JPH0711549B2 - Crimping defective terminal detection method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for detecting a crimping defective terminal when a crimping terminal is attached to an electric wire terminal.

[Prior Art] To attach a crimp terminal to the end of an electric wire, the wire barrel of the crimp terminal is crimped to the core wire of the electric wire terminal, and the insulation barrel is crimped to the insulating resin coating portion of the electric wire terminal. Among the many crimp terminals, there may occur terminals such as a crimp failure of the core wire portion and a crimp failure of the resin coating portion.

Such a crimp terminal is a terminal row in which a large number of terminals made of conductive metal plates are connected by a carrier 21 as shown in FIGS.
A wire barrel 23, an insulation barrel 24, and a contact terminal portion 25 are provided on the crimping terminal 20 of 22. This terminal row 22 is fed to a continuous crimping device, the terminal 20 is cut from the carrier 21, and as shown in FIG. 7A. The wire barrel 23 is crimped to the core wire W1 of the electric wire terminal, and the insulation barrel 24 is crimped to the insulating resin coating portion W0.

Thus, the crimp terminal 20 attached to the end of the electric wire is in a state as shown in FIG. 7A when it is normally crimped, but becomes in a state as shown in B, C and D in the same figure in the case of improper attachment. Figure B
Is a so-called "core wire spill" in which a part of the core wire W1 of the wire end W2 protrudes from the wire barrel 23 and is in a so-called "core wire spill" state. In the same figure C, the wire barrel 23 is not crimped onto the core wire W1 and is covered with an insulating resin coating W0. This is a so-called "resin bite" state in which it is crimped to the end of the wire. In the same figure D, the tip of the core wire W1 falls below the wire barrel 23, and the insulation barrel 24 ends at the end of the insulating resin coating W0. It is in the state of "core wire sagging", where it was crimped to the wire W1 without being crimped to.

As a method for detecting the crimping failure state of the crimping terminal attached to the wire end as described above, the applicant of the present invention has proposed that a pressure sensor is attached to the embossing ram of the terminal crimping device and the crimping generated on the embossing ram at the time of crimping the terminal. Japanese Patent Application No. Sho 62, which detects the distortion caused by the reaction force and compares the temporal change pattern of the detected output signal waveform with the temporal change pattern of the signal waveform during normal crimping to detect crimping defects. -Developed a method for detecting terminal crimping defects in 114423 terminal crimped wires.

[Problems to be Solved by the Invention] Even with a standard normal crimp terminal that is compared with the crimp terminal to be inspected as described above, the temporal change pattern of the crimp force signal waveform of all the terminals is not always uniform. There is some variation in normal products, especially "core wire spill"
In the case of the abnormal shape as shown in FIG. 7B, if there are about 1 to 2 spills of a part of the core wire W2, the difference between the waveform pattern of the defective crimp terminal and the waveform pattern of the normal crimp terminal is 8
Since it is small as shown in the figure, it is difficult to distinguish the two.

FIG. 8 shows a temporal change pattern of the waveform of the crimping detection signal in the case of "core wire spill" in the side feed type crimping terminal. The solid line waveform m is a reference waveform pattern to be compared. Of the crimping force detection signal waveform, the waveform n of the dotted line shows the temporal change pattern of the crimping force detection signal waveform of the crimp terminal to be inspected, and the horizontal axis shows the elapsed time of the waveform change (msec). , The vertical axis represents the crimping force (Kgf).

Like this waveform pattern, the waveform 11 of the behavior when the terminal 20 is disconnected from the carrier 21 and the waveform T2 of the behavior when each pressing of the wire barrel and the insulation barrel become one continuous waveform pattern, and the detection signal Since the maximum level difference d between the dotted waveform and the normal reference waveform is extremely small, it is difficult to determine the difference between the normal crimp terminal and the abnormal crimp terminal by simply comparing the temporal change patterns of such waveform. There is a problem that is.

Therefore, the present invention provides a method for detecting a crimped defective terminal which can accurately determine even a terminal crimped state having a small difference between the corrugated pattern of a defective crimped terminal and the corrugated pattern of a normal crimped terminal as described above. Is provided.

[Means for Solving the Problems] In order to solve the above problems, the present invention crimps a wire barrel of a crimp terminal having a wire barrel and an insulation barrel to a core wire of an electric wire terminal to insulate the insulation barrel. When crimping to the resin coating and crimping to the wire end, the load sensor detects the crimping force of the wire barrel and the insulation barrel separately, and the waveform pattern determination circuit for each crimping force detection signal of the wire barrel and the insulation barrel 40 , 46, the crimping force detection signal waveform patterns of the wire barrel and the insulation barrel are compared with the crimping force waveform patterns of the normal crimping state, and the crimping failure terminal is caused by the difference in the temporal change pattern of the crimping force. Is detected.

[Operation] The wire barrel of the crimp terminal is crimped to the core wire of the electric wire terminal with the pressing blade mold 3A, and the insulation barrel is pressed with the blade mold.
When pressure is applied to the insulating resin coating with 3B, a reaction force equal to each pressure force is generated, and correspondingly, distortion is generated in each of the pressing blade dies 3A and 3B.

Therefore, the load of each strain is detected to obtain a detection signal of each crimping force. The detection signals of the crimping force of each of the wire barrel and the insulation barrel are input to the different waveform pattern determination circuits 40 and 46, and the respective waveform patterns of the respective detection signals are crimped in the normal crimping state. And the difference in the temporal change pattern of the waveform is determined to detect the defective crimping force. As a result, each waveform pattern of the behavior when the wire barrel is pressed and the behavior when the insulation barrel is pressed (waveform of T2 in Fig. 8) is obtained separately, and even one or two "core wire spills" can be accurately detected. Further, the classification of defective states such as "core wire spillage", "resin bite", "core wire breakage", "core wire sagging", etc. is determined.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a terminal crimping device used in the method of the present invention, FIG. 2 is a side view thereof, and 1 is an applicator,
This reciprocates up and down by an appropriate drive means 2 such as a toggle device to move the blade die 3 for pressing the crimping terminal attached to the lower end of the applicator up and down. Reference numeral 4 denotes guide frames on both sides of the applicator 1 which moves up and down.

The pressing blade die 3 presses the crimp terminal by the lowering of the applicator 1 and crimps it to the electric wire terminal. As shown in the side view of FIG. The wire barrel pressing blade die 3A for pressing (FIGS. 5, 6, and 7) and the insulation barrel 24
Insulation barrel pressing blade dies 3B for pressing are arranged at the lower end of the applicator 1 in the front-rear direction, and each of the blade dies 3A, 3B is formed of a substantially plate-shaped member. A punch for cutting the carrier 21 of the terminal row 22 is provided at the lower end of the applicator 1.
Install 3C.

5 is a terminal crimping base, and crimping terminals are mounted on this terminal crimping base 5.
20 is placed and pressed by the pressing blade die 3 to be crimped to the wire end.

Reference numeral 6 denotes a terminal distribution lever, which pivotally supports the upper end portion thereof, fits the tip of an arm 8 which moves up and down together with the applicator 1 into a groove 9, and when the applicator 1 moves up and down, the terminal distribution lever 6
Oscillates to the left and right, and the tip of the rod 10 at the lower end moves to the left and right, cutting the crimp terminals 20 one by one from the terminal row 22 in which a large number of terminals are bound together in a strip shape and placing them on the terminal crimping table 5. Distribute.

Reference numeral 11 is a tray for discharging the terminal portion of the electric wire with the terminal to which the crimp terminal 20 has been attached.

When the applicator 1 is lowered and the pressing blade die 3 crimps the crimp terminal 20 on the terminal crimping base 5 to the wire end, a reaction force equal to this crimping force is generated in the pressing blade die 3. When the wire barrel 23 is crimped to the core wire of the electric wire end by the crimping force Pa by the wire barrel pressing blade die 3A, a reaction force Pa equal to the crimping force Pa is generated in the wire barrel pressing blade die 3A, and this reaction force
Distortion occurs in the wire barrel pressing blade die 3A corresponding to Pa. Further, when the insulation barrel 24 is crimped by the insulation barrel pressing blade die 3B to the insulating resin coating portion with the crimping force Pb, a reaction force Pb equal to the crimping force Pb is generated in the insulation barrel pressing blade die 3B, and this reaction Power
Pb corresponding strain is the blade type 3B for pressing the insulation barrel
Occur in. A reaction force is generated in the punch 3C when the carrier 21 of the terminal row 22 is cut by the punch 3C.

Therefore, as shown in the third illustration, the wire barrel pressing blade die 3A
And, the blade barrel 3B for pressing the insulation barrel is equipped with the load sensors 30 and 35 for detecting the crimping force, which are composed of pressure sensors such as load cells using strain resistance elements, and each blade die 3A and the blade die 3B when crimping the terminal. The above-mentioned distortion that occurs in 1) is detected.

That is, the load sensor 30 for detecting the wire barrel crimping force
Is a pressure sensor 31 on the surface of the wire barrel pressing blade die 3A.
32 is mounted and pressure sensors 33 and 34 are mounted on the back side, and the load sensor 35 for detecting the insulation barrel crimping force is the blade type for pressing the insulation barrel.
The pressure sensors 36 and 37 are attached to the front surface of 3B and the pressure sensors 38 and 39 are attached to the back surface of the 3B.

The pressure sensors 31, 32, 33, 34 forming the load sensor 30 for detecting the wire barrel crimping force and the pressure sensors 36, 37, 38, 39 forming the load sensor 35 for detecting the insulation barrel crimping force are respectively A bridge is formed as shown in FIG. 4, and the bridge is connected to the waveform pattern determination circuit 40 for the crimping force detection signal of the wire barrel and the waveform pattern determination circuit 46 for the crimping force detection signal of the insulation barrel.

The waveform pattern determination circuit 40 of the wire barrel crimping force detection signal is a strain amplifier 41 which receives the output of the bridge of the load sensor 30, an A / D converter 42, a comparator 43, a memory 44 and a C.
The waveform pattern determination circuit 46 including the PU 45 and the insulation barrel crimping force detection signal also includes a strain amplifier that receives the output of the bridge of the load sensor 35, an A / D converter, a comparator, a memory, and a CPU.

In the device configured as described above, the applicator 1
Move up and down and the wire barrel pressing blade die 3A and the insulation barrel pressing blade die 3B are placed on the terminal crimping base 5 to connect the wire barrel 23 and the insulation barrel 24 of the crimping terminal to the core wire of the electric wire terminal and the insulating resin. When pressure is applied to the covering portion, the load sensor 30 for detecting the wire barrel crimping force detects the crimping force and the bridge outputs a detection signal, and the load sensor 35 for detecting the insulation barrel crimping force detects the crimping force. For detection, the bridge outputs a detection signal.

The detection signal output from the bridge of the load sensor 30 for detecting the wire barrel crimping force is input to the amplifier 41 of the waveform pattern determination circuit 40 of the wire barrel crimping force detection signal,
The output signal level of this amplifier is compared with the reference level by the comparator 43, and if it is equal to or higher than the reference level, a trigger signal is output,
A level trigger is applied to the A / D converter 42, and this A / D converter samples the detection signal of the output of the amplifier 41, A / D converts it and stores it in the memory 44 in time series. Of the normal crimping force waveform stored in the memory 44 (the pattern of the detection signal waveform corresponding to the wire barrel crimping force of the terminal in the normal crimping state) stored in the memory 44 and the detection signal waveform pattern is normal. It is determined whether or not there is an abnormality, and if there is an abnormality, an abnormality determination signal is output.

The reference level of the comparator is set to a voltage level that promotes the rise of the waveform generated when the terminals are crimped, and all level signals above that level are sampled. The sampling cycle varies depending on the operating time of the applicator 1, but when the crimping cycle is 0.8 seconds and the crimping time is about 80 msec, the waveform is 400
If you divide it into equal parts, a waveform with good reproducibility can be obtained.
Sampling at a cycle of.

Further, the detection signal output from the bridge of the load sensor 35 for detecting the insulation barrel crimping force is also input to the waveform pattern determination circuit 46 of the insulation barrel crimping force detection signal in the same manner as described above, and the amplifier and the A / D converter are provided. The comparator, the memory, and the CPU compare the detection signal waveform pattern with the normal waveform pattern, determine whether the detection signal waveform pattern is normal or abnormal, and output an abnormality determination signal if the detection signal waveform pattern is abnormal.

A load sensor for detecting the wire barrel crimping force as described above
30 and the load sensor 35 for detecting the crimping force of the insulation barrel detect the crimping force of the wire barrel and the crimping force of the insulation barrel separately, and the waveform pattern determination circuits 40 and 46 of the crimping force detection signals of the respective wires are wired. The waveform patterns of the crimping force detection signals of the barrel and the insulation barrel are individually judged to be normal or abnormal.
The detection signal waveform pattern of the crimping force when the crimping attachment state is normal is as shown in FIGS. 9 (A) and 9 (B). The horizontal axis represents the elapsed time of waveform change (msec), the vertical axis represents the crimping force (Kgf), (A) shows the detection signal waveform pattern ma of the normal crimping force of the wire barrel, and (B) shows the normal insulation. The detection signal waveform pattern mb of the pressure force of the aeration barrel is shown.

10 to 13 show the waveform patterns of the detection signal when the crimping and mounting state is bad. When a "core wire spill" occurs when a part of the core wire of the electric wire terminal protrudes from the wire barrel, for example, the core wire 7 When one or two of the books spill from the crimping of the wire barrel, it becomes like the dotted line waveform pattern na in FIG. 10 (A).

Detection signal waveform pattern of normal crimping force of wire barrel
ma is shown as a comparison reference waveform pattern by a solid line, and when this is compared with the dotted line waveform pattern na of "core line spill",
Since the ratio with respect to the peak level is large and the difference greatly appears, it is easy to determine that the "core spill" has occurred, and even if the "core spill" is 1 or 2, it can be accurately detected.

In this case, if the crimping state of the insulation barrel to the insulating resin coating is normal, the crimping force detection signal waveform pattern nb is the normal insulation barrel crimping force detection signal waveform pattern as shown in FIG. 10B. nb
(Same as FIG. 9B) and no difference occurs.

When the wire barrel is not the core wire but the "resin bite" in which the insulating resin coating end is crimped, the detection signal waveform pattern of this wire barrel crimping force is the dotted waveform pattern pa of Fig. 11 (A). When this is compared with the detection signal waveform pattern ma of the normal crimping force of the wire barrel, the difference between the crimping force and the waveform pattern of the elapsed time of the waveform change is remarkable, and it is easy to determine whether "resin bite" has occurred. Is.

In this case, if the crimping state of the insulation barrel against the insulating resin coating is normal, the detection signal waveform pattern nb is the same as the detection signal waveform pattern mb of the normal insulation barrel crimping force as shown in FIG. 11 (B). There is no difference.

In the case of "core wire break", the detection signal waveform pattern of the wire barrel crimping force becomes like the dotted line waveform pattern qa of Fig. 12 (A), and compare this with the detection signal waveform pattern ma of the normal crimping force of the wire barrel. Then, the difference between the two is clear, and it is easy to determine the occurrence of "core wire break". At this time also, the crimping state of the insulation barrel is normal,
The detection signal waveform pattern nb coincides with the detection signal waveform pattern mb of the normal crimping force as shown in FIG. 12 (B).

No. 7 is the crimping failure of the insulation barrel.
As shown in FIG. D, the tip of the core wire W1 is lower than the wire barrel 23 and the insulation barrel 24 is covered with an insulating resin.
This is the case of "core wire sagging" in which the end of W0 is crimped to the core wire W1 without crimping, and the detection signal waveform pattern of the insulation barrel crimping force at this time is the 13th
It becomes the dotted line waveform pattern nr of FIG.

Comparing this dotted line waveform pattern nr with the detection signal waveform pattern mb of the normal crimping force of the insulation barrel, the difference between the peak levels of both waveform patterns is large, and the difference is clear, and the determination of "core wire sagging" occurs. It's easy.

At this time, the wire barrel also has a crimping failure, and the detection signal waveform pattern of the crimping force becomes like the dotted line waveform pattern qa in FIG. 13 (A), which is different from the dotted line waveform pattern qa in FIG. 12 (A). Similarly, it is easy to determine the crimping failure.

Each crimping state of the wire barrel and insulation barrel of the terminal crimped to the wire end as described above is detected, and the waveform pattern of the detection signal is compared with the detection signal waveform pattern of the normal crimping state to determine the crimping force. Whether it is normal or abnormal can be accurately and quickly determined, and at the same time, it can be determined whether the type of crimping failure is "core wire spill", "resin bite", "core wire break", or "core wire sag". In the case of an abnormality, an abnormality determination signal is output.

The output abnormality determination signal is input to an abnormality detection / informing device such as an alarm lamp or a terminal crimping device to notify the occurrence of a defective product, count the types of defective condition, and discharge the defective product.

The load sensors 30 and 35 that detect the crimping force between the wire barrel and the insulation barrel are not installed on the wire barrel pressing blade mold 3A and the insulation barrel pressing blade mold 3B as described above, but instead, on the terminal crimping base 5 The wire barrel receiving portion and the insulation barrel receiving portion may be provided. Further, the method of the present invention is applied not only to the side-feed type terminal as described above but also to the end-feed type terminal.

[Effects of the Invention] As described above, the present invention detects the crimping force of the wire barrel and the insulation barrel separately and compares the waveform pattern of the detected signal with a normal waveform pattern to obtain a temporal change pattern of both waveforms. Since the defective terminal crimping state is detected based on the difference between the two, it is possible not only to accurately detect one or two core wire spills, but also to discriminate even the type of defective state, and whether the crimping state is good or bad. Can be determined extremely accurately and quickly.

[Brief description of drawings]

FIG. 1 is a front view of an embodiment of an apparatus for carrying out the method of the present invention, FIG. 2 is a side view thereof, FIGS. 3A and 3B are schematic views of a pressing blade die, and FIG. 4 is a crimping force. FIGS. 5 and 6 are front and side views of a terminal row, FIGS. 7A, B, C and D are views showing a crimped terminal, and FIG. 8 is a conventional view. FIG. 9 to FIG. 13 are waveform diagrams of the present invention, and FIGS. 9 to 13 are waveform diagrams of the present invention. 20: Crimp terminal 23: Wire barrel 24: Insulation barrel 30: Wire barrel Crimping force detection load sensor 35: Insulation barrel Crimping force detection load sensor 40, 46: Waveform pattern judgment circuit

Claims (1)

[Claims] 1. A crimping force of a wire barrel and a crimping force of an insulation barrel of a crimping terminal to be crimped to an end of an electric wire are separately detected, and a waveform pattern of a detection signal of each crimping force is a waveform pattern of a normal crimping force. A method for detecting a crimping defective terminal, which is characterized by detecting a crimping defective terminal.