JP3491223B2 - Inspection device and inspection method for rotary seal - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for inspecting the sealing performance of a rotary seal having a lip made of an elastic material, and more specifically, an inspecting apparatus and an inspecting method that enable automatic inspection of a lip by an inspecting machine. Intended for development.

[0002]

2. Description of the Related Art Conventionally, in a rubber product such as a seal, for example, a rotary seal having a lip that comes into contact with a rotating body, a flaw such as an air flaw or a finish flaw is unavoidable in manufacturing, so that it is stable. The inspection of the lip scratch is essential to maintain the sealing performance. In the lip inspection, there is a change from a visual inspection that simply checks the appearance or a human inspection judgment that relies on a finger touch to a highly accurate inspection method based on a light leak inspection that uses an optical device. In the light leakage inspection consisting of this optical device, a dark place is formed by a light-shielding case and a light-shielding jig that has a tightening margin for the lip part for the object such as a rotating seal, and a light beam is applied from below to form a gap. It is a general inspection method to cause light leakage in a scratched portion where a defect occurs, recognize this with a camera, and judge the quality of a defective scratch or the like based on the degree of the leakage. (Not shown)

[0003]

However, in the above-described light leakage inspection method in which the light beam is simply applied to the subject, not only small scratches but also serious defects such as waviness / distortion or eccentricity are accurately identified. In addition, it has a drawback that it cannot be determined as defective. In other words, defective cutting scratches or molding scratches are those that are minute, or have the property of retaining the original shape by being restored due to an elastic body.To inspect this, enhance the sensing accuracy of the camera, Alternatively, it is necessary to take measures such as increasing the number of installations, and this is still not a sufficient countermeasure against the above-mentioned tear scratches that are hidden by restoration.

In addition, when the rotary seal is fitted into the jig, the lip of the rotary seal may be turned over, and even if the lip is mounted, the amount of deformation of the lip portion due to misalignment between the jig and the rotary seal or variation in the seal diameter. Is not stable and it is difficult to detect scratches. Therefore, we must say that the credit accuracy of the inspection is low. An object of the present invention is to eliminate the above-mentioned drawbacks and to develop an inspection method capable of accurately inspecting a mechanical defect of a lip made of an elastic body and enabling automatic inspection.

[0005]

According to the present invention, there is provided a rotary seal (1a) having a lip (1a) which is mounted on a rotary portion and is made of an elastic material such as synthetic rubber or synthetic resin for sealing fluid of the rotary portion. 1) The inspection apparatus described in 1) holds a rotary seal (1) and rotates every 1 / n (inspection range is divided into n) rotations as shown in FIG. Grip (2) and central angle (360 / n +
With a sector shape of α) ° (α> 0), the radius of curvature of the arc portion (3a) can be pressed against the lip (1a) of the rotary seal (1) .
A fan-shaped jig (3) that has a tightening margin that is 0 to 10% larger than the diameter on the radial side and presses and moves toward the lip (1a), and to the inside of the grip portion (2) as shown in FIG. It is characterized by comprising a light source (4) arranged and an imaging device (5) arranged outside the gripping part (2) as shown in FIG.

A method of inspecting a rotary seal (1) having a lip (1a) formed of an elastic body such as synthetic rubber or synthetic resin for sealing a fluid, wherein the inspecting apparatus is the same as that of FIG. As shown in FIG. 2, the rotary seal (1) is gripped and the gripper (2) that rotates every 1 / n (dividing the inspection range into n) and the central angle (360 / n + α) ° (α>
(0) is a sector shape and the radius of curvature of the arc portion (3a) is 0-10% larger than the diameter on the inner diameter side that can be pressed against the lip (1a) of the rotary seal (1) and is pressed against the lip (1a). It is composed of a fan jig (3) to be attached, a light source (4) arranged inside the gripping part (2), and an image pickup device (5) arranged outside the gripping part (2). , The grip (2)
After gripping and fixing the rotary seal (1) with, the fan-shaped jig (3) is moved and pressed against the lip (1a) of the rotary seal (1), and the lip is inserted from the inside of the grip (2). Light is emitted from the light source (4) toward (1a) to promote light leakage, and image processing is performed by the image pickup device (5) arranged outside the grip portion (2) to determine light leakage. It has a feature.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION According to the present invention, in the inspection for determining the quality of the lip (1a) as described above, the gripping portion (2) is used.
As shown in FIG. 2, the lip (1a) is irradiated with the light source (4) from the inside of the fan-shaped jig (3) having a larger tightening margin than the conventional light-shielding jig. 1)
The fan jig (3) by moving it toward the lip (1a) of
The imaging device in which the circular arc portion (3a) is pressed toward the inner diameter side of the lip (1a) to spread and amplify the problematic shape such as a scratch or a distorted portion, and the determination of the pass / fail thereof is installed outside. It proposes an inspection device and an inspection method according to (5).

In the inspection device, the rotary seal (1) has a gripping portion (2) that rotates by gripping the rotary seal (1) and an arc portion (3a) larger than the lip diameter to contact the lip (1a) of the rotary seal (1). It comprises a fan-shaped jig (3), a light source (4) for illuminating the contact portion, and an image pickup device (5) for photographing the contact portion. On the other hand, in the inspection method, after the rotary seal (1) is gripped and fixed by the gripping part (2), the fan jig (3) is pressed to the inner diameter side of the lip (1a) of the rotary seal (1), and the inner side thereof is pressed. Light is radiated from the above to the lip (1a) to promote light leakage, and the light leakage is taken in by the image pickup device (5) arranged outside the gripping part (2), and this is taken in by the image processing device. Processing is performed to determine pass / fail.

[0009]

EXAMPLES The present invention will be described in detail with reference to Examples. First, as shown in FIGS. 1 and 2, first, mount the rotary seal (1) to be inspected on the gripping part (2). , This is fixed by the seal gripping part (2), and then toward the lip (1a) of the rotary seal (1), a circular arc part (3) with a central angle (360 / n + α) ° (α> 0) is formed.
The radius of curvature of a) has a tightening margin of 0 to 10% larger than the diameter of the lip (1a) of the rotary seal (1), and the fan-shaped jig (3) that presses against the lip (1a) is moved and pressed closely. . At this time, the tightening margin of the lip (1a) with respect to the fan-shaped jig (3) is 0 to 1 according to the shape of the fan.
It is preferable to press the arc with a large arc of about 0%, which is larger than that of the conventional shading jig.

The lip (1a) which is in close contact with the fan-shaped jig (3) has a fan-shaped arc portion (3a) having the central angle (360 / n + α) ° (α> 0) as described above. Since the radius of curvature is 0 to 10% larger than the diameter of the lip (1a) of the rotary seal (1), the contact portions at both ends of the fan-shaped jig (3) have a function of pulling and expanding the flaw from the left and right during pressing, and thus the minute contact Even a molding flaw will be highlighted. In this state, if light is radiated from the inside of the rotary seal (1) toward the lip (1a) of the rotary seal (1), a considerable amount of light leakage will occur at the defective portion, and the defective shape can be clearly confirmed. Therefore, it is extremely easy to visually recognize the image pickup device (5) arranged outside.

In the shape of the rotary seal (12),
1 and 2 show a single type lip (1a) having a single contacting lip, the present invention is not limited to this. For example, although not shown, a double lip type having a plurality of lips can be adopted. is there. When the range is inspected and determined in this way, the gripping part (2) for gripping the rotary seal (1) rotates 1 / n from there to test the other divided part, and this step is continued to complete the entire circumference. Complete the inspection.

[0012]

With the above-described structure, the following excellent effects can be obtained. In the present invention, a fan-shaped jig (3) having an interference larger than the diameter of the lip (1a) is attached to the lip (1
a) by making partial contact with the lip (1
The defect of a) such as scratches, cracks, and deformation is pulled and expanded from the left and right, and the light leaking from the defect is accurately recognized to enable accurate pass / fail judgment based on the degree of scratches. Therefore, it is possible to perform an accurate inspection with a simple imaging device, and it is possible to perform an automatic inspection with the inspection device.

[Brief description of drawings]

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

FIG. 2 is a plan view of FIG.

[Explanation of symbols]

1 rotating seal 1a lip 2 grip 3 fan jig 3a arc part 4 light sources 5 Imaging device

Claims (2)

(57) [Claims] 1. An inspection device for a rotary seal having a lip formed of an elastic body such as synthetic rubber or synthetic resin for sealing a fluid, wherein the inspection device grips the rotary seal for 1 / n (inspection range). (Divided by n) and a gripper that rotates every rotation, and a radius of curvature of the circular arc portion with a central angle (360 / n + α) ° (α> 0) of 0 to 10 from the diameter of the lip on the inner diameter side that can be pressed against the rotary seal . % A fan-shaped jig that has a large interference and moves toward the lip and presses it, a light source arranged inside the grip portion, and an imaging device arranged outside the grip portion. A rotating seal inspection device characterized by being performed. 2. A method for inspecting a rotary seal having a lip formed of an elastic body such as synthetic rubber or synthetic resin for sealing a fluid, wherein the inspection device grips the rotary seal and 1 / n (inspection range). (Divided into n) and a gripper that rotates with each rotation, and a radius of curvature of the arc-shaped part with a central angle (360 / n + α) ° (α> 0) of 0 to 10 from the diameter on the inner diameter side that can be pressed against the lip of the rotary seal. % A fan-shaped jig having a large tightening margin to press against the lip, a light source arranged inside the grip portion, and an image pickup device arranged outside the grip portion, After the rotary seal is gripped and fixed at the section, the fan-shaped jig is moved and pressed against the lip of the rotary seal, and light is emitted from the light source from the inside of the grip section toward the lip to leak light from the scratched section. The outside of the grip. Inspection method of a rotating seal characterized in that the determination of light leakage by the arrangement an imaging device.