Method for inspecting appearance

Abstract

To provide a method for inspecting an appearance capable of semi-automatically performing appearance inspection of products, semi-finished products, and work-in-process items at a high level.SOLUTION: Product appearance inspection is performed in parallel by a first imaging line A and a second imaging line B. A product is imaged from one side in the first imaging line A, while a product is imaged from the other side in the second imaging line B. The captured images are stored in storage means, the appearance of the product is determined on the basis of the images stored in the storage means, and the product is sorted into one of acceptable products and unacceptable products. Determination of acceptable products and unacceptable products is performed by AI.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for inspecting the appearance of elements that constitute a motor, such as a stator core. [Background technology]

[0002] In recent years, automation of the inspection process has become widespread when visually inspecting the components of products, but visual inspection continues to be carried out in some fields (see Non-Patent Document 1 below). [Prior art documents] [Non-patent literature]

[0003] [Non-Patent Document 1] Manufacturing Process: Until the Product is Made (10) Visual Inspection Internet [Searched on May 9, 2024]<https: / / www.miyaki-denki.com / manufacturing-process / >

[0004] As shown in the above-mentioned Non-Patent Document 1, in the manufacturing process of a motor, the appearance of the motor is visually inspected to check for abnormalities such as scratches or dirt on the appearance, and for problems with the molding dimensions. Non-Patent Document 1 shows a visual inspection process for a stator with a winding wound thereon via an insulator, but this type of inspection can be performed in any process, such as on the stator core alone. Summary of the Invention [Problem to be solved by the invention]

[0005] As such, when visually inspecting the appearance of work-in-progress products during the manufacturing process, it is naturally difficult to standardize the quality of the inspection because it depends on the ability of the inspector. Furthermore, even for experienced inspectors, visual inspection takes a certain amount of time, and the number of inspectors required to inspect a large number of products must increase.

[0006] Therefore, an object of the present invention is to disclose a visual inspection method that can shorten inspection time, reduce the number of inspectors required, and standardize inspection quality by automatically performing visual inspections of finished products, semi-finished products, and work-in-progress products such as motor stator cores. [Means for solving the problem]

[0007] The invention described in claim 1 is a visual inspection method characterized by setting an object to be inspected on a first imaging stand, moving the first imaging stand to a first imaging room, photographing the object to be inspected from one side in the first imaging room, inverting the object to be inspected upside down after imaging in the first imaging room is completed and setting it on a second imaging stand, moving the second imaging stand to a second imaging room, photographing the object to be inspected from the other side in the second imaging room, and using the images photographed from the one side and the other side, checking for the presence or absence of scratches or dirt on the appearance of the object to be inspected.

[0008] The invention described in claim 2 is a visual inspection method described in claim 1, characterized in that images taken from one side and another side of the object to be visually inspected are saved, and the presence or absence of scratches or dirt on the appearance of the object to be visually inspected is confirmed from the saved images using artificial intelligence.

[0009] The invention described in claim 3 is a visual inspection method described in claim 1 or claim 2, characterized in that the object to be visually inspected is clamped by a robot arm and moved upside down from the first shooting stage on the first shooting line to the second shooting stage on the second shooting line.

[0010] The invention described in claim 4 is a visual inspection method described in claim 1 or claim 2, characterized in that after checking for the presence or absence of external scratches or dirt, if the product is determined to be a passing product, the object to be visually inspected is moved to a passing conveyor by a robot arm, and if the object to be visually inspected is determined to be a failing product, it is moved to a failing conveyor by a robot arm.

[0011] The invention of claim 5 is the appearance inspection method of claim 1 or claim 2, characterized in that the first imaging table is moved between the start position and the initial position via the first imaging chamber by a conveyor or a slider.

[0012] The invention of claim 6 is the appearance inspection method of claim 1 or 2, characterized in that the second imaging table is reciprocated between an initial position and the second imaging chamber by a conveyor or a slider. [Effects of the Invention]

[0013] According to the invention of claim 1, the visual inspection of products can be semi-automated, which reduces the number of inspectors and shortens the inspection time.

[0014] According to the invention of claim 2, the appearance inspection of the product is confirmed by artificial intelligence, so that the quality of the inspection can be made uniform at a high level.

[0015] According to the invention described in claim 3, it is possible to automate the movement of the object to be inspected from the first imaging table on the first imaging line to the second imaging table on the second imaging line, and it is also possible to easily and reliably invert the vertical position of the object to be inspected during the movement.

[0016] According to the invention described in claim 4, after the visual inspection is completed, the visual inspection object can be automatically sorted into a pass conveyor or a fail conveyor, and the sorted visual inspection object can be transported to the outside by one of these conveyors.

[0017] According to the invention of claim 5, the photographing of the object to be visually inspected in the first photographing room can be carried out efficiently and continuously.

[0018] According to the invention of claim 6, the photographing of the object to be visually inspected in the second photographing room can be carried out efficiently and continuously. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a configuration diagram of a visual inspection device according to the present invention; [Figure 2] 10 is a flowchart illustrating a method for inspecting the appearance of an Nth object to be inspected. [Figure 3] 10 is a flowchart illustrating a method for inspecting the appearance of an (N+1)th object to be inspected. DETAILED DESCRIPTION OF THE INVENTION

[0020] An embodiment of the present invention will be described below with reference to Figures 1 to 3. As shown in Figure 1, the appearance inspection device of the present invention is generally composed of a first photographing line A, a second photographing line B, a pass conveyor C, and a fail conveyor D.

[0021] The first photographing line A is equipped with a first photographing table 1 on which the product to be inspected visually (which may be a semi-finished product or a work in progress; in this embodiment, a stator core, which is a component of a motor, is used as an example) is set, and a first photographing room 2 in which the stator core set on the first photographing table 1 is photographed.

[0022] The first imaging room 2 has openable and closable doors (shutters) at the entrance and exit. Multiple cameras are installed in the first imaging room 2 to photograph the exterior of the stator core, and the photographed images are stored in a storage device such as a hard disk (HD) of a PC (personal computer) (not shown).

[0023] In addition, the first photographing line A has a position (starting position) where the stator core is set on the first photographing table 1 and a position (initial position) to which the stator core is moved after its appearance has been photographed in the first photographing room 2.

[0024] The stator core set on the first radiography table 1 is moved from the starting position to the first radiography chamber 2, and from the first radiography chamber 2 to the initial position by a conveyor or slider. If a conveyor is used, the movement is automatic, and if a slider is used, it can be moved with little manual effort.

[0025] The second photography line B is equipped with a second photography stand 3 on which the stator core is set after being photographed on the first photography line A, and a second photography room 4 in which the stator core set on the second photography stand 3 is photographed. The second photography room 4 is equipped with openable and closable doors (shutters) at the entrance and exit. Multiple cameras are installed inside the second photography room 4 to photograph the exterior of the stator core, and the photographed images are stored in a storage device such as a hard disk (HD) of a PC (personal computer).

[0026] The second imaging line B is provided with a position (initial position) where the stator core is set on the second imaging table 3. The stator core set on the second imaging table 3 is moved between the initial position and the second imaging chamber 4 by a conveyor or slider. In the case of a conveyor, the movement is automatic, while in the case of a slider, the movement is made possible by manual effort with little force.

[0027] The images taken by the first imaging line A and the second imaging line B and stored in the aforementioned storage means are checked by AI for the presence or absence of scratches or dirt, and the products are distinguished as pass or fail. For example, by taking images of multiple stator core samples in advance and having the AI ​​learn about the presence and absence of scratches or dirt, it is possible to set criteria for distinguishing pass or fail products.

[0028] The pass conveyor C and the reject conveyor D are conveyors on which the passed and rejected stator cores that have undergone visual inspection are placed and automatically carried away.

[0029] Next, the operation of the above-mentioned appearance inspection device will be described. First, an inspector turns on the power of the appearance inspection device shown in Fig. 1, and activates the first photographing line A and the second photographing line B (step S1 in Fig. 2).

[0030] Next, the first imaging stage 1 is moved to the start position of the first imaging line A (step S2). Then, the first (Nth) stator core is set on the first imaging stage 1 (step S3).

[0031] In this state, when the start button 5 (see Figure 1) for the first imaging line A is pressed (step S4), the stator core on the first imaging table 1 moves into the first imaging room 2 (step S5), and the entrance door to the first imaging room 2, which is in the open state, is closed (step S6).

[0032] Once the entrance door is closed, a camera in the first imaging room 2 captures an image of the exterior of the first (Nth) stator core from the top to the side (hereinafter referred to as one side) (step S7), and the captured image is saved in storage means (a PC's hard disk) as information about one side of the first (Nth) stator core. Once imaging is complete, the exit door of the first imaging room 2 is opened (step S8), and the first (Nth) stator core is moved to its initial position on the first imaging line A (step S9).

[0033] The first (Nth) stator core that has been moved to its initial position is clamped by a robot arm or the like, turned upside down, and then moved to its initial position on the second photographing line B (step S10). At the same time, the first photographing stand 1 on the first photographing line A moves to its start position (S11). This completes the initial flow. The first (Nth) stator core waits in the state of steps S10 and S11.

[0034] Next, the flow from the second time onwards will be described. In the second flow, the second (N+1)th stator core is set on the first imaging stage 1 located at the start position of the first imaging line A (step S21 in FIG. 3).

[0035] In this state, when the start button 5 (see FIG. 1) for the first imaging line A is pressed (step S22), the second (N+1) stator core moves into the first imaging chamber 2 for the first imaging line A (step S23).

[0036] When the second (N+1) stator core enters the first imaging chamber 2 of the first imaging line A, the entrance door of the first imaging chamber 2 is closed (step S24). At the same time, the first (N) stator core, which has been set on the second imaging table 3 of the second imaging line B and is waiting in its initial position, moves into the second imaging chamber 4 (step S25), and the entrance door of the second imaging chamber 4, which is in an open state, is closed (step S26).

[0037] In the first imaging room 2, one side of the second (N+1) stator core is photographed (step S27), and in the second imaging room 4, the upper side (hereinafter referred to as the other side) of the first (N) stator core after it has been turned upside down is photographed, and the images are saved in storage means (PC hard disk) (step S28). Now that photography of one side (upper side) and the other side (lower side) of the first (N) stator core has been completed, the images are checked using AI from the image data saved in the storage means, and the appearance of the first (N) stator core is inspected for scratches or stains. If there are no scratches or stains, the product is judged to be acceptable, and if there are scratches or stains, the product is judged to be unacceptable (step S29).

[0038] The image after the determination is stored in a storage means such as an external HD as the appearance image data of the first (Nth) stator core (step S30). The image stored in the storage means such as an external HD on the PC may or may not be deleted.

[0039] Thereafter, the exit door of the first imaging room is opened (step S31), and the second (N+1) stator core is moved to the initial position of the first imaging line A (step S32). Also, the exit door of the second imaging room is opened (step S33), and the first (N) stator core is moved to the initial position of the second imaging line A (step S34).

[0040] The second (N+1) stator core that has been moved to the initial position on the first photographing line A is then turned upside down by a robot arm or the like, and moved to the initial position on the second photographing line B (step S35) and waits there. The first photographing stand 1 on the first photographing line A moves to the start position (step S36) and waits there.

[0041] The first (Nth) stator core that has been moved to the initial position of the second photographing line B is moved to a pass conveyor or a fail conveyor (step S37) by a robot arm or the like based on the judgment result by the AI ​​described above (step S29), and carried out. This completes the visual inspection of the first (Nth) stator core.

[0042] From then on, by going through step S37, one side (upper side) of the second, third, fourth, etc. stator core is photographed using the first photographing line A, and the other side (lower side) of the stator core is photographed using the second photographing line B, and the appearance inspection of the stator core is repeatedly performed by checking for scratches and dirt using AI based on the images from both sides.

[0043] As explained above, the visual inspection device of the present invention allows visual inspection of products (finished products, semi-finished products, work-in-progress products) to be carried out simultaneously in parallel using the first photographing line A and the second photographing line B. In addition, since the majority of the visual inspection of products can be automated, it is possible to reduce the number of inspectors required and shorten the inspection time. Furthermore, unlike visual inspection methods performed by inspectors, it is possible to achieve a high level of uniformity in the quality of the inspection without relying on the inspector's level of skill. [Industrial Applicability]

[0044] The present invention is applicable to the visual inspection of various products, semi-finished products, and work-in-progress products. [Explanation of symbols]

[0045] 1. First camera stand 2. First Photography Studio 3 Second camera stand 4. Second Photography Studio 5 Start button A 1st imaging line B 2nd imaging line C Pass conveyor D Reject conveyor

Claims

1. An appearance inspection method characterized by setting an object to be inspected on a first photographing table, moving the first photographing table to a first photographing room, photographing the object to be inspected from one side in the first photographing room, inverting the upside-down position of the object to be inspected on a second photographing table after photographing in the first photographing room is completed, and moving the second photographing table to the second photographing room, photographing the object to be inspected from the other side in the second photographing room, and using the photographed image from the one side and the photographed image from the other side, checking for the presence or absence of scratches or dirt on the appearance of the object to be inspected.

2. 2. The appearance inspection method according to claim 1, wherein an image taken from one side of the object to be inspected and an image taken from the other side are saved, and the presence or absence of scratches or stains on the appearance of the object to be inspected is confirmed from the saved images using artificial intelligence.

3. 3. The appearance inspection method according to claim 1, wherein the object to be inspected is clamped by a robot arm and moved upside down from a first imaging table on the first imaging line to a second imaging table on the second imaging line.

4. A visual inspection method as described in claim 1 or claim 2, characterized in that if the visual inspection object is judged to be a passing product after checking for the presence or absence of external scratches or dirt, the visual inspection object is moved to a passing conveyor by a robot arm, and if the visual inspection object is judged to be a failing product, the visual inspection object is moved to a failing conveyor by a robot arm.

5. 3. The appearance inspection method according to claim 1, wherein the first imaging table is moved between a start position and an initial position via the first imaging chamber by a conveyor or a slider.

6. 3. The appearance inspection method according to claim 1, wherein the second imaging table is reciprocated between an initial position and the second imaging chamber by a conveyor or a slider.

Images