JPH0563742B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for inspecting a terminal crimped portion of a terminal crimped electric wire in which a terminal is crimped to an end portion from which a coating has been peeled off.

(Description of Prior Art) When crimping a terminal to the end of a covered electric wire, the covering of the end of the covered wire is cut to a certain length and the coating is peeled off by a certain length, and a terminal of a certain shape and size is crimped to the end of the wire. do. FIG. 1A shows a perspective view of the terminal crimping portion of the electric wire W with the terminal T crimped thereon, and FIG. 1B shows a plan view thereof. In terminal crimping, the first gripping portion Ta is attached to the wire W as shown in Figure 1.
The second grip part Tb securely grips the sheathing part Wa of the electric wire W over its entire circumference, leaving only a certain length L from the sheathing end, and the second gripping part Tb securely grips the conductor (core wire) part Wb of the electric wire W over its entire circumference. It is necessary to grasp it and crimp it. However, if the first grip part Ta grips the conductor (core wire) part Wb (so-called "hanging")
(defect), the second grip part Tb grips the covering part Wa (so-called "resin grip" defect), or the first grip part
Ta may be crimped without firmly grasping the covering portion Wa (so-called "misalignment"). Judging the quality of terminal crimping by visual inspection is cumbersome and inaccurate, and with the automation of terminal punching machines, it requires a lot of manpower to keep up with the speed. is being automated. Also, from the pending applications of the same applicant as this invention, Japanese Patent Application Laid-Open No. 57-60249 and Japanese Patent Application Laid-Open No. 57-61903
No., JP-A-57-144474, JP-A-57-175942,
JP-A-58-95911 and JP-A-58-135440 have been published. However, with these devices, the terminal is directly connected to the first grip part Ta from the wire end where the terminal is crimped.
This is to measure the length L of the covering part that is left ungrasped. In the optical type, the above measurement is performed by projecting light onto the surface to be inspected of the wire terminal and receiving the reflected light with a television camera or line sensor. Since it directly measured L, color identification was required, and the amount of reflected light fluctuated greatly even with slight changes in the position or posture of the wire being inspected, making reliable inspection impossible. , the configuration was complicated and expensive, as it required a condensing lens. In addition, when performing an inspection, it is necessary for the wire end to be stationary, so it is not possible to inspect the wire end in a device such as an automatic terminal puncher where the wire end does not stand still on the path where it is supplied or sent out to the terminal crimping section. I couldn't do it.

(Object of the Invention) This invention was made in view of the problems of the prior art as described above, and provides a terminal crimping method for terminal crimping electric wires that is an optical method but has a simple structure and can be inspected with high precision. The purpose of this study is to provide a method for inspecting parts of the body.

(Structure of the Invention) According to the present invention, at least one light source and at least one imaging means are disposed facing each other across the transfer route of the terminal crimped electric wire, and include before and after terminal crimping. A silhouette image of the terminal crimping portion is captured in at least one state. Predetermined dimensions are measured based on image data obtained by imaging, and the condition of the terminal crimping portion is inspected.

The predetermined dimension is the length l ₁ between the gripping position of the terminal-crimped electric wire with the sheath removed by the wire support device and the sheathing peeling position of the terminal-crimped electric wire with the sheath peeled off in the state before terminal crimping, and the above-mentioned coating. At least one of the length l ₂ between the peeling position and the core wire tip position, and the length l ₃ between the gripping position and both end positions of the crimp terminal in the state after the terminal is crimped. The length is at least one of l ₄ .
Then, before the terminal crimping, the measured l ₁ ,
Find l ₁ based on at least one of l ₂ ,
The terminal crimping condition is determined to be good or bad depending on whether or not this is within a predetermined range. After the terminal crimping, at least one of the measured l ₁ and l ₂ and l ₃ and l ₄
Based on at least one of the above, the length of the covering portion of the terminal crimped electric wire that is not gripped by the gripping portion of the terminal is determined, and whether the length is within a predetermined range or not is used to determine whether the terminal crimped state is good or bad.

(Description of Embodiments) As a preferred embodiment, a terminal crimping electric wire supplied to a wire cutter and a wire stripper is provided with a support device by rotating an arm at its tip.
DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a terminal crimping device in which a wire end (terminal crimping portion) from which the coating has been peeled is supplied to a terminal punching machine will be described with reference to the drawings.

As shown in FIG. 2, the electric wire W supplied from a known electric wire supply device (not shown) is connected to a known electric wire support device 1.
The terminal is fed to a known wire stripper 2. The wire support device 1 includes an arm 3
is installed at the tip of the The arm 3 rotates around a rotation shaft 4 connected to a power device (not shown), and returns the wire support device 1 to the wire stripper position and the terminal punch position. The terminal punching machine 5 is a known one that sequentially crimp the continuous crimp terminals T wound on a reel one by one. A known wire cutter 6 is attached to the tip of the wire stripper 2. Then, the wire is supplied, the coating is removed by the wire stripper 2,
Rotation of arm 3, terminal punching operation, wire cutter 6
The operations are performed in sequence under the control of a known control device (not shown).

On the transfer path 7 where the electric wire W is transferred from the wire stripper 2 to the terminal punching machine 5 and vice versa, electric power is supplied from a power source (not shown) facing the electric wire W passing therebetween. A strobe light source 8a and a monochrome television camera 8b are provided, and the terminal of the electric wire W (terminal crimping part)
A photo sensor 8c detects that the has come to this position.
is provided. The light source 8a, the television camera 8b, the photosensor 8c, and a known image processing device (FIG. 6) form a measuring means for measuring a predetermined dimension of the terminal crimped portion of the electric wire W.

In response to the detection output of the photosensor 8c that detects the arrival of the terminal crimped portion of the electric wire W, a strobe light emission command is input to the light source 8a, and image data is captured from the television camera 8b to the image processing device. .

Next, its effect will be explained. An electric wire W supplied from an electric wire supply device (not shown) passes through the electric wire support device 1 and is pushed out by a length that allows for an appropriate length L of the sheathed portion left ungrasped when the terminal is crimped (see Figure 1). . In this state, the wire support device 1 grips the wire W, and the wire end is supplied to the wire stripper 2. Here, wire stripper 2
The blades 2a sandwich the wire W and keep it cut into the covering portion. Next, as the arm 3 rotates due to rotation of the rotation shaft 4 by power (not shown), the electric wire W is pulled out from the cut coating, the coating is peeled off at the terminal crimping part, and the core wire is lengthened to a predetermined length. It is stripped bare and transported along the forward path of the transport path 7 in the direction of the terminal punching machine 5. At this point, the blade 2a of the wire stripper 2 is opened. During the transfer, when the terminal crimping portion of the electric wire W approaches a position facing the light source 8a and the television camera 8b, the photosensor 8c detects the arrival of the electric wire W and outputs a detection signal. In response to the detection signal, the light source 8a emits strobe light, and the silhouette image data of the terminal crimped portion of the terminal of the electric wire W, which is imaged by the television camera 8b, is taken into the image processing device (FIG. 6). The terminal crimping portion at the end of the electric wire W at this time is as shown in FIG. 3A, and image data as shown in FIG. 3B is captured as a silhouette image thereof. Then, using known image recognition technology, the length l ₁ from the reference position R of the electric wire W (in this case, the gripping position of the wire support device 1) to the sheathing peeling position and the tip position of the exposed core wire from the sheathing peeling position are determined. At least one of the lengths l ₂ is determined.

Next, the terminal crimping part of the terminal of the electric wire W is pressed with the terminal punching machine 5.
When the arm 3 reaches the terminal punching position, the rotation of the arm 3 is stopped and the terminal punching operation is performed. When the terminal T is crimped to the terminal crimping portion of the electric wire W, the arm 3 begins to rotate in the opposite direction again, and the terminal crimped electric wire W returns to its original position on the return path of the transfer path 7. On the way, when the terminal crimping part of the electric wire W approaches the position where the light source 8a and the television camera 8b face each other, the photosensor 8c detects the arrival of the electric wire W and outputs a detection signal, and the light source 8a emits strobe light. The television camera 8b captures a silhouette image of the terminal crimped portion of the terminal of the electric wire W, and the image data is taken into the image processing device (FIG. 6) by the detection output of the photosensor 8c. The terminal crimping portion of the electric wire W terminal at this time is as shown in FIG. 1, and image data as shown in FIG. 4 is captured as a silhouette image thereof. Then, using known image recognition technology, the length from the reference position R of the electric wire W (the gripping position of the electric wire support device 1 as in the above case) to one end and the other end of the terminal (the end and the tip of the wire gripping part) is determined. The length of at least one of l ₃ and l ₄ is determined. In the case of small terminals, it may be difficult to distinguish between the gripping portion Ta and the covering portion Wa on the outline image, and in such cases it is particularly effective to determine _l4 .

Subsequently, the arm 3 rotates back to its original position, the wire support device 1 loosens its grip, and the wire W with the terminal crimped is moved forward by a predetermined length, and the blade of the wire cutter 6 closes to cut it. . After cutting, the blade of the wire cutter 7 opens and the terminal crimping device shown in FIG. 2 returns to its initial state.

Next, with reference to FIG. 5, an example of a method for inspecting the condition of the terminal crimped portion of the electric wire W using the lengths l ₁ to _{l 4} determined as described above will be described. first,
We will explain the use of l ₁ and l ₂ . When examining the terminal crimping condition, we found that the length from the wire reference position (gripping position of wire support device 1) to the coating peeling position
Although l ₁ is appropriate, there are almost no cases where the grip position during crimping is incorrect (poor hanging, resin gripping). That is, it is no exaggeration to say that the failure of terminal crimping is due to the failure of the length l ₁ from the reference position of the electric wire to the position where the coating is peeled off. Then, the length of this electric wire from the reference position to the coating peeling position is l ₁
The defect is caused by the fact that the sheathing remaining on the wire expands and contracts randomly when the wire is pulled out from the sheath, even though the position where the wire stripper blade 2a enters is constant. Therefore, by measuring the above l ₁ just before crimping the terminal (at the time when the expansion and contraction of the above-mentioned coating is almost completed),
Hanging defects and resin chewing defects can be fully predicted.
That is, when l ₁ is smaller than a predetermined value, a hanging defect can be predicted, and when l ₁ is larger than a predetermined value, a resin bite defect can be predicted. Also, since the core wire does not expand or contract, the length l from the reference position to the core wire tip position is always constant, and l = l ₁ + l ₂ , so
By measuring l ₂ , the same effect as indirectly measuring l ₁ can be obtained. Furthermore, by measuring both l ₁ and l ₂ , it is possible to detect not only hanging defects and resin bite defects, but also defects in which the exposed core wire is cut (in this case, l ₂ = 0). It becomes possible to do so.

Next, the use of l ₃ and l ₄ will be explained. l ₃ and l ₄ are used in combination with the above l ₁ and l ₂ , and by calculating indirectly the length L of the covering part Wa that is not gripped by the grip part Ta, it is possible to prevent hanging problems, Detects resin bite defects. The basic formula for the calculation is as follows, assuming that the length of the gripping portion Ta of the terminal T is D.

L=l ₁ −l ₃ −D Here, since l ₁ =l−l ₂ and l ₃ =l ₄ −l _T , the above equation can be transformed into the following three equations. However, l _T is the length of terminal T.

L=l−l ₂ −l ₃ −D L= _{l 1} −l ₄ +l _T −D L=l−l ₂ −l ₄ +l _T −D Now l, l _T , and D are set in advance depending on the type of terminal. Since this is known, L can be calculated indirectly by measuring at least one of l ₁ and l ₂ and one of l ₃ and l ₄ , and the hanging injury (L is L is smaller than a predetermined value) and resin grip failure (L is larger than a predetermined value) can be detected.

FIG. 6 is a schematic block diagram showing an example of an image processing device. In the figure, the television camera 8b
The output of (FIG. 2) is connected to the binarization circuit 9. The output of this binarization circuit 9 is connected to RAM10. The CPU 11 reads image data from the RAM 10 and together with the RAM 10 constitutes a known image recognition means for determining predetermined dimensions (l ₁ to _{l 4} described above). Further, the CPU 11 also constitutes a comparing means for comparing the size data obtained by the image recognition means with the data of the permissible range read from the ROM 12. The ROM 12 stores programs for recognizing and comparing these images, and also stores data on the permissible range of the dimensions. RAM
10, CPU 11, ROM 12 and control means C
are connected by a system bus 13. In response to the detection output of the photosensor 8C (FIG. 2), the control means C causes the light source 8a to flash when the terminal crimped portion of the electric wire W comes to the inspection (imaging) position, that is, the position where the light source 8a and the television camera 8b face each other. At the same time as emitting light, still image data is loaded into the RAM 10, and a loading completion notification signal is given to the CPU 11.
Depending on the selection in the control means C, a program corresponding to the type and size of the terminal and the type and size of the electric wire to be used may be made executable.
The CPU 11 provides the control means C with a signal indicating whether the measurement result of the required dimensions of the terminal crimping portion of the electric wire W is good or bad.

FIG. 7 shows a flowchart for the above l ₁ and l ₂ measurements. In the following description, of the reciprocating electric wire W transfer path 7 (see FIG. 2), the terminal crimping portion imaging position on the outward path is shown as a position, and the terminal crimping portion imaging position on the return path is shown as a position.

One end of the electric wire W whose terminal coating has been stripped off by the wire stripper 2 moves to a position as the arm 3 rotates. When the camera reaches the position, the light source 8a emits light based on the detection output of the photosensor 8C, and the television camera 8b receives the light. Then, the still image data binarized by the binarization circuit 9 is loaded into the RAM 10 (step S1). This image data will be as shown in FIG. 3, as described above. The CPU 11 receives the import completion notification from the control means C.
reads this image data from the RAM 10 (step S2), and calculates l ₁ and l ₂ by known image recognition (step S3). When l ₁ is obtained, the program retrieves data indicating the allowable range from ROM 12 l _1nio
and l _1nax are read out (step S4), compared with l ₁ (step S5), and if l _1nio < l ₁ < l _1nax , it is determined to be good; otherwise, it is determined to be defective (step S6).
~S8). The same applies to l ₂ . This good/bad judgment signal is given to the control means C, and the control means C
performs predetermined control. For example, the operation of the terminal crimping device may be stopped and an operator may remove defective products, or defective products may be automatically selected.

FIG. 8 shows a flowchart for calculating L by measuring l ₃ and l _4. Steps S9 to S11 up to measuring l ₁ and l ₂ are the same as in the case of FIG. 7 described above. This is the same as steps S1 to S3. After l ₁ and l ₂ are measured at the position, the terminal crimping part of the electric wire W is transferred to the transfer path 7.
It is transferred along the forward path toward the terminal punching machine 5, and after the terminal T is crimped by the terminal punching machine 5, it is again transported to the position along the return path of the transport path 7. When it reaches the position, the light source 8a emits light based on the detection output of the photosensor 8c, and the light is received by the television camera 8b. Then, the still image data binarized by the binarization circuit 9 is loaded into the RAM 10 (step
S12). As mentioned above, this image data is as shown in FIG. 4, and is read out to the CPU 11 (step
S13), l ₃ and l ₄ are determined (step S14). l ₁ ,
Once l _2, l ₃ and l ₄ are obtained, the program calculates the length D of the gripping part Ta of the terminal T (if necessary, the length l from the reference position to the core wire tip position, and the length of the terminal T).
l _T ) is read from the ROM 12 (step S15), and from these data the length L of the covering portion Wa that is left ungrasped by the gripping portion Ta is calculated using the above-mentioned formula (step S16). Furthermore ROM12
The data δ indicating the allowable range and the length Wn of the window portion of the terminal T are read out (step S17) and compared with L (step S18). If δ<L<Wn-δ, it is determined to be good; otherwise, it is judged to be defective. (Step
S19-21). This pass/fail judgment signal is given to the control means C, and the control means C performs the predetermined control as described above.

In the above-described embodiment, measurements (measurement of l ₁ and l ₂ ) before the terminal crimping are always included. Before crimping the terminal, the third
As shown in Figure A, the structure of the wire terminal is very simple, so measurements can be carried out easily and accurately. In addition, since the gripping position by the wire support device 1, which always moves at the same position, is used as the reference position for l ₁ , l ₃ , and l ₄ measurements, the reference position is always a fixed position on the silhouette image, and in addition to the above. moreover,
Measurements can be made easily and accurately. According to the above-mentioned embodiment, by using the values easily and accurately measured in this way, it is possible to easily detect hanging defects and resin bite defects as described above.

FIG. 9 shows an example in which the present invention is applied to a system wire processor instead of the terminal crimping device shown in FIG. As the image processing device, the one shown in FIG. 6 is used, similar to the terminal crimping device shown in FIG. The system wire processor has a conveyor means 14 installed in the left-right direction, and is configured to intermittently move the wire W to be processed to the left in the figure every pitch S. Conveyor means 14
The clamping claw 14a that opens and closes in the left and right direction is attached to the pitch S.
The electric wire W bent into a U-shape is provided at each
The vicinity of both end portions from which the coating has been peeled off is held in a horizontal direction perpendicular to the moving direction of the conveyor means 14. In order from the upstream side of the conveyor means 14, a wire twisting machine 15 for twisting the exposed core wire of the electric wire W, a terminal punching machine 16, and a sorting means 17 for sorting out good products and defective products are attached, all of which are known in the art. The composition is as follows.

_The system wire processor shown in FIG. 9 differs from the terminal crimping device shown in _FIG . Group 18b is upstream of terminal punch 16 (corresponds to the above position)
The above-mentioned
A set of a light source 19a and a television camera 19b for measuring l ₃ and l ₄ is attached downstream of the terminal punching machine 16 (corresponding to the above position) and facing each other across the transfer path. In addition, since the electric wire W is transferred intermittently and the stationary time at the inspection (imaging) position is sufficiently long, a static silhouette image of the terminal crimping part can be captured without using strobe light sources as the light sources 18a and 19a. . Therefore, there is no need to particularly provide a photosensor.

Note that the light sources in the above embodiments include those in which the light emitting part itself, such as a lamp, directly faces the television camera;
For example, it may be as shown in FIG. In the example of FIG. 10A, the light emitted from the lamp house 20 of the light emitting unit is guided by the optical fiber bundle 21 of the light guiding means to a position directly facing the television camera (irradiation position), and then by the diffusion surface 22. It is diffused and illuminates the terminal crimp area. In the example of FIG. 10B, the light emitted by the lamp 23 of the light emitting part is reflected by the mirror 24 of the light guiding means and guided to a position directly facing the television camera (irradiation position), and irradiates the terminal crimping part. .

In addition, in the above embodiment, the electric wire W is
Although a silhouette image of the terminal crimping part is imaged, it is also possible to image only the state (position state) before the terminal crimping and measure only l ₁ and l ₂ .
In this case as well, as described above, it is possible to sufficiently predict hanging defects and resin chewing defects.

The method of determining the length using image recognition means, the length that should be read for each part of the terminal, and the data regarding the allowable range differ depending on the type and size of the electric wire and the type and size of the terminal. By executing an appropriate program according to the selection in the control means C, it is possible to inspect the terminal crimping state even in cases other than the above-mentioned embodiments.

(Effects of the Invention) As described above, according to the present invention, image processing is performed using a silhouette image using transmitted illumination, so that a sufficient light reception level can be obtained regardless of the color of the covering part of the terminal crimped electric wire. Furthermore, even if the position and orientation of the terminal crimping part change slightly, the light reception level does not change, and the quality of the terminal crimping part can be accurately and reliably inspected. Furthermore, since there is no need to provide a condensing lens for projecting light, and there is no need to identify colors, the configuration becomes simple. Moreover, when a silhouette image is captured before the terminal is crimped, or before and after the terminal is crimped, and a predetermined dimension is measured based on the image data obtained by the imaging to inspect the condition of the terminal crimped part, the predetermined As for the dimensions, in the state before terminal crimping, the length l ₁ between the grip position of the terminal crimped electric wire with the insulation peeled off by the wire support device and the insulation peeling position of the terminal crimped electric wire with the insulation peeled off, and the said insulation peeling position. At least one of the lengths l ₂ between the core wire tip position and the terminal crimping position is at least one length, and at least one of the lengths l ₃ and l ₄ between the gripping position and both end positions of the crimp terminal in the state after the terminal is crimped. In order to inspect the condition of the terminal crimping part, l ₁ is determined based on at least one of the measured l ₁ and l ₂ before the terminal crimping.
The terminal crimping condition is determined as good or bad depending on whether it is within a predetermined range or not. After the terminal crimping, at least one of l ₁ and l ₂ and at least one of l ₃ and l ₄ measured above Based on this, the length of the sheathing part of the terminal crimped electric wire that is not gripped by the gripping part of the terminal is determined, and whether or not the length is within a predetermined range is used to judge whether the terminal crimped state is good or bad. It has the following effects. In other words, measurements must be taken before terminal crimping, and since the structure of the wire end is simple before terminal crimping, measurement is easy and accurate, and the wire gripping position by the wire support device, which always moves at the same position, is Since the reference position is used as the reference position, the reference position is always a fixed position on the silhouette image, making measurement easy and accurate. Then, using the values easily and accurately measured as described above, it is possible to easily determine whether the terminal crimping condition is good or bad.

[Brief explanation of the drawing]

1A and 1B are a perspective view and a plan view of the terminal crimping section after terminal crimping, and FIG. 2 is a schematic diagram showing an example of applying the present invention to a terminal crimping device,
Figures 3A and 3B are diagrams showing the terminal crimping part and its silhouette image before terminal crimping, Figure 4 is a diagram showing a silhouette image of the terminal crimping part after terminal crimping, and Figure 5 is a diagram showing each of the terminal crimping parts. Diagram showing dimensions, No. 6
The figure is a schematic block diagram showing an example of an image processing device.
Fig. 7 is a flowchart in the case of l ₁ and l ₂ measurement, Fig. 8 is a flowchart in the case of L calculation, Fig. 9 is a schematic diagram showing an example of applying the present invention to a system wire processor, and Fig. 10A Figures 1 and 10B are diagrams showing an example of a light source. In the figure, W...Electric wire, T...Terminal, 7...Electric wire transfer route, 8a, 18a, 19a...Light source, 8b,
18b, 19b...TV camera.

Claims (1)

[Claims] 1. A method for inspecting a terminal crimped part of a terminal crimped electric wire, in which a terminal is crimped to the terminal part of which the core wire is exposed by peeling off the coating, wherein a predetermined test is performed based on image data obtained by imaging the terminal crimped part. In the device for inspecting the condition of the terminal crimped portion by measuring dimensions, a light source for at least one imaging is disposed on one side of a transfer path of the terminal crimped electric wire held and transferred by a wire support device, and at least One imaging means is disposed facing the light source on the other side across the transfer path to capture a silhouette image of the terminal crimping portion, and this silhouette image is captured before and after the terminal crimping. The predetermined dimensions are determined in the state before the terminal crimping by the gripping position of the terminal crimped electric wire by the wire support device with the sheath removed and the terminal crimping with the sheath removed. The length is at least one of the length l ₁ between the wire sheathing peeling position and the length l ₂ between the sheathing peeling position and the core wire tip position, and in the state after the terminal is crimped, the gripping position is at least one of the lengths l ₃ and l ₄ between the terminal and both end positions of the crimp terminal, and before the terminal is crimped, l is the length based on at least one of the measured l ₁ and l ₂ . ₁ is determined, and whether or not it is within a predetermined range is used to determine whether the terminal crimping condition is good or bad. After the terminal crimping, at least one of l ₁ and l ₂ and l ₃ and l ₄ measured above are determined. The length L of the sheathing part of the terminal crimped electric wire that is left ungrid by the gripping part of the terminal is determined based on at least one of the terminals, and whether the terminal crimping condition is good or bad is determined based on whether or not this is within a predetermined range. A method for inspecting a terminal crimped part of a terminal crimped electric wire, characterized in that: