional variation of the CCD camera 3, the voltage instability and the vibration during operation. Deterioration of the roughness is accompanied by measurement errors in the strip width.

However, such a width measuring device does not correct the measurement error during operation, but only adversely affects the product quality since the calibration operation of the measuring device is performed only during a specific period when the strip is not in progress such as a regular repair or a heavy repair.

On the other hand, also in the calibration work, as shown in Figure 2, because the manual calibration by a person using the calibration specimen mounting table 10 and a plurality of calibration specimens 11 takes a lot of time, work precision is reduced, etc. There is a problem.

SUMMARY OF THE INVENTION The present invention has been made to solve the conventional problems as described above, and it is possible to use a light emitting diode that is universally usable for a light source, has a small size, has a high illuminance, and is inexpensive. It can be quickly calibrated and provides a strip width measuring device that can be automatically calibrated during operation by calibrating remotely without the need for multiple calibration specimens and tools, and a method for calibrating it and measuring the strip width. There is a purpose.

1 is a perspective view of a strip width measuring apparatus according to a conventional embodiment.

Figure 2 is a block diagram showing a calibration method of the strip width measuring apparatus according to the prior embodiment.

Figure 3 is a perspective view showing the configuration of the strip width measuring apparatus according to the present invention.

Figure 4 is a perspective view showing the configuration of a variable position light source according to the invention.

Figure 5 is a block diagram showing a method for calibrating the width measuring device according to the present invention.

6 is a circuit diagram showing a configuration of a CCD camera according to the present invention.

7 is a flow chart for calibrating the width measuring device according to the present invention.

8 is a flowchart of a strip width measurement mode according to the present invention.

<Description of Symbols for Major Parts of Drawings>

1: strip 100: C type moving cart

100a, 100b: Frame 102: Moving wheel

103: moving motor 104: rail

110a, 110b: variable position light source 112a, 112b: lamp box

113: first edge detection sensor 116: second edge detection sensor

117: sensor protection box 121a, 121b: movable specimen member

124: fixed specimen member 130: control device

140: computer unit 141: central processing unit

In order to achieve the above object, according to the present invention, the CCD camera detects the light emitted from the light source located in the lower portion of the steel sheet strip to measure the width of the steel sheet strip at least two light sources at a predetermined interval A lower frame spaced apart from each other and at least two CCD cameras for detecting light emitted from the light source, the upper frame spaced apart at predetermined intervals, and a C-type movable trolley which is movable in the transverse direction of the strip direction; And a fixed specimen member having a predetermined area positioned at a central portion of the lower frame, and two movable specimen members positioned at both sides of the fixed specimen member and movable along the longitudinal direction of the lower frame. And a lamp box incorporating two light emitting diodes, wherein the light source is Characterized in that is movable along a two-way.

According to another embodiment of the present invention, a calibration method of a strip width measuring apparatus includes positioning the movable test piece member at a predetermined point on the lower frame, and the edge of the fixed test piece member is connected to the first edge detection sensor of the lamp box. Adjusting the position of each of the lamp boxes so as to be positioned between the second edge detection sensors, counting pixel numbers of CCD sensors corresponding to the edges of the fixed specimen members, and corresponding edges of the movable specimen members. Counting pixel numbers of the CCD sensor, and calculating reference distances Sa and Sb of each of the movable specimen members by Equations 1 and 2,

<Equation 1>

Sa = Ba (mm) / [7Da-7Ca],

<Equation 2>

Sb = Bb (mm) / [7Db-7Cb],

Here, Ba and Bb is the distance from the edge of the fixed specimen member to the edge of the movable specimen member, 7Da and 7Db is the pixel number of the CCD sensor corresponding to the edge of the movable specimen member, 7Ca and 7Cb is the fixed Characterized in that the pixel number of the CCD sensor corresponding to the edge of the specimen member.

According to another embodiment of the present invention, the strip width measuring method comprises the steps of moving the C-type moving trolley to the measurement position, the edge of the strip is located between the first edge detection sensor and the second edge detection sensor Comprising each step of moving the lamp box, and calculating the width of the strip by the following equation (3),

<Equation 3>

Here, Sa and Sb are reference distances, 7Ea and 7Eb are pixel numbers of the CCD sensor corresponding to the edge of the strip, Ca and Cb are pixel numbers of the CCD sensor corresponding to the edge of the fixed specimen member, and A is fixed. It is characterized in that the width of the specimen member.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

Strip width measuring apparatus according to an embodiment of the present invention is a moving trolley portion 100 having a structure capable of moving the CCD camera and the structure to the calibration position, and the variable light source unit 110 that automatically changes the position of the light source according to the width of the strip And, the calibration specimen portion 120 to move the specimen as needed; A control unit 130 for controlling each element and automatically measuring width and performing calibration according to CCD camera data and equations; Comprising a computer 140 for processing the calibration and measurement results in accordance with the program.

Referring to FIG. 3, the frame 101 of the mobile trolley portion 100 is a C-shaped frame that firmly supports the CCD camera 3 in the upper portion and the respective components in the lower portion. 102 and the moving motor 103 is configured to be able to move on the rail (104).

Referring to FIG. 4, a plurality of light emitting diodes 111 are embedded in the lamp box 112 of the variable light source unit 110 to emit light toward the upper portion thereof, and the inner edge detection sensor 113 and the outer edge portion thereof are disposed on the upper portion thereof. The sensor protection box 117 attached with the detection sensor 116 is coupled to one side, and a rod-shaped feed shaft 115 penetrates the side of the lamp box 112 so that a plurality of the lamp sensors 112 are assembled in parallel. The entire of may be moved according to the guidance of the feed shaft (115).

In addition, the timing belt 119 connects the ramp box 112 and the transfer motor 114 to form a structure in which the ramp box 112 moves when the transfer motor 114 rotates. Limit sensor 118 is attached to limit the transfer distance of the lamp box (112).

The calibration specimens of the calibration specimens 120a and 120b are manufactured in a constant size and are fixed to the axis of the calibration specimen supply motor by the specimen clamp, and the calibration specimen supply motor is calibrated according to the instructions of the computer 140. It is configured to allow 180 degrees of displacement of the specimen to the left or to the right. On the other hand, the central calibration specimen 124 is manufactured to an appropriate standard and installed in the center of the instrument.

3 and 6, the control unit 130 generates a master clock signal 150 and supplies the clock generator 131 to the CCD camera 3, and a video signal received from the CCD camera 3. An analog signal processing card 132 for converting the 152 into a pulse signal, and a pixel count circuit card 133 for counting and transmitting the pixel 153 of the CCD camera 3 to the computer 140. .

The computer unit 140 uses the data transmitted from the control unit 130 and a width W of the strip and a reference distance S indicated by 1 pixel according to a preset equation (hereinafter, referred to as 'reference distance'). And a central processing unit 141 for controlling the moving motor 103 of the moving cart 100 and the transfer motor 114 of the variable light source 110.

Hereinafter, the operation of the present invention will be described with reference to FIGS. 5 and 7.

First, before measuring the width of the strip 1, the remote computer 140 is turned on to execute the normalization mode program (step 1101). After that, the calibration specimen supply motor of the calibration specimen portions 120a and 120b is operated to set the calibration specimens 121a and 120b to the correct positions (step 1102).

At this time, the transfer motors 114a and 114b of the variable light source units 110a and 110b are operated to move the lamp boxes 112a and 112b toward the central calibration specimen 124, respectively (step 1103). When the lamp boxes 112a and 112b contact the limit sensors 118a and 118b, the transfer motors 114a and 114b stop and the middle portion of the lamp boxes 112a and 112b is the edge portion of the center calibration specimen 124. Ca, Cb).

When the CCD cameras 3a and 3b are turned on, the pixels 7a and 7b of the CCD sensors 6a and 6b react, and the pixel count circuit card 133 of the control unit 130 controls the central calibration specimen ( The number of pixels 7Ca and 7Cb corresponding to the edges Ca and Cb of step 124 is counted (step 1104). Thereafter, the transfer motors 114a and 114b of the variable light source units 110a and 110b operate to move the lamp boxes 112a and 112b toward the calibration specimens 121a and 121b, respectively (step 1105).

When the condition that the outer edge detection sensor 116 is turned ON and the inner edge detection sensor 113 is satisfied is satisfied, the transfer motors 114a and 114b are stopped, and the middle portion of the ramp boxes 112a and 112b is the calibration specimen 121a, The edges Da and Db of 121b are respectively positioned. At this time, the pixels 7a and 7b of each of the CCD sensors 6A and 6B react, and the pixel count circuit card 133 of the control unit 130 causes the edge portions Da and Db of the calibration specimens 121a and 121b to operate. ), Pixel numbers 7Da and 7Db corresponding to &lt; RTI ID = 0.0 &gt;

The pixel count circuit card 133 transmits the counted pixel numbers 7Ca, 7Cb, 7Da, and 7Db to the computer 140, and the computer 140 transmits 1 by the following equations 1 and 2 based on the received signals. The reference distance S corresponding to the pixel is calculated (corresponding to 1107 in FIG. 11).

[Equation 1]

Sa = Ba (mm) / 7Da-7Ca (mm),

Here, Sa is the reference distance of the a-side CCD camera 3a, Ba is the distance from the point Ca to the point Da in FIG. 5, and 7Da is the number of the pixel 7 of the CCD sensor 6 corresponding to the point Da. And 7Ca is the number of the pixel 7 of the CCD sensor 6 corresponding to the point Ca.

[Equation 2]

Sb = Bb (mm) / 7Db-7Cb (mm),

Here, Sb is the reference distance of the b-side CCD camera 3b, Bb is the distance from the point Cb to the point Db in FIG. 5, and 7Db is the number of the pixel 7 of the CCD sensor 6 corresponding to the point Db. 7Cb is the number of the pixel 7 of the CCD sensor 6 corresponding to the point Cb.

The calculated reference distances Sa and Sb are stored in the memory of the computer 140 as a reference for measuring the width of the strip 1 (corresponding to 1108 in FIG. 11).

When the calibration is completed according to the above sequence, to reset the calibration specimen 121 to the original position to measure the width of the strip (1). When the width measurement mode is executed in the program of the computer 140 as shown in FIG. 8, the moving motor 103 of the moving cart 100 causes the C-type frame 101 to move to the width measurement position (see FIG. 12). Equivalent to 1201). The transfer motor 114 of the variable light source unit 110 is operated by a program so that the lamp box 112 is moved in the edge directions Ea and Eb of the strip 1 and the outer edge detection sensor 116 is turned on. ), The transfer motor 114 is turned off to stop the lamp box 112 (corresponding to 1202 in FIG. 12).

If the inner edge detection sensor 113 is turned on because the width of the strip 1 decreases, the transfer motor 114 is operated so that the lamp box 112 is turned off when the inner edge detection sensor 113 is turned off. By moving inward, the edges Ea and Eb of the strip 1 are automatically controlled so that they always exist between the outer edge detection sensor 116 and the inner edge detection sensor 113 (corresponding to 1203 of FIG. 12). ).

At this time, the CCD camera 3 operates to recognize the edges Ea and Eb of the strip 1, transmit the corresponding pixel 7Ea and 7Eb numbers, and count them in the pixel count circuit card 133 ( Corresponding to 1204 in FIG. 12).

The pixel count circuit card 133 transmits the counted pixel numbers 7Ea and 7Eb to the computer 140, and the computer 140 uses the a-side CCD camera (3) based on the received signals. The width of the strip 1 measured by 3a) and the b-side CCD camera 3b is calculated (corresponding to 1205 in Fig. 12).

[Equation 3]

Wa = [(Sa X (7Ea-Ca)] + A / 2 (mm),

Here, Wa is one width of the measured strip 1 of the a-side CCD camera 3a, Sa is derived from Equation 1 above, and 7Ea is a CCD corresponding to the edge Ea of the strip 1. The number of pixels 7 of the sensor 6, A is the width of the center calibration specimen 124.

[Equation 4]

Wb = [Sb X (7Eb-Cb)] + A / 2 (mm),

Here, Wb is one width of the measured strip 1 of the b-side CCD camera 3b, Sb is derived from Equation 2 above, and 7Eb is a CCD corresponding to the edge Eb of the strip 1. The number of pixels 7 of the sensor 6, A is the width of the center calibration specimen 124.

The calculated value is calculated by the following Equation 5 to measure the total width W of the strip 1 continuously.

[Equation 5]

W = Wa + Wb (mm).

According to the result of the above calculation formula, the computer 140 displays the measured width W of the strip 1 on the screen.

In summary, in the apparatus for measuring the width of the strip using a CCD camera, the moving wheel 102 and the moving motor 103 are attached to the lower portion of the C-shaped frame 101 having one side open, and the rail 104 is attached. A mobile loan portion 100 that is movable on the; The lamp box 112, which is assembled in the movable balance unit 100 and is formed of a light emitting diode 111, and has an inner edge detection sensor 113 and an outer edge detection sensor 116 attached thereto, on the lamp box 112. A variable light source unit including a sensor protection box 117 to be assembled, a transfer shaft 115 and a transfer motor 114, a timing belt 119, and a limit sensor 118 for transferring the lamp box 112 from side to side. 110; The central calibration specimen 124, which is assembled in the moving trolley portion 100 and installed at the center of the calibration specimen supply motor 122 and the two calibration specimens 121a and 121b, which rotate the position of the calibration specimen 121 by 180 degrees. Calibration specimen portion 120 composed of; A clock generator 131 which periodically generates a master clock signal and a CCD sensor driving signal to the CCD camera 3, and the pixel 7 number of the CCD sensor 6 using data from the analog signal processing card 132; A control unit 130 for counting and transmitting the result to the computer 140; Central processing for calculating the width (W) and the reference distance (S) of the strip (1) according to a previously set equation using the data transmitted from the control unit 130 and controlling each component according to the program And a computer unit 140 including the device 141.

As described above, according to the present invention, there is a special effect that the measurement accuracy is high and the work efficiency is improved by automatically performing the calibration of the width measuring device during the online operation by using a light source of low cost and small size.

Claims (7)

In the device for measuring the width of the progressive steel strip by the CCD camera detects the light emitted from the light source located in the lower portion of the progressive steel strip, A lower frame having at least two light sources spaced at a predetermined interval, and an upper frame having at least two CCD cameras for detecting light emitted from the light source being spaced at a predetermined interval in a transverse direction of the traveling direction of the strip; A movable type C moving cart, A fixed specimen member having a predetermined area positioned at the center of the lower frame; Two movable specimen members positioned on both sides of the fixed specimen member and movable along the longitudinal direction of the lower frame; The light source is provided with a lamp box in which a plurality of light emitting diodes are built, the light source is strip width measuring apparatus characterized in that movable in the longitudinal direction of the lower frame. The method of claim 1, The lamp box is a strip width measuring device, characterized in that the sensor protection box is provided with a first edge detection sensor and a second edge detection sensor mounted on one side. The method of claim 2, The lamp box is a strip width measuring device, characterized in that the position change on the lower frame so that the edge of the sheet steel strip is located between the first edge detection sensor and the second edge detection sensor. The method of claim 3, The movable specimen member is capable of selectively blocking the light source, so that the strip width measuring device is removed from the upper portion of the light source when measuring the width of the strip of traveling steel sheet. The method of claim 3, A clock generator for periodically generating a master clock signal and a CCD sensor driving signal to the CCD camera, a control unit for counting and storing pixel numbers of the CCD sensor using data from an analog signal processing card; And a computer unit for calculating a width and a reference distance of the strip according to a preset equation using data transmitted from the control unit. In the method for calibrating the strip width measuring device having the configuration of claim 1, Positioning the movable specimen member at a predetermined point on the lower frame; Adjusting the position of each of the lamp boxes such that the edge of the fixed specimen member is located between the first and second edge detection sensors of the lamp box; Counting a pixel number of a CCD sensor corresponding to an edge of the fixed specimen member; Counting a pixel number of a CCD sensor corresponding to an edge of the movable specimen member; Equations 1 and 2, <Equation 1> Sa = Ba (mm) / [7Da-7Ca], <Equation 2> Sb = Bb (mm) / [7Db-7Cb], Comprising the step of calculating the reference distance (Sa, Sb) of each of the movable specimen member, Here, Ba and Bb is the distance from the edge of the fixed specimen member to the edge of the movable specimen member, 7Da and 7Db is the pixel number of the CCD sensor corresponding to the edge of the movable specimen member, 7Ca and 7Cb is the fixed And a pixel number of the CCD sensor corresponding to the edge of the specimen member. In the measuring method of the strip width measuring apparatus calibrated by the structure of claim 6, Moving the C-type moving cart to the measurement position; Moving the lamp boxes so that the edges of the strip are located between the first and second edge detection sensors; Equation 3 <Equation 3> By calculating the width of the strip by Here, Sa and Sb are reference distances, 7Ea and 7Eb are pixel numbers of the CCD sensor corresponding to the edge of the strip, Ca and Cb are pixel numbers of the CCD sensor corresponding to the edge of the fixed specimen member, and A is fixed. Strip width measuring method, characterized in that the width of the specimen member.