JPH07280529A - Non-contact type size-measuring apparatus - Google Patents

Abstract

PURPOSE:To provide a non-contact type size-measuring apparatus which enables accurate non-contact measurement of the size of an object to be measured being conveyed at a high speed on a conveying path in real time utilizing a scan beam of a laser and furthermore, enables lowering of cost. CONSTITUTION:A gate 3 is arranged sandwiching a.conveying path of an object 1 to be measured and a reflection member 4 is provided inside the gate 3 to make a reflection through an optical path almost the same with an incident optical path. Scan beams run from a plurality of scanner devices 5, 6, 7 and 8 toward the reflection member 4 to detect the quantity of light other than the scan beams intercepted by the object 1 to be measured located in the gate 3 for each of the scanner devices 5, 6, 7 and 8 utilizing the reflection of the reflection member 4. The size of the object 1 to be measured is measured based on a signal detected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-contact type size measuring device capable of measuring the size of an object to be measured which is being conveyed by using a laser beam.

[0002]

2. Description of the Related Art Conventionally, as a device for measuring the size of an object being conveyed, a device using a CCD camera, for example, a measuring device using a scanner device using a laser beam as a light source and a CCD camera, or a linear device. A measuring device using a scanner device that uses illumination as a light source and a CCD camera is known. In these apparatuses, a laser beam or a scanning beam of linear illumination is applied onto the object to be measured, and this is scanned in one dimension. Then, the scanning beam is observed by the CCD camera from above the object to be measured, and the image data on the CCD is output to the signal processing unit for comparison with the database. The serial time signal input to the signal processing unit is converted into a distance (or a dimension), and the size of the measured object is calculated and displayed on the display unit.

[0003]

DISCLOSURE OF INVENTION Problems to be Solved by the Invention In the non-contact type size measuring device using the CCD camera as described above,
When measuring the vertical and horizontal sizes of an object to be measured, since the number of desired data, that is, the number of dimensions of the measuring element increases, the number of scanner devices and CCD cameras described above must be increased. It is inevitable to increase the size of the equipment because the number of installation places must be increased. Further, in the apparatus of such a system, it takes a long time for the signal processing from the CCD element to the signal processing section, and as long as the CCD element is used, it is difficult to increase the conveying speed, and work efficiency is improved. There is a problem that you can not.

The present invention has been made in view of the above-mentioned problems, and the size of the object to be measured, which is conveyed at a high speed on the conveying path such as the roller or the belt conveyor, is real-time and non-contact with a simple structure. The purpose is to measure and determine the size of the object to be measured based on this measurement data. Further, it is another object of the present invention to provide a measuring device which is capable of speeding up the measuring device, improving accuracy, strengthening an algorithm, and introducing fuzzy control by using this technique, as compared with a conventional device.

[0005]

In order to solve the above problems, in a size measuring apparatus according to the present invention for measuring the size of an object to be measured which is being conveyed in a fixed direction in a non-contact manner, And a scanning unit disposed on one side of the gate for scanning the laser beam in a fan shape from a predetermined position to eject the DUT longitudinally, and a gate disposed on the other side of the gate. A reflecting means for reflecting the laser beam from the scanning means through an optical path substantially the same as the incident optical path; and a detecting means for receiving the laser beam reflected from the reflecting means without being blocked by the object to be measured, It is characterized in that the size of the object to be measured is measured based on a signal indicating whether or not the laser beam is received by the detection means. In detail, the scanning means and the detection means are composed of a scanner device provided as an integrated unit, and the boundary positions of the dark and light portions of the object to be measured by the laser beams emitted from at least two scanner devices and each scanner. Is detected by each of the detection means, and the size of the object to be measured is measured based on this signal. Further, the reflecting means is a reflecting member having a regression characteristic and has a function of reflecting in the same direction with respect to the incident angle of the scanning beam, and the scanner device is provided on the bottom surface of the object to be measured. First and second scanner devices, which are arranged at a predetermined interval at positions on the extension line, and third and third scanner devices, which are arranged at a position lower than the bottom surface of the object to be measured and are opposed at a predetermined interval. 4 scanner device, and the scanner device is arranged in a direction perpendicular to the conveyance direction of the object to be measured. Furthermore, the gate has a shape that straddles the conveyance path of the object to be measured, and the reflecting means is a reflecting member attached to the inner surface of the gate, and is provided in a direction perpendicular to the conveyance direction of the object to be measured. It is characterized by

[0006]

In such a structure, a fan-shaped scanning beam is scanned in the direction of the reflecting member from one or a plurality of scanner devices arranged at a predetermined position in a direction perpendicular to the conveying direction of the object to be measured. The object to be measured is conveyed into the frame to which the reflecting member is attached, and the two upper edges of the object to be measured are blocked by the scanning beams emitted from the scanner devices arranged at different positions. The change in the amount of light blocked by the scanner device and the object to be measured is sent to the detecting means of each scanner device by the scanning beam reflected from the reflecting member. This signal is sent to the signal processing unit, and the angle of the boundary between light and dark that is blocked by the scanner device and the object to be measured is obtained. From this angle and the known position of the scanner device, the size of the object to be measured is calculated in real time by trigonometry.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of a non-contact type size measuring apparatus according to the present invention, which includes a roller 2 that conveys an object to be measured 1 in a constant conveying direction (direction perpendicular to the object to be measured) as a conveying means. A gate 3 arranged so as to surround the DUT 1 in a direction perpendicular to the transport direction thereof and a laser beam, which will be described later, provided on the inner surface of the gate 3 in a direction substantially the same as the incident angle, that is, an optical path substantially the same as the incident optical path. A planar reflecting member 4 that reflects through and an upper surface of the roller 2 (measurement object 1
Bottom surface of the first and second scanner devices 5 and 6, and third and fourth scanner devices 7 and 8 arranged below the scanner devices 5 and 6 with a predetermined distance. Have and.

The object 1 to be measured can be suitably measured in a shape having a rectangular parallelepiped or a cubic edge, and as a conveying means, a means such as a roller or a belt for conveying the object to be measured at a constant speed is used. To be At this time, it is desirable that the DUT 1 is regulated by, for example, a guide plate and conveyed straight to a predetermined position in the measuring device before reaching the non-contact size measuring device of the present invention.

The scanner devices 5 to 8 have substantially the same structure, and an example thereof will be described with reference to the block diagram of the scanner device shown in FIG. The scanner devices 5 to 8 are
A laser light source 9 that emits a laser beam, a scanning unit that scans the laser beam on the reflecting member 4, and a unit that detects the laser beam returning from the reflecting member 4 are integrally provided. The laser beam emitted from the laser light source 9 is reflected by the half mirror 10 and projected on the polygon mirror 11 rotating at a constant speed. The polygon mirror 11 forms a scanning unit that receives the laser beam and scans the scanning beam on the reflecting surface of the reflecting member 4.

The scanning beam scanned by the polygon mirror 11 is reflected by a reflecting member 4 such as a planar reflecting tape (corner cube prism array, also known as retroreflector). The planar reflecting member 4 has a regressive characteristic of reflecting light at an arbitrary position in the direction of the incident light through almost the same optical path as the incident optical path. Figure 4
Shows the reflection efficiency of the reflection pattern with respect to the scanning direction of the scanning beam, and it can be seen that the reflected light is reflected almost in the direction of the incident light. The scanning beam that hits the reflecting member 4 is reflected toward the polygon mirror 11. Therefore, even if a plurality of scanner devices are provided at different positions to scan the scanning beam, the reflected scanning beams respectively return to the ejecting scanner device, and the scanning beams of other scanner devices are erroneously recognized. There is nothing to do.

In FIG. 2, the beam that reaches the polygon mirror 11 and is reflected is condensed by the condenser lens 12 on the light receiving sensor 13. When the DUT 1 being conveyed enters the scanning range formed between the scanning beam scanned by the polygon mirror 11 and the reflection means, the scanning beam is blocked by the DUT 1. Therefore, the light receiving sensor 13
The amount of the reflected scanning beam that reaches the position decreases. The signal input to the light receiving sensor 13 is output to a signal processing unit (not shown) as a value in comparison with the range blocked by the DUT 1.

FIG. 3 shows an example of another scanner device using the light receiving flat plate mirror 14 instead of the half mirror. Also in this scanner device, the laser light source 9, the scanning means, and the detecting means are provided as an integrated unit as in the above.
A light-receiving flat plate mirror 14 having a slit 30 is arranged in front of the polygon mirror 11 which is a scanning means. The light-receiving flat plate mirror 14 has a gap S through which the scanning beam passes along the scanning axis direction, and the beam reflected by the reflecting member 4 serves as a photodiode 1 as a light-receiving sensor.
It is arranged with a tilt angle at a position where it is reflected by 5.
A laser beam emitted from the laser light source 9 is rotated at a constant speed by a total reflection mirror 16 and is a polygon mirror 11.
Projected on. The scanning beam converted by the polygon mirror 11 passes through the slit 30 of the light receiving flat plate mirror 14 and is scanned in a fan shape toward the reflecting member 4. The scanning beam that has reached the reflecting member 4 is reflected by the reflecting member 4 in the direction of the polygon mirror 11 and reaches the light receiving flat plate mirror 14 located in front of the polygon mirror 11.
This reflected beam is due to light diffusion or defocusing,
The diameter is increased and it is reached. Therefore, the diameter of the reflected beam becomes larger than that of the slit 30 provided in the light-receiving flat plate mirror 14, and a part that does not pass through the slit 30 is reflected in the direction of the photodiode 15, and the light amount of the reflected beam is detected. In this case, since the half mirror 10 shown in FIG. 2 is not used, the loss of the light amount due to the half mirror is small, the accuracy of the output light amount change signal is improved, and the measurement accuracy can be improved.

Next, the measuring principle of the non-contact type size measuring apparatus according to the present invention will be described with reference to FIG. Each of the four scanner devices 5 to 8 described above scans a fan-shaped scanning beam in a predetermined range toward the reflecting member 4 attached to the inside of the rectangular gate 3. When the DUT 1 is conveyed and enters the gate 3 where the scanning beam is scanned, the scanning beams emitted from the respective scanner devices 5 to 8 are only the portions blocked by the DUT 1. Be cut off. Scanning beams other than the blocked beam are reflected by the reflecting member 4 and return to the scanner devices 5 to 8. The light amounts of these reflected beams are detected, and the angles α1, α2, β1 blocked by the edges of the DUT 1 from the scanner devices 5 to 8 are determined from the ratio with the light amount in the scanning range when the DUT 1 is not present. , Β2 are obtained by a signal processing device (not shown), and the size (width W,
Find the height Y).

When measuring an object 1 having a height Y and a width W, the distance between the scanner devices 5 and 6 and 7 and 8 is D, and the distance between the scanner devices 5 and 7 and 6 and 8 is H. And D = X1 + X2 + W, the size of the DUT 1 can be obtained by the following equation. The scanning beam of the first scanner device 5 blocks the edge 20 of the object to be measured, and the relationship between the angles α1 and X1 and Y formed by this is: X1 = Ycotα1 (1) Scanning of the second scanner device 6 The beam intercepts the edge 21 of the object to be measured, and the angle α2 formed by this
X2 = Ycotα2 (2) The angle β1 formed by the edge 20 of the object to be measured is blocked by the scanning beam of the third scanner device 7
And X1 and (Y + H) have the following relationship: X1 = (Y + H) cotβ1 (3) The angle β2 formed by the edge 21 of the object to be measured blocked by the scanning beam of the fourth scanner device 8
And X2, (Y + H) are expressed as follows: X2 = (Y + H) cotβ2 (4) The height Y and the width W of the object to be measured are calculated from the equations (1) to (4).
Is calculated by the following equation. Y = [H (cotβ1 + cotβ2)] / [cotα1
+ Cotα2-cotβ1-cotβ2] (5) W = D−H [(cotβ1 + cotβ2) (cotα1
+ Cotα2)] / [cotα1 + cot
α2-cotβ1-cotβ2] (6)

FIG. 5 is a perspective view of a non-contact type size measuring device according to the present invention. The DUT 1 is conveyed in a fixed direction by the roller 2 that is a conveying unit. A gate 3 to which a reflecting member is attached is provided at the measurement position, and four scanner devices 5 to 8 are arranged at predetermined intervals. When the DUT 1 passes through the gate, the scanning beam emitted from each of the scanner devices 5 to 8 is scanned by the DUT 1, and the scanning beam other than the portion blocked by the DUT 1 is reflected by the reflecting member 4. And is returned to the scanner devices 5 to 8 again. The change in the amount of light is detected by the photosensor, and the angle α of the boundary portion blocked by the DUT 1 from each of the scanner devices 5 to 8 by the signal processing device (not shown)
1, α2, β1, and β2 are calculated, and based on these data, calculation is performed by the above-described calculation method and the result is displayed on a display unit (not shown).

As another embodiment, the transport device 22 for the object to be measured 1 is inclined as shown in FIG. 6 so that the side surface 23 of the object to be measured 1 is always fixed, so that two scanners are provided. The size of the object to be measured can be measured only by using the devices 5 and 7.

Further, as shown in FIG. 7 in which the apparatus 22 for conveying the object to be measured is viewed from above, a guide device 25 formed of, for example, a bearing and a belt is provided in the transportation path and extends parallel to the transportation direction. The one surface of the DUT 1 randomly placed on the transport device 22 is biased in the direction of arrow A so as to be pressed against the surface 25a of the guide device 25 during the transportation, thereby measuring the DUT 1 in size. Position it straight against the device. In this state, the DUT 1
The position of the side surface 23 is constant, and the size of the DUT 1 may be measured by the two scanner devices 5 and 7 described above on the basis of this.

Further, when the object to be measured 1 to be conveyed is not conveyed straight in the conveying direction, the scanning beam is scanned as shown in FIG. 8 and the above-described method is performed using the four scanner devices 5 to 8. The size of the DUT 1 is measured. In this case, since the DUT 1 is conveyed obliquely to the measuring device, the measured size is the cross section L obtained by cutting the DUT 1 obliquely. When the maximum size of this data is detected, the inclination θ of the measured object 1 with respect to the conveying direction is obtained from the transport speed of the measured object 1 and the positional change between the measured object obtained by the scanner devices 5 to 8, and the actual measured object is measured. Width W
Can be calculated.

In this embodiment, the scanner devices 5 and 7
Although (6 and 8) are arranged in the vertical direction to calculate the angle blocked by the object to be measured, for example, they may be arranged in the horizontal direction, and the positional relationship between the position of the scanner device and the object to be measured is clear. The installation location of the scanner device is not limited as long as it can be defined. Further, in addition to measuring the shape of the rectangular parallelepiped described in the present invention, it is applied to sorting by distribution home delivery system, width measurement of rubber, film, etc., detection of tire shape, width measurement of steel plate, meandering control, pinhole measurement, etc. can do.

[0020]

The non-contact type size measuring device of the present invention comprises:
The size of the object to be measured during high-speed transportation could be measured in real time with a simple configuration that does not require a CCD camera. In addition, since only the reflecting means is attached to the upper part of the device, that is, the gate, the weight applied to the upper part is reduced as compared with the conventional device having a built-in CCD element, so that the device can be mounted or the device has good strength. Could be provided. Furthermore, since the light source, the scanning means, and the detection means that form the scanner device are formed as an integrated unit,
Easy to maintain.

[0021]

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment according to the present invention.

FIG. 2 is a block diagram showing the structure of a scanner device.

FIG. 3 is a block diagram showing the structure of another scanner device.

FIG. 4 is a diagram showing efficiency of a reflection pattern with respect to a scanning direction of a scanning beam.

FIG. 5 is a perspective view showing an embodiment according to the present invention.

FIG. 6 is a block diagram showing another embodiment according to the present invention.

FIG. 7 is a top view showing another embodiment according to the present invention.

FIG. 8 is a block diagram showing another embodiment according to the present invention.

[Explanation of symbols]

 1 DUT 2 Roller 3 Gate 4 Reflecting member 5-8 Scanner device 9 Laser light source 10 Half mirror 11 Polygon mirror 22 Conveying device 25 Guide device

Claims (5)

[Claims] 1. A size measuring device for measuring the size of an object to be measured which is being conveyed in a fixed direction in a non-contact manner,
A gate disposed across the conveyance path of the object to be measured; a scanning unit disposed on one side of the gate to scan the laser beam in a fan shape from a predetermined position to vertically emit the object to be measured; A reflecting means provided on the other side of the reflecting means for reflecting the laser beam from the scanning means through an optical path substantially the same as the incident optical path; and a detecting means for receiving the laser beam reflected from the reflecting means without being blocked by the object to be measured. And a means for measuring the size of the object to be measured based on a signal indicating whether or not the detection means receives the laser beam. 2. The scanning means and the detection means are composed of a scanner device provided as an integrated unit, and each of the boundary positions of the light and dark parts of the object to be measured by the laser beams emitted from at least two scanner devices. The non-contact type size measuring apparatus according to claim 1, wherein the angle with respect to the scanner is detected by each detecting means, and the size of the object to be measured is measured based on this signal. 3. The non-contact according to claim 1, wherein the reflecting means is a reflecting member having a regression characteristic and has a function of reflecting in the same direction with respect to the incident angle of the scanning beam. Mold size measuring device. 4. The scanner device includes first and second scanner devices arranged at a position on an extension line of the bottom surface of the object to be measured with a predetermined gap, and a position lower than the bottom surface of the object to be measured. A third scanner device and a fourth scanner device which are arranged to face each other with a predetermined interval, and the scanner device is arranged in a direction perpendicular to the conveyance direction of the object to be measured. The non-contact type size measuring device according to claim 1. 5. The gate has a shape straddling a conveyance path of the object to be measured, and the reflecting means is a reflecting member attached to an inner surface of the gate, and is perpendicular to a conveying direction of the object to be measured. The non-contact size measuring device according to claim 1, wherein the size measuring device is provided in