JPS59188507A - Measuring method of amount of curvature of long-sized material - Google Patents

Abstract

PURPOSE:To detect the amount of curvature of a long-sized material automatically and accurately by projecting slit light at right angles to the lengthwise direction of the long-sized material and shotting its reflected image by an image pickup device, and calculating the amount of displacement from the fixed position of the reflected image due to the relative movement of the long-sized material. CONSTITUTION:The slit light is projected upon the long-sized material 1a on a mount 8 from a projector 2 at right angles to the lengthwise direction of the material, and its reflected image is shot by an image pickup camera 3. The projector 2 and camera 3 are moved along the long-sized material 1a together with a carriage 4. If the long-sized material 1a is curved, the crescent reflected image is displaced by Yi like a crescent image 14 shown by an alternate long and two short dashes line according to the extent Xi of the movement. The amount of curvature of the long-sized material 1a is detected automatically and accurately by the extent of the displacement from the fixed position.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for measuring the amount of bending of a long material, and more specifically, by moving a long material such as a round bar or shaped steel in its longitudinal direction, and measuring the amount of bending by optical means. This relates to a detection method that allows automatic detection.

Until now, there has been no suitable device to automatically detect bends in long materials such as round bars, shaped steel, pipes, etc., and workers generally measure the bends visually by directly applying measuring instruments. There is. However, visual inspection has large individual differences and is extremely inefficient.

From this point of view, for example, a measurement method as described in Japanese Patent Laid-Open No. 55-47406 has been proposed, but the measurement is complicated and improvements are desired.

That is, in this measurement method, a long material is transported in a direction perpendicular to its longitudinal direction, and during the transportation, measurements are taken from two directions, respectively, at both ends of the long material and at multiple positions between these two ends. At the same time as applying a light beam, detecting the reflected light, 2
The amount of bending of the long material is determined by detecting the distance from each measurement point in one direction. However, there are many measurement points in this direction, and the light beam may be supported from two directions.
Measuring devices and measurements themselves become more complex.

The present invention aims to solve the above-mentioned drawbacks, and specifically proposes a detection method that can automatically and accurately detect the amount of bending of a long material by irradiating it with a slit beam or a laser beam.

That is, the method of the present invention irradiates the surface of a long material such as a round bar or shaped steel with a slit beam or laser beam from a projector at right angles to its longitudinal direction, and captures the reflected image of the irradiated beam with an imaging camera. , when either the projector or the long material moves one of them relatively, the amount of deviation of the reflected image from the fixed position is determined by the imaging camera, and the amount of bending of the long material is calculated by combining the amount of deviation and the moving distance. It is characterized by being determined by calculation.

Hereinafter, the method of the present invention will be explained in detail with reference to the drawings.

First, FIG. 1 is a layout diagram of an example of an apparatus for carrying out the method of the present invention, in which reference numeral 1 indicates an underframe, and a stand 8 is provided inside the underframe 1. , a long material 1a such as a round bar is placed on the underframe 1 so that a projector 2 and an imaging camera 3 can move in parallel to the long material 1a. That is, the upper surface of the underframe 1 is used as a track, and the movable trolley 4 is movably disposed via wheels 6, and the motor 5 is driven during the movement. A floodlight 2 is attached to the lower part of the movable trolley 4 so that slit light or laser light can be projected vertically from the floodlight 2, and an Oka image camera 3 is mounted on the forward side at a distance from the floodlight 2 at the bottom of the movable trolley 4. The imaging camera 3 is configured to be able to capture a reflected image of a projected light beam such as a slit light beam.

Therefore, in the measuring device with the above configuration, a long material such as a round bar 1
When measuring the bending of a, after placing the long material 1a on the table 8, shine a slit-shaped light beam from the projector 2 onto the surface of the long material 1a at right angles to its longitudinal direction, and measure the reflection caused by the projection. The image is captured by an imaging camera 3 installed diagonally above the direction of movement. Viewed in this way, as shown in FIG. 3, in the case of a round bar, a half-moon-shaped image of the light beam is transmitted to the image receptor 12 of the camera 3. In this case, instead of projecting a slit beam, a laser point beam can be waved at high speed by a mirror and projected, or a straight laser beam created using a lens can be projected. While receiving the half-moon-shaped image of the light beam, the projector 2 moves along with the movable trolley 4.
The camera 3 is also moved along the elongated material 1a in the direction of the arrow in FIG. During this movement, if there is no bend in the long material 1a, the half-moon image 13 is at a fixed position in the center of the screen, but if there is a bend, it shifts upward, downward, leftward, or upward, as shown by the half-moon image 14 indicated by the two-dot chain line.

Therefore, as shown in the half-moon image 14 indicated by the two-dot chain line, there is a shift in either the up, down, left or right direction, the amount of shift (knee, 1.') is determined, and these amounts of shift are put into a computer, for example, and calculated as follows. The amount of bending can be determined.

In FIG. 1, if only the round bar or fang shifts, an apparent shift of 1.- will occur in the camera image.

If the camera is tilted by oto with respect to the vertical, '31 can be found from the relationship 1=disturbance.

Generally speaking, as shown in FIG. 5, there are two ways to determine the amount of bending: one is to calculate the absolute amount of bending per round bar 1a at 11, and the other is to calculate the bending gradient It/Zi.

Therefore, if you want to obtain the curve and the absolute amount 11 as in the former case, input the deviation amount (:cI, t+) to the square circuit of the calculator, and (5) l! It is determined by calculating the formula =W.

In addition, when determining the bending gradient as in the latter case, the movement amount 11 of the projector 2 is obtained from an odometer (not shown), and the value of the absolute bending amount 11 obtained as described above is used.
IH/zi=! It can be found by calculating the formula.

Further, a long material such as a round bar does not necessarily bend only in one direction; for example, when placed on a floor, it may bend in the left-right direction or in the vertical direction at the same level as the floor. However, in either direction, the amount of bending can be determined by rotating the round bar as described above.

Furthermore, when detecting the moving distance of the projector or the movable trolley, a travel position detection device can be attached to the movable trolley 6 for measurement.

Further, if the moving frame 7 of the elongated material and the underframe 1 are not parallel, the regular image 13 moves in either direction at a constant speed. If the amount of movement and displacement of the mobile cart 4 do not change linearly, as shown by the curve (a) in Fig. 4, and a deviation (σ) occurs with respect to the straight line (b), (6) this is a curve. The amount of bending can be measured from this point.

Note that FIG. 2 is a layout diagram of another device for carrying out the method of the present invention, and in the case shown in FIG. 2, the projector 2 and the imaging camera 3 are fixed to the pedestal 9, contrary to the case shown in FIG. The elongated material 1a is placed on a movable cart 10 supported by wheels 11, so that the elongated material 1a is movable. This device also measures in the same way as above.

As explained in detail above, according to the present invention, it is possible to automate and speed up the measurement of the amount of bending of a large number of long materials, and it is also possible to incorporate bending measurement into the production line. It can greatly contribute to efficiency in manufacturing.

[Brief explanation of the drawing]

Figures 1 and 2 show one of the apparatuses for carrying out the method of the present invention.
An example layout diagram, Figure 3 is an explanatory diagram of an example of the image of the slit beam projected onto the image receiver by the imaging camera, Figure 4 is a graph showing the relationship between the amount of movement and the amount of deviation during measurement, and Figure 5 The figure is an explanatory diagram of how to determine the amount of bending. Code 1... Underframe 1a... Long material 2... Floodlight 3... Imaging camera 4... Moving trolley 5... ... Drive motor 6 ... Wheels 7 ... Moving frame 8 ... Placement stand 9 ... Frame 1
0...Moving trolley 11...Wheel 12
... Image receptor 13 ... Ray image 14
・・・・・・Light image patent applicant Kawasaki Steel Co., Ltd. Agent Patent attorney Yoshikatsu Matsushita Lawyer Fumi Soe Shima Figure 7 □□C Figure 3 Figure 4 Figure f

Claims (1)

[Claims] The surface of a long material such as a round bar or shaped steel is irradiated with a slit beam or a laser beam from a projector perpendicular to its longitudinal direction, and the reflection of the irradiated beam [Gl is captured by an image camera, and the projector or When one of the long materials moves relative to the other, the amount of deviation of the reflected image from the fixed position is determined using the imaging camera, and the curvature of the long material is calculated from the deviation and the distance traveled. A method for detecting the amount of bending of a long material.