JPH06225423A - Device for inspecting stripped end of electric wire - Google Patents

Abstract

PURPOSE:To provide an inspecting device, which can detect the quality of stripping simply and accurately in response to the output change of a light receiving part when the end part of an electric wire is made to pass in a light path from a light emitting part to the light receiving part by providing the light emitting part and the light receiving part. CONSTITUTION:A semiconductor laser is used for a light emitting device 12. A slit 14 is formed in a light receiving device 13. Light can be received through the slit 14. The end part of an electric wire to be inspected is moved in the direction perpendicular to the length direction of the slit 14. At this time, the change in amount of the received light is detected. A detected voltage VD, which is proportional to the amount of the received light, is formed between a first reference value VH and a second reference value VL. When the time between the values is outputted during the period of a counted value A, it is judged that the stripping is excellent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for inspecting whether or not a peeling process for peeling a coating on an end portion of an electric wire to expose a core wire of the end portion of the electric wire has been appropriately performed.

[0002]

2. Description of the Related Art In the manufacture of a wire harness composed of a large number of electric wires and the like, a peeling process is carried out to expose the core wires of the electric wire ends by removing the coating of the electric wire end portions. After that, the terminal fitting is crimped. That is, as shown in FIG. 6, a cut is made in the coating on the end of the electric wire W (see FIG.
(A)), the coating S on the end of the electric wire W is removed, and the electric wire W
The core wire C at the end of is exposed (FIG. 6B). Then, the terminal fitting T is crimped to the end portion of the electric wire W (see FIG. 6).
(C)).

In this case, when the peeling process is appropriately performed, the end of the electric wire W becomes as shown in FIG. 7 (a). That is, only the coating on the end of the wire W is removed cleanly,
The core wire C is not cut or chipped. However, if the peeling process is not performed properly, for example, as shown in FIG.
As shown in FIG. 7B, the coating S at the end of the electric wire W is not peeled off, or not only the coating at the end of the electric wire W but also the core wire is cut off as shown in FIG. 7C. 7
As shown in (d) or (e), the core wire C at the end of the electric wire W
Nearly half or most of them are missing. In the state where the end portion of the stripped electric wire W is shown in FIGS. 7B to 7E, even if the terminal fitting is crimped thereto, proper conduction between the terminal fitting and the electric wire W may not be obtained. However, there is a drawback that the terminal fittings are easily removed.

Therefore, conventionally, various inspection apparatuses have been proposed for inspecting whether or not the end portion of the electric wire has been properly stripped. For example, Japanese Utility Model Publication No. 4-5024 discloses an electric wire coating stripping failure detection device using a contact plate that mechanically contacts an end portion of an electric wire. Further, Japanese Patent Laid-Open No. 60-96117 also discloses a device for inspecting the stripping of an electric wire by a large number of contacts that make mechanical contact with the end of the electric wire.

As described above, various devices for optically inspecting the stripped state of the electric wire end without optically contacting it with a mechanical contact plate or the like have been proposed. . For example, Japanese Patent Application Laid-Open No. 57-198850 discloses a method of inspecting the quality of the insulation coating peeling state of an electric wire using a semiconductor image sensor.

Further, Japanese Patent Laid-Open No. 59-123413 has a light emitting device and a light receiving device, and the end of the wire is processed by passing the end of the wire through the optical path from the light emitting device to the light receiving device. A device for detecting a defect in a strip electric wire is disclosed. Further, JP-A-61-1544
Japanese Unexamined Patent Application Publication No. 12 also discloses a configuration in which a processed state of an end portion of an electric wire is inspected by using a diffusion type reflection type photoelectric switch.

Such a semiconductor image sensor, a pair of a light emitter and a light receiver, and a device for optically inspecting the processing state of the wire end using a diffuse reflection type photoelectric switch are mechanically attached to the wire end. Since no force is applied and the end portion of the wire is not bent by inspection, it is preferable as a detection device.

[0008]

Among the above-mentioned conventional optical inspection devices for inspecting the peeled state of the wire end, the one using a semiconductor image sensor is an apparatus because the semiconductor image sensor is expensive. The price is high,
There is a drawback that the structure of the signal processing circuit becomes complicated.

On the other hand, in the case of using a pair of a light emitter and a light receiver or using one diffuse reflection type photoelectric switch,
There is an advantage that the device can be configured with a simple configuration and at a relatively low cost. However, these devices have other drawbacks as follows. That is, in the conventional device for inspecting the peeling condition of the wire end using the pair of the light emitter and the light receiver, when passing the wire end to be inspected in the light path from the light emitter to the light receiver, There is a drawback that the passing position must be set strictly. This is because, for example, when an LED is used as the light emitter, the light emitted from the LED diverges, and the light spreads as the distance from the LED increases. Therefore, referring to FIG. 8, the wire end WE passing through the optical path from the light emitter 1 to the light receiver 2 will be described.
However, there is a difference in the change in the amount of light received by the light receiver 2 between the case where the light passes through the position of A1 and the case where the light passes through the position of A2. That is, when the wire end WE passes through the position A1, the amount of light blocked by the wire end WE is large,
Therefore, the change in the amount of light received by the light receiver 2 becomes relatively large. On the other hand, when the light passes through the position A2, the amount of light blocked by the wire end WE is relatively small, and therefore the light receiver 2
The change in the amount of light received by is relatively small. Therefore, when inspecting whether or not the wire end portion WE is appropriately stripped based on the change in the amount of light received by the light receiver 2, an error may occur in the inspection result.

On the other hand, a semiconductor laser is known as a light emitter for emitting parallel light that does not diverge. Since the light output from the semiconductor laser is parallel light, there is no divergence of the light as described with reference to FIG. 8 above, and due to the straightness of the light, the passing position of the wire end WE to be inspected is A1. Or A2 does not affect the change in the amount of light received by the light receiver 2.

Therefore, the inventor of the present invention uses a semiconductor laser that outputs parallel light to a light emitting portion in an inspection device for inspecting the peeling processing state of a wire end in a non-contact manner using a light emitting device and a light receiving device, A device for inspecting the stripping processing of the end of the wire that devises the shape of the light receiving window through which the light from the light receiving section is incident and that can easily and accurately detect the quality of the stripping processing based on the output change of the light receiving section. Invented

[0012]

The invention according to claim 1 is
A peeling processing inspection device in which a light emitting part and a light receiving part are arranged to face each other at a predetermined interval, light is emitted from the light emitting part toward the light receiving part, and the end of an electric wire to be inspected in the optical path is passed through. The section uses a semiconductor laser that emits parallel light or a member equivalent to it, and the light receiving section is provided with a slit so that only a predetermined range of light emitted from the light emitting section can be received. Is formed in a direction in which its longitudinal direction intersects with the end of the electric wire to be inspected. When the stored storage means, the signal output from the signal output means and the comparison reference value stored in the storage means are compared, and the comparison result of the comparison means is in a predetermined matching state, the wire end is stripped. Processing is judged to be normal That means, is characterized in that comprises a.

[0013]

According to the present invention, the light emitted from the light emitting portion is parallel light, and there is no light divergence. Therefore, regardless of whether the end of the wire to be inspected passes near the light emitting portion or near the light receiving portion, the amount of light blocked by the end of the electric wire is constant. Further, since the light receiving portion is provided with a slit and the irradiation light is received through the slit, the irradiation light is regulated by the slit to a constant amount and a constant range, and the light amount can be accurately detected. .

Further, a signal proportional to the amount of light received by the light receiving portion and a comparison reference value corresponding to the type of wire to be inspected are compared, and when they are in a predetermined matching state, for example, when they match for a certain period of time, Since the peeling of the end of the wire is judged to be normal, it is possible to carry out an inspection with very few erroneous inspections.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 is an illustrative view showing a configuration of a peeling processing inspection device according to an embodiment of the present invention. The inspection apparatus includes an optical inspection unit 10 and a control circuit unit 20 electrically connected to the optical inspection unit 10. The optical inspection unit 10 includes a mounting stay 11
The light emitting device 12 and the light receiving device 13 are attached to the stay 11 so as to face each other with a constant space. The light emitter 12 is composed of a semiconductor laser, and outputs coherent parallel light from its output surface (a surface facing the light receiver 13) 12S toward the light receiver 13.

The light receiving surface 13S of the light receiver 13 has a light emitting surface 12S.
Is opposed to the output surface 12S in parallel, and a slit 14 is formed on the light receiving surface 13S as described later. The end of the electric wire W to be inspected is passed between the light emitter 12 and the light receiver 13 as shown by an arrow A3. At this time, the electric wire W is held by an electric wire clamp (not shown) or the like, and is normally passed between the light emitter 12 and the light receiver 13 at a constant speed.

The light emitter 12 and the light receiver 13 are connected to the control circuit section 20 by connection cables 15 and 16. The control circuit unit 20 has an electric circuit, which will be described later, housed in a case 21. On the front of the case 21, there are various inspection condition setting switches 2 including the power switch 22.
3, a display 24 for voltage, upper limit voltage, lower limit voltage, pass output lamp 25, etc. are provided.

FIG. 2 is a diagram for explaining the shape of the slit 14 provided on the light receiving surface 13S of the light receiver 13 and the operating principle of the light receiver 13. Explaining with reference to FIG. 2, a slit 14 is formed on the light receiving surface 13S of the light receiver 13. In this embodiment, the slit 14 has a width of 1 mm and a length of 10 mm.
The entire surface of the light receiving surface 13S including is irradiated with the laser light from the light emitting portion 12. The end of the electric wire W is moved in the length direction with respect to the slit 14. That is, the electric wire W is passed between the light emitting unit 12 and the light receiving unit 13 so that the shade of the light blocked at the end of the electric wire W moves from one end of the slit 14 toward the other end.

The position of the wire W in the axial direction is defined so that the shade of the exposed core wire C of the end of the wire W intersects the slit 14. The light receiving unit 13 detects a change in the light amount of the laser light obtained through the slit 14 and takes it out as an analog output. Then, the result is used by the control circuit unit 20 to detect the quality of the peeling process.

FIG. 3 is a block diagram showing the electrical construction of the peeling inspection device according to this embodiment. Referring to FIG. 3, the control circuit section 20 includes a CPU 30 as a control center for controlling the entire control circuit. Further, a clock 31 for giving a machine clock as an operation clock to the CPU 30, an EPROM 32 in which an operation program and the like are stored, and reference value data for judging the quality of the peeling process (the core wire diameter for each wire type in a normal case) An EEPROM 33 in which data etc.) is stored is provided and is connected to the CPU 30. Note that the above E
The EPROM 33 may use a backup SRAM.

Further, a display device 35 is connected to the CPU 30 via a display control IC 34. Further, an operation switch 37 is connected via the operation switch control IC 36. The operation switch 37 has
The inspection condition setting switch 23 (see FIG. 2) described above is included, and is used when inputting the wire type to be inspected and the like. The display unit 35 displays the conditions input by the operation switch 37.

Further, a power supply circuit 38 is provided, and the CPU
It is connected to 30. The power supply circuit 30 includes a light emitter 12,
That is, the semiconductor laser 12 is connected, and the laser light is output from the semiconductor laser 12 by the power supplied from the power supply circuit 38. This laser light is received by the light receiver 13. Then, as described above, the light quantity change of the received light is extracted as an analog voltage, converted into a digital signal by the A / D converter 39, and given to the CPU 30.

The CPU 30 compares the digital signal from the A / D converter 39 with the reference value data stored in the EEPROM 33 to determine whether or not the end of the wire has been stripped properly. The result is given to the pass / fail judgment output circuit 40. When the determination result is good, the pass output lamp 25 is turned on. FIG. 4 is a diagram showing a change in the signal level obtained by taking the change in the amount of light detected by the light receiver 13 as a voltage value, and this voltage signal is given to the CPU 30. Then, the CPU 30 determines the quality of the peeling process based on the change in the voltage signal.

FIG. 5 is a flow chart of the process for determining the quality of the peeling process performed by the CPU 30. Next, a description will be given according to the flow of FIG. The peeling inspection of the wire end is performed every time the wire end to be inspected passes between the light emitter 12 and the light receiver 13. The timing and passage time of each wire end passing between the light emitter 12 and the light receiver 13 are substantially constant, and the wire end is passed between the light emitter 12 and the light receiver 13 at intervals of 1 second, for example.

It is preferable that the passage timing signal of the end of the electric wire is given to the control circuit 20, and the CPU 30 determines based on the signal whether or not it is the peeling processing inspection timing of the end of the electric wire. To do. Alternatively, the CPU 30 may independently determine that it is the inspection timing each time a predetermined time has elapsed.

When the CPU 30 determines that it is the inspection timing (step S1), the timer is started and the measurement of the inspection time is started (step S).
2). Next, the amount of light received by the light receiver 13 is converted into an analog voltage, and the detected voltage V _D converted into a digital signal by the A / D converter 39 is read (step S3). Then, the CPU 30 first compares the read detection voltage V _D with the non-interruption voltage V _CC (step S).
4). In this case, in consideration of variations in the detection voltage V _{D and} the like, a predetermined margin α is added, and V _CC −α ≦ V _D ≦
It is determined whether or not V _CC + α.

As a result, if V _CC -α ≤ V _D ≤ V _CC + α, then in step S5, it is determined whether or not the timer has timed out. Immediately after the detection is started, the timer has not timed up, so the processing from step S3 is repeated. The detected voltage V _D during this period is the region 1 in FIG.
As shown in. Next, when the end of the wire to be inspected passes between the light emitter 12 and the light receiver 13, the laser light received by the light receiver 13 is blocked by the core wire at the end of the wire, and the amount of light received by the light receiver 13 decreases. To be done. In this case, in FIG. 2, first, the shadow of the core wire at the end of the electric wire is applied to one end of the slit 14. At this time, the detection voltage V _D becomes that shown in the area 2 in FIG. Then, after that, a state in which the shadow of the core wire at the end of the electric wire blocks the slit 14 continues. At this time, the detection voltage V _D becomes that shown in the region 3 of FIG. Then, the wire end passes between the light emitter 12 and the light receiver 13. C
The PU 30 determines the change in the detected voltage V _D corresponding to the amount of light received by the light receiver 13 during this period as follows.

That is, in step S4, the detection voltage V _D
Is no longer equal to the uninterrupted voltage V _CC (NO in step S4), it is determined whether or not the detection voltage V _D is between the predetermined first reference value V _H and second reference value V _L. (Step S6). These first reference value V _H and second
The reference value V _L is previously stored in the EEPROM 33, and it is read and compared.

If the detected voltage V _D is not between the first reference value V _H and the second reference value V _L in step S6, the processing from step S3 is repeated. When the stripping process of the end of the wire is normally performed, the detection voltage V _D is the first reference value V _H and the second reference with the core wire of the end of the wire blocking the incident light on the slit 14. It is set to be a value between the value _VL . Therefore, if YES is determined in step S6, the count value of the counter C incorporated in the CPU 30 is incremented by 1 (step S7), and it is determined whether or not the count value of the counter C is A. (Step S8).

At first, the count value of the counter C is not A, so the procedure returns to step S3 and the same processing is repeated.
The period in which the core wire at the end of the electric wire blocks the light incident on the slit 14 is a certain time (between the regions 3) as shown in FIG. If the stripping process of the end of the electric wire is normal, the counter C is incremented during the area 3 and set to a predetermined value A. Therefore, whether or not the detection voltage V _D instantaneously becomes a value between the first reference value V _H and the second reference value V _L, and whether the detection voltage V _D lasts for a predetermined time, determines whether the peeling is good or bad. Since it is judged, accurate judgment can be made.

When the counter C counts A in step S8, a normal output is given from the CPU 30 to the pass / fail judgment output circuit 40, and the pass output lamp 25 is turned on (step S9). Then, the counter C is cleared (step S10). On the other hand, before the count value of the counter C reaches A, when it is determined in step S5 that the timer is up, an abnormal output is given to the pass / fail judgment output circuit 40 (step S11). At this time, the pass output lamp 25 is not turned on. Further, at this time, a notification unit may be provided so as to notify that there is a skin peeling defect.

The above processing is performed for each end of the electric wire to be inspected, and the quality of the peeling process is determined for each electric wire. In this embodiment, in step S6, it is determined whether or not the detection voltage V _D is between the first reference value V _H and the second reference value V _L. At this time, since the thickness of the core wire also changes if the type of electric wire changes, the first reference value V _H and the second reference value V _L corresponding to the type of electric wire are stored in the EEPROM 33 in advance.
If the type of wire to be inspected is input by the operation switch 37 before the inspection, the quality of the stripping process of the wire end can be accurately inspected in a short time by the process shown in FIG.

Therefore, there is no need to make fine adjustments according to the core diameter of the electric wire, etc., and it is possible to provide an inspection device that can perform a good peeling inspection of the end of the electric wire regardless of the type of electric wire.

[0034]

According to the present invention, it is possible to provide a peeling processing inspection device capable of accurately performing a peeling processing inspection of an end portion of an electric wire. In particular, it is not necessary to finely adjust the inspection device according to the core diameter of the electric wire, etc., and it is possible to provide an inspection device that can perform a peeling processing inspection even if the type of electric wire changes.

[Brief description of drawings]

FIG. 1 is an illustrative view showing a configuration of a peeling processing inspection device according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a shape of a slit provided on a light receiving surface of a light receiver and an operation principle of the light receiver.

FIG. 3 is a block diagram showing an electrical configuration of a peeling processing inspection device according to this embodiment.

FIG. 4 is a diagram showing a change in signal level extracted as a voltage value based on a change in the amount of light detected by a light receiver.

FIG. 5 is a flowchart of a quality determination process for peeling processing performed by a CPU.

FIG. 6 is an illustrative view showing a state of a peeling process and a terminal crimping process.

FIG. 7 is an illustrative view showing an example in which the peeling process is appropriately performed and an inappropriate example.

FIG. 8 is a diagram for explaining an influence of light divergence when an end of an electric wire passes through a path from a light emitter to a light receiver.

[Explanation of symbols]

 10 Optical inspection unit 12 Light emitter 13 Light receiver 14 Slit 20 Control circuit unit 30 CPU 33 EEPROM

Claims (1)

[Claims] 1. A peeling inspection device for arranging a light emitting part and a light receiving part facing each other at a predetermined interval, irradiating light from the light emitting part toward the light receiving part, and passing the end of an electric wire to be inspected in the optical path. Therefore, a semiconductor laser that emits parallel light or a member equivalent thereto is used for the light emitting unit, and the light receiving unit is configured to receive only light within a predetermined range of the light emitted from the light emitting unit. A slit is provided, and the slit is formed so that its longitudinal direction intersects with the end of the wire to be inspected.The signal output means outputs a signal proportional to the amount of light received by the light receiving part, and the type of wire to be inspected When the storage means in which the comparison reference value is stored in advance, the means for comparing the signal output from the signal output means with the comparison reference value stored in the storage means, and the comparison result of the comparison means are in a predetermined matching state, Stripping the wire end Means for determining the Engineering and normal, stripping inspection apparatus of the wire end portion, which comprises a.