JPH0576563B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of the Invention) The present invention relates to an apparatus for inspecting whether the crimping condition of a crimp terminal crimped to an end portion of an electric wire whose coating has been peeled off to expose the core wire is good or bad.

(Description of prior art) When crimping a terminal to the end of a covered wire, the covering of the end of the covered wire is cut to a certain length, the coating is peeled off by a certain length, and a terminal of a certain shape and size is attached to the end of the wire. Crimp. FIG. 1A shows a perspective view of the terminal crimping part of the electric wire W with the terminal T crimped thereon, and FIG. 1B shows a front view thereof. In terminal crimping, as shown in Figure 1A and B, cover gripping part T _a
securely grips the sheathing part W _a of the electric wire W over the entire circumference and leaving only a certain length from the sheathed end, and the core wire gripping part T _b securely grips the core wire part W _b of the electric wire W over the entire circumference. It is necessary to grasp it and crimp it. However, the covering gripping part T _a is the core wire part.
W _b may be grabbed (so-called "hanging defect"), or the core wire gripping portion T _b may be grasping the covering portion W _a (so-called "resin biting defect"). Figure 2 A, B
3A and 3B respectively show a perspective view and a front view of the terminal crimping part in the case of "hanging failure".
A perspective view and a front view of the terminal crimping part in the case of "poor resin binding" are shown, respectively. Judging the quality of terminal crimping by visual inspection is cumbersome and inaccurate, and as terminal crimping equipment becomes more automated, it requires a lot of manpower to keep up with the speed. is being automated.

For example, there is a conventional inspection device that directly measures the length of the sheathing portion W _a that is left ungrasped by the sheath gripping portion T _a from the end of the wire to which the terminal has been crimped.
In the case of such an optical inspection apparatus, the above-mentioned measurement is performed by projecting light onto the surface to be inspected of the electric wire terminal and receiving the reflected light with a television camera, line sensor, or the like. Covering part W _a that is left ungrasped
Because it directly measured the length, color identification was required, and even the slightest change in the position or posture of the wire being inspected caused large fluctuations in the amount of reflected light, making reliable inspection impossible. In addition, it requires a condensing lens, making the configuration complicated and expensive. There was also the problem that the color extraction of the terminal, core wire, and wire sheathing became subtle due to intermediate colors, making it complicated to set a reference level for determining the quality of terminal crimping in application software.

(Objective of the Invention) The present invention solves the problems of the prior art as described above, and provides an optical crimp terminal crimp state inspection device that can perform accurate inspection with a simple configuration. The purpose is

(Structure of the Invention) A terminal to which the present invention is applied has a covering gripping part and a core gripping part, and an intermediate window part is provided between them. This terminal is crimped onto the wire end such that the covering gripping portion and the core wire gripping portion respectively grip the covering portion and the core wire portion of the wire end whose covering has been peeled off to expose the core wire.

According to this invention, the crimping condition inspection device includes an imaging means for capturing a side silhouette image of the intermediate window of the crimp terminal and providing binary image data of the side silhouette; A plurality of test points are set in a vertical and horizontal grid pattern within the normal range that should exist and located outside the core line.
By determining whether the binary image data of each point to be inspected in the side silhouette image is "1" or "0", a right-angled equivalent portion is determined to represent the tip of the covering part at a position within the normal range. The structure includes a determining means for determining whether or not the crimping is present, and determining that the crimping is good if the crimping is present, and determining that the crimping is poor if the crimping is not present.

(Description of Embodiment) FIG. 4 is an explanatory diagram schematically showing an embodiment of the crimp terminal crimp state inspection device according to the present invention. This inspection device captures a side silhouette image of the intermediate window (the part circled by the dotted line in Figures 1 to 3B) formed between the covering gripping part T _a and the core wire gripping part T _b of the terminal T. a television camera 1 as an imaging means for the purpose of the camera, a light source 2 for irradiating the intermediate window with illumination light, and a diffusion surface 3 for diffusing the illumination light from the light source 2 to provide an imaging background of uniform brightness. It is equipped with These television camera 1, light source 2, and diffusion surface 3 are arranged, for example, on both sides of a transfer route for crimped terminals T in an automatic terminal crimping device.
They are placed facing each other on both ends.

5A to 5C show typical side silhouette images of the intermediate window portion of the crimped terminal T taken by the television camera 1. FIG. 5A is a side silhouette image of the intermediate window in FIG. 1B (in case of good crimping), and FIG. 5B is a side silhouette image of the intermediate window in FIG. 2B (in case of poor hanging); Further, FIG. 5C is a side silhouette image of the intermediate window portion of FIG. 3B (in the case of poor resin filling).

As is clear from FIGS. 5A to 5C, in the case of good crimping (FIG. 5A), the covering _portion W a of the electric wire W
A right-angled portion representing the tip of the right-angled portion appears as a silhouette within the intermediate window, but in other cases, this right-angled portion does not exist. In the case of a typical "hanging failure" (FIG. 5B), there is no silhouette corresponding to the covering section W _a within the intermediate window section.
In addition, in the case of typical “poor resin bite” (No. 5C
In the figure), the silhouette of the covering part W _a draws a gentle curve within the intermediate window part. In this invention, the quality of the crimp state of the terminal T is determined by determining whether or not the portion corresponding to the right angle appears as a silhouette within the intermediate window portion.

The determination method will be described below. The solid line in FIG. 6 shows the contour line near the middle window of the terminal T imaged by the television camera 1, and the dotted line inside the middle window is a virtual line showing the general position of the core line. A total of 18 lattice points formed by the lattice 4 (consisting of vertical lattices a to f and horizontal lattices p to r) on this virtual line are inspection points in the captured silhouette image (dot positions in the image). It shows. By examining the image data of these inspection points, it can be determined whether or not a right-angled portion representing the tip of the covering portion W _a exists within the intermediate window portion, as described below. In addition, this point to be inspected is within the normal range where the tip of the sheathing part W _a where the terminal T is well crimped should be, and the inspection target (wire and terminal) is
It is determined appropriately depending on the shape and dimensions of the

FIG. 7 is a schematic block diagram showing an example of an image processing device (determination means) for determining the quality of terminal crimping by examining image data of a point to be inspected. This image processing device receives image data from a television camera 1 (Fig. 4), performs binarization processing on it, and converts it into 2
a binarization circuit 5 for converting into value image data;
An image memory 6 for reading and fixing this binary image data, a CPU 7 for reading the binary image data fixed in the image memory 6 and performing predetermined image processing (described later), and a processing program. The image memory 6, CPU 7, ROM 8, and control means 9 are interconnected by a system bus 10. There is.

The binarization circuit 5 compares the brightness value of each dot of the image data provided from the television camera 1 (FIG. 4) with a predetermined threshold value, and when the threshold value is exceeded, the value is set to "1", If it does not exceed the value, convert it to “0”2
Value conversion processing is performed for each dot. In this way, it is possible to obtain binary image data in which relatively bright background portions are represented by "1" and relatively dark silhouette portions are represented by "0".

FIG. 8 is a flowchart schematically showing the operation of the image processing apparatus. The operation of the image processing apparatus shown in FIG. 7 will be described below with reference to FIG. First, in step S1, image data binarized by the binarization circuit 5 is loaded into the image memory 6. This image data is taken in at the timing when the crimped terminal T comes to the imaging position of the television camera 1. For example, in the case where the terminal T does not stand still in the middle of a terminal crimping processing line (for example, in an automatic terminal punching machine), a photo sensor or the like detects that the terminal T has come to the imaging position, and the control means 9 controls the light source. A still silhouette image of the terminal T may be captured by emitting a strobe light. For example, in the case where the terminal T temporarily stops at every appropriate processing pitch in the middle of the processing line (for example, in a system wire processor), the image capturing position is set as the stationary position, and the stationary silhouette is controlled by the control means 9. Images may also be imported.

Subsequently, in step S2, the CPU 7 reads this image data from the image memory 6 in response to the notification of completion of the capture from the control means 9. Then in step S3
According to the program in the ROM 8, the CPU 7 identifies the data content of each grid point.

As can be easily understood by referring to FIGS. 5A to 5C, the identification result corresponds to one of the following three cases. Note that a white circle on each grid point in FIGS. 5A to 5C indicates that the image data at that dot position is "1" representing a background part, and a black circle indicates that the image data at that dot position is "0" representing a silhouette part. ”.

Case 1 (in the case of hanging, FIG. 5B): All 1 (image data of all grid points are "1").

Case 2 (If the crimping is good, Fig. 5A) ...Case 1 does not apply, and each vertical grid a~
f is all "0" (the image data of the grid points on the vertical grid are all "0") or all "1" (the image data of the grid points on the vertical grid are all "1").

In FIG. 5A, the vertical grids a to d are all "0", and the vertical grids e and f are all "1".

Case 3 (in case of resin bite failure, Fig. 5C) ... Neither case 1 or 2 applies.

That is, the vertical grids b, c, d in FIG. 5C
There is a vertical grid having both "1" grid points and "0" grid points, as shown in FIG.

Returning to FIG. 8, in step S4, it is determined whether or not the above case 1 applies. If it is determined that this is the case, a "hanging failure" has occurred, and the process proceeds from step S4 to step S6, where the CPU 7 issues a command to the control means 9 to indicate a "crimping failure." If not, processing continues in steps
Proceed from step S4 to step S5.

In step S5, it is determined whether or not the above case 2 applies. If it is determined that this does not apply, "poor resin bite" has occurred, and the process proceeds from step S5 to step S6 above.
The CPU 7 issues a command to the control means 9 indicating "defective crimping". If it is determined that the above case 2 applies, the process proceeds from step S5 to step S7.
The CPU 7 instructs the control means 9 to indicate "good crimping".

The control means 9 performs predetermined control based on the given command. For example, when receiving a "defective crimping" command, the series of terminal crimping processes may be stopped and the operator may remove the defective products, or the defective products may be automatically selected.

Note that as the imaging means, it is also possible to use suitable means other than a television camera, such as a CCD.

(Effects of the Invention) As described above, according to the present invention, a side silhouette image of the intermediate window of a crimp terminal is analyzed using binary image data at a plurality of inspection points set in a vertical and horizontal grid pattern, and Since the quality of terminal crimping is determined by determining whether or not there is a right-angled portion representing the tip of the covering part within the normal range within the intermediate window, color identification is not necessary. Even though it is an optical type, it has a simple configuration and can perform inspections with high accuracy.

[Brief explanation of the drawing]

FIGS. 1 to 3 are diagrams showing various states of terminal crimping, FIG. 4 is a schematic explanatory diagram showing an embodiment of the present invention, and FIGS. 5A to C are diagrams showing silhouette images of the intermediate window. FIG. 6 is a diagram showing the outline of the intermediate window, FIG. 7 is a schematic block diagram of the image processing circuit, and FIG. 8 is a flowchart showing the operation of the image processing circuit. 1... Television camera, 5... Binarization circuit, 6...
...Image memory, 7...CPU.

Claims (1)

[Scope of Claims] 1. An intermediate window is provided between the covering gripping part and the core wire gripping part, and the covering part and the core wire part of the wire terminal, which has been peeled off and the core wire is exposed, are held between the covering gripping part and the core wire gripping part. In an apparatus for inspecting the crimped state of a crimp terminal crimped to the wire end so as to be gripped at each end, the crimp terminal is configured to image a side silhouette image of an intermediate window portion of the crimp terminal and provide binary image data of the side silhouette. a plurality of inspection points are set in a vertical and horizontal grid pattern within a normal range in which the tip of the covering portion in the intermediate window should exist and outside the core line portion, and each of the points in the side silhouette image is By determining whether the binary image data of the inspection point is "1" or "0", it is determined whether a right-angled portion representing the tip of the covering part exists at a position within the normal range. 1. A crimp terminal crimping state inspection device, comprising: determining means for determining that crimping is good when present, and determining that crimping is poor when absent.