JPH07198338A - Length measuring apparatus for part - Google Patents

Abstract

PURPOSE:To measure the lengths of many parts continuously and accurately without contact and to detect defective parts and falsely entered parts by measuring the amount of the movement of a conveying means between the passing timings of the front end and the rear end of the length measuring part of a part to be measured in conveyance over a fixed measuring point. CONSTITUTION:At a mounting surface B for a part to be measured in a conveying means 3 such as a conveyer belt, a length measuring part A of a part to be measured 2, which is sequentially supplied with a supplying means 1, is made to agree with the conveying direction. The part is conveyed one by one with an interval being provided. A passage detecting non-contact sensor 4 detects the passing timings of a front end C and a rear end D of the length measuring part A of the part to be measured 2, which is mounted on the mounting surface B and conveyed, over a fixed measuring point E. An optical moving- amount measuring part 5 measures the moving amount of the mounting surface B between the passing timings of the front end C and the rear end D without contact and operates the length of the measuring part A. A discharging means 6 discharges the defective part or the erroneouly mixed part detected by the measurement of the length of the part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a component length measuring apparatus for continuously and automatically measuring the lengths of a large number of components in a non-contact manner and detecting defective products or erroneous mixed products.

[0002]

2. Description of the Related Art Conventionally, when measuring the length of a part to be measured, the contact measuring method using scratches, micrometer, etc. can be used to measure one by one manually or automatically.
Since it is necessary to contact each measuring device one by one and perform the measurement, there is a problem that it takes a long time.

Recently, a non-contact measurement method has been attempted as a measure for increasing the speed.

[0004]

However, the automation of the component length measurement by the non-contact measurement which has been attempted conventionally is a method of obtaining the length of the component to be measured from the image information. Therefore, for example, a CCD camera is used. However, when calculating from image data, there is a problem that the difference in the reflection state due to the difference in the illumination angle and the material and shape of the surface and the influence of the shadow due to the thickness and uneven shape of the part under measurement are unavoidable and the accuracy decreases. is there.
Further, there is a problem similar to that of the CCD camera when calculating from the shadow of the laser beam and the shape of the transmitted light.

Further, these methods have a problem that it is necessary to accurately stop the component to be measured at a predetermined position, and it takes time and equipment cost to move, stop, and hold the component to be measured.

The present invention solves the above-mentioned problems, and measures the lengths of a large number of parts continuously and accurately by a non-contact method to detect defective products and erroneous mixed products. An object is to provide a length measuring device.

[0007]

In order to solve the above-mentioned problems, the component length measuring apparatus of the present invention mounts the supply means for sequentially supplying the measured parts and the supplied measured parts. Conveying means for conveying the length-measuring portion of the part to be measured and the conveying direction at a time, one by one, and a front end of the length-measuring portion of the part to be measured placed and conveyed on the conveying means. A non-contact sensor for detecting the timing at which the rear end and the rear end pass a fixed measurement point, and the amount of movement of the measured component placement surface of the transfer means between the front end transit timing and the rear end transit timing is non-contact An optical movement amount detection unit for measuring is provided.

Further, in order to solve the above-mentioned problems, the component length measuring apparatus of the present invention is such that the optical movement amount detection section includes a laser light source for irradiating a laser beam onto the component mounting surface of the conveying means to be measured.
A line sensor that receives the reflected laser light and detects the moving speed of the fine crepe-shaped light and dark pattern of the speckle pattern caused by the interference of the reflected laser light, and the time from the front end passing timing to the rear end passing timing and the moving speed. It is preferable to include a component length calculating means for calculating the length of the length measuring portion of the measuring component.

In order to solve the above-mentioned problems, in the component length measuring apparatus of the present invention, the optical movement amount detecting section includes a laser light source for irradiating a laser beam onto the component mounting surface of the conveying means.
A line sensor that receives the reflected laser light and detects the minute distance that the fine crepe-shaped light and dark pattern of the speckle pattern generated by the interference of the reflected laser light moves at every predetermined minute time, and the minute distance from the front end passage timing to the rear end. It is preferable to include a component length accumulating means for accumulating over the passage timing to obtain the length of the length measurement portion of the component to be measured.

[0010]

The automation of the length measurement of parts by the optical length measurement method, which has been attempted in the past, is a method of directly measuring the length of the parts. Therefore, as described above, it is necessary to temporarily stop each measurement of each part. It is difficult to increase the speed, and the adverse effect of the measurement accuracy deterioration caused by the unevenness of the surface of the part to be measured, the reflection condition of the surface, the curved state, the illumination angle, etc. is unavoidable. The long device does not directly measure the length of the part, but divides the measurement into two indirects, while
The passage detection non-contact sensor detects the front end passage timing and the rear end passage timing at which the front end and the rear end of the length measuring portion of the component to be measured placed and conveyed on the conveying means pass the fixed measurement point, and the other Thus, the optical movement amount detection unit indirectly obtains the length by measuring the movement amount of the measured component placement surface of the conveyance means that moves between the two timings. Since there is no need to stop, speeding up is easy, and the adverse effects due to the unevenness or curved state of the surface of the measured component, the illumination angle, etc. can be completely eliminated.

Further, what the optical movement amount detecting section measures is
In the prior art, the moving speed of the measured component itself, that is, the moving amount of the measured component itself, that is, the moving amount of the measured component itself, the rotational speed of the drive pulley of the conveying means such as a belt, the encoder, etc. The error due to belt slip and elongation, which is unavoidable when measured indirectly by measuring with, can be eliminated.

In addition, the optical movement amount detection section receives a reflected laser beam from the laser light source for irradiating the component mounting surface of the transfer means with the laser beam and the speckle pattern finely generated by the interference of the reflected laser beam. A line sensor for detecting the moving speed of the crepe-shaped light and dark pattern, and a part length calculating means for calculating the length of the length measuring portion of the measured part from the time from the front end passing timing to the rear end passing timing and the moving speed. In the case of the configuration including, it is possible to increase the moving speed of the measured component mounting surface of the conveying means up to the measurable speed of the line sensor, and it is possible to significantly increase the component length measurement.

Further, the optical movement amount detecting section receives a reflected laser beam from the laser light source for irradiating the component mounting surface of the carrying means with the laser beam, and the speckle pattern finely generated by the interference of the reflected laser beam. A line sensor that detects a minute distance in which the crepe-shaped light and dark pattern moves at every predetermined minute time,
In the case of a configuration including a component length integrating means that integrates these minute distances from the front end passage timing to the rear end passage timing and integrates the length of the length-measuring portion of the component under measurement,
It is not necessary that the moving speed of the surface of the carrying means on which the component to be measured is placed is constant, and even if the moving and stopping are repeated, the same length measurement value can be obtained.

[0014]

Embodiments FIGS. 1 to 5 show an embodiment of a component length measuring device according to the present invention.
It will be described based on.

FIG. 1 is a side view showing a main part of the structure of the component length measuring apparatus of this embodiment, and FIG. 2 is a plan view thereof.

In FIG. 1 and FIG. 2, the supply means 1 sequentially supplies the parts to be measured 2 and the conveying means 3 such as a conveyor belt.
The measured component placement surface B of the measured component 2 on which the above-mentioned supplied measured component 2 is placed and the measuring direction of the measured portion A of the measured component 2 is aligned with the conveying direction at intervals of one by one. Transport. In order to match the above directions, a guide that matches the shape of the measured part 2 may be provided on or above the measured part mounting surface B, and when the measured part 2 is rod-shaped, the measured part is not measured. A simple groove such as a groove in the carrying direction on the component mounting surface B may be used. If the shape is different, a recess or a guide corresponding to the shape is provided. In the passage detection non-contact sensor 4, the front end C and the rear end D of the length-measuring portion A of the measured component 2 placed and conveyed on the measured component placement surface B of the conveying means 3 pass through the fixed measurement point E. Detect the timing to do. As the passage detecting non-contact sensor 4, a photoelectric sensor is used as shown in FIG. The optical movement amount detection unit 5 optically non-contactly measures the movement amount of the component mounting surface B to be measured of the conveying means 3 between the front end passage timing and the rear end passage timing. The discharging means 6 discharges a defective product or an erroneously mixed product detected by the component length measurement.

The optical movement amount detecting section 5 may be of any type and may have any structure, but in the present embodiment, the following structure is used. That is, as shown in FIG.
Laser light source 9 for irradiating the measured component mounting surface B with a laser beam, and a line sensor 10 for receiving the reflected laser beam and detecting the moving speed of the fine crepe-shaped light and dark pattern of the speckle pattern caused by the interference of the reflected laser beam. And an optical movement amount detection means including a component length calculating means 7 for calculating the length of the length-measuring portion A of the component 2 to be measured from the moving speed and the time from the front end passage timing to the rear end passage timing. Part 5
a, or, as shown in FIG. 4, a laser light source 9 for irradiating a laser beam onto the component mounting surface B to be measured of the conveying means 3 and a speckle pattern generated by the interference of the reflected laser light by receiving the reflected laser light. A line sensor 10 for detecting a minute distance in which a fine crepe-like light and dark pattern moves at every predetermined minute time;
An optical movement amount detection unit 5b provided with a component length integrating means 8 for integrating these minute distances from the front end passage timing to the rear end passage timing to integrate the length of the length measurement portion A of the component to be measured 2. use. The position on the measured component placement surface B of the conveyance means 3 where the optical movement amount detection unit 5 measures the movement amount is the measured component placement surface B of the conveyance means 3.
Can be at any position as long as it can be determined that the velocity is equal to the velocity passing through the fixed measurement point E, and this condition is satisfied,
Moreover, a position convenient for installation can be selected.

The operation of the optical movement amount detector 5a will be described with reference to FIGS.

The speckle pattern is an interference fringe with a fine crepe-shaped light and dark pattern, and each photosensitive element of the line sensor 10 of FIG. 3 constituted by arranging the photosensitive elements in a line is bright as shown in FIG.・ Divided into dark and digitize data as 1 for light and 0 for dark. This speckle pattern is
Since it moves along with the movement of the measured part placement surface B of the transfer means 3, a specific light / dark combination in FIG. 5, for example, c in FIG.
Focusing on (1101), (1) to (2) in FIG.
Since it moves as in (3), the moving speed of c can be calculated.

According to the optical movement amount detector 5a, the optical movement amount detector 5a can be moved up to the upper limit at which the movement speed can be measured. Actually, it is possible up to about 4 m / sec.

The operation of the optical movement amount detector 5b will be described with reference to FIGS.

As shown in FIG. 5, each photosensitive element of the line sensor 10 shown in FIG. 4 in which the photosensitive elements are arranged in a line is divided into bright and dark, and the data is 1 for bright and 0 for dark. Turn into. This speckle pattern is transferred by the transport means 3.
Since it moves along with the movement of the measured part mounting surface B of FIG.
Specific light and dark combination of, for example, c (1101) in FIG.
Focusing on (1), the distance moves from (1) to (2) and (3) in FIG. 5, so the distance that c moves can be obtained at every predetermined minute time. The component length integration means 8 can integrate these minute distances from the front end passage timing to the rear end passage timing to integrate the length of the length measurement portion A of the measured component 2.

According to the optical movement amount detector 5b, the conveying speed of the conveying means 3 does not have to be constant, and the length measurement value is the same even if the movement / stop is repeated. Higher speed is possible, and the actual result is about 1 m / sec, and the resolution is about ± 0.5% of the measurement length of the measured component.

[0024]

The component length measuring device of the present invention does not directly measure the length of the component, but divides the measurement into two parts and indirectly, while the passage detection non-contact sensor is mounted on the conveying means. The front end and the rear end of the length-measuring portion of the measured part to be placed / conveyed detect the front-end passage timing and the rear-end passage timing when passing the fixed measurement point, while the optical movement amount detection unit Since the length is indirectly obtained by measuring the amount of movement of the measured part placement surface of the conveyance means that moves between both timings, there is no need to stop it once, and speeding up is easy. It is possible to completely remove the adverse effects due to the unevenness and the curved state of the surface of the measurement component, the illumination angle, the reflection condition, and the like.

Further, since the optical movement amount detecting means measures the movement amount of the measured component mounting surface of the conveying means, that is, the movement amount of the measured component itself, although indirectly, the conventional technique is used. It is said that it is possible to completely eliminate the error due to belt slip and elongation, which is inevitable when the moving speed of the measured part is indirectly obtained by measuring the rotational speed of the drive pulley of the conveying means such as a belt with an encoder or the like. Produce an effect.

Further, the optical movement amount detecting section receives the reflected laser light from the laser light source for irradiating the measured component mounting surface of the conveying means with the laser light, and the speckle pattern finely generated by the interference of the reflected laser light. A line sensor for detecting the moving speed of the crepe-shaped light and dark pattern, and a part length calculating means for calculating the length of the length measuring portion of the measured part from the time from the front end passing timing to the rear end passing timing and the moving speed. In the case of the configuration including, it is possible to increase the moving speed of the measured component mounting surface of the transporting unit up to the measurable speed of the line sensor, and it is possible to achieve extremely high speed measurement of the component.

Further, the optical movement amount detecting section receives a reflected laser beam from the laser light source for irradiating the measured object mounting surface of the conveying means with the laser beam, and the speckle pattern finely generated by the interference of the reflected laser beam. A line sensor that detects a minute distance in which the crepe-shaped light and dark pattern moves at every predetermined minute time,
In the case of a configuration including a component length integrating means that integrates these minute distances from the front end passage timing to the rear end passage timing and integrates the length of the length-measuring portion of the component under measurement,
It is not necessary that the moving speed of the measured part mounting surface of the conveying means is constant, and the same length measurement value can be obtained even if the moving and stopping are repeated.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of a component length measuring device of the present invention.

FIG. 2 is a plan view of FIG.

FIG. 3 is a detailed view of a main part of FIG.

FIG. 4 is a detailed view of a main part of FIG.

5 is a diagram showing the operation of FIG. 1. FIG.

[Explanation of symbols]

 A Length measurement part B Measured part mounting surface C Front end D Rear end E Fixed measuring point 1 Supply means 2 Measured part 3 Conveying means 4 Passage detection non-contact sensor 5, 5a, 5b Optical movement amount measuring part 7 Part length Calculation means 8 Component length integration means 9 Laser light source 10 Line sensor

Claims (3)

[Claims] 1. A supply means for sequentially supplying parts to be measured,
A carrier means for mounting the above-mentioned supplied parts to be measured, and for conveying the parts to be measured at intervals of one by combining the length measuring direction and the conveying direction of the length measuring part of the parts to be measured; A non-contact passage detection sensor that detects the timing at which the front end and the rear end of the length-measuring portion of the measured part to be conveyed pass a fixed measurement point, and the conveyance means between the front end passage timing and the rear end passage timing. A component length measuring apparatus, comprising: an optical movement amount detection unit that measures the movement amount of a measured component placement surface in a non-contact manner. 2. The optical movement amount detection section includes a laser light source for irradiating a laser beam onto a surface of the carrying means on which the component to be measured is placed, and a speckle pattern finely generated by interference of the reflected laser beam with the reflected laser beam. A line sensor for detecting the moving speed of the crepe-shaped light and dark pattern, and a part length calculating means for calculating the length of the length measuring portion of the measured part from the time from the front end passing timing to the rear end passing timing and the moving speed. The component length measuring device according to claim 1, further comprising: 3. The optical movement amount detection unit includes a laser light source that irradiates a laser beam on a component mounting surface of the transfer unit, and a speckle pattern that is generated by interference of the reflected laser beam and the reflected laser beam. A line sensor that detects a minute distance in which a crepe-like light and dark pattern moves at a predetermined minute time, and a component that integrates these minute distances from the front end passage timing to the rear end passage timing to obtain the length of the measured portion of the measured part. The component length measuring apparatus according to claim 1, further comprising a length integrating unit.