JP3357317B2 - Surface inspection equipment for spherical objects - 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 the surface of a spherical object such as a ball for a ball bearing for scratches or chips.

[0002]

2. Description of the Related Art Conventionally, for example, the presence or absence of cracks in the surface of a ball for a ball bearing having a spherical shape, or the seam line of a ball having a loop-shaped single line having a dumbbell-shaped seam line on the surface. For example, an image processing apparatus equipped with a solid-state CCD camera or the like has been used. However, the handling is more complicated than the spherical shape, which is a feature of the shape, and it is difficult to perform high-speed and high-precision automatic inspection. For example, Japanese Unexamined Patent Publication
Japanese Patent No. 34326 discloses a seam inspection method and a seam inspection method capable of improving the seam line inspection accuracy. The first axis X and the second axis X support a ball to be inspected and cross the ball at right angles. There is disclosed an apparatus for inspecting the surface of a spherical object by an apparatus having a rotation driving means for alternately rotating around an axis Y.

[0003]

However, Japanese Patent Laid-Open No. 6-3 / 1994
In the apparatus disclosed in Japanese Patent No. 4326, in order to inspect the entire circumference of a spherical object as an inspection object, at least four rotation driving means for rotating the spherical object around different rotation axes are opposed by two. It is necessary to arrange it. In the device disclosed in this publication, it is necessary to carry the ball into the holding device, set it on the rotary drive means, and carry it out after the inspection, so that the throughput of the inspection is reduced. In addition, the apparatus becomes large in size for rotating the spherical object to be inspected, for handling of loading and unloading, and the like, and the price becomes expensive.

The present invention has been made to solve the above-mentioned problems, and to provide an inexpensive and small-sized apparatus for continuously and rapidly inspecting the outer peripheral surface of an article to be inspected having a spherical shape.

[0005]

According to a first aspect of the present invention, there is provided an apparatus for inspecting defects on the entire surface of a spherical object, comprising: a rotating mechanism for rotating the spherical object; An inspection apparatus comprising: an illumination mechanism that emits illumination light; a detection mechanism that detects light reflected from the spherical object; and a determination mechanism that determines a defect based on an input signal from the detection mechanism, The mechanism consists of two rotating rollers facing each other, the gap between the two rotating rollers is smaller than the diameter of the sphere, and the two rotating rollers rotate in the same direction to each other, and one of the two rotating rollers the guide groove of the sphere was provided on the surface of the induction groove you have the shape of a helical thread
The intermittent operation of the rotation of the rotating roller
An inspection apparatus according to claim Rukoto. The invention according to claim 2 is the inspection apparatus according to claim 1, wherein when the diameter of the spherical object is 2r, the pitch P of the spiral screw of the guide groove is 2r or more. The invention according to claim 3 is an apparatus for inspecting defects on the entire surface of a spherical object.
A rotating mechanism for rotating the sphere, and the sphere
An illumination mechanism for irradiating the object with illumination light;
A detection mechanism for detecting the emitted light; and an input signal from the detection mechanism.
Inspection equipment consisting of a discrimination mechanism for discriminating defects based on
And two rotating rollers facing the rotating mechanism.
And the gap between the two rotating rollers is the diameter of the spherical object.
The two rotating rollers are in the same direction as each other
To a sphere on one surface of the two rotating rollers
A guiding groove for an object is provided, and the guiding groove includes a groove 1 having a shape of a spiral screw and a groove 2 having a guiding groove having a shape perpendicular to the rotation axis. The groove 1 and the groove 2 are continuously formed. In the case where the diameter of the spherical object is set to 2r, the guiding groove is provided.
An inspection apparatus characterized in that the length L2 of the part 2 is 2πr or more . Further, in the invention according to claim 4, when the diameter of the spherical object is 2r, the pitch P of the spiral screw of the guide groove is
Claim, characterized in that 2 is is (2/3) r or 3
It is an inspection device of the description. The invention according to claim 5 is the inspection device according to claims 3 or 4, wherein the rotation of the rotary roller having the guide groove is continuously operated.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. In the drawings, the same reference numerals indicate the same or corresponding parts. The embodiments disclosed this time are to be considered in all respects as illustrative and not restrictive.

FIG. 1 is an overall configuration diagram of an inspection apparatus (1) according to the present invention, which is a view showing a direction parallel to a transport direction of an article to be inspected (2). In FIG. 1, the article to be inspected (2) is transported in the direction indicated by the arrow X. FIG. 2 is a perspective view of a part of the inspection apparatus. In FIG. 2, the article to be inspected (2) is transported in the direction indicated by the arrow Y.

As can be seen from FIGS. 1 and 2, the inspection apparatus (1) of the present invention is a spherical object (2) which is an article to be inspected.
A rotation mechanism (10) for rotating the sphere, an illumination mechanism (30) for irradiating the sphere (2) with illumination light, a detection mechanism (40) for detecting reflected light from the sphere (2), A determination mechanism (50) for determining a defect based on an input signal from the detection mechanism (40). A supply hopper (3) for sequentially feeding the spheres (2) to the inspection device (1) is provided upstream of the inspection device (1), and an inspection device (3) is provided downstream of the inspection device (1). Defective hopper (4) that receives the ball (2) determined to be defective in 1)
And a spherical object (2) determined to be good by the inspection device (1)
A conveyor (5) is provided to convey this to the next step. Then, the rotating mechanism (10) moves in the same direction (FIG. 2).
Roller (1) that rotates in the Z direction indicated by the arrow in FIG.
1) and (12) are arranged facing each other in the horizontal direction, and the spherical object (2) can be placed in the gap.

The rotating mechanism (10) is provided on a surface of one of the pair of rotating rollers (11), (12), and one of the rotating rollers, which are disposed to face each other in the horizontal direction. It comprises a guiding groove (16) and an adhesive member (13) provided on the other rotating roller (12).
In addition, each of the rotating rollers (11) and (12) rotates in the direction indicated by the arrow Z about the rotating shafts (14) and (15), respectively, and the two rotating rollers do not interfere with each other. Rotation ON / OFF control and rotation speed control can be performed.

In addition, two rotating rollers (11), (1)
In the gap 2), the distance d between the surfaces is smaller than the diameter 2r of the spherical object (2).

The adhesive member (13) is, for example, a spherical object (2)
The material is not particularly limited as long as the material has high friction. When the spherical material (2) is made of steel, a sheet material such as rubber may be wound around the surface of the rotating roller (12).

Although the shape of the guide groove (16) will be described later, in the first invention of the present invention, the guide groove (1) is formed.
6) has a helical shape over the entire circumference, and in the second invention, has a shape having both a helical screw portion and a portion perpendicular to the rotation axis of the rotating roller.

The lighting mechanism (30) is, as shown in FIG.
A plurality of optical fibers are about the length of the rotating rollers (11) and (12), are arranged side by side with the rotating rollers, and collect the lens (3) for irradiating the surface of the spherical object (2).
1) and a lighting device (3
4), the condenser lens section (31) and the illumination device (3).
4) and an optical fiber bundle (33). Note that the condenser lens section (31) and the optical fiber bundle (3
3) is connected via a connector (32).

The detecting mechanism (40) has a C function as shown in FIG.
A sensor (41) in which CD elements are arranged, for example, a CCD line sensor in which CCD elements are arranged one-dimensionally or a CCD image sensor in which two-dimensional CCD elements are arranged two-dimensionally, and an objective lens (42) Is what is done.
The arrangement of the CCD elements is characterized in that a high resolution can be obtained with a small number of elements if it is one-dimensional, and that the visual field is not linear but flat when it is two-dimensional. It should be noted that even in the case of a one-dimensional CCD line sensor, 2
Even in the case of a dimensional CCD image sensor, if the spherical object (2) is fixed and sensing is performed from one direction, the entire surface of the spherical object (2) cannot be inspected. Further, the viewing angle of the sensor depends on the resolution of the sensor and the distance between the spherical object (2) and the sensor, but about one third of the surface of the spherical object (2) falls within the viewing angle.

The discriminating mechanism (50) is a known image processing device, and based on an input signal from the detecting mechanism (40) if the detecting mechanism (40) is constituted by a one-dimensional CCD line sensor. For example, when the change of the time differential value of the input signal exceeds a certain value, a defect such as a scratch on the surface of the spherical object (2) is detected. The detection mechanism (40) is a two-dimensional CC
If it is composed of a D imaging sensor, the detection mechanism (4
Based on the input image from 0), for example, a defect such as a scratch on the surface of the spherical object (2) is detected when the luminance value after the input image is subjected to the black and white binarization processing exceeds a certain value.

Next, the rotation mechanism (10) will be described in detail.

First, the rotation mechanism according to the first aspect of the present invention will be described. FIG. 3 is a side view and FIG. 4 is a perspective view thereof. As described above, the two rotating rollers (11) and (12) are disposed to face each other in the horizontal direction, and the gap d is configured to be smaller than the diameter 2r of the spherical object (2). Further, the guide groove (16) provided on the surface of the rotating roller (11) has a continuous shape of a spiral screw having a pitch P1 as shown in FIG. The pitch P1 is preferably equal to or larger than 2r, which is the diameter of the spherical object (2). By doing so, the spherical object (2) makes one rotation in the direction of arrow B while the rotating roller (2) makes one rotation.

Next, the rotation mechanism according to the second aspect of the present invention will be described. FIG. 5 is a side view, FIG. 6 is a perspective view, and FIG. 7 is a sectional view. As described above, the two rotating rollers (21) and (22) are horizontally opposed to each other, and the gap d is configured to be smaller than the diameter 2r of the spherical object (2). A guide groove (26) provided on the surface of the rotating roller (21).
Has a groove 1 (26a) having a shape of a spiral screw having a pitch P2 and a groove 2 (26b) having a shape perpendicular to the rotation axis, as shown in FIG. This pitch P2 is 1/1 / 2r which is the diameter of the spherical object (2).
It is preferably three or more. By doing so, the spherical object (2) makes one rotation in the direction of arrow B while the rotating roller (21) makes at least three rotations. When the length L2 of the groove 2 (26b) is 2r in diameter of the spherical object (2), it is preferable that L2 is 2πr or more. By doing so, the spherical object makes one rotation in the direction of arrow A from the start point to the end point of the groove 2 (L2).

Next, the operation of inspecting the entire outer peripheral surface of the spherical object (2) using the inspection apparatus (1) of the present invention will be described.

First, as shown in FIG.
Is supplied to the supply hopper (3), and drops at regular intervals from a supply port provided below the supply hopper (3) into a gap between two rotating rollers of the rotating mechanism (10). After that, the spherical object (2) is conveyed in the arrow Y direction by the rotation of the rotating roller in the arrow Z direction.

In the inspection apparatus according to the first aspect of the present invention, a spiral screw-shaped guide groove (16) is provided over the entire circumference of the rotary roller (11), and a spherical shape is formed along the screw-shaped guide groove. The object (2) is rotated in the direction of arrow B in FIG. In the first invention, after the spherical object (2) falls into the gap between the rotating roller (11) and the rotating roller (12), the operation is performed as follows.

First, two rotating rollers (11), (1)
In 2), only the rotating roller (12) without the guide groove is rotated, and the other rotating roller (11) with the guide groove is rotated.
Do not rotate. In this state, the rotating roller (12) rotates the spherical object one or more times in the direction of arrow A in FIG.
To rotate. Since the adhesive member (13) is provided on the surface of the rotating roller (12), the spherical member (2) does not slip due to friction between the adhesive member (13) and the spherical member (2). ) Causes the spherical object to rotate by one rotation.

During the rotation of the rotating roller (12), the spherical object (2) is condensed by the condenser lens (31) of the illumination mechanism (30).
And the reflected light is detected by the detection mechanism (41). From the detection mechanism (40) to the discrimination mechanism (50)
The signal is transferred to the controller, and the determination mechanism (50) determines whether or not the surface is damaged. This means that the surface inspection for one round in the direction of arrow A within the viewing angle of the detection mechanism (40) (approximately 1/3 of the spherical object) has been completed.

Next, both the rotating roller (11) and the rotating roller (12) are moved in the same direction (arrow Z in FIG. 2).
Direction). Thereby, the spherical object (2) is guided by the guide groove (16) and rotates in the direction of arrow B. The amount of rotation depends on the viewing angle of the detection mechanism (40),
In the detection mechanism using the CD element, one third of the spherical object (2)
Since the surface of the degree is often within the visual field, the rotation amount is 1
It may be about / 3 rotation.

Since the pitch P1 of the guide groove (16) is equal to or larger than the diameter 2r of the spherical object, the inspection of the entire circumference of the spherical object (2) is completed when the rotating roller (11) makes at least one rotation. . That is, the rotating roller (11)
The state where the roller is rotated by / 3 is a state where the roller is rotated by 1/3 in the direction of arrow B from the initial state, and the rotation of the rotating roller (11) is stopped in this state. One rotating roller (1
In 2), the rotation is continued as it is, and in this state, the rotating roller (12) is rotated so that the spherical object makes one or more rotations in the direction of arrow A in FIG. While the rotating roller (12) is rotating, the determination mechanism (50) determines whether or not there is a scratch on the surface. As a result, the surface inspection for one round in the direction of arrow A within the next viewing angle of the detection mechanism (40) is completed.

Next, as before, the rotating roller (1)
1) 1/3 turn to stop. In this state, the rotating roller (12) is rotated, and the rotating roller (12) is rotated.
During the rotation of, the determination mechanism (50) determines whether or not there is a scratch on the surface. This means that the surface inspection of the detection mechanism (40) for one turn in the direction of arrow A within the next viewing angle has been completed.

By doing so, the spherical object (2)
Has been completed.

Next, the operation of the inspection apparatus according to the second aspect of the present invention will be described. In the inspection apparatus according to the second aspect of the present invention, the rotary roller (21) has a spiral screw-shaped groove 1 (26a). And a groove 2 (26b) having a shape perpendicular to the rotation axis, and a spherical object (2) is formed along a groove 1 (26a) which is a screw-shaped guide groove in the direction of arrow B in FIG. 4 and a spherical object (2) is formed along the vertical groove 2 (26b) in FIG.
In the direction indicated by the arrow A in FIG.

In the second invention, after the spherical object (2) falls into the gap between the rotating roller (21) and the rotating roller (22), the operation is performed as follows. First, both the two rotating rollers (21) and (22) are rotated in the direction indicated by the arrow Z in FIG.

During the rotation of the two rotating rollers (21) and (22), the surface of the spherical object (2) is irradiated by the condenser lens (31) of the illumination mechanism (30), and the reflected light is detected. It is detected by the mechanism (41). A signal is transferred from the detection mechanism (40) to the discrimination mechanism (50), and the discrimination mechanism (50) discriminates the presence or absence of a surface flaw or the like.

In this case, the length L2 of the groove 2 (26b)
Is larger than the outer circumference 2πr of the spherical object (2), so that the surface inspection for one round in the direction of arrow A within the viewing angle of the detection mechanism (40) is completed. Also, the groove 1 (2) of the rotating roller (21)
By the rotation of 6a), the pitch P2 becomes the diameter 2r of the spherical object.
When the rotation roller (21) makes one rotation, the spherical object (2) is rotated at least 1/3 in the direction of arrow B.

The pitch P2 depends on the viewing angle of the detection mechanism (40). However, in a detection mechanism using a normal CCD element, about one third of the surface of the spherical object (2) is in the field of view. Therefore, the pitch P2 is 1/1 of the circumference of the detection object (2).
About 3 is sufficient. Then, when the rotation roller (21) rotates three times, the inspection of the entire circumference is completed. That is, the state in which the rotating roller (21) has made one rotation means a state in which the rotating roller (21) has been rotated by 1/3 in the direction of arrow B from the initial state. In this state, the rotation of the rotating roller (21) is not stopped.
(26b), it makes one or more rotations in the direction of arrow A, and the rotation is further continued.
In this state, since the rotation of the rotating roller (21) is not stopped even in this state, the groove portion 2 (2
6b), it makes one or more rotations in the direction of arrow A, the rotation continues, and the rotating roller (2)
The state in which 1) is rotated three times is a state in which it is rotated by 3/3 in the direction of arrow B from the initial state, and the inspection of the entire circumference is completed.

Those which have been determined as defective by the inspection of the outer peripheral surface of the spherical object (2) by the determining mechanism (50) are discharged to the defective product hopper (4). The defective product hopper (4) is composed of, for example, an air nozzle and a chute. When the defective product comes to the chute position, the defective air is discharged from the air nozzle to guide the defective product to the chute. On the other hand, the air nozzle does not operate for the inspection object (2) whose inspection result is normal, and the process proceeds to the next process on the transport conveyor (5).

[0034]

According to the inspection apparatus of the present invention, even when the article to be inspected is a spherical object, the entire circumference of the surface can be inspected at a high speed by rotating the spherical object by the rotating mechanism.

Further, according to the inspection apparatus of the present invention, in addition to the above-mentioned effects, the entire circumference of the surface can be inspected at high speed and continuously by rotating the rotating mechanism continuously to rotate the spherical object.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an inspection apparatus according to the present invention.

FIG. 2 is a perspective view of an inspection device according to the present invention.

FIG. 3 is a side view of the rotation mechanism of the first invention.

FIG. 4 is a perspective view of the rotation mechanism of the first invention.

FIG. 5 is a side view of the rotation mechanism of the second invention.

FIG. 6 is a perspective view of a rotation mechanism according to the second invention.

FIG. 7 is a sectional view of a rotation mechanism according to a second invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Inspection apparatus 2 Spherical object 10 Rotation mechanism of the first invention 20 Rotation mechanism of the second invention 30 Illumination mechanism 40 Detection mechanism 50 Discrimination mechanism

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G01N 21/84-21/958

Claims (5)

(57) [Claims] 1. An apparatus for inspecting defects on the entire surface of a spherical object, a rotation mechanism for rotating the spherical object, an illumination mechanism for irradiating the spherical object with illumination light, and a reflection from the spherical object. An inspection apparatus comprising: a detection mechanism that detects light; and a determination mechanism that determines a defect based on an input signal from the detection mechanism, wherein the rotation mechanism includes two opposed rotating rollers. The gap between the rotating rollers is smaller than the diameter of the sphere, the two rotating rollers rotate in the same direction, and a guiding groove for the sphere is provided on one surface of the two rotating rollers , and the guiding groove is spiral. The rotation of the rotating roller , which has a screw shape and has a guide groove, can be intermittently operated.
Inspection apparatus according to claim and. 2. The inspection apparatus according to claim 1, wherein when the diameter of the spherical object is 2r, the pitch P of the spiral screw of the guide groove is 2r or more. 3. An apparatus for inspecting defects on the entire surface of a spherical object.
There is a rotation mechanism for rotating the spherical object, an illumination mechanism for irradiating the spherical object with illumination light, a detection mechanism for detecting light reflected from the spherical object, and based on an input signal from the detection mechanism. Determine defects
An inspection device comprising a discriminating mechanism, wherein the rotating mechanism comprises two rotating rollers facing each other, and a gap between the two rotating rollers is smaller than a diameter of a spherical object.
In addition, the two rotating rollers rotate in the same direction as each other , and a guide groove of a sphere is provided on one surface of the two rotating rollers.
The guide groove comprises a groove 1 having a shape of a spiral screw, and a groove 2 having a shape perpendicular to the rotation axis. The groove 1 and the groove 2 are continuously connected and provided. A length L2 of the groove portion 2 of the guide groove is 2πr or more, where the diameter of the spherical object is 2r . 4. The inspection apparatus according to claim 3 , wherein when the diameter of the spherical object is 2r, the pitch P2 of the helical screw of the guide groove is (2/3) r or more. 5. The inspection apparatus of claims 3 to 4 wherein the rotation of the rotary roller having a guide groove that is continuous operation.