JPH02183917A - Method for measuring flat cable conductor position - Google Patents

Abstract

PURPOSE:To allow conductor pitch to be determined by measuring the position of a conductor within a flat cable by the distribution of light that passes through the flat cable and is received for measurement and by the distribution of light that is reflected by the flat cable. CONSTITUTION:Light L sent out from a light source 11 passes through a half mirror 12 and a strikes a covering layer 2 of a flat cable 1 that moves in an 'A' direction indicated by an arrow. The light L striking a portion of the covering layer 2 where there is no conductor 3 passes through it and enters a light receiving element 13. The light L, on the other hand, is cut off when it hits a portion where there is a conductor 3. Thus, an output signal Ea from the light receiving element 13 goes to either 'H' or 'L' depending on the presence or absence of a conductor 3. The light L which has been reflected by a conductor 3 in the cable 1 is again reflected by the half mirror 12 and enters a light receiving element 14 as reflected light L', causing output of a signal Eb. Each conductor 3 is recognized by detecting the peak value of the output signal Eb. A signal processing circuit 16 measures the width T of the incoming signal Ea at its 'L' level to determine the conductor pitch when T is equal to the diameter of the conductor 3.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for measuring the position of a conductor in a flat cable.

(Prior art) With the spread of electronic equipment, flat cables, i.e. metal wires (
A large number of conductors (hereinafter referred to as conductors) are arranged in parallel at small intervals,
Demand for cables that are integrally insulated by insulating materials and formed into a band shape is increasing, and in response to this, there is a strong demand for automating the process of connecting each terminal of a large number of parallel conductors of the flat cable to a connector. has been done. In order to automate the connection of such a large number of parallel conductors and connectors, the total width of the flat cable, the margin (distance from the edge of the flat cable to the center of the outermost conductor), and the center distance of each parallel conductor are required. It is necessary that the dimensions of each part, such as (pitch) and the distance between the centers of the conductors on both sides (total pitch), are accurately set to specified values. Therefore, it is necessary to measure the dimensions of each of these parts with high precision, and this is usually done visually.

(Problem to be solved by the invention) However, it is extremely difficult to accurately measure each dimension such as the center distance (hereinafter referred to as pitch) and the margin between a large number of conductors arranged at small intervals by visual inspection. It is a lot of work, and the work efficiency is also poor.

When measuring the conductor position, that is, the pitch, of a flat cable as shown in Figure 5 (c), if the coating layer 2 of the flat cable l is transparent or semi-transparent, the flat cable 1 should be illuminated with light. When irradiated, the transmitted light amount distribution becomes a dark part in a certain part of the conductor 3 as shown in FIG. The method of measuring the transmitted light amount distribution is to place a TV camera etc. on the opposite side of the light source,
This is done by performing image processing.

However, if the adjacent conductors 3.3 are in close contact with each other as shown in the figure, or if the gap is at an extreme value, the transmitted light distribution will be
The dark portion becomes one, and the two adjacent conductors 3.3 cannot be recognized separately, and are recognized as one thick conductor. As a result, this causes a serious error in pitch measurement.

The present invention has been made in view of the above-mentioned points, and is a flat cable conductor position measurement system that is capable of recognizing the center of each conductor and measuring the pitch even when adjacent conductors in the flat cable are in close contact with each other. The purpose is to provide a method.

(Means for Solving the Problems) In order to achieve the above object, according to the present invention, light is emitted from one side of a flat cable, light is received on the other side of the flat cable, and light is transmitted through the flat cable. measuring the distribution of light reflected by the flat cable on the one side of the flat cable,
The position of the conductor within the flat cable is measured based on the distribution of transmitted light and the distribution of reflected light.

(Function) The bright part of the transmitted light of the flat cable is the part without conductor,
The dark area represents a certain part of each conductor, and each peak value of reflected light represents the apex of each conductor in the flat cable.Therefore, if there is no possibility that the conductors in the flat cable are in close contact, the transmitted light The pinch between each conductor is measured, and if there is a possibility that adjacent conductors are in close contact, the pitch between each conductor is measured based on the reflected light distribution. This makes it possible to accurately measure the position of the conductor within the flat cable.

(Example) An embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 shows a measuring device for carrying out the method of the invention,
The measuring device 10 includes a light source 11, a half mirror 12, and 2
The light receiving elements 13 and 14 are provided. The light source 11, the half mirror 12, and the light receiving element 13 are arranged on the optical axis 15, and a flat cable 1 is movable in the width direction between the half mirror 12 and one of the light receiving elements 13. The other light receiving element 14 is arranged on the side of the half mirror 12 at right angles to the optical axis 15.

For example, the light source 11 emits beam-shaped light, and the optical axis 15
The light receiving element 13 arranged above receives and detects the beam-shaped transmitted light that is irradiated from the light source 11 and transmitted through the coating layer 2 of the flat cable 1, and generates an electric signal Ea according to the amount of received light.
Output. The light receiving element 14 receives and detects the reflected light L' that is emitted from the light source 11, is reflected by the conductor 3 of the flat cable l, and reaches the half mirror 12, and is further reflected by the half mirror 12, and generates electricity according to the amount of light received. A signal Eb is output. The output signals Ea and Eb of each of these light receiving elements 13 and 14 are input to the signal processing circuit 16. The signal processing circuit 16 measures the pitch of each conductor 3 of the flat cable 1 based on the input signals Ea and Eb.

A method of measuring the pitch of each conductor 3 of the flat cable 1 will be described below.

Light is irradiated from a light source 11, and a flat cable 1 is placed between a half mirror 12 and a light receiving element 13, and is moved in parallel in the direction shown by arrow A. The light irradiated from the light source 11 is directed to the half mirror 12 and is irradiated to the coating N2 of the flat cable 1.

This light passes through the portions of the covering layer 2 where there is no conductor 3 and reaches the light receiving element 13 . Further, in the portion of the coating layer 2 where the conductor 3 is present (see FIG. 2(a)), its transmission is blocked and the light receiving element 13 does not output a signal. Therefore, the output signal Ea of the light receiving element 13 is It changes in a pulsed manner as shown in b). That is, the output signal Ea of the light receiving element 13 is at a high level in a portion where the conductor 3 is not present, and is at a low level in a portion where the conductor 3 is present.

Furthermore, the light irradiated onto the conductor 3 of the flat cable 1 is reflected by the conductor 3 and reaches the half mirror 12, and is further reflected by the half mirror 12, resulting in reflected light L.
The light is irradiated onto the light receiving element 14 as .degree. The light receiving element 14 receives this reflected light L' and outputs a trigger-like signal Eb as shown in FIG. 2(C). The apex of each waveform of this signal Eb coincides with the apex 3a of each conductor 3 (FIG. 2(a)) when the optical axis of the irradiated light and the optical axis of the reflected light L° are coincident. , indicates the center position of each conductor 3, therefore, the light receiving element 1
By detecting each peak value of the output signal Eb of 4,
Even if adjacent conductors 3 are in close contact with each other, it is possible to separate and recognize each conductor.

For example, the signal processing circuit 16 processes the low-level amplitude (hereinafter referred to as pulse width) of the signal Ea input from the light receiving element 13.
T is measured, and the pulse width T is equivalent to the diameter φ of the conductor 3 (
When T=φ), it is determined that adjacent conductors are separated from each other, and the center distance between each conductor 3, that is, the pitch is measured using the signal Ea. That is, in this case, the signal Ea
The pitch is determined by measuring the distance between the centers of each low level part of the pitch. Note that the diameter φ of the conductor 3 is known.

Further, the pulse width T is larger than the diameter φ of the conductor 3 (T>
When φ), it is determined that the adjacent conductors 3 are in close contact with each other, and the center distance between each conductor 3 is measured based on the signal Eb inputted from the light receiving element 14. That is, in this case, the distance between each vertex of the signal Eb is measured and used as the pitch.

As a method of detecting the center of the conductor 3 from the reflected light L°, for example, an appropriate threshold value is set, a pulse signal is formed by the signal exceeding the threshold value, and the center of the pulse signal is set as the center of the conductor 3. Alternatively, the pitch between each conductor may be measured.

By the way, since the reflected light L° at -a is weak, if the conductor 3 is not in close contact, it is more stable to measure by determining the center of the dark part of the transmitted light as the center of the conductor 3. . Therefore, when there is no possibility that adjacent conductors are in close contact with each other, the pitch is measured using transmitted light, and only when there is a possibility that they are in close contact, the pitch between the conductors 3 is measured from the reflected light L°. It is preferable to do so.

In addition, the transparency of the coating layer 2 of the flat cable l is low,
When detecting the position of the conductor 3 in the flat cable 1 when sufficient light does not pass therethrough, a method of receiving reflected light from the conductor 3 is effective.

For example, when the light transmittance of the coating layer 2 shown in FIG. 3(a) is not so bad, the transmitted light distribution changes as shown in FIG. distance from the edge) can be measured.

However, when the light transmittance is poor, the transmitted light distribution becomes as shown in Figure 3 (C), and the clear position of the conductor 3 cannot be found. Therefore, in this case, the reflected light from the conductor 3 When the light is received, the reflected light distribution becomes as shown in FIG. 4(d), and a signal Eb may be obtained. This is the fourth
As shown in the figure, the amount of attenuation of the transmitted light is determined by the thickness D of the coating layer 2, whereas the amount of attenuation of the reflected light L° is determined by the distance from the top surface 2b of the coating layer 2 to the vertex 3a of the conductor 3. 2
This is because the latter distance is shorter due to the structure of the flat cable l, and the amount of light attenuation is smaller. In this case, the width of the coating J12 of the flat cable l is measured based on the waveform of the transmitted light, and the position of the conductor 3 is measured based on the waveform of the reflected light L°.
It becomes possible to detect the position of each conductor 3 inside.

Further, the light receiving element 13 is connected to the coating layer 2 of the flat cable 1.
When the edge 2a (Fig. 3(a)) crosses the irradiation light,
Transmitted light is received, and as a result, the amount of received light decreases, and the output signal Ea of the light receiving element 13 decreases. The signal Ea at this time changes substantially in the same manner as the transmitted light distribution shown in FIG. 3(a). The signal processing circuit 16 detects the edge 2a of the coating layer 2 of the flat cable l based on the decrease in the signal Ea inputted from the light receiving element 13. Then, by the edge signal representing this edge and the output signal Eb from the light receiving element 14 by the first conductor 3 after the detection of the edge signal, the center of the conductor 3 which is also outside by the corresponding amount from the edge 2a of the coating layer 2. Measure the distance, ie, the margin. At this time, the output signal Eb of the light receiving element 14 changes approximately in the same manner as the reflected light distribution shown in FIG. 3(d).

In the above embodiment, a case has been described in which the conductor position of the flat cable 1 is measured by moving the flat cable l and fixing the measuring device 10. However, it is possible to move the measuring device 10 without moving the flat cable l. Alternatively, instead of the light source 11, a small spot light may be scanned in parallel and at a constant speed, and the pitch between each conductor 3 may be measured from the time interval of the obtained light distribution.

In addition, as a method of using a television camera, by illuminating the entire flat cable 1 and obtaining a transmitted image and a reflected image in the same manner as described above, each signal due to transmitted light and reflected light is Figure 2 (b) and (C)
It becomes possible to measure the pitch between conductors.

The margin and each pitch are measured, for example, by counting the number of clock pulses between the edge signal, the first conductor detection signal, and each conductor detection signal. in this case,
As a clock pulse signal, the movement of the light source or the object to be measured (
For example, pulses synchronized with scanning) are applied every 1 μm of the moving path
By using the pulse signal that is output as a pulse, the margin and each pitch can be accurately measured even when the light source or the object to be measured moves at an inconstant speed.

(Effects of the Invention) As explained above, according to the present invention, light is irradiated from one side of a flat cable, the light is received on the other side of the flat cable, and the distribution of light transmitted through the flat cable is measured. Measure the distribution of light reflected by the flat cable on the one side of the flat cable, and determine the position of the conductor in the flat 4° cable based on the distribution of transmitted light and the distribution of reflected light. By measuring, even when adjacent conductors in a flat cable are in close contact with each other, it is possible to accurately measure the pitch between the centers of each of these conductors. Furthermore, the method has excellent effects such as a simple measurement method.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of the flat cable conductor position measuring method according to the present invention, FIG. 2 is a signal waveform diagram detected by a measuring device for carrying out the measuring method of FIG. 1, and FIG. 4 is a signal waveform diagram showing another embodiment of the measuring method of the present invention, FIG. 4 is a diagram showing the relationship between transmitted light and reflected light of a flat cable, and FIG. 5 is a conventional method for measuring the conductor position of a flat cable. and a signal waveform diagram obtained by the method. 1... Flat cable, 2... Covering layer, 3...
Conductor, 10... Conductor position measuring device, 11... Light source,
12... Half mirror 113, 14... Light receiving element,
16...Signal processing circuit. Figure 1E. Figure 2

Claims (1)

[Claims] Light is irradiated from one side of the flat cable, the light is received on the other side of the flat cable, and the distribution of light transmitted through the flat cable is measured, and the light reflected by the flat cable on the one side of the flat cable. A method for measuring the position of a conductor in a flat cable, characterized in that the position of the conductor in the flat cable is measured based on the distribution of transmitted light and the distribution of reflected light.