JPH0719819A - Covered wire peeling inspection device - Google Patents

Abstract

(57) [Summary] [Purpose] A sensor incorporated in a peeling machine that strips off the end coating of a coated electric wire and detects defective peeling of the tip of the covered electric wire that moves at high speed while vibrating immediately after peeling. As a result, even if there is a change in the passing position of the peeling boundary portion, the light shielding length can always be detected near the peeling boundary portion, and the complicated and difficult adjustment of the above optical sensor is eliminated. To do. [Structure] The passage of the coated electric wire that is stripped and moving at high speed,
An optical sensor for synchronous detection detects and opens the electronic shutter at high speed, and a two-dimensional CCD sensor photographs the peeled part,
A binarized image with that shadow is obtained. For this image data, the step S is detected by peeling, and the length of the shadow portion is measured on two straight lines having coordinate values obtained by adding and subtracting a predetermined set width w to the step coordinates. Further, the measured length ratio (L _a / L _b ) is compared with a reference range corresponding to the line type, and good or bad of peeling is determined and output.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a peeling inspection apparatus for a coated electric wire, which is incorporated in a peeling machine for peeling off the coating of an end portion while feeding the covered electric wire at a high speed to judge the quality of the peeled electric wire.

[0002]

2. Description of the Related Art As shown in FIG. 6, an automatic machine for stripping the coating 2 on both ends of a coated electric wire 1 and crimping a crimping terminal 4 to a core wire 3 employs work steps shown in FIGS. To do.

In FIG. 7, there is a cutting / stripping position A in the middle of a straight path of a covered electric wire, and on the left and right sides thereof, crimping positions B and C of crimp terminals for one end and the other end. The covered electric wire 1 is supplied in a long state from the right side in the figure, and is cut and peeled at the cutting / peeling position A. Although not shown in the drawing, at the same time as cutting with a cutting cutter to a predetermined size, the stripping cutter grips the stripped portion and pulls the slider that clamps the covered electric wire to strip the end portion. The stripped covered electric wire 1 is clamped by the clamper 5 and is fed at high speed to the left and right caulking stop positions B and C by the arm rotation as shown in FIG. 8, and is crimped to the core wire 3 protruding by the peeling. The terminal 4 is crimped by a press machine.

When the automatic stripping machine for coated electric wires is used, as shown in FIG. 9, (a) coating remains, (b) part of the core wire is cut off too much, and (c) core wire is also cut. Poor peeling such as cutting off may occur.

When such a peeling defect occurs,
Since the crimp terminal cannot be fixed in a normal state,
Immediately after skinning, it is necessary to detect defects and eliminate defective products from the processing line to eliminate wasteful processing and prevent the occurrence of defective products.

Conventionally, as a sensor for detecting such a peeling defect, there has been an electric contact type sensor. this is,
The tip of the covered electric wire sent from the peeling process to the crimping prevention process of the crimping terminal is passed between the opposed spring-type electric contacts, and a defect is detected by the presence or absence of a short circuit of the electric contacts due to the core wire.

However, in this electric contact method, the electric wire moves at a high speed so that the contact is unstable, and since the electric wire is brought into contact with the core wire 3 which is moving at a high speed, the core wire 3 is apt to be damaged and bent.

Therefore, a sensor for a covered electric wire, which uses an optical sensor to detect a defect in a non-contact manner, has been used (Japanese Patent Laid-Open No. Sho 5).
9-12313 and JP-A-63-229379).

In these devices, an optical sensor in which a light emitter and a light receiver are opposed to each other is provided in the movement path of the electric wire immediately after peeling, and the light shielding time when the covered electric wire 1 crosses the optical sensor is measured, The quality of peeling is judged.

In the invention of the former publication, the light-shielding time of the core portion is measured by a pair of the light emitter and the light receiver, but in the invention of the latter publication, two pairs of the light emitter 6 and the light receiver 7 are used as shown in FIG.
The used light-shielding time t _a of the peeling has been the core portion and peeling are not part of t _b is measured separately at the same time, are performed yo defect determination by comparing these shading time.

[0011]

Since the peeling defect detector using the above-mentioned optical sensor is a non-contact type, it eliminates the above-mentioned drawbacks of the defect detector using a spring type electric contact.

However, in practical use,
The following problems remained.

The defect detector using the above-mentioned optical sensor, which uses two pairs of the light emitter and the light receiver, eliminates the error due to the temperature drift and the fluctuation of the passing speed when the pair of the light emitter and the light receiver is used. It is presumed that this is not the case (not described in the publication), and in this respect, two pairs of inventions are more advanced inventions.

As shown in FIG. 10, when the light-shielding time of the stripped core wire portion and the light-shielding time of the non-peeled portion are separately measured by the two pairs of the projector 6 and the light receiver 7, ideally, it is shown in FIG. As shown in FIG.
And the detection position P of the light receiver 7 is preferable.
This is because when the core wire 3 is a stranded wire, the tip is likely to spread after cutting as shown in the figure, and even if the core wire 3 is normally peeled, it may be erroneously determined to be defective.

However, in the actual detection of defective peeling, the boundary line 8 does not always pass through a fixed position with respect to the optical sensor, and is indicated by a chain line in FIG. 11 when viewed from the light emitter and the light receiver. As shown, it passes through a position displaced indefinitely. This is due to the following two reasons.

That is, since the peeling process is carried out by pressing the other with a peeling cutter and pulling the other, the boundary position of peeling is unstable due to expansion and contraction of the coating 2, slipping of the clamper, etc. And, the peeling defect is detected during the high speed movement from the cutting / peeling position A to the crimping stop positions B and C (for example, 2 m / sec), and the clamped covered electric wire 1 vibrates violently, and the posture and position are That is, the detection is performed in an unstable state.

Therefore, the mounting positions of the two pairs of the light-emitter 6 and the light-receiver 7 need to be set at positions far apart from each other as shown by P'in FIG.

For this reason, there is a drawback that an erroneous determination is made when the core wire 3 is a stranded wire and the tip is widened. Even if it is installed with a further margin, if the adjustment of the mounting position is difficult and the passage position of the peeling boundary 8 has a large variation, if the adjustment is improper, the wire will not have the tip of the core wire widened. May be erroneously determined. In addition,
This adjustment work is a manual work of moving the optical sensor little by little while looking at the passing electric wires, and it is necessary to perform it whenever the type of wire to be processed changes.

Therefore, according to the present invention, even if there is a change in the passing position, the light-shielding length can always be detected near the boundary portion of the peeling, and the peeling removing the complexity and difficulty of the above-mentioned optical sensor mounting adjustment is eliminated. An object is to provide an inspection device.

[0020]

SUMMARY OF THE INVENTION The present invention provides a peeling inspection device incorporated in a peeling machine for stripping the end coating of a coated electric wire. It has an electronic shutter that opens when the sensor detects the wire, and takes an image of the wire end 2
A sensor unit provided with a three-dimensional CCD sensor, which is gripped by a clamper after stripping and is installed at a passing position of an end of an electric wire which is moving at high speed;

A binarization circuit that binarizes the output of the two-dimensional CCD sensor and distinguishes the shadowed wire end from the other part, a still image memory that stores the binarized data, and the stored image. Step detection processing for detecting the coordinates of the step of the peeled portion and the non-peeled portion with respect to the binarized data with respect to a predetermined coordinate axis, adding a predetermined set value to the detected coordinate value of the step, and Find the length of the shadow part on the two straight lines with the coordinate values obtained by subtraction, and measure the length of the peeled part and the non-peeled part, the ratio of the measured length It is characterized in that it has a judging section for comparing the judgment value with a judgment value and performing a judgment processing for generating a judgment output.

[0022]

In the above structure, when the tip of the stripped covered electric wire enters the detection area of the sensor section, the synchronous detection sensor detects it and opens the electronic shutter at high speed. As a result, the two-dimensional CCD sensor photographs the stripped portion of the covered electric wire.

This image data is a binarization circuit and is shown in FIG.
As shown in (4), it is taken into the still image memory as binarized data divided into a shaded portion d due to the covered electric wire and a non-shaded portion b.

The determination circuit detects the position of the step S (for example, the x-axis coordinate x _s ) in the binarized image data, and adds and subtracts a predetermined set width w from the detected coordinate. Measure the shadow part on two straight lines having the values (x _s −w, x _s + w).

Then, the ratio (L _a / L _b ) is compared with a reference range set in advance corresponding to the line type, and good or bad of peeling is judged and output.

[0026]

1 is a block diagram showing the overall construction of a peeling inspection apparatus 10 of the present invention.

As shown in FIG. 8, reference numeral 11 designates a sensor portion which is held by the clamper 5 after peeling and is installed at the passing position of the end portion of the covered electric wire 1 which is moving at high speed.
2. Two-dimensional CCD sensor 1 for taking an image of the end of the wire
It has a binarization circuit 15 for binarizing the output of the 4- and 2-dimensional CCD sensor. The two-dimensional CCD sensor 14 includes an electronic shutter 13 that opens for a predetermined time when the synchronization detection sensor 12 detects an electric wire.

A transmission type photoelectric switch is used as the synchronization detection sensor 12, and the projector 12a and the light receiver 12b thereof are
The detection recess 1 of the U-shaped sensor unit case 16 shown in FIG.
It is attached so as to face both sides of 7. Further, as the light receiving circuit which determines the presence or absence of the covered electric wire 1 based on the presence or absence of light reception, a light receiving circuit that operates at high speed with a response time of, for example, about 20 μsec is used.

As the electronic shutter 13 included in the two-dimensional CCD sensor 14, for example, an electronic shutter 13 capable of high-speed operation of about 64 μsec is used, and as shown in FIG. Mounted.

The two-dimensional CCD sensor 14 is, for example, one in which photodiodes are two-dimensionally arranged so that the voltage output by each photodiode according to the amount of received light can be individually and sequentially taken out. In the detection concave portion 17, a light source such as a light emitting diode is used as a light source 18a inside the surface opposite to the surface on which the two-dimensional CCD sensor 14 is attached, and the lens system 1 is used.
A collimated light irradiation unit 18 for obtaining collimated light by 8b is incorporated. The passing space of this parallel light is the detection area shown in FIG.

Further, as shown in FIG. 3C, a backlight illumination 18 'using a large number of light sources 18a' and a diffuser plate 25 '.
As a result, the same effect can be obtained in an optical system in which the covered electric wire 1 is imaged by the lens 26. In this case, if the distance between the imaging lens 26 and the covered electric wire 1 changes, the image becomes blurred and becomes unclear, or the magnification changes and the true electric wire diameter cannot be determined.

However, this device is not compatible with the covered electric wire 1 and the two-dimensional CC.
Since the D sensor 14 is mechanically fixed (the covered electric wire 1 is gripped by the clamper 5 and passes through the fixed position in the optical axis direction), the image is not blurred and detection is not difficult. Further, even if the detection position changes and the image magnification changes, the quality is determined by the relative comparison between the covering portion and the core portion, so that the detection accuracy is not affected.

The binarization level of the binarization circuit 15 can be adjusted to an optimum value according to the brightness of the surroundings and the like.

Returning to FIG. 1, 19 is the binarization circuit 15 described above.
A still image memory for storing the binarized data output from the device, and 20 is a determination unit that performs data processing described below on the stored binarized data to determine pass / fail. 21
Is a monitor television for adjusting the mounting position of the sensor unit 11 and the like, and displays the stored still image together with the detected position of the step currently being processed and the two straight lines to be measured. 22
Is a control unit that manages the data transfer of the entire device and the timing of operation / processing. An operation panel 23 has a function of setting / selecting a judgment value according to a line type and a function of displaying various data such as coordinates of steps and coordinates of two straight lines for length measurement.

As shown in FIG. 7, when detecting at two points B and C on both ends of the electric wire as shown in FIG. 7, the sensor section 11 has two pairs as shown in FIG. Therefore, the determination section 20 and the like need only be set once, and the controller 24 of FIG. 2 incorporating these sets is shared.

Next, the operation of the peeling inspection apparatus 10 of the present invention will be described together with the processing of the judging section 20.

The tip of the stripped covered electric wire 1 is gripped by the clamper 5, and the detection recess 17 of the sensor case 16 is held.
When passing through, the synchronization detection sensor 12 detects the light shielding state at high speed and opens the electronic shutter 13 for a predetermined time. As a result, a still image having the covered electric wire 1 as a shadow portion is captured, binarized by the binarizing circuit 15, and stored in the still image memory 19. This image data is displayed on the monitor television 21 as a bright and dark image shown in FIG.

When the binarized data is stored in the still image memory 19, the control unit 22 causes the determination unit 20 to execute the processing as shown in FIG. This processing is image data processing using a microcomputer.

First, the step point (S in FIG. 4) between the peeled portion and the non-peeled portion is detected. This is to follow the Y coordinate of the edge of the shadow along the axial coordinate of the covered electric wire (referred to as the X axis), and when the coordinate value suddenly changes, obtain the X coordinate as the coordinate of the step point. Is. If the step point S is not detected at this time, the step shown in FIG.
It is judged that the coating remains in (a) or the cut-off in (c) of the figure is made, and an NG signal is generated, and the processing is terminated.

When the coordinates of the step point S are obtained, coordinate values (x _s −w, x _s) obtained by adding and subtracting a predetermined set width w to / from this step.
+ W) is calculated. As shown in FIG. 4, this set width w is a length that reliably separates the peeled portion and the non-peeled portion even if the covered electric wire 1 is photographed with a slight inclination. Set to This is, for example, 0.5 mm in actual size.

Next, the length of the shaded portion corresponding to the covered electric wire 1 on the two straight lines having the coordinate values (x _s -w, x _s + w) and parallel to the Y axis (L in FIG. 4). _a / L _b ) is measured.

Then, this length ratio (L _a / L _b ) is compared with a reference range preset corresponding to the line type,
If it is within this range, an OK signal is output, and if it is outside this range, an NG signal is output, and the processing ends.

Here, the reference range corresponding to the wire type refers to the ratio of the diameter of the electric wire including the coating determined according to the wire type and the diameter of the core wire (generally 0.44 to 0.78) of the device of the present invention. A user or the like sets a predetermined vertical width as an error range.

This judgment output is output to the peeling machine as a wire discharge signal, and the operation panel 234 displays OK or NG. In addition, on the operation panel 23, in addition to these, the coordinates of the step point, the length of the shadow portion and the ratio thereof (L _a / L _b ),
The reference range, etc., is displayed in numbers, making it easy to investigate the cause of defects when they occur.

Further, as shown in FIG. 4, the monitor TV 21 displays the still image currently being photographed together with the detected step point and the two straight lines for length measurement, so that it is easy to confirm the normal operation. is there. The monitor TV 21 is also used for adjusting the mounting position of the sensor unit 11. However, this is a simple one that only checks whether or not the tip of the insulated wire is projected on the monitor TV. However, the positioning accuracy may be extremely rough as compared with the delicate position adjustment of the two pairs of optical sensors which is the conventional example, and the work while looking at the monitor is much easier than the case of the eye register.

[0046]

The peeling inspection apparatus of the present invention is a two-dimensional C
By taking a high-speed image with a CD sensor, the vibrating covered electric wire is captured as a binary still image, and two straight lines that measure the light-shielding length are automatically set near the boundary of peeling, so high-speed movement is possible. With respect to the coated electric wire inside, even if the passing position of the boundary portion of the peeling changes, optimum measurement can be surely performed. This prevents misjudgment even when the core wire is a twisted wire and the tip is widened, and the maintenance is extremely simplified without the need for delicate position adjustment as in the case of using two pairs of optical sensors.

Further, since the quality is judged based on the ratio of the peeled portion and the non-peeled portion, there is no influence even if the covered electric wire which is passing through is tilted and the measuring length is changed. Can be determined.

Therefore, it is possible to provide a sensor most suitable for practical use as a sensor for detecting defective peeling immediately after the peeling process in the peeling machine for the covered electric wire.

[Brief description of drawings]

FIG. 1 is a block diagram showing the overall configuration of the present invention.

FIG. 2 is a perspective view showing the appearance of an embodiment of the present invention.

FIG. 3 shows a structural example of a sensor unit having the configuration of FIG.
(a) and (b) are a side view of one embodiment and a front view of a detection surface,
(c) is a side view of another embodiment.

FIG. 4 is a diagram showing a still image binarized by the present invention.

FIG. 5 is a flowchart showing the processing contents of the determination unit of the present invention.

FIG. 6 is a diagram sequentially showing a process of peeling the coated electric wire and crimping the crimp terminal.

FIG. 7 is a plan view showing a processing procedure of a peeling machine for performing the processing shown in FIG.

8 is a side view of the device of FIG.

FIG. 9 is a diagram showing a specific example of defective peeling.

FIG. 10 is a front view illustrating the operation principle of a conventional peeling inspection device using two pairs of optical sensors.

FIG. 11 is a relational diagram between a covered electric wire and detection points P and P ′ for explaining the problems of the peeling inspection apparatus shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Coated electric wire 2 Insulation coating 3 Core wire 5 Clamper 8 Border of peeling 10 Coated wire peeling inspection device 11 Sensor unit 12 Synchronous detection sensor 13 Electronic shutter 14 Two-dimensional CCD sensor 15 Binarization circuit 17 Detection recess 18, 18 ′ Irradiation unit (backlight illumination) 19 Still image memory 20 Judgment unit 21 Monitor TV 22 Control unit 23 Operation panel S Step point

Claims (1)

[Claims] 1. A peeling inspection device incorporated in a peeling machine for peeling off an end coating of a coated electric wire, comprising: a synchronous detection sensor composed of a photoelectric switch; and an electronic shutter when the synchronous detection sensor detects the electric wire. It has a two-dimensional CCD sensor that opens and captures an image of the end of the wire, and the sensor part that is gripped by the clamper after stripping and installed at the passage position of the end of the wire during high speed movement, and the output of the two-dimensional CCD sensor Binarizing circuit to distinguish the end of the wire from the shadowed wire and the other part, a still image memory to store the binarized data, and peel the stored binarized data. Step detection processing that detects the coordinates of the step between the portion and the non-skinned portion with respect to a predetermined coordinate axis, and has a coordinate value obtained by adding and subtracting a predetermined set value to the detected coordinate value of the step Shadow part on two straight lines Determine the length, measure the length of the peeled part and the non-peeled part, compare the ratio of the measured length with the judgment value, and perform the pass / fail judgment process to generate the pass / fail judgment output. A stripped inspection device for a covered electric wire having a portion.