CN105181709A - Combined multiple-light-source on-line detection device and method for appearance defects of brake pad - Google Patents

Abstract

The invention discloses a combined multi-light source on-line detection device and method for appearance defects of brake pads. The DC motor and speed controller are connected to the conveyor belt, and the bracket is installed on the base. The industrial camera module, coaxial light source module and ring light source module are installed on the bracket above the conveyor belt, and the backlight light source module is installed between the upper and lower belt surfaces of the conveyor belt; A pneumatic push rod and a defective product receiving box are installed near the side edge of the belt, and the pneumatic push rod is connected to the air compressor through a solenoid valve; it also includes a PLC controller, a relay module and a computer. The invention constitutes a complete automatic detection line for surface defects of brake pads, which can detect different types of defects on the surface of brake pads, and realize real-time online detection, which improves the shortcomings of the previous multi-station detection that occupies a large area and low efficiency, and realizes multi-tasking The integration of bit detection reduces equipment costs and labor costs and improves work efficiency.

Description

Combined multi-light source online detection device and method for brake pad appearance defects

technical field

The invention relates to an online detection device and method, in particular to a combined multi-light source online detection device and method for appearance defects of brake pads, which uses machine vision technology to detect appearance defects of brake pads.

Background technique

Brake pad is a common name for brake lining, which is the friction material that contacts the brake drum (disc). When the driver has a braking action, the brake pads are under pressure and generate friction with the brake drum (disc), so as to achieve the purpose of vehicle deceleration. Brake pads are an important safety part of the vehicle braking system, and their quality directly affects the braking performance of the vehicle, and is related to the safety of life and property of the vehicle drivers and passengers.

In the industrial production line, in order to meet the two-way requirements of production speed and product quality, it is necessary to cooperate with each process on the production line to do a good job in the detection of performance indicators such as appearance and size. For brake pads, which have many types of defects and the defects are not obvious, manual inspection needs to detect surface defects of brake pads by hand, visual, light reflection, light projection and other methods. Due to factors such as visual fatigue and emotional fluctuations of quality inspection workers, the traditional method has poor quality standards, slow detection speed, and low efficiency. At the same time, for brake pads, which have many inspection items, traditional machine vision inspection can only detect a certain type of defect, while the multi-station inspection system has high equipment cost and low efficiency. Therefore, in the production of brake pads The industry urgently needs a combined multi-light source appearance defect online detection device.

Contents of the invention

In order to solve the problems in the background technology, the object of the present invention is to provide a combined multi-light source on-line inspection device and method for appearance defects of brake pads, which can be used for non-contact and non-destructive on-line detection of appearance defects of brake pads on the production line.

In order to achieve the above object, the technical solution adopted in the present invention is:

1. A combined multi-light source online detection device for appearance defects of brake pads:

Including the conveyor belt for transferring brake pads, DC motor and governor, defective product receiving box, photoelectric switch, air compressor, solenoid valve and pneumatic push rod; the DC motor and governor are connected to the drive shaft on one side of the conveyor belt The drive rotates to drive the conveyor belt to run. The bracket is fixed and installed vertically on the base placed on the ground. The bracket is located on the side of the conveyor belt. The industrial camera module, coaxial light source module and ring light source module are installed on the bracket above the conveyor belt. A backlight light source module is installed between the surfaces;

A pneumatic push rod for pushing unqualified brake pads is installed near the edge of one side of the belt surface on the conveyor belt. The pneumatic push rod is located directly below the ring light source module. The product receiving box, the photoelectric switch is installed on the top of the pneumatic push rod through the photoelectric switch frame, and the pneumatic push rod is connected with the air compressor through the solenoid valve.

The industrial camera module includes an industrial camera, a quick release plate, a camera fixing block and a camera adjustment device for adjusting the height of the industrial camera up and down and horizontally. The industrial camera is installed on the camera adjustment device through the quick release plate, and the base of the camera adjustment device is connected to the The camera fixing block is fixedly connected, and the camera fixing block is fixedly installed on the bracket through the connecting block rod structure; the coaxial light source module includes a coaxial light source and a coaxial light source fixing block, and the coaxial light source is fixed on the coaxial light source by bolts. On the block, the coaxial light source fixing block is fixedly installed on the bracket through the connecting block rod structure; the ring light source module includes a ring light source and a ring light source fixing block, the ring light source is fixed on the ring light source fixing block by bolts, and the ring light source is fixed The block is fixedly installed on the bracket through the connecting block rod structure; the backlight light source module includes a backlight light source and a backlight light source fixing block, the backlight light source is fixed and installed on the backlight light source fixing block through bolts, and the backlight light source fixing block is fixed through the connecting block rod structure Installed on the bracket, the light source 29 passes through the horizontal channel through the connecting block rod structure; the industrial camera, coaxial light source, ring light source and backlight light source are installed coaxially in sequence, and the industrial camera faces directly downward.

The camera adjustment device includes a y-direction fixing block, a y-direction sliding bar, an x-direction fixing block and an x-direction sliding bar, the quick release plate is fixedly connected with the horizontal x-direction sliding bar, and the x-direction sliding bar is embedded in the x-direction fixing block The sliding pair is formed in the upper horizontal dovetail groove, the x-direction fixed block is fixedly connected with the y-direction slider, the dovetail groove on the y-direction slider is matched with the y-direction fixed block to form a sliding pair, the y-direction fixed block is connected with the camera The fixed block is fixedly connected.

It also includes PLC controller, relay module and computer. DC motor and speed controller, coaxial light source, ring light source and backlight light source are all connected to PLC controller through relay module. Photoelectric switch and solenoid valve are connected to PLC controller. Both the camera and the PLC controller are connected with the computer.

The industrial camera is an industrial grade area scan cmos camera.

The belt surface of the conveyor belt is made of transparent material.

The brake pad occupies 2/3-3/4 of the field of view of the industrial camera. The coaxial light source module is located under the industrial camera. Its optical axis coincides with the optical axis of the industrial camera lens, and the coaxial light source can evenly illuminate the brake pad and its surrounding area. Its optical axis coincides with the optical axis of the industrial camera. The ring light source module is located at a proper position below the coaxial light source module, and its optical axis coincides with the optical axis of the coaxial light source, and the ring light source can illuminate both edges of the brake pad. The backlight light source module is located below the ring light source module, and its optical axis coincides with the optical axis of the ring light source.

2. A combined multi-light source online detection method for appearance defects of brake pads:

1) Using the above device, first calibrate the industrial camera;

2) The front image of the qualified brake pad is collected by the calibrated industrial camera and processed to make a brake pad template. The front image of the qualified brake pad includes the contour image and the edge image at both ends. The brake pad template is used for subsequent steps to detect the appearance defects of the brake pad matching;

3) The brake pads are transported by the conveyor belt. When the brake pads are detected when they are transported to the photoelectric switch, the PLC controller controls the DC motor to stop rotating;

4) The PLC controller collects the profile image of the brake pad by controlling the backlight source and the industrial camera, and processes the brake pad through the pneumatic push rod according to the detection result after image processing;

5) The PLC controller collects the edge images of both ends of the brake pad by controlling the ring light source and the industrial camera, and after image processing, the brake pad is processed by the pneumatic push rod according to the detection result;

The PLC controller collects the surface image of the brake pad by controlling the coaxial light source and the industrial camera, and after image processing, the brake pad is processed through the pneumatic push rod according to the detection result;

The PLC controller controls to turn off the coaxial light source, controls to turn on the DC motor, and the DC motor drives the conveyor belt to the left to complete the online detection of various defects of the brake pads.

Described step 4) is specifically as follows: the PLC controller controls to turn on the backlight source, the PLC controller triggers the industrial camera to collect the contour image of the brake pad, processes the collected contour image, and obtains the result of whether the brake pad contour is complete: if the brake If the outline of the brake pad is complete, proceed to the next step, otherwise the PLC controller controls the pneumatic push rod to push the brake pad into the defective product receiving box, and returns to step 3) for the next detection of the brake pad.

The step 5) is specifically as follows: the PLC controller controls to turn off the backlight light source, controls to turn on the ring light source, and the PLC controller triggers the industrial camera to collect the edge images at both ends of the brake pad, and processes the collected edge images at both ends to obtain the brake pad. Result of whether the stamped characters on both ends of the brake pad are complete: if the stamped characters on both ends of the brake pad are complete, proceed to the next step, otherwise the PLC controller controls the pneumatic push rod to push the brake pad into the defective product receiving box, and return to the step 3) Carry out the detection of the next brake pad.

The step 6) is specifically as follows: the PLC controller controls to turn off the ring light source, controls to turn on the coaxial light source, the PLC controller triggers the industrial camera to collect the surface image of the brake pad, and after processing the collected surface image, the surface of the brake pad is obtained. The result of whether the defect size is qualified: if the defect size on the surface of the brake pad is qualified, proceed to the next step, otherwise the PLC controller controls the pneumatic push rod to push the brake pad into the defective product receiving box, and returns to step 3) for the next brake slice detection.

The invention detects whether there is a brake pad on the rotating conveyor belt through a photoelectric switch installed above the rear crossbeam of the conveyor belt. If there is, the PLC controller controls the conveyor belt to stop transmission, and the PLC controller turns on the light sources on the combined multi-light source visual detection frame in turn. , when the light source is turned on, the industrial camera on the combined multi-light source visual inspection frame is triggered to take pictures, and the pictures are transmitted to the computer, and the image processing program is used to judge whether there are appearance defects in the brake pads. If there are, it communicates with the PLC controller and controls the The pneumatic push rod pushes the brake pads to the defective product receiving box, and if there is no appearance defect, it will continue to be conveyed along the conveyor belt.

Compared with background technology, the beneficial effect that the present invention has is:

The invention constitutes a complete automatic detection assembly line for surface defects of brake pads, replaces the original low-reliability and low-efficiency manual detection, and enables the original complicated detection process to be automatically completed on an automatic detection assembly line.

The invention can detect different types of defects on the surface of the brake pads through the setting of different light sources, and realize real-time online detection, which improves the shortcomings of the previous multi-station detection that occupies a large area and low efficiency, realizes the integration of multi-station detection, reduces the Equipment costs are reduced, labor costs are reduced, and work efficiency is improved.

Description of drawings

Fig. 1 is the general assembly drawing of the device of the present invention.

Fig. 2 is a structural schematic diagram of the device of the present invention.

Fig. 3 is a schematic diagram of the installation of the ring light source, the coaxial light source and the camera of the present invention.

Fig. 4 is a schematic diagram of the installation of the backlight light source of the present invention.

Fig. 5 is the electrical control connection diagram of the present invention.

Fig. 6 is a detection flowchart of the method of the present invention.

In the figure, 1. Conveyor belt, 2. DC motor and governor, 3. Receiving box for defective products, 4. Photoelectric switch, 5. PLC controller, 6. Relay module, 7. Computer, 8. Air compressor, 9. Solenoid valve, 10. Pneumatic push rod, 11. Coaxial light source fixing block, 12. Base, 13. Bracket, 14. Industrial camera, 15. Camera adjustment device, 16. Quick release plate, 17. Coaxial light source Module, 18, ring light source module, 19, backlight light source module, 20, camera fixing block, 21, connecting block, 22, connecting rod, 23, y-direction fixing block, 24, y-direction slide bar, 25, x-direction fixing block , 26, x direction slide bar, 27, coaxial light source, 28, ring light source, 29, backlight light source, 30, photoelectric switch frame, 31, ring light source fixing block, 32, backlight light source fixing block.

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figure 1, the present invention comprises the conveyer belt 1 that is used to transmit brake pad, DC motor and governor 2, defective product receiving box 3, photoelectric switch 4, electromagnetic valve 9 and pneumatic push rod 10; Speed 2 is connected to the driving shaft on one side of conveyor belt 1 to drive and rotate to drive conveyor belt 1 to run. Bracket 13 is vertically and fixedly installed on base 12 placed on the ground. Bracket 13 is located on the side of conveyor belt 1. An industrial camera module, a coaxial light source module 17 and a ring light source module 18 are installed, and a backlight light source module 19 is installed between the upper and lower belt surfaces of the conveyor belt 1 .

As shown in Figure 2, a pneumatic push rod 10 for pushing unqualified brake pads is installed near the edge of one side of the conveyor belt 1. The pneumatic push rod 10 is located directly below the ring light source module 18. 1. The other side edge of the upper belt surface is installed with a defective product receiving box 3 for accommodating unqualified brake pads. The photoelectric switch 4 is installed on the top of the pneumatic push rod 10 through the photoelectric switch frame 30. The pneumatic push rod 10 is connected with the solenoid valve 9 and The air compressor 8 is connected, and the solenoid valve 9 is installed on the edge of the conveyor belt 1 on the same side as the pneumatic push rod 10 .

As shown in Figure 5, the present invention also includes PLC controller 5, relay module 6 and computer 7, DC motor and governor 2, coaxial light source 27, ring light source 28 and backlight light source 29 are all controlled by relay module 6 and PLC Device 5 is connected, photoelectric switch 4, electromagnetic valve 9 are all connected with PLC controller 5, industrial camera 14 and PLC controller 5 are all connected with computer 7.

As shown in Figure 3, the industrial camera module includes an industrial camera 14, a quick release plate 16, a camera fixing block 20, and a camera adjustment device 15 for adjusting the height of the industrial camera 14 up and down and horizontally, and the industrial camera 14 is installed on the industrial camera 14 through the quick release plate 16. On the camera adjustment device 15, the camera adjustment device 15 can specifically adopt a slider guide rail structure, the quick release plate 16 is fixed to the camera adjustment device 15 through bolts, the base of the camera adjustment device 15 is fixedly connected to the camera fixing block 20, and the camera fixing block 20 is connected by The block rod structure is fixedly installed on the support 13, and the connecting block rod structure includes a connecting block 21 and a connecting rod 22;

As shown in Figure 3, the coaxial light source module 17 includes a coaxial light source 27 and a coaxial light source fixing block 11. The rod structure is fixedly mounted on the support 13 .

As shown in Figure 3, the ring light source module 18 includes a ring light source 28 and a ring light source fixing block 31, the ring light source 28 is fixed on the ring light source fixing block 31 by bolts, and the ring light source fixing block 31 is fixed on the bracket through the connecting block rod structure 13 on.

As shown in Figure 4, the backlight light source module 19 includes a backlight light source 29 and a backlight light source fixing block 32, the backlight light source 29 is fixedly installed on the backlight light source fixing block 32 by bolts, and the backlight light source fixing block 32 is fixedly installed on the bracket through the connecting block rod structure 13 on. In specific implementation, the side of the conveyor belt 1 is also equipped with a beam along the conveying direction, and the beam side is provided with a horizontal channel along the conveying direction.

Adjust the structure of the connecting block and the connecting rod so that the industrial camera 14, the coaxial light source 27, the ring light source 28 and the backlight light source 29 are installed coaxially in sequence, and the optical axes of the industrial camera 14, the coaxial light source 27, the ring light source 28 and the backlight light source 29 coincide, The industrial camera 14 faces directly below, and the structure of the connecting block and the connecting rod is adjusted so that the coaxial light source 27 can evenly irradiate the entire brake pad and its surrounding area on the conveyor belt 1 directly below, and the ring light source 28 irradiates the edges of both ends of the brake pad.

The camera adjustment device 15 includes a y-direction fixing block 23, a y-direction sliding bar 24, an x-direction fixing block 25 and an x-direction sliding bar 26. The quick release plate 16 is fixedly connected to the horizontal x-direction sliding bar 26, and the x-direction sliding bar 26 is embedded The sliding pair is formed in the horizontal dovetail groove on the x-direction fixed block 25, the x-direction fixed block 25 is fixedly connected with the y-direction slide bar 24, and the dovetail groove on the y-direction slide bar 24 is matched with the y-direction fixed block 23 A sliding pair is formed, and the y-direction fixed block 23 is fixedly connected with the camera fixed block 20 .

The industrial camera 14 is an industrial-grade area array cmos camera, the industrial camera 14 is connected to the computer 7 through usb3.0, and the PLC controller 5 and the computer 7 are connected to communicate through a serial port.

The belt surface of the conveyor belt 1 is made of transparent material, the annular light source 28 adopts a high-angle direct lighting method, and the backlight light source 29 adopts a parallel backlight light source.

Specifically, the DC motor and the governor 2 are connected to the PLC controller 5 and the power supply through one path of the relay module 6, and the coaxial light source 27, the ring light source 28 and the backlight light source 29 are respectively controlled by the PLC through the other three paths of the relay module 6. The solenoid valve 9 is connected with the pneumatic push rod 10, the output end of the PLC controller 5 and the air compressor 8 respectively, and the photoelectric switch 4 is connected with the input end of the PLC controller 5.

Referring to Fig. 6, the detection process of the specific implementation of the present invention is:

1) The industrial camera can be calibrated by using the open source function of halcon;

2) The calibrated industrial camera is set in the external trigger state, and a frontal image of a qualified brake pad is collected by the external trigger for image enhancement and image segmentation processing to make a brake pad template, which is used in subsequent steps to detect the appearance defects of the brake pad matching;

3) The brake pads are transmitted by the conveyor belt. When the brake pads are detected when they are transmitted to the photoelectric switch, the PLC controller 5 controls the first channel of the relay module to be disconnected so that the DC motor stops rotating;

4) The PLC controller 5 controls the second channel of the relay module to turn on the backlight source, and the PLC controller 5 triggers the industrial camera to collect the contour image of the brake pad, and performs image enhancement, image segmentation, edge detection, and edge detection on the collected contour image in sequence. Concatenation, contour search and template matching processing to obtain the result of whether the brake pad contour is complete:

If the outline of the brake pads is complete, proceed to the next step, otherwise the computer communicates with the PLC controller 5, and the PLC controller 5 controls the solenoid valve to make the air compressor and the pneumatic push rod conduct, and the pneumatic push rod pushes the brake pads into the defective product collection. Material box, return to step 3) to carry out the detection of next brake pad;

5) The PLC controller 5 controls the second channel of the relay module to disconnect and turn off the backlight source, and controls the third channel of the relay module to turn on and turn on the ring light source. The PLC controller 5 triggers the industrial camera to collect the edge images of both ends of the brake pad. Image enhancement, image segmentation, character segmentation, and template matching are performed on the edge images at both ends of the brake pad to obtain the result of whether the stamped characters on both ends of the brake pad are complete:

If the stamped characters on both ends of the brake pad are complete, proceed to the next step, otherwise the computer communicates with the PLC controller 5, and the PLC controller 5 controls the solenoid valve to make the air compressor and the pneumatic push rod conduct, and the pneumatic push rod pushes the brake The disc enters the defective product receiving box, and returns to step 3) to carry out the detection of the next brake disc;

6) The PLC controller 5 controls the third channel of the relay module to disconnect and turn off the ring light source, and controls the fourth channel of the relay module to turn on and turn on the coaxial light source. The PLC controller 5 triggers the industrial camera to collect the surface image of the brake pad, and the computer performs the collected image. After the surface image is processed by image enhancement, image segmentation, feature extraction, bolb analysis, and minimum circumscribing moment calculation, the result of whether the defect size on the surface of the brake pad is qualified or not is obtained:

If the size of the defect on the surface of the brake pad is qualified, proceed to the next step, otherwise the computer communicates with the PLC controller 5, and the PLC controller 5 controls the solenoid valve to make the air compressor conduct with the pneumatic push rod, and the pneumatic push rod pushes the brake pad into the Defective product receiving box, return to step 3) to carry out the detection of the next brake pad;

7) The PLC controller 5 controls the fourth channel of the relay module to disconnect and turn off the coaxial light source, controls the first channel of the relay module to turn on and turns on the DC motor, and the DC motor drives the conveyor belt to the left to complete the online detection of various defects of the brake pad.

Qualified brake pads are transported by the conveyor belt and placed in the qualified product receiving box.

The above-described embodiment is a kind of assembly line operation. It can be seen that the present invention is suitable for detecting surface defects of brake pads of different sizes, and realizes automatic detection of surface defects of brake pads. Compared with traditional human visual inspection methods, the detection accuracy is improved. The detection efficiency reduces the labor cost; and realizes multi-light source detection, integrates more light sources in a small space, and realizes the detection of various surface defects of brake pads. Compared with traditional multi-station detection, it saves space, reduce equipment costs, improve work efficiency, and have prominent and remarkable technical effects.

Claims (10)

1. a brake block open defect combined type multiple light courcess on-line measuring device, is characterized in that: comprise the travelling belt (1) for transmitting brake block, direct current generator and speed regulator (2), substandard products rewinding box (3), optoelectronic switch (4), air compressor (8), solenoid valve (9) and air-leg (10); Direct current generator and speed regulator (2) are connected with the main drive shaft of travelling belt (1) side to drive and rotate and drive travelling belt (1) to run, support (13) be vertically fixedly mounted on be positioned over ground pedestal (12) on, support (13) is positioned at travelling belt (1) side, the support (13) of travelling belt (1) top is provided with industrial camera module, coaxial light source module (17) and annular light source module (18), between the upper lower belt surface of travelling belt (1), back light module (19) is installed; Air-leg (10) for promoting defective brake block is installed near the upper edge, zone face side of travelling belt (1), air-leg (10) is positioned at immediately below annular light source module (18), the upper zone face opposite side edge of travelling belt (1) is provided with the substandard products rewinding box (3) for accommodating defective brake block, optoelectronic switch (4) is arranged on air-leg (10) top by optoelectronic switch frame (30), and air-leg (10) is connected with air compressor (8) through solenoid valve (9).

2. a kind of brake block open defect combined type multiple light courcess on-line measuring device according to claim 1, it is characterized in that: described industrial camera module comprises industrial camera (14), Quick-mounting board (16), camera fixed block (20) and for up and down and Level tune industrial camera (14) camera adjustments device (15) highly, industrial camera (14) is arranged on camera adjustments device (15) by Quick-mounting board (16), camera adjustments device (15) base is fixedly connected with camera fixed block (20), camera fixed block (20) is fixedly mounted on support (13) by contiguous block bar structure,

Described coaxial light source module (17) comprises coaxial light source (27) and coaxial light source fixed block (11), coaxial light source (27) is mounted by means of bolts on coaxial light source fixed block (11), and coaxial light source fixed block (11) is fixedly mounted on support (13) by contiguous block bar structure;

Described annular light source module (18) comprises annular light source (28) and annular light source fixed block (31), annular light source (28) is mounted by means of bolts on annular light source fixed block (31), and annular light source fixed block (31) is fixedly mounted on support (13) by contiguous block bar structure;

Described back light module (19) comprises back light (29) and back light fixed block (32), back light (29) is mounted by means of bolts on back light fixed block (32), and back light fixed block (32) is fixedly mounted on support (13) by contiguous block bar structure;

Described industrial camera (14), coaxial light source (27), annular light source (28) and back light (29) are coaxially installed successively, industrial camera (14) towards immediately below.

3. a kind of brake block open defect combined type multiple light courcess on-line measuring device according to claim 2, it is characterized in that: described camera adjustments device (15) comprises y to fixed block (23), y is to draw runner (24), x is to fixed block (25) and x to draw runner (26), Quick-mounting board (16) is fixedly connected with to draw runner (26) with the x of level, x is embedded into x to draw runner (26) and forms sliding pair in the dovetail groove of the upper level of fixed block (25), x is to fixed block (25) and y to draw runner (24) fixed-link, the dovetail groove that y has on draw runner (24) coordinates mutually embedding formation sliding pair with y to fixed block (23), y is fixedly connected with to fixed block (23) with camera fixed block (20).

4. a kind of brake block open defect combined type multiple light courcess on-line measuring device according to claim 2, it is characterized in that: also comprise PLC (5), relay module (6) and computing machine (7), direct current generator and speed regulator (2), coaxial light source (27), annular light source (28) is all connected with PLC (5) by relay module (6) with back light (29), optoelectronic switch (4), solenoid valve (9) is all connected with PLC (5), industrial camera (14) is all connected with computing machine (7) with PLC (5).

5. a kind of brake block open defect combined type multiple light courcess on-line measuring device according to claim 2, is characterized in that: described industrial camera (14) is technical grade face battle array cmos camera.

6. a kind of brake block open defect combined type multiple light courcess on-line measuring device according to claim 1, is characterized in that: the zone face of described travelling belt (1) adopts transparent material.

7. a brake block open defect combined type multiple light courcess online test method, is characterized in that adopting the arbitrary described device of claim 1 ~ 6:

1) first industrial camera is demarcated;

2) direct picture gathering qualified brake block by calibrated industrial camera carries out processing rear making brake block template, the direct picture of qualified brake block comprises contour images and edges at two ends image, and brake block template is used for the coupling that subsequent step detects brake block open defect;

3) brake block is transmitted by travelling belt, is detected when brake block is transferred to optoelectronic switch place, and PLC (5) controls direct current generator and stops operating;

4) PLC (5) is by controlling the contour images of back light and industrial camera collection brake block, is processed after image procossing according to testing result by air-leg to this brake block;

5) PLC (5) is by controlling the edges at two ends image of annular light source and industrial camera collection brake block, is processed after image procossing according to testing result by air-leg to this brake block;

(6) PLC (5) is by controlling the surface image of coaxial light source and industrial camera collection brake block, is processed after image procossing according to testing result by air-leg to this brake block;

(7) PLC (5) controls to close coaxial light source, controls to open direct current generator, and direct current generator drives travelling belt to transmit to the left, completes the on-line checkingi of brake block number of drawbacks.

8. a kind of brake block open defect combined type multiple light courcess online test method according to claim 7, it is characterized in that: described step 4) specific as follows: PLC (5) controls to open back light, PLC (5) triggers the contour images that industrial camera gathers brake block, the contour images collected is processed, obtains the result whether brake block profile is complete:

If brake block profile is complete, then proceed next step, otherwise PLC (5) controls air-leg promotes brake block and enter substandard products rewinding box, returns step 3) carry out the detection of next brake block.

9. a kind of brake block open defect combined type multiple light courcess online test method according to claim 7, it is characterized in that: described step 5) specific as follows: PLC (5) controls to close back light, control to open annular light source, PLC (5) triggers the edges at two ends image that industrial camera gathers brake block, the edges at two ends image collected is processed, obtain the result whether embossing seal character of brake block edges at two ends is complete: if the embossing seal character of brake block edges at two ends is complete, then proceed next step, otherwise PLC (5) controls air-leg promotion brake block and enters substandard products rewinding box, return step 3) carry out the detection of next brake block.

10. a kind of brake block open defect combined type multiple light courcess online test method according to claim 7, it is characterized in that: described step 6) specific as follows: PLC (5) controls to close annular light source, control to open coaxial light source, PLC (5) triggers the surface image that industrial camera gathers brake block, after the surface image collected is processed, obtain the result whether flaw size of disc surface is qualified: if the flaw size of disc surface is qualified, then proceed next step, otherwise PLC (5) controls air-leg promotion brake block and enters substandard products rewinding box, return step 3) carry out the detection of next brake block.