JPH11281329A - Apparatus for measuring length of long object - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable measurement of the effective length of a long object by switching a plurality of cameras to display photographed pictures on a monitor, moving cursors and measuring, based on the pictures shown by the cameras which takes in both ends of the long object. SOLUTION: A long object 1 moving in the axial direction of a length measuring line is stopped temporarily, photographed by a plurality of cameras 21 -2n disposed along the length measuring line to display photographed pictures on a monitor 6 through a camera switch controller 3, and a measuring person operates the camera switch controller 3 with observing the monitor 6 to extract two cameras which take one and other ends of the long object 1, visually observes the displayed pictures to specify the effective width between both ends of the long body 1, and sets a cursor 6a to the effective width. Thus the distances between the two cameras centers and effective width, i.e., the effective lengths of both ends are obtd. and the distance between the two cameras is added thereto to obtain the total effective length of the long body 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is suitable for use in measuring the effective length of a long object such as a steel pipe or a steel bar, particularly, a high-temperature steel pipe extruded by a hot extrusion tube press. The present invention relates to a length measuring device for a long object.

[0002]

2. Description of the Related Art A steel pipe in a high temperature state while being extruded by a hot extrusion tube press is deformed in a spear shape at a top end of the extruded steel pipe, and this deformed portion does not become a product. Therefore, the extruded steel pipe is sent to the next step after its deformed portion is cut and removed by the hot cutting device.

However, the length of the deformed portion is not constant for each steel pipe. Therefore, for each steel pipe, the length of the deformed portion, in other words, the effective length of the steel pipe, is measured before cutting and removing the deformed portion.

Conventionally, the following length measuring device has been used for measuring the effective length of the steel pipe.

FIG. 2 is a schematic block diagram showing the configuration of a conventional length measuring device. In the figure, a long object to be measured, specifically, a steel pipe 1 in a high temperature state is sent along a length measuring line composed of, for example, a skew roller conveyor in the axial direction thereof and temporarily stopped.

[0006] Beside or above the length measuring line,
CCD image sensor or an image dissector multiple cameras 2 ₁ to 2 _n made of is not found superimposed imaging range is secured in tandem at a predetermined interval.

The plurality of cameras 2 ₁ to 2 _n are sequentially switched by the camera switching control means 3, and photograph the long object 1 which has been sent on the length measuring line and stopped temporarily, and the photographing thereof is performed. The image is output to the image processing means 4.

The image processing means 4 binarizes an image taken by each camera in units of pixels based on a predetermined threshold of a predetermined luminous intensity, and sets the number of pixels indicating a luminous intensity equal to or larger than the threshold in the width direction of the long object 1 Differentiate the distribution curve obtained by summing
It is determined that the position where the differential value is equal to or larger than a predetermined threshold value is the pipe end, and the result of this determination is output to the calculating means 5.

Then, the arithmetic means 5 to which the image processing result is input is provided with two camera numbers (in the illustrated example, two camera numbers) capturing the extruded top end and bottom end of the steel tube 1. ₃ and 2 _n-1 ), the distance L _M between the two cameras, which is the default value, and the camera center 2 c (see FIG. 3 described later), which is the image processing result of the images captured by these two cameras. spaced to the top side pipe end 1 _T distance L _T (illustrated example "+") and the distance to the bottom tube end 1 _B L _B (illustrated example "+") length is determined based on the L
Is calculated as the total effective length of the steel pipe 1.

However, the conventional length measuring device using the image processing means 4 cannot not only accurately measure the effective length of the steel pipe 1 when the wall thickness of the steel pipe 1 is extremely thin, but also causes a transportation trouble, If it is significant, the measurement becomes impossible, and there is a problem that the length measurement operation by hand using a tape measure or the like is forced. This is for the following reason.

That is, in the above-described conventional length measuring device, as described above, the distribution curve of the number of pixels in the width direction of the long object 1 having a luminous intensity equal to or greater than the threshold value preset by the image processing means 4 is obtained. It is determined that the position where the differential value is equal to or larger than the predetermined threshold is the pipe end.

Therefore, taking as an example a camera that captures the end of the tube on the extrusion top side, the image processing result when the temperature of the steel tube 1 is sufficiently high, as shown in FIG. true effective length L _T of the distal end portion excluding the portion only deformation is detected.

However, if the thickness of the steel pipe 1 is thin or a transport trouble occurs, the temperature of the steel pipe 1 drops, especially at both ends, so that the image processing result in this case is shown in FIG. as shown in b), it is determined should △ L _T moiety is originally valid portion and ineffectiveness is due to the effective length L _TM incorrect tip is detected.

Further, the measurement itself becomes impossible because the steel pipe 1
This is because, when the temperature drop is extremely extreme, the image processing result of the image captured by all the cameras indicates the absence of the effective portion of the steel pipe.

As an apparatus for measuring a long object using a camera, a movable trolley with a camera is arranged beside a long object to be measured, and one end of the long object is placed on a monitor. After aligning with the baseline, move the camera-equipped cart to align the other end of the long object with the baseline on the monitor, and measure the length of the long object by calculating the moving distance of the camera-equipped cart. (See Japanese Patent Application Laid-Open No. 6-347222).

However, the apparatus disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 6-347222 is extremely poor in measurement accuracy because mechanical play occurs in a camera-mounted cart due to wear of wheels and the like. In addition, it takes time to move the cart with camera,
It has a disadvantage that the measurement efficiency is extremely low, so that it cannot be used for measuring the effective length of the steel pipe.

[0017]

SUMMARY OF THE INVENTION The object of the present invention is not only to determine the thickness, but also to prevent the occurrence of transport troubles.
An object of the present invention is to provide a length measuring device for a long object capable of accurately and efficiently measuring the effective length of a steel pipe to be measured.

[0018]

Means for Solving the Problems The present inventor has made various studies to achieve the above object. As a result, in place of image processing, the image captured by the camera is displayed on a monitor having a movable cursor, and when the displayed image is visually checked by a measurer, the effective portion of the steel pipe is not affected by the temperature. The present invention has been accomplished by paying particular attention to the fact that the effective ends of both pipe ends can be accurately identified.

The gist of the present invention resides in the following length measuring device for a long object.

[0020] and a plurality of cameras 2 ₁ to 2 _n, which is fixedly arranged in tandem overlapping et when shooting range entire length of the long object 1 along the measurement line, as can image, a cursor for alignment A monitor 3 on which a monitor 3a is displayed, camera switching control means 4 for switching the plurality of cameras to display the captured image on the monitor, cursor operating means 5 for moving a cursor displayed on the monitor, and a long object of the camera captured, whereas the effective end of the elongate object relative to the camera center is measured based on two cameras in a monitor display image that captures the end and the other end P _T, the distance L _T of P _B ,
Measuring device elongated object, characterized in that by adding L _B to the distance L _M between the two cameras; and a calculating means 6 for determining the effective length L of the elongated object.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, a long object which has been sent in the axial direction on a length measuring line and has been temporarily stopped is overlapped with a photographing range along the length measuring line. Images are taken with a plurality of cameras fixedly arranged in tandem and connected to the monitor via the camera switching control means, and the taken images are displayed on the monitor.

At this time, the measurer operates the camera switching control means while looking at the monitor to extract two cameras capturing one end and the other end of the long object. Then, the monitor display images captured by these two cameras are visually observed to identify the effective ends of both ends of the long object, and the cursor (vertical line) previously displayed on the monitor is aligned with the effective ends.

By the above operation, the distance between the center of the two cameras and the effective end, that is, the effective length of both ends is measured, and the effective lengths of both ends are known values of the two cameras. By adding to the separation distance, the total effective length of the long object is obtained.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be specifically described with reference to the drawings showing the embodiments. FIG. 1 is a schematic block diagram showing a configuration of a length measuring device according to the present invention.

In the figure, a long object to be measured, specifically a steel pipe 1 in a high temperature state, is sent in an axial direction on a length measuring line composed of, for example, a skew roller conveyor, and temporarily stopped. You.

On the side or above the length measuring line,
CCD image sensor or an image dissector multiple cameras 2 ₁ to 2 _n made of is not found superimposed imaging range is secured in tandem at a predetermined interval.

The plurality of cameras 2 ₁ to 2 _n are sequentially switched by the camera switching control means 3 to photograph the long object 1 which has been sent along the length measuring line and has stopped moving temporarily, and the photographing thereof is performed. The image is output to the monitor 6.

The above-mentioned camera switching control means 3 outputs the number information of two cameras which have captured one end and the other end of the cameras which have captured the long object 1 to the arithmetic means 5 which will be described later. I can do it.

The monitor 6 has a cursor operating means 7
, A cursor 6a for positioning that is movable in the left-right direction in the monitor 6 is displayed.

The above-mentioned cursor operating means 7 includes a cursor 6
a, specifically, the distance on the monitor 6 from the camera center 2c of the two cameras capturing one end and the other end of the long object 1 (in the illustrated example, _LT and in L _B,
In each case, “+” is output to the calculating means 5.

The arithmetic means 5 described above, two cameras that capture the opposite ends of the long object 1 (in the illustrated example, 2 ₃ and 2 _n-1)
Of (in the illustrated example, L _M) distance is known values, the two distance L _B and L _T in terms of actual dimensions, the total effective length L of the formula "L = L long object 1 _M + (L _T + L
_B )).

The distance between the cameras is stored in advance in the arithmetic means 5, and the number information of the two cameras capturing one end and the other end of the long object 1 is stored. on the basis and obtains the L _M in the above formula.

The length measuring device of the present invention configured as described above is used in the following procedure.

First, the steel pipe 1 in a high temperature state in which only the extrusion top side, which is sent on the length measuring line in the axial direction, is deformed into a spear shape is temporarily stopped. In this state, the measurer operates the camera switching control means 3 to select one of the plurality of cameras, which seems to be capturing the end of the steel pipe 1 on the extrusion top side, The captured image is displayed on the monitor 6.

Next, the measuring person observes the photographed image displayed on the monitor 6 and, when confirming the self-luminous image of the steel tube 1 including the extruded top tube end, visually observes the displayed image in detail. to both identify identify valid edge 1 _T top side Hover 6a enable end 1 _T was identified identified by operating the cursor operation means 7.

[0036] By the above operation, the effective length L _T on the monitor 6 of the extruded top side of the steel pipe 1 is measured, the value is input to the arithmetic unit 5. At the same time, the camera number 2 _n-1 is input to the calculating means 5.

During the above operation, if the self-luminous image of the steel pipe 1 is not observed in the monitor 6, the camera switching control means 3
To sequentially display the captured images of the camera on the right side (closer to the bottom) of the selected camera on the monitor 6, and search for a self-luminous image of the steel pipe 1 including the extruded top end.

Conversely, when the self-luminous image of the steel pipe 1 is observed over the entire width of the monitor 6, the camera switching control means 3 is operated to operate the camera switching control means 3 on the left side (closer to the top) as described above. The images captured by the camera are sequentially displayed on the monitor 6, and a self-luminous image of the steel pipe 1 including the extruded top end is searched for.

Further, the extrusion is self-luminous image of a steel pipe 1 comprising the top side of the pipe end is observed, when the photographing posture is poor identify identify valid edge 1 _T of the difficulty is, measurement line Start the skew roller conveyor that constitutes
Is preferably moved slightly and rotated about the axis so as to obtain a captured image in a posture shown as “top monitor image” in the figure.

[0040] After the cursor 6a adjustment is finished to the effective end 1 _T was identified particular above extrusion top side,
By operating the camera switching control means 3, the image taken by the camera on the right side (closer to the bottom) than the selected camera is displayed on the monitor 6.
And the steel pipe 1 including the extruded bottom end
Search for a self-luminous image of.

[0041] Then, the target display image self-luminous image of a steel pipe 1 comprising the pipe end of the extrusion bottom is confirmed, both to identify the specific active end 1 _B of the bottom side and detail visually observed, cursor operation Hover 6a enable end 1 _B was identified identified by operating the means 7.

[0042] By the above operation, the effective length L _B on the monitor 6 of the extruded bottom of the steel pipe 1 is measured, the value is input to the arithmetic unit 5. In parallel with this to enter the number 2 ₃ of the camera to the computing means 5.

The effective length of the effective length L _T and the bottom side of the top side of the monitor 6, which is measured as described above L _B, and the two camera number 2 _n-1 and 2 ₃ is input calculating means 5 is configured to convert the L _T and L _B to the real dimensions, in terms of the distance L _M between the camera obtained based two cameras number 2 _n-1 and 2 _3, the above formula "L = L _M + (L _T
+ L _B ) ”to calculate the total effective length L of the steel pipe 1.

[0044]

According to the present invention, out of a plurality of cameras, a measurement person visually observes monitor display images of two cameras capturing both ends of a long object including a deformed portion that does not become a product. Since the effective end is identified and the cursor displayed in advance on the monitor is set to the effective end, the true effective length of the long object can be accurately measured.

Further, the identification of the effective end can be performed irrespective of the temperature of the long object, and the length can be measured for all the long objects transmitted on the length measuring line.
The length measurement work using a tape measure by the measurement staff is not required, and the length measurement work efficiency is improved.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram showing a configuration of a length measuring device according to the present invention.

FIG. 2 is a schematic block diagram showing a configuration of a conventional length measuring device.

FIG. 3 shows an image processing result in a conventional length measuring device,
FIG. 7A is a schematic diagram when the temperature of the long object is sufficiently high, and FIG. 7B is a schematic diagram when the temperature of the end of the long object is low.

[Explanation of symbols]

1: long object (steel pipe), 1 _T : top effective end, 1 _B : bottom effective end, 2: camera, 2c: camera center, 3: camera switching control means 4: image processing means, 5: Calculation means, 6: monitor, 6a: cursor, 7: cursor operation means.

Claims (1)

[Claims] 1. A plurality of cameras (2 ₁ to 2 _n ) fixedly arranged in tandem with overlapping photographing ranges along a length measuring line so that the entire length of a long object (1) can be photographed. , Monitor (6) displaying cursor (6a) for positioning
Camera switching control means (3) for switching the plurality of cameras to display the captured image on a monitor, cursor operating means (7) for moving a cursor displayed on the monitor, and a long object. The distance between the effective end (1 _T , 1 _B ) of the long object with respect to the center of the camera measured based on the monitor display images of the two cameras capturing one end and the other end of the camera (1 _T , 1 _B ) L _T, characterized by comprising the L _B) and the distance between the two cameras (the L _M) in addition to the total effective length of the elongated object (L) calculation means for calculating (5) A measuring device for long objects.