JP2910520B2 - Rubber stopper inspection equipment - Google Patents

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 a rubber plug used for a waterproof connector, for example.

[0002]

2. Description of the Related Art Heretofore, a connector called a waterproof connector has been known as a connector used in a place where waterproofing is required. In this one, in order to ensure the sealing property between the inserted electric wire and the housing,
A rubber stopper fitted to an electric wire is used. A general configuration of a rubber plug often includes a cylindrical portion into which an electric wire is closely inserted and a plurality of sealing edges projecting in a flange shape on the outer peripheral surface of the cylindrical portion.

[0003] Incidentally, since the waterproof connectors naturally dislike the entry of water into the interior of the housing, all the rubber stoppers are checked for defects. Examples of defects include underfill and burrs. Since these directly impair the sealing property, such rubber stoppers must be reliably removed. In some cases, foreign matters and dirt are attached to the rubber stopper. Depending on the type of the adhered substance, it is considered that the sealing property is deteriorated with time due to the deterioration of the rubber plug, so it can be said that such a rubber plug should also be removed.

[0004] However, the conventional inspection method for the rubber stopper has been such that an operator grasps the entire body with tweezers or the like and visually judges the whole.

[0005]

As described above, despite the fact that the conventional inspection method is a manual operation, many rubber stoppers having a diameter of several millimeters make it difficult to carry out a knob operation and improve the operation efficiency. Hard to let. In addition, in the visual inspection, the oversight and the determination of quality may be ambiguous, and the removal of defective products cannot be ensured.

The present invention has been devised in view of the above problems, and has as its object to provide a method for inspecting a rubber plug, which can improve the working efficiency and can reliably determine the quality. It is to be.

[0007]

In order to achieve the above-mentioned object, the present invention has a structure in which a plurality of sealing flanges having a cylindrical portion which can be fitted to an electric wire and having a predetermined interval on an outer peripheral surface thereof are provided. An inspection device for a rubber stopper having a protruding edge, wherein the chucking means clamps between the sealing flange edges from the side to hold the entire rubber stopper in a reversible manner, and is held by the chucking means. A visual sensor that is disposed substantially on the axis of the rubber plug in a state of recognizing the rubber plug, and an image processing unit that processes image data from the visual sensor to determine pass / fail. It is characterized by having.

[0008]

The rubber stopper to be inspected is clamped by the chucking means and held below the visual sensor.
The visual sensor detects the planar shape of one end surface of the rubber plug or the dirt condition of the end surface as an image and outputs the image to the image processing unit. Subsequently, the rubber stopper is reversed by the reversing operation of the chucking means, and a detection operation for the situation on the opposite side of the rubber stopper is performed. In the image processing unit, the quality is determined based on the detected image data, and the quality is determined.

[0009]

The effects of the present invention are as follows. Since the rubber stopper is held by the chucking means, the work efficiency of the operation can be improved by eliminating the need for the operator to perform a picking operation. In addition, since the inspection is performed by the visual sensor and the image processing unit, there is no oversight, and the quality judgment is reliable.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying the present invention will be described below in detail with reference to the drawings. FIG. 1 shows an inspection system according to the present embodiment. A parts feeder 2 is installed on a base plate 1, and two branched conveying paths 2a are connected to a downstream end thereof. It can be sent in two rows.
At the end of the transport path 2a, the rubber stopper 3 is held in a vertical position by a holding unit (not shown) for transfer to the chucking device 4 (see FIG. 4). Further, a pair of left and right index tables 5 are arranged on both sides of the end of the transport path 2a, and the inspection of the rubber stoppers 3 proceeds in each of the two tables 5 in parallel.

In both index tables 5, the following four steps are set. That is, a step of picking up the rubber stopper 3 from the transport path 2a, a first inspection step of checking the contour shape of both end faces of the rubber stopper 3, a second inspection step of checking whether or not dirt or foreign matter is attached to both end faces, There is provided a discharging step of discharging to a sorting path 6 for sorting based on the determination result. And
In order to determine the position at which each of these steps is performed, both index tables 5 are connected to a driving device (not shown) and are rotatable angularly at regular intervals of 90 °. Further, in order to transfer the rubber stopper 3 between these processes, four chucking devices 4 are arranged on the index table 5 at intervals of 90 °.

As shown in FIG. 3, each chucking device 4 has a rotary actuator 7 fixed on an index table 5, and a reversible clamp 8 for holding the rubber stopper 3 is mounted on each of them. ing. The rotary actuator 7 is connected to an air source (not shown) so that the supply and discharge of the rotary actuator 7 can cause the clamp 8 to perform normal rotation and reverse operation. The clamp 8 has a pair of chuck claws 9 and 10 facing each other so as to be able to expand, and both chuck claws 9 and 10 are connected to an air cylinder (not shown) and can be opened and closed. As shown in FIG. 5, each of the chuck claws 9 and 10 has a semicircular recess formed at the center of the opposing piece, and the rubber stopper 3 is closed when the chuck claws 9 and 10 are closed. Are formed as clamp edges 9a and 10a for clamping the valley portion along the entire circumference. Further, in one of the chuck claws 9, a positioning edge 9 b that engages with the lower surface of the mating chuck claw 10 on both sides of the clamp edge 9 a
Are formed overhanging. By doing so, the displacement of the chuck claws 9, 10 can be restricted, so that the rubber stopper 3 can be reliably held even when the clamp 8 performs the normal rotation / reversal operation.

Both the first and second inspection processes have the same configuration of the inspection apparatus. That is, as shown in FIG. 2, the index table 5 is located at a position corresponding to both inspection steps.
A camera 11, which is a visual sensor for inspecting the appearance of the rubber stopper 3, is disposed on the outer peripheral side of the camera. This camera 1
Numeral 1 is supported by supporting legs 12 fixed on the base plate 1 and is arranged substantially coaxially with the rubber stopper 3. In this example, a camera using a CCD image pickup device is used as the camera 11, and the camera 11 captures an image by projecting one end face of the rubber plug 3 from above. The camera 11 is connected to an image processing unit (not shown), and the quality is determined by the following processing, for example. However, in the first inspection step, the underfill inspection and the burr inspection are performed by, for example, the line method described below, and in the second inspection step, the dirt inspection is performed by, for example, the window method.

In either system, image data captured by the camera 11 is output to an image processing unit. Then, in order to clearly distinguish the end face area of the rubber plug 3 from the background area, a predetermined threshold value is used.
A value process is performed to change the pixel group in the end face region to a white value and the pixel group in the background region to a black value. In the binarization processing, a ring light 13 is attached around the camera 11 to enhance the contrast between the end face shape of the rubber plug 3 and the background, and the rubber plug 3 is lit.

The line method is a method in which a limit line of a contour line to be a good rubber stopper is set on image data subjected to binarization processing, and the contour line of the rubber stopper under inspection is set from the line. This is a method of determining whether the data is protruding. Specifically, in the case of the underfill inspection, as shown in FIG. 6, the underfill limit lines a and b are set inside along the contour of the end face shape of the rubber plug 3, and the limit lines a and b are set.
The background area (the shaded area in FIG. 6) is between the limit lines a and b between b.
The determination is made based on whether or not it is beyond the limit. For example, in FIG. 6A, since the background area does not exceed the underfill limit lines a and b, it is determined that there is no underfill and it is a good product.
In (B), since the background area is beyond the underfill limit lines a and b, it is determined that there is underfill. In the case of the burr inspection, as shown in FIG. 7, a burr limit line c is set outside along the contour of the end face shape of the rubber plug 3, and the burr limit line c is moved beyond the burr limit line c. End face area (FIG. 7)
Is determined based on whether or not the white area of the image is protruding. For example, in FIG. 7A, the end surface area of the rubber plug 3 does not exceed the burr limit line c, so that it is determined to be a good product without burr. In FIG. 7B, the end surface area of the rubber plug 3 is set to the burr limit line. Since it protrudes beyond c, it is determined that there is a burr.

In the first inspection step, the rubber stopper 3
After the above-described processing is performed on one end face, the same processing is performed on the other end face by reversing the clamp 8. Next, the window method adopted in the second inspection step is that a reference range is set in advance on the binarized image data, and the number of pixels having a certain value within the range is determined. If the counted number does not reach a certain number of pixels, it is determined that there is dirt. Specifically, as shown in FIG. 8, a slightly smaller reference range (a ring-shaped area surrounded by inner and outer broken lines in FIG. 8) having the same shape as the end face shape of the rubber plug 3 is set. Count the number of pixels of the white value. At this time, if dirt or foreign matter is attached to the surface of the rubber plug 3 (see FIG. 8B), when the binarization process is performed, the dirt portion d becomes a black value like the background region. Since it appears in the reference range, the result of counting the number of pixels of the white value in the reference range is smaller than the number of pixels in the reference range when there is no stain, and it is determined that there is stain.

On the other hand, as shown in FIG. 1, the both sorting paths 6 are provided with a sorting plate 6a for sorting and discharging the rubber plugs 3 according to the quality. The sorting plate 6a is slidably mounted along the length of the sorting path 6, and its operation is controlled based on the determination result from the image processing unit. Sorting path 6
The one end side (the right end side in FIG. 1) is a non-defective product discharge side, and the other end side (the left end side) is a defective product discharge side. is set up. When receiving the rubber plug 3 from the chucking device 4, the sorting plate 6 a waits near any end from below the chucking device 4 based on a command from the image processing unit, and specifically, as a non-defective product If it is determined, as shown in FIG. 1, the sorting plate 6a is deviated to the defective product discharge side and waits, and if it is determined to be defective, it moves to the non-defective product discharge side, and Wait here. The above-mentioned dropping into the receiving box is performed when an appropriate amount of non-defective or non-defective products are accumulated on the sorting path 6a. This can be performed, for example, by providing a timer device and moving the selection plate 6a to near the end when the set time has elapsed.

According to the above structure, the rubber stopper 3 conveyed from the parts feeder 2 and held in a vertical position is held by closing the chuck claws 9 and 10 from the side thereof. Is done. This gripping means is performed by clamping the clamp edges 9a, 10a of the chuck claws 9, 10 to the valleys of the rubber plug 3, so that the rubber plug 3 is exposed with the seal edge exposed, that is, the seal edge. Does not hinder the shape inspection. Also,
At the time of clamping, the positioning edge 9b is engaged so as to overlap the lower surface of the opposing chuck claw 10, so that even if the reversing operation is performed, the mutual positions are not shifted and the rubber stopper 3 can be reliably clamped. it can. Therefore, even a rubber stopper 3 as small as several millimeters can be grasped accurately,
Moreover, since the rubber stopper 3 is not dropped during the inspection, the working efficiency can be greatly improved as compared with the manual operation using the conventional tweezers.

Further, the inspection of the rubber plug 3 is performed based on the image data of the end face of the rubber plug 3 by the camera 11 in the second and third inspection steps. There is no oversight, and the quality judgment is also reliable.

In the present invention, various modifications are possible.
The underfill inspection and burr inspection in the first inspection step, or the dirt inspection method in the second inspection step are not limited to the line method and the window method shown in the present embodiment.

[Brief description of the drawings]

FIG. 1 is a top view showing an entire embodiment of the present invention.

FIG. 2 is a side view showing the whole;

FIG. 3 is a top view showing a chucking device.

FIG. 4 is a side view showing a clamped rubber stopper.

FIG. 5 is a top view showing a chuck claw;

FIG. 6 is image data subjected to a binarization process in an underfill inspection.

FIG. 7 is image data subjected to binarization processing in a burr inspection;

FIG. 8 is image data subjected to binarization processing in a stain inspection.

[Explanation of symbols]

 3 rubber stopper 4 chucking device 11 camera (visual sensor)

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-102050 (JP, A) JP-A-6-229928 (JP, A) JP-A-6-129539 (JP, A) JP-A-63- 61149 (JP, A) JP-A-3-33644 (JP, A) JP-A-57-6307 (JP, A) JP-A-62-46204 (JP, A) JP-A-6-51862 (JP, U) (58) Field surveyed (Int. Cl. ⁶ , DB name) G01N 21/84-21/90

Claims (1)

(57) [Claims] 1. An inspection device for a rubber plug having a cylindrical portion which can be fitted onto an electric wire and having a plurality of sealing flange edges formed at a predetermined interval on an outer peripheral surface thereof. A chucking means for clamping the entire space between the flange edges from the side to reversibly hold the rubber stopper, and a rubber stopper which is disposed substantially on the axis of the rubber stopper held by the chucking means to recognize the rubber stopper. A rubber stopper inspection device, comprising: a visual sensor that performs visual inspection; and an image processing unit that determines image quality by processing image data from the visual sensor.