JPS6176941A - Method and device for inspecting appearance failure of screw - Google Patents

Method and device for inspecting appearance failure of screw

Info

Publication number
JPS6176941A
JPS6176941A JP19908384A JP19908384A JPS6176941A JP S6176941 A JPS6176941 A JP S6176941A JP 19908384 A JP19908384 A JP 19908384A JP 19908384 A JP19908384 A JP 19908384A JP S6176941 A JPS6176941 A JP S6176941A
Authority
JP
Japan
Prior art keywords
screw
binarized
signal
appearance
side development
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP19908384A
Other languages
Japanese (ja)
Other versions
JPH0535379B2 (en
Inventor
Michinaga Nagura
道長 名倉
Toshiharu Kamiya
神谷 敏玄
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Denso Corp
Original Assignee
NipponDenso Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by NipponDenso Co Ltd filed Critical NipponDenso Co Ltd
Priority to JP19908384A priority Critical patent/JPS6176941A/en
Publication of JPS6176941A publication Critical patent/JPS6176941A/en
Publication of JPH0535379B2 publication Critical patent/JPH0535379B2/ja
Granted legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01BMEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B11/00Measuring arrangements characterised by the use of optical techniques
    • G01B11/24Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
    • G01B11/2425Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures of screw-threads
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01BMEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B11/00Measuring arrangements characterised by the use of optical techniques
    • G01B11/02Measuring arrangements characterised by the use of optical techniques for measuring length, width or thickness
    • G01B11/024Measuring arrangements characterised by the use of optical techniques for measuring length, width or thickness by means of diode-array scanning

Abstract

PURPOSE:To discriminate a defective part with high accuracy, and also to improve the work efficiency by detecting the side face development graphic form of a screw. CONSTITUTION:Reflected light which has been irradiated from an illuminating device 1 and has been reflected by a screw 2 is converted to an electric signal through a line camera 6. An image signal inputting circuit 7 is controlled by a CPU10, and a video signal V1 is fetched by operating the camera 6. The signal V1 is synchronized with a scanning signal and sampled, and thereafter, binary-coded in accordance with bright and dark levels. The circuit 7 has a floating binary-coding circuit for varying a threshold value for binary-coding the signal V1, in accordance with its input signal. Also, the circuit 7 detects the one-dimensional bright and dark graphic form of the signal V1, and thereafter, rotates the screw 2 by a prescribed angle by sending out a control signal V2 to a motor driving circuit 9, and detects the one-dimensional bright and dark graphic form in other side face. Such an operation is stored continuously in an image memory 8, the side face development graphic of the screw 2 is obtained, various deformations on this side face development graphic form are discriminated 40, and a defect of the screw can be detected.

Description

【発明の詳細な説明】 [産業上の利用分野] 本発明はネジ山の欠損等の外観不良を検査する方法及び
その装置に関する。
DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method and apparatus for inspecting appearance defects such as missing threads.

[従来の技術] 従来、ネジの外観不良の検査は作業者の目i亮によって
検査するものであった。このため全てのネジ出について
見落づ事なく全周に渡り倹存しなければならず、検査時
間に多くの時間を必要としていた。
[Prior Art] Conventionally, defects in the appearance of screws have been inspected by the operator's eyes. For this reason, all the screws had to be kept around the entire circumference without being overlooked, which required a lot of inspection time.

C発明の解決しようとする間rn点] 本光明は、従来の人間の目視による検査の不正確性の改
善及び検査時間を短縮するため、ネジの側面展開図、を
検出し、その側面展開図に表われたネジの特徴に基づい
て欠10部分を高精度で判別することを目的とする。
C points to be solved by the invention] In order to improve the inaccuracy of conventional human visual inspection and shorten the inspection time, the present invention detects the side development view of a screw, and detects the side development view of the screw. The purpose of this invention is to identify 10 missing portions with high accuracy based on the characteristics of the screw that appear in the figure.

c間官点を解決するための手段及び作用1本第1発明は
、検査方法の発明であり、ネジに特定方向から光を照射
し、該ネジの側部に置かれた映像センサによって、前記
ネジからの反射光を検出することにより該ネジの軸方向
に沿った一次元の明暗図形を検出し、 前記ネジと前記映像センナとの相対的回転により、#記
ネジの側面部の前記一次元明暗図形と、全周に渡り検出
することにより、前記ネジの側面展開図形を1qて、該
側面展開図形から前記ネジの外観不良を検査する検査方
法である。
The first invention is an invention of an inspection method, in which a screw is irradiated with light from a specific direction, and an image sensor placed on the side of the screw is used to inspect the screw. By detecting the reflected light from the screw, a one-dimensional light-dark figure along the axial direction of the screw is detected, and by the relative rotation of the screw and the image sensor, the one-dimensional shape of the side surface of the # marked screw is detected. This is an inspection method for detecting bright and dark figures over the entire circumference, thereby determining the side developed figure of the screw, and inspecting the screw for external appearance defects from the side developed figure.

ネジに対する光の照射は、ネジの山と谷の明暗図形を明
確に判別できるようにするためであり、その照射方向は
、ネジの軸に対して軸方向にやや傾斜した斜め方向から
照射するのが望ましい。その様に照射するとネジの山の
先端部分のみ明るくでき、ネジ山の欠損部は、隣りのネ
ジ山の影により、暗くすることができるので、欠局部を
正確に判定できる。然しながう、照射方向は特に限定す
るものではなく、ネジの軸に対して垂直な方向から照射
してもよい。この場合には、一般にネジ山先端と谷の底
部が明るくなり、ネジ山の傾斜部分が暗くなるが、ネジ
出に欠損がある場合には、反射角度が変化し明るい部分
が暗くなるか、又は暗い部分が明るくなるため不良部分
を検出することができる。
The light is irradiated onto the screw so that the bright and dark shapes of the peaks and valleys of the screw can be clearly distinguished. is desirable. By irradiating in this way, only the tip of the thread of the screw can be brightened, and the missing part of the thread can be darkened by the shadow of the adjacent thread, so that the missing part can be accurately determined. However, the irradiation direction is not particularly limited, and irradiation may be performed from a direction perpendicular to the axis of the screw. In this case, the tips of the threads and the bottoms of the valleys generally become brighter, and the sloped parts of the threads become darker, but if there is a defect in the thread extension, the reflection angle changes and the brighter parts become darker, or Since dark areas become brighter, defective areas can be detected.

ネジの軸方向に沿った一次元の明暗図形の検出には、テ
レビカメラ、ラインセンサ、エリアセンサ等を用いるこ
とができる。2次元図形を検出できるセンサの場合には
、軸方向の映像に対応した1走査信号によって検出され
る信号を抽出すれば良い。側面展開図形を得るには、軸
方向に沿った一次元明暗図形を検出しつつ、ネジと映m
 tンサとの相対的な位置関係を変化させる。例えばネ
ジを回転させる。このネジの側面展開図形は、信号連理
の便宜上、明暗レベルに対応して2値化するのが望まし
い。2値化された側面展開図形を用いて、ネジの形状に
関する特徴により、ネジの欠損部を抽出する。不良部の
抽出方法は、たとえば2値化された側面展開図形をその
ネジ線に冶って所定量移動させ、移動前後のパターンと
の間で排他的論理和をとる方法がある。叩ら、ネジの周
期性のない部分を、不良部として抽出することができる
。又、ネジの取付けが回転軸に対して傾いている場合に
は、側面展開図形に表われるネジ線は曲線となるので、
図形をネジ線に沿って移動させることが困難Cある。こ
の場合には、ネジ線の変形に追随して図形を補正しつつ
移動させる必要がある。即ら、展1;口図形において軸
方向の移動量と、袖6向に垂直な移!Ilf?tとにお
いで、軸方向に垂直な移動はを一定にし!、:場合、軸
方向の移動量を図形の各部にa3いてネジ線の変形に対
応して異なる(直とする。このような移動処理をすれば
、正規のネジ線は必f屯なる。従って、移動前後の展開
図との間で排他的論理和をとればその規Ill性に合わ
ない?JS分、即ち、欠10部が不良部として抽出され
る。
A television camera, line sensor, area sensor, etc. can be used to detect the one-dimensional bright and dark pattern along the axial direction of the screw. In the case of a sensor capable of detecting a two-dimensional figure, a signal detected by one scanning signal corresponding to an image in the axial direction may be extracted. To obtain a lateral developed figure, while detecting a one-dimensional bright and dark figure along the axial direction,
t change the relative positional relationship with the sensor. For example, rotating a screw. For convenience of signal processing, it is desirable that the side development figure of this screw be binarized in correspondence with the brightness level. Using the binarized side development figure, the missing part of the screw is extracted based on the features related to the shape of the screw. A method for extracting a defective part is, for example, a method in which a binarized side developed figure is attached to its screw line, moved by a predetermined amount, and exclusive OR is performed between the patterns before and after the movement. It is possible to extract the parts of the screws that are struck and have no periodicity as defective parts. Also, if the screw is installed at an angle to the rotation axis, the screw line that appears in the side development figure will be a curve, so
It is difficult to move the figure along the screw line. In this case, it is necessary to move the figure while correcting it following the deformation of the screw line. That is, Exp1: The amount of movement in the axial direction in the mouth figure and the movement perpendicular to the sleeve direction! Ilf? t and odor, the movement perpendicular to the axis is constant! ,: In the case, the amount of movement in the axial direction is a3 for each part of the figure and varies depending on the deformation of the screw line (straight).If such movement processing is performed, the regular screw line will necessarily be formed.Therefore, If an exclusive OR is performed between the development diagrams before and after the movement, the ?JS portion, that is, the missing 10 portions, will be extracted as defective portions.

また、本第2発明1よこれらの方法を実現するための装
置であり、その発明概念が第1図にブロックダイアグラ
ムとして表わされている。即ち本発明装置は、ネジ2に
特定方向から光を照射する照明装置1と、該ネジ2から
の反射光を検出することにより、該ネジ2の軸方向に沿
った一次元の明暗図形を検出する映像センサ6oと、前
記ネジ2を保持し、前記ネジ2と前記映像センサ60と
の相対的回転を制御する回転制御装!20と、前記回転
制御装置20を駆動し、前記ネジ2の側面部の前記一次
元明暗図形をネジの全周に渡り検出して明暗レベルに応
じて2値化した側面展開図形を1qる側面展開図形検出
装置30と、前記側面展開図形検出装置3oによって検
出された2圃化された側面展開図形を処理し、前記ネジ
2の外観の良否を判定するパターン判定装置40と、か
ら成るネジの外観不良検査装置である。
Further, the present second invention 1 is an apparatus for realizing these methods, and the inventive concept is represented as a block diagram in FIG. That is, the device of the present invention includes an illumination device 1 that irradiates light onto a screw 2 from a specific direction, and detects a one-dimensional light-dark pattern along the axial direction of the screw 2 by detecting reflected light from the screw 2. A rotation control device that holds the screw 2 and controls the relative rotation between the screw 2 and the image sensor 60! 20, and a side surface that drives the rotation control device 20, detects the one-dimensional light-dark figure on the side surface of the screw 2 over the entire circumference of the screw, and generates a side developed figure 1q that is binarized according to the light and dark level. A screw driver comprising a developed figure detecting device 30, and a pattern determining device 40 that processes the divided side developed figure detected by the side developed figure detecting device 3o and determines whether the appearance of the screw 2 is good or bad. This is an appearance defect inspection device.

本発明の装置の構成は、照明8置と、ネジの側面の一次
元明暗図形を検出する映像センサと、ネジを保持しその
イメージセンサとの相対的回転を制(II する回転制
御装置、及び側面展開図形を(与る側面展開図検出装置
、側面展開図形からネジの外観の良否を判定するパター
ン判定装置、とから成るものである。このうら照明装置
は、前記方法発明に述べた様に、望ましくは、ネジの軸
の方向に対しやや傾斜した方向から照射するのが望まし
い。
The configuration of the device of the present invention includes eight lights, a video sensor that detects a one-dimensional contrast pattern on the side of the screw, a rotation control device that holds the screw and controls its relative rotation with the image sensor, and This system consists of a side development view detection device that detects a side development figure, and a pattern judgment device that determines whether the external appearance of the screw is good or bad from the side development figure. It is desirable to irradiate from a direction slightly inclined to the direction of the axis of the screw.

又、パターン判定装置は萌述した手法を用いた装置が望
ましい。
Further, it is desirable that the pattern determination device uses the method described above.

[実施例] 以下、本発明を具体的な実施例に基づいて詳しく説明す
る。
[Examples] Hereinafter, the present invention will be described in detail based on specific examples.

第2図は本発明装置の具体的な1実施例に係る外観不良
検査装置の構成を示したブロックダイヤグラムである。
FIG. 2 is a block diagram showing the configuration of an appearance defect inspection device according to a specific embodiment of the device of the present invention.

第3図は、照明装置1、ネジ2゜ラインカメラ6との位
置関係を示した説明図である。照明装置1はネジ2の軸
13方向に対し、一定の傾斜(θ)した方向から照射し
ている。ラインカメラ6は、照明装置1とネジ2に対し
それらと同一平面上にあり、ネジ2に対し直角方向に設
()られている。この照明装置には、発光光量の変動の
少ないフィラメントランプを用いた。しかし、10 K
 I−I z以上の高周波蛍光灯の様に発光光量の変動
が映像センサ60の出力信号に影響を与えない光源を用
いることもできる。ネジ2はボルトを用いている。回転
かj御装首20は、ネジ2を固定するチャックを有した
ロータ3と、そのロータ3とモータ5を連結するシャフ
ト4と、ネジを回転させるモータ5及びモータ5を駆動
するモータ駆動回路9とから成る。映像センサ60には
、ラインカメラ6を用いている。ラインカメラ6は直線
上に配列された受光素子(COD)を用い、ネジ2から
の反射光を受光して電気信号に変換するっ側面展開図検
出技@30は、ラインカメラ6かjうの(8号を入力す
る画像信号入力回路7ど、画像信号入力回路7の出力信
号を記憶する画一メモリ8と、その両者を制御するCP
U 10と、処理プログラムを記憶したRAMl31と
から成る。ii!ii像信号入力回路7はCPU10に
よって制御され、ラインカメラ6を操作して映像信号v
1を取り出す。映像信号V1は走査信号と同期してサン
プリングされ、その後明暗レベルに対応して2値化され
る。画像信号入力回路7は、映像信号v1を2flri
化するしきい圃をその入力振幅に対応して変動するよう
イよn12侑イヒ回路を有している。又、画像信号入力
回路7は、1の一次元明暗図形を検出した後、モータ駆
動回路9にi、II III信号v2を送出して、所定
角Iどけネジを回転させる。所定角回転した後、同様に
他の側面における一次元明暗図形@検出づる1、この様
な動作を連続的に行い得られた一次元明110図形を連
抗して画像メモリ8に記憶し−C、ネジ2の側面展開図
形が得られる。又、パターン回定装置40は、CPU 
10と、その判定処理プログラムを記憶したR A M
 II 32とから成る。
FIG. 3 is an explanatory diagram showing the positional relationship between the illumination device 1 and the screw 2° line camera 6. The illumination device 1 emits light from a direction at a certain angle (θ) with respect to the direction of the axis 13 of the screw 2. The line camera 6 is located on the same plane as the illumination device 1 and the screw 2, and is installed in a direction perpendicular to the screw 2. This illumination device used a filament lamp with little variation in the amount of light emitted. But 10K
It is also possible to use a light source in which fluctuations in the amount of emitted light do not affect the output signal of the image sensor 60, such as a high-frequency fluorescent lamp of I-Iz or higher. The screw 2 uses a bolt. The rotating head 20 includes a rotor 3 having a chuck for fixing the screw 2, a shaft 4 connecting the rotor 3 and the motor 5, a motor 5 for rotating the screw, and a motor drive circuit for driving the motor 5. It consists of 9. A line camera 6 is used as the video sensor 60. The line camera 6 uses light receiving elements (COD) arranged in a straight line to receive the reflected light from the screw 2 and convert it into an electrical signal. (The image signal input circuit 7 that inputs the image signal input circuit 7, the uniformity memory 8 that stores the output signal of the image signal input circuit 7, and the CP that controls both of them.
It consists of U 10 and RAM 131 that stores processing programs. ii! ii The image signal input circuit 7 is controlled by the CPU 10 and operates the line camera 6 to input the video signal v.
Take out 1. The video signal V1 is sampled in synchronization with the scanning signal, and then binarized in accordance with the brightness and darkness levels. The image signal input circuit 7 receives the video signal v1 at 2flri
It has an input circuit so as to vary the threshold field to be changed in accordance with the input amplitude. Further, after detecting the one-dimensional contrast figure 1, the image signal input circuit 7 sends the i, II, and III signals v2 to the motor drive circuit 9 to rotate the I set screw by a predetermined angle. After rotating by a predetermined angle, one-dimensional bright and dark figures on the other side are detected in the same manner as shown in FIG. C, the side development figure of the screw 2 is obtained. Further, the pattern rotation device 40 is a CPU
10 and the RAM that stores the determination processing program.
II 32.

第4図はラインカメラ6によって検出される映l5(L
i号と、画像信号入力回路7によって2値化処L’[!
される2(1n信号と、それらの信号をネジの全周に渡
って検出してIJられた0I11面展開図形を示してい
る。第4図(a)に示すように照明装置1からh1射さ
れた光束21 i;Eネジ2のネジ山の先端部22のみ
照射さFL、ネジ山の先端部のみ光の反射が大きくなる
。その反射光23は第4図(b)に示す曲線24のよう
な光量分布を示している。曲線24は同時に、ラインカ
メラ6によって演出された映像信@V1の包絡線を表わ
している。映像信号v1は、入力された信号の振幅に応
じて適性に設定された21値化レベル25をしきい直と
して2値化される。その結果、第4図(C)に示すよう
に21値化された信号26が得られこの信号から一次元
明暗図形が得られる。次にモータ5を駆動して微小角度
、本実施例では1.8度づつ回転させ、それぞれの回転
角に応じて2脇化された信号26を検出する。その結果
第4図(d)に示すようにネジのl1ljI而展開図2
7がIJられるヮこの図でネジ山の部分は明部28であ
り、谷は暗部2つであり、明部は2値化符号の’ 1 
” 、暗部は″○′′で表されている。
FIG. 4 shows the image l5 (L) detected by the line camera 6.
i and the image signal input circuit 7 perform binarization processing L'[!
The figure shows the 2 (1n signals) to be detected and the 0I11 plane developed figure obtained by detecting these signals over the entire circumference of the screw.As shown in Fig. 4(a), the h1 radiation is The light flux 21 i; The curve 24 also represents the envelope of the video signal @V1 produced by the line camera 6.The video signal v1 is set appropriately according to the amplitude of the input signal. The resulting 21-value level 25 is used as the threshold to binarize the signal.As a result, a 21-value signal 26 is obtained as shown in FIG. 4(C), and a one-dimensional contrast figure is obtained from this signal. Next, the motor 5 is driven to rotate the motor 5 by minute angles (1.8 degrees in this example), and the signal 26 divided into two sides according to each rotation angle is detected.As a result, the signal 26 shown in FIG. ) As shown in Figure 2, the screw is expanded.
7 is IJ. In this figure, the thread part is the bright part 28, the valley is the two dark parts, and the bright part is '1' of the binary code.
”, dark areas are represented by ″○′′.

ネジ山に欠陥がある場合には、第5図(b)、(C)に
示すような信号が(りられる。即ち、ネジ山に欠陥35
が存在すると、入用光束21の反射光33の光量分布は
第5図(b)の曲線34に示すようになる。欠陥部35
は隣のネジ山の影に隠れ、光が照射されないので反射光
はiIVられない。
If there is a defect in the thread, a signal as shown in FIGS. 5(b) and (C) will be emitted.
, the distribution of the amount of reflected light 33 of the desired light beam 21 becomes as shown by the curve 34 in FIG. 5(b). Defect part 35
is hidden in the shadow of the adjacent screw thread and no light is irradiated, so the reflected light cannot be reflected.

従って、その部分の映像信QV1は暗レベルとなってい
る。2値化レベル36で映像信号v1を21値化すると
第5図(C)のような信号となり、ネジの欠陥35に対
応した明レベルの信号は財られない。
Therefore, the video signal QV1 of that portion is at a dark level. When the video signal v1 is converted into 21 values at the binarization level 36, a signal as shown in FIG. 5(C) is obtained, and the bright level signal corresponding to the screw defect 35 is not used.

又、第6図(a)に示すようにネジ山に打痕45が存在
する場合には、入射光束21は打痕45の表面で反射さ
れるが、変形のために、反射光43は、第6図(b)に
示すように、明部の位置が正規の位置からずれている。
Further, as shown in FIG. 6(a), when there are dents 45 on the screw thread, the incident light beam 21 is reflected on the surface of the dents 45, but due to the deformation, the reflected light 43 is As shown in FIG. 6(b), the position of the bright portion is shifted from the normal position.

これを2値化レベル46によって2蛸化すると、第6図
(C)に示すようになり、正常なネジ山の部分のネジピ
ッチ48と欠陥部分のネジピッチ49とは異なった値と
なる。
When this is binarized using the binarization level 46, it becomes as shown in FIG. 6(C), and the thread pitch 48 of the normal thread part and the thread pitch 49 of the defective part have different values.

以上の如きネジに欠陥がある場合には、その側面展開図
形は第7図のようになる。このうち53【、亥、ネジ山
の欠損によって光が反射されないような欠陥部分を表わ
し、54は打痕によるネジ山の一部が変形したような欠
陥を表わし、55はネジに異物等が(=J Wしている
ような欠陥を表わしてぃる。このような展開図形を処理
することによってネジの外観不良を検出することができ
る。第1には、各部におけるネジ線51のピッチを測定
することによって欠陥を検出することができる。第2に
は、図形を移動して中ね合せることにより、重ね合せら
れない部分を検出することにより欠陥を検出することが
できる。
If there is a defect in the screw as described above, its side development figure will be as shown in FIG. Of these, 53 [, 亥] represents a defective part where light is not reflected due to a missing screw thread, 54 represents a defect where a part of the screw thread is deformed due to a dent, and 55 represents a defect such as a foreign object on the screw ( = J W. By processing such a developed figure, it is possible to detect defects in the appearance of the screw. First, the pitch of the screw line 51 at each part is measured. Second, defects can be detected by moving and aligning the figures and detecting the portions that cannot be overlapped.

第8図は本実施例装置において使用されたCPU10の
処理を示すフローチャートである。CPU10はステッ
プ100から実行を開始し、8秤の初期設定を行う。次
にステップ102で画像入力信号回路7を駆動するため
の信号v3を出力する。画像入力信号回路アはラインカ
メラ6を駆動し、前述した様に映像信号v1を入力して
、それを2値化し、2111I化された一次元明on図
形として、画像メモリ8に記憶する。モータ駆動回路9
に制御信号v2を出力して、ネジ2を回転し、一次元明
暗図形を多くネジの外形線に対して入力し側面展開図形
を得る。cpuはステップ104で画像入力信号回路7
からの(を号を検出して、展開図の人力が完了されたか
をI’l+定する。入力が完了した場合には、次のステ
ップに移行してパターンの判定を(うなう。まず、ステ
ップ105 t−は、明部として表わされたネジ山の描
くネジ線を検出し、各部分におけるピッチを埠出する。
FIG. 8 is a flowchart showing the processing of the CPU 10 used in the apparatus of this embodiment. The CPU 10 starts execution from step 100 and initializes the eight scales. Next, in step 102, a signal v3 for driving the image input signal circuit 7 is output. The image input signal circuit A drives the line camera 6, inputs the video signal v1 as described above, binarizes it, and stores it in the image memory 8 as a 2111I one-dimensional bright on figure. Motor drive circuit 9
A control signal v2 is outputted to rotate the screw 2, and many one-dimensional bright and dark figures are inputted to the outline of the screw to obtain a side-developed figure. The CPU inputs the image input signal circuit 7 in step 104.
Detects the () symbol and determines whether the manual input of the developed diagram has been completed. If the input is complete, move on to the next step and judge the pattern (noun. First, Step 105 t- detects the thread line drawn by the thread represented as a bright part, and determines the pitch in each part.

この結果、ネジ線のピッ升の不良箇所が検出される。例
えば第7図にJゴいて、欠わ53があるところではピッ
チは通常ビッヂの2倍となっ−Cいる。また、変形した
欠陥54では、片方のピッチが大きく、片方のピッチが
小さくイ(つている。又、埃等が着いた欠陥55ではピ
ッチが小さくなっている。
As a result, a defective location in the pitch of the screw wire is detected. For example, in FIG. 7, where there is a notch 53, the pitch is twice as large as the normal pitch. Further, in the deformed defect 54, the pitch on one side is large and the pitch on the other side is small.Furthermore, in the defect 55 where dust or the like has adhered, the pitch is small.

次に、他の方法によって欠陥部分を抽出する。Next, the defective portion is extracted using another method.

以下の方法はネジ線の太さが変化するような欠陥も検出
することができる。即ち、ステップ106でネジ線の傾
斜角を測定する。この測定された傾斜角方向に沿って所
定間だけ、得られた展開図形を水平、垂直方向に移動さ
せる。次に、移動後の画面と、移動前の画面との間で排
他的論理和を求める。モの結果1qられた図形は、第9
図に示されている。即も、正常な部分は前記の一定の移
動に対して、移動前、移動後が同じパターンどなるため
に、その排泄的論理mにより、その部分は、′O″′と
なる。しかし欠陥部は周期性がないために、移動によっ
て図形が重ならない。従って欠陥部は、62.63.6
4で示すように、明らかに表われる。このような方法に
より不良部分のみを抽出することができる。又、ネジ線
の太さは量子化誤差等によりラインカメラの1ビット程
度の変動があるため65のようなノイズを生じるが、こ
のようなノイズや微小な欠陥は、フィルタ処理を施すこ
とにより除去できる。この様にして1qられた欠陥部分
の図形面積を所定の基準値と比較することにより、外観
の良否を的確に判定することができる。本実施例装置は
上記の溝成及び作用から成るものである。
The following method can also detect defects where the thickness of the thread line changes. That is, in step 106, the inclination angle of the thread line is measured. The obtained developed figure is moved in the horizontal and vertical directions for a predetermined distance along the direction of the measured inclination angle. Next, an exclusive OR is calculated between the screen after movement and the screen before movement. The result 1q is the 9th figure.
As shown in the figure. In other words, since a normal part has the same pattern before and after the movement for the above-mentioned constant movement, that part becomes 'O''' due to the excretory logic m.However, the defective part Since there is no periodicity, the figures do not overlap due to movement.Therefore, the defective part is 62.63.6
4, it is clearly visible. With this method, only defective parts can be extracted. In addition, the thickness of the screw wire fluctuates by about 1 bit of the line camera due to quantization errors, etc., resulting in noise such as 65, but such noise and minute defects can be removed by filtering. can. By comparing the graphic area of the defective portion thus calculated by 1q with a predetermined reference value, it is possible to accurately determine whether the appearance is good or bad. The device of this embodiment has the groove structure and operation described above.

上記実施例に貿は、欠陥部の抽出にネジ線の方向に沿っ
て画面を移動させ、排他的論理和を求めている。しかし
ネジ2のロータ3への配設によってはネジ2がロータ3
の回転軸から傾斜する場合がある。そのような場合には
、展開図形は第10図(a)に示・1−ようにネジ線が
曲線状に変形した乙のどなる。このためネジ線方向に沿
って、画面を移動さびることかできないつまた、移動さ
せてら曲率がそれぞれ異なっているために重ならない。
In the above embodiment, the screen is moved along the direction of the screw line to extract the defective part, and an exclusive OR is calculated. However, depending on the arrangement of screw 2 to rotor 3, screw 2 may be attached to rotor 3.
may be tilted from the axis of rotation. In such a case, the developed figure will be a curved shape with the screw line deformed into a curved shape as shown in FIG. 10(a). For this reason, the screen cannot be moved along the screw line direction, and the curvatures of the screens are different, so they do not overlap.

従つ−にれらが欠陥81の検出誤差となって表われる。Therefore, these appear as detection errors of the defect 81.

この問題を回避するために、次の手法が必要である。第
10図(b)に示すようにネジ線から一定m+隔でサン
プル点82を抽出し、サンプル点82を結ぶ腺どして折
線83でネジ線を近似する。
To avoid this problem, the following method is required. As shown in FIG. 10(b), sample points 82 are extracted from the thread line at constant m+ intervals, and the thread line is approximated by a broken line 83 connecting the sample points 82.

そして近似した折線が、移動後の対応領域の折線に重な
るよ゛)【こ3部の画像の移U量を求める。即ら、第1
0図(b)のX軸方向の移動量(よ、全てのアドレスに
、13いて一定であるが、Y軸方向の移動用を移動ずべ
き図形の×座標に応じて変化させるようにしている。そ
うすれば曲線状に変曲している画像にJ3いてら、規則
性のある部分を重ね合わVることがCさる。又、曲率が
Y座標によって異なる場合に(L、四にX座1グ及びY
座標に応じてY方向の移動用を変fヒさければ、完全な
一致が得られる。
Then, the approximate polygonal line overlaps the polygonal line of the corresponding area after movement.) [The amount of displacement of these three images is determined. That is, the first
The amount of movement in the X-axis direction in Figure 0 (b) is constant (13 for all addresses), but the amount of movement in the Y-axis direction is changed according to the x coordinate of the figure to be moved. If you do this, if you have J3 on an image that is inflected in a curved shape, you can superimpose regular parts on V.Also, if the curvature differs depending on the Y coordinate (L, 4, G and Y
If the movement in the Y direction is changed according to the coordinates, perfect matching can be obtained.

光の照射方法は、第11図に示すように光源1とネジ2
との間に散乱板71を配設してもよい。
The light irradiation method is as shown in Figure 11, using light source 1 and screw 2.
A scattering plate 71 may be provided between the two.

照明に発光ムラがある場合、ネジ以外の部分でラインカ
メラ方向に強く反射する面があり、ネジの画像に影響を
与える場合にイ1効である。
If there is uneven illumination, there are surfaces other than the screw that strongly reflect toward the line camera, which is particularly effective if the image of the screw is affected.

[発明の効果] 本発明は、ネジの側面展開図形を検出し、その側面展開
図形からネジの特徴を加味して、ネジの外観不良を検出
する方法及び装置である。側面展開図形図形を処理して
いるため、すべての周囲について、同じ精度で、欠陥部
を検出することができる。
[Effects of the Invention] The present invention provides a method and apparatus for detecting a side-view developed figure of a screw, and detecting a defective appearance of the screw by taking characteristics of the screw into consideration from the side-view developed figure. Since side development figures are processed, defective parts can be detected with the same accuracy in all surrounding areas.

本装置は、外観不良の検出を自動化しているので人間の
目視による検査に比較し、作業効率が向上すると共に、
検出精度が高い。
This device automates the detection of appearance defects, which improves work efficiency compared to human visual inspection.
High detection accuracy.

【図面の簡単な説明】[Brief explanation of the drawing]

第1図は本発明装置の概念を示したブロックダイアグラ
ムである。第2図は本発明装置の具体的な実施例に係る
検査装置の構成を示したブロックダイアグラムである。 第3図は照明装置から放射される光の照射角度及び、ネ
ジとそれからの反射光を検出するラインセンサの位置関
係を示した説明図、第4図はネジの外形、反射光によっ
てiqられる映像信号、それを処理した2値化信号及び
その2値化信弓から成る側面展開図形を示した説明図で
ある。第5図及び第6図は欠陥部がある場合のネジの外
形映像信号、2値化信号の波形を示した説明図、第7図
は検出された欠陥がある場合のネジの側面展開図を示し
た図である。第8図は同実施例装置において使用しlζ
計痺機の処理を示すフローヂV−ト、第9図は同装冒に
おいて排他的論理和をとることによって不良部分を抽出
した不良品抽出図形である。第10図は他の展開図形を
移動して重ね合わせる方法を説明する説明図であり、第
11図は他の照射方法を説明する説明図である。 特許出願人   日本電装株式会社 代理人    弁理士 大川 宏 同     弁理士 藤谷 修 同     弁理士 丸山明夫 2] 第4図(a)   第4図(b)第4図(C)第5図 2] (a)        (b)     (C)第6図 に量 (a)       (’b)    (C)第8図 第9図 $10図 y (a)          (b)   −ア第11図 に2 (a)
FIG. 1 is a block diagram showing the concept of the device of the present invention. FIG. 2 is a block diagram showing the configuration of an inspection device according to a specific embodiment of the present invention. Figure 3 is an explanatory diagram showing the irradiation angle of the light emitted from the lighting device and the positional relationship between the screw and the line sensor that detects the reflected light from it. Figure 4 is the outline of the screw and the image created by the reflected light. FIG. 2 is an explanatory diagram showing a side development figure consisting of a signal, a binary signal obtained by processing the signal, and a binary signal thereof. Figures 5 and 6 are explanatory diagrams showing the waveforms of the external image signal and binary signal of the screw when there is a defect, and Figure 7 is a side development view of the screw when there is a detected defect. FIG. Figure 8 shows lζ used in the same embodiment device.
FIG. 9, a flowchart showing the processing of the metering machine, is a defective product extraction figure in which defective parts are extracted by performing exclusive OR on the same packaging. FIG. 10 is an explanatory diagram illustrating a method of moving and overlapping another developed figure, and FIG. 11 is an explanatory diagram illustrating another irradiation method. Patent applicant Nippondenso Co., Ltd. Agent Patent attorney Hirodo Okawa Patent attorney Shudo Fujitani Patent attorney Akio Maruyama2] Figure 4 (a) Figure 4 (b) Figure 4 (C) Figure 5 2] (a ) (b) (C) Figure 6 shows the amount (a) ('b) (C) Figure 8 Figure 9 $10 Figure y (a) (b) -a Figure 11 shows the amount (a)

Claims (10)

【特許請求の範囲】[Claims] (1)ネジに特定方向から光を照射し、該ネジの側部に
置かれた映像センサによって、前記ネジからの反射光を
検出することにより該ネジの軸方向に沿った一次元の明
暗図形を検出し、 前記ネジと前記映像センサとの相対的回転により、前記
ネジの側面部の前記一次元明暗図形を、全周に渡り検出
することにより、前記ネジの側面展開図形を得て、該側
面展開図形から前記ネジの外観不良を検査する検査方法
(1) A one-dimensional light-dark figure along the axial direction of the screw is created by irradiating light onto the screw from a specific direction and detecting the reflected light from the screw using a video sensor placed on the side of the screw. , and detecting the one-dimensional light-dark figure on the side surface of the screw over the entire circumference by the relative rotation between the screw and the video sensor, thereby obtaining a side development figure of the screw; An inspection method for inspecting external appearance defects of the screw from a side development figure.
(2)前記側面展開図形は、明暗レベルに応じて、2値
化されており、前記ネジの外観不良の判定は、前記2値
化された側面展開図形に表われた、パターンの周期性の
良否により行なうことを特徴とする特許請求の範囲第1
項記載のネジの外観不良検査方法。
(2) The side development figure is binarized according to the brightness level, and the determination of the appearance defect of the screw is based on the periodicity of the pattern appearing in the binarized side development figure. Claim 1 characterized in that it is determined based on quality.
Method for inspecting external appearance defects of screws as described in section.
(3)前記側面展開図形は、明暗レベルに応じて2値化
されており、前記ネジの外観不良の判定は、前記2値化
された側面展開図形を、その上に表われたネジ線に沿っ
て所定量移動し、移動前の側面展開図形との排他的論理
和をとることにより不良部を抽出した図形を求め、該図
形に基づいて行なうことを特徴とする特許請求の範囲第
1項記載のネジの外観不良の検査方法。
(3) The side development figure is binarized according to the brightness level, and the judgment of the appearance defect of the screw is made by converting the binarized side development figure to the screw line appearing on it. Claim 1, characterized in that the process is carried out based on a figure in which a defective part is extracted by moving a predetermined amount along the same direction and performing an exclusive OR with the side development figure before the movement, and extracting the defective part. Method for inspecting the appearance defects of the described screws.
(4)前記側面展開図形は、明暗レベルに応じて2値化
されており、前記2値化された側面展開図形を、前記ネ
ジの軸方向及びそれに垂直な軸方向へ単位量移動させて
移動図形を求めるに当り、前記軸方向の移動量を、ネジ
線の各部の傾斜に応じて変化させており、移動前後の側
面展開図形の排他的論理和をとることにより、不良部を
抽出した図形を求め、該図形に基づいて、前記ネジの外
観不良の検査を行なうことを特徴とする特許請求の範囲
第1項記載の検査方法。
(4) The side developed figure is binarized according to the brightness level, and the binarized side developed figure is moved by moving a unit amount in the axial direction of the screw and in the axial direction perpendicular thereto. To obtain the figure, the amount of movement in the axial direction is changed according to the inclination of each part of the screw line, and by taking the exclusive OR of the side development figures before and after the movement, the defective part is extracted. 2. The inspection method according to claim 1, wherein the screw is inspected for defects in appearance based on the figure.
(5)前記光線を照射する特定方向は、前記ネジ山の先
端部からの光の反射が大きくなる様に、前記ネジの軸に
対し、やや傾斜した方向であることを特徴とする特許請
求の範囲第1項記載のネジの外観不良の検査方法。
(5) The specific direction in which the light beam is irradiated is a direction slightly inclined with respect to the axis of the screw so that the reflection of light from the tip of the screw thread is increased. A method for inspecting external appearance defects of screws as described in Scope 1.
(6)ネジに特定方向から光を照射する照明装置と、 該ネジからの反射光を検出することにより、該ネジの軸
方向に沿った一次元の明暗図形を検出する映像センサと
、 前記ネジを保持し、前記ネジと前記映像センサとの相対
的回転を制御する回転制御装置と、前記回転制御装置を
駆動し、前記ネジの側面部の前記一次元明暗図形をネジ
の全周に渡り検出して明暗レベルに応じて2値化した側
面展開図形を得る側面展開図形検出装置と、 前記側面展開図形検出装置によって検出された2値化さ
れた側面展開図形を処理し、前記ネジの外観の良否を判
定するパターン判定装置と、から成るネジの外観不良検
査装置。
(6) a lighting device that irradiates light onto the screw from a specific direction; an image sensor that detects a one-dimensional bright and dark pattern along the axial direction of the screw by detecting reflected light from the screw; and the screw. a rotation control device that holds the screw and controls relative rotation between the screw and the image sensor; and a rotation control device that drives the rotation control device to detect the one-dimensional brightness pattern on the side surface of the screw over the entire circumference of the screw. a side development figure detection device that obtains a binarized side development figure according to the brightness level; and a side development figure detection device that processes the binarized side development figure detected by the side development figure detection device to determine the appearance of the screw. A screw appearance defect inspection device comprising a pattern determination device for determining quality.
(7)前記パターン判定装置は、2値化された側面展開
図形に表われたパターンの周期性の良否により外観の良
否判定を行なうことを特徴とする特許請求の範囲第6項
記載のネジの外観不良の検査装置。
(7) The pattern determining device determines whether the appearance of the screw is good or bad based on whether the periodicity of the pattern appearing in the binarized side development figure is good or bad. Inspection device for defective appearance.
(8)前記パターン判定装置は、前記2値化された側面
展開図形を、その上に表われたネジ線に沿って所定量移
動し、移動前の側面展開図形との排他的論理和をとるこ
とにより不良部を抽出した図形を求め、該図形に基づい
て外観の良否判定を行なうことを特徴とする特許請求の
範囲第6項記載のネジの外観不良検査装置。
(8) The pattern determination device moves the binarized side developed figure by a predetermined amount along the screw line appearing thereon, and calculates an exclusive OR with the side developed figure before movement. 7. The apparatus for inspecting external appearance defects of screws according to claim 6, wherein a figure is obtained by extracting a defective part, and the quality of the appearance is determined based on the figure.
(9)前記パターン判定装置は、前記2値化された側面
展開図形を、前記ネジの軸方向及びそれに垂直な軸方向
へ単位量移動させて移動図形を求めるに当り、前記軸方
向の移動量を、ネジ線の各部の傾斜に応じて変化させて
おり、移動前後の側面展開図形の排他的論理和をとるこ
とにより、不良部を抽出した図形を求め、該図形に基づ
いて、前記ネジの外観不良の判定を行なうことを特徴と
する特許請求の範囲第6項記載のネジの外観不良検査装
置。
(9) In moving the binarized side developed figure by a unit amount in the axial direction of the screw and in an axial direction perpendicular thereto to obtain a moving figure, the pattern determination device may move the binarized side developed figure by the amount of movement in the axial direction. is changed according to the inclination of each part of the screw line, and by taking the exclusive OR of the side development figures before and after movement, a figure that extracts the defective part is obtained, and based on this figure, the screw 7. The screw appearance defect inspection device according to claim 6, wherein the screw appearance defect inspection device determines appearance defects.
(10)前記照明装置による前記光線を照射する特定方
向は、前記ネジのネジ山の先端部からの光の反射が大き
くなる様に、前記ネジの軸に対し、やや傾斜した方向で
あることを特徴とする特許請求の範囲第6項記載のネジ
の外観不良の検査装置。
(10) The specific direction in which the light beam is irradiated by the illumination device is a direction slightly inclined with respect to the axis of the screw so that the reflection of light from the tip of the thread of the screw is large. An apparatus for inspecting external appearance defects of screws according to claim 6.
JP19908384A 1984-09-21 1984-09-21 Method and device for inspecting appearance failure of screw Granted JPS6176941A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP19908384A JPS6176941A (en) 1984-09-21 1984-09-21 Method and device for inspecting appearance failure of screw

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP19908384A JPS6176941A (en) 1984-09-21 1984-09-21 Method and device for inspecting appearance failure of screw

Publications (2)

Publication Number Publication Date
JPS6176941A true JPS6176941A (en) 1986-04-19
JPH0535379B2 JPH0535379B2 (en) 1993-05-26

Family

ID=16401815

Family Applications (1)

Application Number Title Priority Date Filing Date
JP19908384A Granted JPS6176941A (en) 1984-09-21 1984-09-21 Method and device for inspecting appearance failure of screw

Country Status (1)

Country Link
JP (1) JPS6176941A (en)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61256237A (en) * 1985-05-09 1986-11-13 Dainippon Printing Co Ltd Defect inspection for cyclic pattern
JPH06307829A (en) * 1993-04-26 1994-11-04 Nippondenso Co Ltd Screw defect inspection device
JP2008185462A (en) * 2007-01-30 2008-08-14 Toyota Motor Corp Method and apparatus for judging quality of screw
JP2008224523A (en) * 2007-03-14 2008-09-25 Denso Corp Inspection device and inspection method of screw component
JP2010038555A (en) * 2008-07-31 2010-02-18 Jfe Steel Corp Setting device of circumferential direction start position in oil well pipe screw-thread shape perimeter measurement
JP2011145182A (en) * 2010-01-15 2011-07-28 Ushio Inc Inspection device of screw thread
JP2012063268A (en) * 2010-09-16 2012-03-29 Honda Motor Co Ltd Workpiece inspection apparatus and workpiece inspection method
JP2012251931A (en) * 2011-06-06 2012-12-20 Kurabo Ind Ltd Bottle-can screw-portion inspection device
US8723946B2 (en) 2010-09-16 2014-05-13 Honda Motor Co., Ltd. Workpiece inspecting apparatus and workpiece inspecting method
US20150241303A1 (en) * 2014-02-26 2015-08-27 Siemens Energy, Inc. Method for inspecting a turbine engine rotor with a thru bolt threads inspection apparatus
JP2018036172A (en) * 2016-09-01 2018-03-08 富士フイルム株式会社 Inspection device and method

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS53102685U (en) * 1977-01-25 1978-08-18
JPS54150163A (en) * 1978-05-17 1979-11-26 Nippon Kokan Tsugite Kk Automatic tester for screw member
JPS55160838A (en) * 1979-06-01 1980-12-15 Hiyuutec:Kk Method for detecting surface of round bar

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS53102685U (en) * 1977-01-25 1978-08-18
JPS54150163A (en) * 1978-05-17 1979-11-26 Nippon Kokan Tsugite Kk Automatic tester for screw member
JPS55160838A (en) * 1979-06-01 1980-12-15 Hiyuutec:Kk Method for detecting surface of round bar

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61256237A (en) * 1985-05-09 1986-11-13 Dainippon Printing Co Ltd Defect inspection for cyclic pattern
JPH06307829A (en) * 1993-04-26 1994-11-04 Nippondenso Co Ltd Screw defect inspection device
JP2008185462A (en) * 2007-01-30 2008-08-14 Toyota Motor Corp Method and apparatus for judging quality of screw
JP2008224523A (en) * 2007-03-14 2008-09-25 Denso Corp Inspection device and inspection method of screw component
JP2010038555A (en) * 2008-07-31 2010-02-18 Jfe Steel Corp Setting device of circumferential direction start position in oil well pipe screw-thread shape perimeter measurement
JP2011145182A (en) * 2010-01-15 2011-07-28 Ushio Inc Inspection device of screw thread
JP2012063268A (en) * 2010-09-16 2012-03-29 Honda Motor Co Ltd Workpiece inspection apparatus and workpiece inspection method
US8723946B2 (en) 2010-09-16 2014-05-13 Honda Motor Co., Ltd. Workpiece inspecting apparatus and workpiece inspecting method
JP2012251931A (en) * 2011-06-06 2012-12-20 Kurabo Ind Ltd Bottle-can screw-portion inspection device
US20150241303A1 (en) * 2014-02-26 2015-08-27 Siemens Energy, Inc. Method for inspecting a turbine engine rotor with a thru bolt threads inspection apparatus
US9494487B2 (en) * 2014-02-26 2016-11-15 Siemens Energy, Inc. Method for inspecting a turbine engine rotor with a thru bolt threads inspection apparatus
JP2018036172A (en) * 2016-09-01 2018-03-08 富士フイルム株式会社 Inspection device and method

Also Published As

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