JP2000346814A - Device and method for inspecting lip seal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device and a method for inspecting a lip by forcibly deforming it at the time of seal inspection to inspect defective parts of a lip seal made of an elastic body. SOLUTION: In this device and method for inspecting a lip seal 1 having a lip 1a made of an elastic body, a transparent jig 3 is pressed against the lip 1a, and this pressed part is projected by a diagonal floodlighting device 4. This is image-recognized by an image pickup device 5 to judge the quality. Thereby a small defect in the lip 1a can be easily detected and checked, enabling the accurate inspection to be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seal inspection method for inspecting a defective portion of an elastic lip seal, and more particularly, to an inspection apparatus and an inspection method capable of automatically inspecting a lip by an inspection machine. For development purposes.

[0002]

2. Description of the Related Art Conventionally, in the case of a lip seal having a lip which comes into contact with a rotating body, such as a rubber product such as an oil seal, it is unavoidable that a flaw such as a molding flaw, an air flaw or a finish flaw is generated in manufacturing. In order to maintain stable sealing performance, inspection of the lip flaw is indispensable. In the inspection of lip flaws, there is a shift from a simple inspection judgment based on visual or finger touch for checking the appearance to a high-precision optical inspection method based on image confirmation by projecting light using an optical device. In the confirmation inspection using an image using the optical imaging device, a subject such as a lip seal is enlarged by a magnifying glass or the like, and the image is recognized by a CCD camera or the like (not shown), or the drawing is explained. Then, as shown in FIG. 3, a method of irradiating the lip 1a contacting the pedestal 7 with light from the light source 6 and detecting a defect of the lip seal 1 by the transmitted illumination is performed.

[0003]

However, an enlarged image confirmation inspection method for enlarging and confirming the lip seal described above, or an inspection method for detecting a defect by applying light to the lip seal 1 shown in FIG. However, there is a drawback that a serious defective portion cannot be accurately determined to be defective as a seal such as undulation, distortion or eccentricity, as well as small scratches. In other words, if the defective cutting scratches or molding scratches are minute, or if the elastic body has the property of restoring the original shape, increase the magnification of the magnifying glass to inspect this. Alternatively, it is necessary to take measures such as increasing the amount of light of the light source 6 to increase its sensing accuracy, or increasing the number of the imaging devices 5 to be installed. It cannot be a countermeasure.

In addition, since the relative shapes cannot be easily compared for inspections such as waviness, distortion, and eccentricity, the reliability of the inspections is low. The purpose of the present invention is
An object of the present invention is to develop an inspection apparatus and an inspection method capable of solving the above-mentioned disadvantages, accurately inspecting a lip made of an elastic body for a shape defect, and performing an automatic inspection.

[0005]

According to the present invention, an elastic body such as synthetic rubber or synthetic resin which is mounted on a rotating part and seals a fluid in the rotating part, as shown in FIG. 1. A device for inspecting a lip seal 1 having a lip 1a formed by: a seal grip portion 2 capable of detachably gripping the lip seal 1, and a flat surface made of a transparent material and adapted to the lip 1a. Transparent jig 3
And an oblique projection lighting device 4 for irradiating the inspection region of the lip 1a obliquely, and an imaging device 5 for capturing an image of the inspection region.
After the transparent jig 3 is pressed against the lip 1a and brought into contact with the lip 1a, the obliquely illuminating device 4 is illuminated from the oblique direction through the transparent jig 3 and placed on the side where the light is reflected. It is characterized in that the image of the lip 1a is recognized by the imaging device 5.

A method of inspecting a lip seal 1 having a lip 1a formed of an elastic material such as synthetic rubber or synthetic resin for sealing a fluid, wherein the inspection device is a lip seal 1 as shown in FIG. Seal gripper 2 for gripping
And a transparent jig 3 pressed against the lip 1a of the lip seal 1.
And an oblique light illuminating device 4 that emits oblique light with respect to a plane of contact with the lip 1a, and an imaging device 5 that captures an image. The lip seal 1 is fixed by the seal gripping portion 2, As shown in FIG. 2, the lip 1a of the lip seal 1 is brought into pressure contact with the transparent jig 3 to appropriately deform the lip 1a. The oblique light projecting illumination device 4 set at an angle from the oblique direction to reflect light is radiated through the transparent jig 3 to form a visible image of the contact portion, and the image of the lip 1a is taken by the imaging device 5 installed on the reflection side. Is recognized, and the defect of the lip 1a is determined.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the inspection for judging the quality of the lip seal 1 as described above, the present invention presses the transparent jig 3 against the lip 1a of the lip seal 1 to form a contact image, thereby forming a flaw or a distorted portion. Inspection apparatus and inspection method for expanding or increasing the problem shape of the above, irradiating the light from the oblique direction through the transparent jig 3 to form a visible image, and recognizing the image with the imaging device 5 and determining whether or not the image is acceptable. As shown in FIG. 1, the inspection device includes a seal gripping portion 2 for gripping a lip seal 1, a transparent jig 3 pressed against a lip 1a, and an oblique floodlighting device 4 for irradiating obliquely. And an imaging device 5 for capturing an image of the inspection site.

On the other hand, in the inspection method, as shown in FIG. 2, a pressure is applied to the lip 1a by the pressing action of the transparent jig 3 so that the lip 1a is deformed and spread, and the oblique projection illumination device 4 irradiates the light from obliquely. In the case where there is a flaw or the like, a situation is created in which the defect shape of the defective portion can be clearly grasped as an image, and this is confirmed by the image pickup device 5 to make a pass / fail decision, whereby accurate inspection is achieved.

[0009]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
First, the lip seal 1 to be inspected is placed on the seal gripping portion 2 and fixed, and then the transparent jig 3 is brought into pressure contact with the lip 1 a of the lip seal 1. At this time, the interference of the lip 1a with respect to the transparent jig 3 is set to about 1 to 30%, and the lip 1a is set at a position having an angle for pushing out a defect such as a cut flaw. Next, the oblique projection light illuminating device 4 that irradiates the contact portion of the lip 1a from the oblique direction is arranged in relation to the transparent tool 3 at an angle at which the light is totally reflected and enters the image pickup device 5.
By irradiating this light, the defect is determined based on a contact mark image formed on a portion of the lip 1a in close contact with the transparent jig 3.
(At the defective portion, light is reflected in a different direction, so it is seen as a black portion.) When the lip 1a is contacted, the lip 1 is rotated by rotating the seal holding portion 2 while holding the lip seal 1.
The entire circumference of the lip 1a can be confirmed, and the sliding of the lip 1a to the transparent tool 3 does not spread the defective portion of the lip 1a, thereby facilitating the determination.

[0010]

According to the above configuration, the following excellent effects can be obtained. According to the present invention, small defects (scratch, crack, deformation, etc.) of the lip 1a such as cut scratches and cracks of the lip 1a can be easily detected and confirmed without zooming up by pressing the transparent jig 3 and obliquely projecting light. This makes it possible to easily inspect a lip seal which cannot be inspected using transmitted illumination and is difficult to detect a defect. In addition, for a shape defect such as undulation, distortion or eccentricity, the contact image of the lip 1a clearly shows a change in the shape as a deformed image, so that the inspection accuracy is high. Therefore, the inspection can be performed with high accuracy using the simple imaging device 5 and the automatic inspection can be performed.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an embodiment of the present invention.

FIG. 2 is an enlarged partial sectional view of FIG.

FIG. 3 is a schematic sectional view showing a conventional inspection method without using the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lip seal 1a Lip 2 Seal holding part 3 Transparent jig 4 Oblique projection lighting device 5 Imaging device 6 Light source 7 Pedestal

Claims (2)

[Claims] 1. A lip seal inspection device having a lip formed of an elastic body such as synthetic rubber or synthetic resin for sealing a fluid, wherein the seal gripping portion grips the lip seal and a transparent material. Consisting of a transparent jig having a flat surface suitable for the lip, an oblique floodlighting illumination device that illuminates the lip inspection site, and an imaging device that captures an image,
Affixing the lip seal to the seal gripping portion, and pressing the transparent jig against the lip to make contact therewith, then irradiating the pressing contact portion of the lip with light through the transparent jig from an oblique direction with the oblique projection lighting device, A lip seal inspection device, wherein a lip image is recognized by an imaging device installed on the light reflection side. 2. A method for inspecting a lip seal having a lip formed of an elastic body such as synthetic rubber or synthetic resin for sealing a fluid, wherein the inspection device comprises: a seal gripping portion for gripping the lip seal; A transparent jig in contact with the lip, an oblique projection lighting device that emits light from an oblique direction, and an imaging device that captures an image.The lip seal is fixed with the seal holding portion, and the lip is attached to the transparent jig. After the contact image is made visible by pressing the lip of the seal, the pressed contact portion of the lip is illuminated from the oblique direction through the transparent jig with the oblique light illuminating device, and installed on the reflection side of the light. Lip seal inspection method for recognizing a lip image by a picked-up imaging device and performing a defect determination.