A method for visual inspection of motors

Abstract

The present invention aims to provide a fully automatic appearance inspection method for a motor visual inspection method that greatly improves the appearance inspection effect and efficiency of the motor. It adopts four inspection stations for inspection. The motor is sequentially sent to the four inspection stations through a conveying mechanism to inspect small shell damage, terminal deformation, reverse installation of the coding magnet, poor terminal height, one of the motor's pressing claws not holding the small shell, motor missing pressing claws, missing coding magnets, poor coding magnet height, missing coding magnets, reverse labeling, missing or dirty QR code of the label, QR code and label edge size not within the specification range, repeated labeling, wrong labeling, crooked labeling, missing labeling, large shell with writing, screw hole damage, shaft damage, gear oxidation, large shell missing tapping, foreign matter in the screw hole, gear damage and other defect items. The present invention can be applied to the field of appearance inspection of products such as motors and inductors.

Description

Technical Field

[0001] The invention relates to a method for detecting the appearance of a motor, and in particular to a method for visually detecting a motor. Background Art

[0002] In the process of motor production, in order to ensure the quality of the product, it is necessary to conduct factory inspection on various indicators of the product, among which appearance inspection is a key indicator of product inspection. At present, most of the appearance inspections are carried out by manual inspection, which is greatly affected by human subjectivity, so it is difficult to ensure consistency. In addition, as customers have higher and higher requirements for product quality, it is necessary to conduct a comprehensive inspection of the appearance of the motor, such as small shell damage, terminal deformation, reverse installation of the coding magnet, poor terminal height, one of the motor's pressure claws not buckling the small shell, motor missing pressure claws, missing coding magnets, poor coding magnet height, missing coding magnets, reverse labeling, missing or dirty QR code of the label, QR code and label edge size not within the specification range, repeated labeling, wrong labeling, crooked labeling, missing labeling, large shell with writing, screw hole damage, shaft damage, gear oxidation, large shell missing tapping, foreign matter in the screw hole, gear damage and other defective items. If manual methods are used, it is difficult to meet production needs. Therefore, it is particularly important to provide an efficient, comprehensive and high-accuracy detection method. Summary of the invention

[0003] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a motor visual inspection method that can greatly improve the motor appearance inspection effect and efficiency.

[0004] The technical solution adopted by the present invention is: the present invention adopts four inspection stations, the motor is sequentially sent to the four inspection stations through the transmission mechanism, and the small shell damage, terminal deformation, reverse installation of the coding magnet, poor terminal height, one of the motor's pressing claws not buckling the small shell, the motor missing pressing claw, the coding magnet is missing, the coding magnet height is poor, the coding magnet is missing, the label is reversed, the label QR code is missing or dirty, the QR code and the label edge size are not within the specification range, repeated labeling, the label is wrongly placed, the label is crooked, the label is missing, the large shell has writing, the screw hole is damaged, the shaft is damaged, the gear is oxidized, the large shell is missing tapping, the screw hole has foreign matter, the gear is damaged and other defect items are detected. The specific detection method is as follows:

[0005] A. The motor to be tested is transferred to the conveyor rail by a vibrating loading tray. After the sensing mechanism on the conveyor rail detects the motor, the conveyor rail is started and the motor is transferred to the first testing station;

[0006] B. The first detection station consists of three cameras. Camera 1 detects defective terminal height and defective coding magnet height. Camera 2 detects missing tapping on the large shell. Camera 3 mainly takes pictures of the terminal magnet part to perform an internal operation and output an offset angle to the machine to rotate by an angle to take pictures of the second terminal as a prerequisite. The system records the shooting data of the three cameras and controls the conveying track to transfer the motor to the second detection station;

[0007] C. One camera is set in the second detection station and takes pictures of the motor twice. It mainly detects missing coding magnets, one of the clamping claws of the motor not clamping the small shell, the motor missing a clamping claw, missing installation of coding magnets, and damage to the small shell. After the shooting is completed, the system records the data and controls the conveying track to transfer the motor to the third detection station;

[0008] D. One camera is set in the third detection station and takes pictures of the motor twice. It mainly detects shaft damage, gear oxidation, foreign objects in the screw hole, gear damage, and screw hole damage. After completion, the system records the data and continues to control the conveying track to transfer the motor to the fourth detection station;

[0009] E. One camera is set in the fourth detection station. The camera is located above the conveying track and the shooting angle is vertically downward. When the motor is transferred directly below the camera, the rotating mechanism on one side of the conveying track drives the motor to rotate one circle, and the camera takes pictures. It mainly detects the label being pasted backwards, missing or dirty label QR code, the QR code and the label edge size not being within the specification range, repeated label pasting, the label being pasted in the wrong position, the label being pasted crooked, missing label pasting, and the large shell having handwriting. After the shooting is completed, the system records it, and the conveying track sends the motor out of the fourth detection station;

[0010] F. The system compares the shooting data of the first to fourth detection stations to determine whether there are defects in the motor, and transfers the motor to the corresponding good product box or defective product box according to the judgment result.

[0011] Further, the first detection station consists of a positioning camera, a measurement camera, and a first detection camera. The positioning camera is set on one side of the conveying track and the shooting angle is horizontally aligned with the conveying track; the measurement camera is set directly above the conveying track and the shooting angle is vertically aligned with the conveying track; the first detection camera is set on the other side of the conveying track corresponding to the positioning camera and the shooting angle is that the lens is tilted downward by 45° and aligned with the conveying track. An output angle stepping motor is also set at the positions of the conveying track corresponding to the measurement camera and the first detection camera.

[0012] Still further, detection method B is divided into the following two steps:

[0013] a. The positioning camera works first, identifying the magnet part behind the motor. After calculating the angle through the reference line and reference angle and outputting the angle, the measurement camera starts to photograph the height of the first pin of the motor. At the same time, the first detection camera starts to detect whether the screw holes of the motor are tapped.

[0014] b. The output angle stepping motor swings to the lower part of the motor. At this time, the first roller arranged on the output angle stepping motor contacts the motor. The first roller rotates under the control of the output angle stepping motor, driving the motor to rotate and turn over. The measurement camera starts to photograph the height of the second pin of the motor and the height of the magnet behind. At the same time, the first detection camera starts to detect whether the screw holes on the other side of the motor are tapped.

[0015] Furthermore, the second detection station consists of a second detection camera and a first air cylinder. The second detection camera is arranged on one side of the conveying rail, and the shooting angle is horizontally aligned with the conveying rail. The second detection camera is connected to the output end of the first air cylinder. After the motor is transported to the second detection station, the second detection camera takes the first photo of the motor to detect the missing coding magnet and the missed installation of the coding magnet. After the first photo is completed, the first air cylinder pushes the second detection camera forward and backward for the second photo. The second photo is to detect whether there is a situation where one of the clamping claws of the motor does not hold the small shell, the motor is missing a clamping claw, or the small shell is damaged.

[0016] Moreover, the third detection station consists of a third detection camera and a second air cylinder. The third detection camera is connected to the output end of the second air cylinder and is arranged on one side of the conveying rail. The shooting angle of the third detection camera is horizontally aligned with the conveying rail. When the motor is transported to the third detection station, the third detection camera takes the first photo to detect problems such as damage to the motor shaft, oxidation of the gear, and damage to the gear. Subsequently, the second air cylinder pushes the third detection camera towards the motor and takes the second photo to detect whether there are foreign objects in the screw holes of the motor.

[0017] Finally, the fourth detection station consists of a line scan camera, a third air cylinder, and a second roller. The line scan camera is arranged above the conveying rail, and the shooting angle is vertically aligned with the conveying rail. The third air cylinder is arranged below the line scan camera and on one side of the conveying rail. The second roller is arranged on the output end of the third air cylinder. When the motor is transported to the fourth detection station, the third air cylinder rises until the second roller contacts the motor. The roller rotates, driving the motor to rotate one circle, and the line scan camera takes a photo for defect detection.

[0018] The beneficial effects of the present invention are as follows: Through multi-station and multi-camera detection, the appearance surface of the motor can be comprehensively and frequently sampled quickly. While ensuring the accuracy of photo sampling, the system algorithm is used to compare and detect whether the appearance of the motor is qualified, and the detection results are stored for subsequent production and processing work. The present invention uses vision detection technology for measurement. The motor is photographed and sampled at up to six different angles through the first detection station, the second detection station, the third detection station, and the fourth detection station. Defect items such as small shell damage, terminal deformation, reverse installation of coding magnets, poor terminal height, one of the clamping claws of the motor not clamping the small shell, missing clamping claws of the motor, missing coding magnets, poor coding magnet height, missing installation of coding magnets, reverse label pasting, missing or dirty label QR code, the edge size of the QR code and the label not within the specification range, repeated label pasting, wrong label pasting position, crooked label pasting, missing label pasting, writing on the large shell, screw hole damage, shaft damage, gear oxidation, missing tapping of the large shell, foreign objects in the screw hole, gear damage, etc. are detected, replacing the manual visual inspection method, with the advantages of high precision, fast speed, and long working hours. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a flowchart of the present invention;

[0020] Figure 2 is a flowchart of the first detection station;

[0021] Figure 3 is a flowchart of the second detection station;

[0022] Figure 4 is a flowchart of the third detection station;

[0023] Figure 5 is a flowchart of the fourth detection station. DETAILED DESCRIPTION OF THE INVENTION

[0024] The present invention is carried out using four detection stations. The motor is sequentially sent to the four detection stations through a conveying mechanism for detecting defect items such as small shell damage, terminal deformation, reverse installation of coding magnets, poor terminal height, one of the clamping claws of the motor not clamping the small shell, missing clamping claws of the motor, missing coding magnets, poor coding magnet height, missing installation of coding magnets, reverse label pasting, missing or dirty label QR code, the edge size of the QR code and the label not within the specification range, repeated label pasting, wrong label pasting position, crooked label pasting, missing label pasting, writing on the large shell, screw hole damage, shaft damage, gear oxidation, missing tapping of the large shell, foreign objects in the screw hole, gear damage, etc. The specific detection method is as follows:

[0025] A. The motor to be tested is conveyed to the conveying rail through a vibrating feeding tray. After the induction mechanism on the conveying rail detects the motor, the conveying rail starts and transports the motor to the first detection station;

[0026] B. The first inspection station is composed of three cameras. Camera 1 detects poor terminal height and poor encoding magnet height. Camera 2 detects large shell tapping. Camera 3 mainly photographs the terminal magnet part to perform an internal calculation and output an offset angle to give the machine a rotation angle to photograph the second terminal as a prerequisite. The system records the shooting data of the three cameras and controls the conveyor rail to transmit the motor to the second inspection station.

[0027] C. A camera is provided in the second inspection station, and the motor is photographed twice, mainly to detect whether the coding magnet is missing, one of the motor's pressing claws does not hold the small shell, the motor has missing pressing claws, the coding magnet is missing, and the small shell is damaged. After the shooting is completed, the system records the data and controls the conveyor rail to transfer the motor to the third inspection station;

[0028] D. A camera is provided in the third inspection station, and the motor is photographed twice, mainly to detect shaft damage, gear oxidation, foreign matter in screw holes, gear damage, and screw hole damage. After completion, the system records the data and continues to control the conveyor rail to transfer the motor to the fourth inspection station;

[0029] E. A camera is provided in the fourth inspection station. The camera is located above the conveyor rail with a shooting angle vertically downward. When the motor is transmitted to the bottom of the camera, the rotating mechanism located on one side of the conveyor rail drives the motor to rotate one circle, and the camera takes pictures. The main inspections are to detect labels that are pasted upside down, labels with missing or dirty QR codes, QR codes and label edge sizes that are not within the specification range, repeated labeling, labels in the wrong position, labels that are crooked, labels that are missing, and large shells with writing. After the shooting is completed, the system records it, and the conveyor rail sends the motor out of the fourth inspection station;

[0030] F. The system compares the captured data from the first to fourth inspection stations to determine whether the motor is defective, and transfers the motor to the corresponding good product box or defective product box based on the determination result.

[0031] In this embodiment, the first detection station is composed of a positioning camera, a measurement camera, and a first detection camera. The positioning camera is arranged on one side of the conveying rail, and its shooting angle is horizontally aligned with the conveying rail. The measurement camera is arranged directly above the conveying rail, and its shooting angle is vertically aligned with the conveying rail. The first detection camera is arranged on the other side of the conveying rail corresponding to the positioning camera, and its shooting angle is 45° downward with the lens aligned with the conveying rail. An output angle stepping motor is also arranged on the conveying rail at positions corresponding to the measurement camera and the first detection camera. The first detection station is composed of three area array cameras. The measurement camera is a 5-megapixel black-and-white camera equipped with a telecentric lens and a bar light source. The first detection camera is a 2-megapixel black-and-white camera equipped with an FA lens and a bar light source. The positioning camera is a 2-megapixel black-and-white camera equipped with an FA lens and an annular light source.

[0032] The detection method B is divided into the following two steps:

[0033] a. The positioning camera works first to identify the characteristics of the magnet part behind the motor. After calculating the output angle through the reference line and reference angle, the measurement camera starts to shoot the height of the first pin of the motor. At the same time, the first detection camera starts to detect whether the screw holes of the motor are tapped.

[0034] b. The output angle stepping motor swings below the motor. At this time, the first roller arranged on the output angle stepping motor contacts the motor. The first roller rotates under the control of the output angle stepping motor to drive the motor to rotate and turn over. The measurement camera starts to shoot the height of the second pin of the motor and the height of the magnet behind. At the same time, the first detection camera starts to detect whether the screw holes on the other side of the motor are tapped.

[0035] The second detection station consists of a second detection camera and a first air cylinder. The second detection camera is arranged on one side of the conveying rail, and its shooting angle is horizontally aligned with the conveying rail. The second detection camera is connected to the output end of the first air cylinder. After the motor is transported to the second detection station, the second detection camera takes the first photo of the motor to detect the absence of the coded magnet or the missed installation of the coded magnet. After the first photo is taken, the first air cylinder pushes the second detection camera forward and backward for the second photo. The second photo is used to detect whether one of the clamping claws of the motor fails to hold the small shell, whether the motor has a missed clamping claw, and whether the small shell is damaged. In this embodiment, the second detection station consists of a single area array camera. The second detection camera is a 5-megapixel black and white camera equipped with an FA lens and a ring light source. When the first detection station completes the detection work and outputs an OK signal, the motor is transported onto this station along the conveying rail. The second detection camera takes two photos. The first photo is used to detect the absence of the motor magnet and the missed installation of the coded magnet. The second photo is used to detect damage to the small shell, whether one of the clamping claws of the motor fails to hold the small shell, and whether the motor has a missed clamping claw. Since the detection positions are different, there is a phenomenon of depth of field difference in optics. Therefore, after the second detection camera takes the first photo, the first air cylinder will push the second detection camera forward (i.e., towards the motor) to move its position for the second photo, thus solving the problem of depth of field difference.

[0036] The third detection station consists of a third detection camera and a second air cylinder. The third detection camera is connected to the output end of the second air cylinder and is arranged on one side of the conveying rail. The shooting angle of the third detection camera is horizontally aligned with the conveying rail. When the motor is transported to the third detection station, the third detection camera takes the first photo to detect problems such as damage to the motor shaft, oxidation of the gear, and damage to the gear. Subsequently, the second air cylinder pushes the third detection camera towards the motor and takes the second photo to detect whether there are foreign objects in the motor screw holes. The third detection station consists of a single area array camera. The third detection camera is a 5-megapixel color camera equipped with an FA lens and a coaxial light source (ring light source). When the first detection station and the second detection station complete the detection and output an OK signal, this station starts to work. The third detection camera also takes two photos. When taking the first photo, it detects damage to the motor shaft, oxidation of the gear, and damage to the gear. After completion, the second air cylinder is activated to push the third detection camera closer to the motor for the second photo, thereby solving the problem of depth of field difference. When taking the second photo, it detects whether there are foreign objects and damage to the screw holes in the motor screw holes.

[0037] The fourth detection station consists of a line scan camera, a third cylinder, and a second roller. The line scan camera is arranged above the conveying rail, and its shooting angle is vertically aligned with the conveying rail. The third cylinder is arranged below the line scan camera and on one side of the conveying rail. The second roller is arranged on the output end of the third cylinder. When the motor is conveyed to the fourth detection station, the third cylinder rises until the second roller contacts the motor, and the roller rotates to drive the motor to rotate one circle, while the line scan camera takes pictures for defect detection. In this embodiment, the fourth detection station consists of a line array camera, and the line scan camera is a 4K line array camera equipped with a line scan lens and a line scan light source (bar-shaped light source). When the first detection station, the second detection station, and the third detection station complete the detection and the system outputs an OK signal, this station starts to work. At this time, the third cylinder drives the second roller to rise until it contacts the motor and drives the second roller to rotate. The motor rotates driven by the second roller, and the line scan camera starts to take pictures. This picture-taking mainly detects label reversal, missing or dirty label QR codes, QR code and label edge dimensions not within the specification range, repeated labeling, wrong label placement, crooked label, missing label, handwriting on the large shell, and deformed terminals.

[0038] Finally, it should be emphasized that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for visual inspection of an electric motor, characterized in that: This detection method adopts four detection stations. The motor is transmitted to the four detection stations in turn through the transmission mechanism to detect the defects of small shell damage, terminal deformation, reverse installation of the coding magnet, poor terminal height, one of the motor's pressure claws not holding the small shell, motor missing pressure claws, missing coding magnets, poor coding magnet height, missing coding magnets, reversed labels, missing or dirty QR codes on labels, QR code and label edge dimensions not within the specification range, repeated labeling, wrong label positions, crooked labels, missing labels, writing on the large shell, screw hole damage, shaft damage, gear oxidation, missing tapping on the large shell, foreign matter in the screw holes, and gear damage. The specific detection method is as follows: The motor to be tested is transmitted to the conveyor rail by a vibrating loading tray. After the induction mechanism on the conveyor rail detects the motor, the conveyor rail starts and transmits the motor to the first detection station; The first detection station is composed of three cameras. Camera 1 detects poor terminal height and poor coding magnet height. Camera 2 detects missing tapping on the large shell. Camera 3 mainly takes pictures of the terminal magnet part, performs an internal calculation, and outputs an offset angle. The machine is turned to an angle to prepare for photographing the second terminal. The system records the shooting data of the three cameras and controls the conveyor rail to transfer the motor to the second inspection station. A camera is provided in the second inspection station, and the motor is photographed twice, mainly to detect whether the coding magnet is missing, one of the motor's pressing claws does not hold the small shell, the motor has missing pressing claws, the coding magnet is missing, and the small shell is damaged. After the shooting is completed, the system records the data and controls the conveyor rail to transfer the motor to the third inspection station. A camera is provided in the third inspection station, and the motor is photographed twice, mainly to detect shaft damage, gear oxidation, foreign matter in the screw hole, gear damage, and screw hole damage. After completion, the system records the data and continues to control the conveyor rail to transfer the motor to the fourth inspection station. A camera is provided in the fourth inspection station. The camera is located above the conveyor rail with a shooting angle vertically downward. When the motor is transmitted to the bottom of the camera, the rotating mechanism located on one side of the conveyor rail drives the motor to rotate one circle, and the camera takes pictures. It mainly detects whether the label is pasted upside down, the QR code of the label is missing or dirty, the size of the QR code and the label edge is not within the specification range, repeated labeling, the label is pasted in the wrong position, the label is pasted crookedly, the label is missing, and there are words on the large shell. After the shooting is completed, the system records it, and the conveyor rail sends the motor out of the fourth inspection station; The system compares the shooting data of the first to fourth inspection stations to determine whether the motor has defects, and transfers the motor to the corresponding good product box or defective product box according to the judgment result; The first detection station consists of a positioning camera, a measurement camera, and a first detection camera. The positioning camera is set on one side of the conveying track, with its shooting angle horizontally aligned with the conveying track. The measurement camera is set directly above the conveying track, with its shooting angle vertically aligned with the conveying track. The first detection camera is set on the other side of the conveying track corresponding to the positioning camera, with its shooting angle tilted downward by 45° with the lens aligned with the conveying track. An output angle stepping motor is also set at the positions corresponding to the measurement camera and the first detection camera on the conveying track. The detection method is divided into the following two steps: First, the positioning camera works to identify the characteristics of the magnet part behind the motor. After calculating the output angle through the reference line and reference angle, the measurement camera starts to photograph the height of the first pin of the motor. At the same time, the first detection camera starts to detect whether the motor screw holes are tapped. The output angle stepping motor swings below the motor. At this time, the first roller set on the output angle stepping motor contacts the motor, and the first roller rotates under the control of the output angle stepping motor to drive the motor to rotate and turn over. The measurement camera starts to photograph the height of the second pin of the motor and the height of the magnet behind it. At the same time, the first detection camera starts to detect whether the screw holes on the other side of the motor are tapped. The second detection station consists of a second detection camera and a first air cylinder. The second detection camera is set on one side of the conveying track, with its shooting angle horizontally aligned with the conveying track. The second detection camera is connected to the output end of the first air cylinder. After the motor is transported to the second detection station, the second detection camera takes the first photo of the motor to detect the missing coding magnet and the missed installation of the coding magnet. After the first photo is completed, the first air cylinder pushes the second detection camera forward and backward to take the second photo. The second photo is for detecting whether one of the clamping claws of the motor fails to hold the small shell, the motor has a missed clamping claw, or the small shell is damaged. The third detection station consists of a third detection camera and a second air cylinder. The third detection camera is connected to the output end of the second air cylinder and is set on one side of the conveying track. The shooting angle of the third detection camera is horizontally aligned with the conveying track. When the motor is transported to the third detection station, the third detection camera takes the first photo to detect problems such as motor shaft damage, gear oxidation, and gear damage. Subsequently, the second air cylinder pushes the third detection camera towards the motor and takes the second photo to detect whether there are foreign objects in the motor screw holes. The fourth detection station consists of a line scan camera, a third air cylinder, and a second roller. The line scan camera is set above the conveying track, with its shooting angle vertically aligned with the conveying track. The third air cylinder is set below the line scan camera and on one side of the conveying track. The second roller is set on the output end of the third air cylinder. When the motor is transported to the fourth detection station, the third air cylinder rises until the second roller contacts the motor, and the roller rotates to drive the motor to rotate one circle. The line scan camera takes a photo for defect detection.

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