Inspection device

Abstract

To provide an inspection device which can easily detect a defective part of a workpiece.SOLUTION: An inspection device (1) includes: a robot arm (100) for changing the position and the direction of an attachment plate provided in an edge; an imaging unit (103) provided to be movable along the attachment plate, the imaging unit taking an image of the workpiece; a radiation unit (104) provided to be movable along the attachment plate, the radiation unit radiating the surface of the workpiece; and an inspection unit (202) for inspecting the surface of the workpiece on the basis of a picture taken by the imaging surface (103).SELECTED DRAWING: Figure 9

Description

[Technical field]

[0001] The present invention relates to an inspection device for inspecting a workpiece. [Background technology]

[0002] Conventionally, there has been proposed a device that captures an image of a workpiece using a digital camera or the like and inspects the surface of the workpiece for scratches, etc. An example of a related technique is the invention disclosed in Patent Document 1 below.

[0003] Patent Document 1 discloses that a camera and a light are fixed to the tip of a robot arm, and that the light uses LEDs and the camera for photographing an object is mounted so that the angle can be adjusted. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2008-46103 A (Published February 28, 2008) Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the robot arm disclosed in Patent Document 1, the positions of the lighting and camera are fixed, making it difficult to, for example, change the angle of lighting for the same position on the workpiece while keeping the robot arm fixed.

[0006] An object of one aspect of the present invention is to provide an inspection device capable of easily detecting defective portions of a workpiece. [Means for solving the problem]

[0007] In order to solve the above problems, an inspection device according to one embodiment of the present invention comprises a robot arm that can change the position and direction of a mounting plate at its tip, an imaging unit that is movable along the mounting plate and captures an image of a workpiece, an illumination unit that is movable along the mounting plate and illuminates the workpiece surface, and an inspection unit that inspects the workpiece surface based on the image captured by the imaging unit. Effect of the Invention

[0008] According to one aspect of the present invention, it is possible to easily detect defective portions of a workpiece. [Brief description of the drawings]

[0009] [Figure 1] 1 is a diagram showing an example of an external appearance of an inspection device according to an embodiment of the present invention as seen from the carriage carrying-in side; [Diagram 2] 1 is a diagram showing an example of an external appearance of an inspection device according to an embodiment of the present invention, as viewed from an operation unit side. [Diagram 3] FIG. 2 is a diagram showing an example of the inside of an inspection device according to an embodiment of the present invention. [Figure 4] FIG. 1 is a diagram illustrating an example of the appearance of a robot arm. [Diagram 5] 1A and 1B are plan and side views of a robot arm. [Figure 6] FIG. 2 is a diagram showing an example of the appearance of a dolly. [Figure 7] FIG. 13 is a diagram showing that the platform of the dolly is in a reversible state. [Figure 8] FIG. 13 is a diagram showing the platform of the dolly in a fixed state. [Figure 9] 1 is a block diagram showing an example of a functional configuration of an inspection apparatus according to an embodiment of the present invention; [Figure 10] 4 is a flowchart for explaining a processing procedure of an inspection apparatus according to an embodiment of the present invention. [Figure 11] 11 is a flowchart for explaining details of an inspection in a semi-automatic mode shown in FIG. 10. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] [Embodiment] <Appearance example of inspection device 1> Fig. 1 is a diagram showing an example of the appearance of an inspection device 1 according to an embodiment of the present invention, as seen from the side where a cart is carried in. A robot arm, which will be described later, is arranged in the inspection device 1, and a cart 300 carrying a workpiece is carried in to inspect the workpiece. Note that Fig. 1 shows a state in which the front door of the inspection device 1 is closed.

[0011] 1, a guide 500 is provided below the inspection device 1, and the carriage 300 is carried in and out along this guide 500. Therefore, the positioning of the workpiece placed on the carriage 300 can be easily performed.

[0012] Fig. 2 is a diagram showing an example of the appearance of the inspection device 1 according to the embodiment of the present invention, as viewed from the side of the operation unit 204. As described later, an operator operates the operation unit 204 to inspect a workpiece. Note that Fig. 2 shows a state in which the door on the rear side of the inspection device 1 is closed.

[0013] Fig. 3 is a diagram showing an example of the inside of an inspection device according to an embodiment of the present invention. As shown in Fig. 3, a robot arm 100 is disposed on the upper part of the inspection device 1, and a cart 300 on which a workpiece is placed is carried under the robot arm 100.

[0014] 4 is a diagram showing an example of the appearance of the robot arm 100. A mounting plate 102 is provided at the tip of the robot arm 100. The robot arm 100 is a device that can move the mounting plate 102 to any position and direction, and any well-known robot arm such as a multi-joint robot or a robot combined with a linear drive device can be used.

[0015] The mounting plate 102 is provided with an imaging unit 103 that is movably provided on the mounting plate 102 and captures an image of the workpiece to be inspected, an illumination unit 104 that is movably provided on the mounting plate 102 and illuminates the surface of the workpiece, and a marker 105 that is provided on the mounting plate 102 and marks defective portions on the workpiece. The robot arm 100 may be provided with an ionizer for blowing away contaminants and the like that are fixed to a predetermined position.

[0016] Fig. 5 is a plan view and a side view of the robot arm 100. The left diagram of Fig. 5 is a plan view of the robot arm 100, and the right diagram of Fig. 5 is a side view of the robot arm 100. As shown in the plan view of the robot arm 100, the robot arm 100 includes an arm body 101 and a mounting plate 102 provided at the tip of the robot arm 100. Note that only the arm body 101 may be referred to as the robot arm.

[0017] The imaging unit 103 is provided on the mounting plate 102 so as to be movable, for example, by a stepping motor on an arc centered on the workpiece imaging position 120. In Fig. 5, the imaging unit 103 is provided so as to be movable within a range on an arc of 48°, but the range of movement is not limited to this.

[0018] Similarly, the illumination unit 104 is provided on the mounting plate 102 so as to be movable, for example, by a stepping motor, on an arc centered on the workpiece imaging position 120. In Fig. 5, the illumination unit 104 is provided so as to be movable within a range on an arc of 48°, but the range of movement is not limited to this.

[0019] In this way, even if the robot arm 100 remains fixed, the angle of illumination for the same position on the work can be changed arbitrarily by moving the imaging unit 103 and the illumination unit 104 to any position on an arc centered on the imaging position 120 of the work. Therefore, by changing the positions of the imaging unit 103 and the illumination unit 104, the contrast difference of the defective part of the work can be emphasized, making it possible to easily detect the defective part.

[0020] 5, a marker 105 is attached to the mounting plate 102, and the marker 105 comes forward by tilting the mounting plate 102. In this state, the inspection device 1 can mark a defective portion found on the workpiece by moving the robot arm 100 while referring to the position of the defective portion detected from the image captured by the imaging unit 103.

[0021] Fig. 6 is a diagram showing an example of the appearance of the dolly 300. The dolly 300 is roughly divided into a mounting table 301 for mounting a workpiece thereon, and a fixing part 302 for fixing the mounting table 301. Fig. 6 shows a case where a flange provided with an O-ring groove is mounted on the mounting table 301 as an example of the workpiece 400.

[0022] Fixing portion 302 is a portion for fixing mounting table 301, and by rotating lock handle 303, it is possible to select whether mounting table 301 is in a fixed state or in a reversible state. Hereinafter, the lock handle will be simply referred to as the handle.

[0023] 7 is a diagram showing an example of the appearance of the fixed part 302 of the cart 300, showing that the mounting table 301 of the cart 300 is in a state where it can be inverted. The fixed part 302 is provided with a handle 303, and when the handle 303 is in the state shown in FIG. 7, the fixing pin that fixes the mounting table 301 is removed, making it possible to rotate the mounting table 301 and invert the workpiece 400.

[0024] Fig. 8 is a diagram showing an example of the appearance of fixed part 302 of cart 300, showing that mounting base 301 of cart 300 is in a fixed state. Fixed part 302 is provided with handle 303, and when handle 303 is in the state shown in Fig. 8, mounting base 301 is fixed by a fixing pin.

[0025] <Functional configuration of inspection device 1> 9 is a block diagram showing an example of a functional configuration of an inspection device 1 according to an embodiment of the present invention. The inspection device 1 includes a robot arm 100, an information processing device 200, and a dolly 300.

[0026] The robot arm 100 includes an imaging unit 103, an illumination unit 104, an imaging unit drive unit 110, an illumination unit drive unit 111, and a robot arm drive unit 112. The imaging unit 103 is configured with a CCD (Charge Coupled Device) camera or the like capable of capturing two-dimensional images, and captures an image of the surface of the workpiece 400. The video captured by the imaging unit 103 is output to the information processing device 200.

[0027] The imaging unit driving unit 110 is configured with a stepping motor or the like, and moves the imaging unit 103 on the mounting plate 102 in response to an instruction from the information processing device 200. As shown in Fig. 5, the imaging unit driving unit 110 is provided on the mounting plate 102 so as to be movable on an arc centered on an imaging position 120 of the work. The imaging unit driving unit 110 can move the imaging unit 103 within a range of a 48° arc, as shown in Fig. 5, in response to an instruction from the information processing device 200.

[0028] The illumination unit 104 is configured with a white backlight illumination, an LED (Light Emitting Diode) illumination, or the like, and is provided so as to be able to irradiate the inspection range of the workpiece 400 with parallel light over a wide range.

[0029] The illumination unit driving unit 111 is configured with a stepping motor or the like, and moves the illumination unit 104 on the mounting plate 102 in response to an instruction from the information processing device 200. As shown in Fig. 5, the illumination unit driving unit 111 is provided on the mounting plate 102 so as to be movable on an arc centered on the imaging position 120 of the work. The illumination unit driving unit 111 can move the illumination unit 104 within a range of a 48° arc, as shown in Fig. 5, in response to an instruction from the information processing device 200.

[0030] The information processing device 200 tilts the imaging unit 103 and the illumination unit 104 in a V-shape with respect to the workpiece 400, so that the imaging unit 103 can image the difference in reflected light between a normal surface and an abnormal surface (defective portion) of the groove surface of the workpiece 400, thereby enabling the defective portion to be detected. The information processing device 200 moves the imaging unit 103 and the illumination unit 104 along the groove curved surface so that the contrast difference between the normal surface and the abnormal surface (defective portion) of the groove surface becomes large (for example, so that the gradation difference becomes 30 to 40).

[0031] The robot arm driving unit 112 is constituted by a linear driving device or the like, and can move the attachment plate 102 to any position and direction according to instructions from the information processing device 200, as described above.

[0032] The information processing device 200 includes an image input unit 201, an inspection unit 202, a control unit 203, and an operation unit 204. The image input unit 201 inputs an image captured by the imaging unit 103, and outputs the image to the inspection unit 202.

[0033] The inspection unit 202 obtains the image from the image input unit 201 and performs general image processing to detect defective portions on the workpiece 400. As described below, when the void diameter of the defective portion is 0.16 mm or more, the inspection unit 202 judges the defective portion to be a complete defect as Complete NG, and when the void diameter of the defective portion is 0.16 mm or less, the inspection unit 202 judges the defective portion to be an ambiguous defect as Fuzzy NG.

[0034] The control unit 203 controls the imaging unit driving unit 110, the lighting unit driving unit 111 and the robot arm driving unit 112 to move the mounting plate 102, the imaging unit 103 and the lighting unit 104 and sequentially capture images of the groove curved surface of the workpiece 400.

[0035] The control unit 203 may also control the movement of the imaging unit 103 and the illumination unit 104 depending on the type of the workpiece 400. For example, since the contrast difference between a normal surface and an abnormal surface (defective portion) of the groove surface differs between a V-groove and a U-groove O-ring groove, the positions of the imaging unit 103 and the illumination unit 104 may be changed depending on the type of the workpiece 400.

[0036] The operation unit 204 is configured with a touch panel or the like, and various operations are accepted when the worker touches the panel. The operation unit 204 notifies the control unit 203 of various operation instructions input by the worker.

[0037] <Processing procedure of inspection device 1> 10 is a flowchart for explaining the processing procedure of the inspection device according to the embodiment of the present invention. Note that the automatic mode is a mode in which the workpiece 400 is inspected without the intervention of an operator. Also, the semi-automatic mode is a mode in which the workpiece 400 is inspected with the intervention of an operator.

[0038] First, an operator carries the dolly 300 in front of the robot stand (in front of the robot arm 100 shown in FIG. 3), opens a cover door for covering the inspection device 1, and positions the dolly 300 (S1). Next, the operator lifts up the dolly 300 and closes the cover door (S2).

[0039] Next, the worker operates the operation unit 204 provided in the information processing device 200 to set the type of the workpiece 400, perform alignment correction, specify the inspection location, select automatically or semi-automatically, and so on (S3).

[0040] Next, the inspection device 1 performs positioning correction (x, y directions) of the carriage 300 (S4), and performs positioning correction (z direction) of the workpiece 400 (S5), thereby performing alignment correction. Note that this alignment correction is not particularly related to the present invention, so a detailed description will not be provided.

[0041] Next, the control unit 203 determines whether the automatic mode or the semi-automatic mode is selected by the operator (S6). When the automatic mode is selected by the operator, the control unit 203 controls the imaging unit driving unit 110, the lighting unit driving unit 111, and the robot arm driving unit 112 to move the mounting plate 102, the imaging unit 103, and the lighting unit 104, and sequentially acquires images of the groove curved surface of the workpiece 400. Then, the inspection unit 202 performs image analysis on the images captured by the imaging unit 103 to detect Complete NG, in which the void diameter of the defective portion is 0.16 mm or more, and Fuzzy NG, in which the void diameter of the defective portion is 0.16 mm or less (S7). When Complete NG is detected, the defective portion is marked using the marker 105. Note that this process of S7 continues even if Complete NG or Fuzzy NG is detected. Then, when all the inspection points specified by the operator have been inspected, the process of step S7 ends.

[0042] Furthermore, if the semi-automatic mode is selected by the operator in step S6, the control unit 203 performs the inspection in the semi-automatic mode (S8), and the process proceeds to step S9. The process of step S8 will be described in detail later.

[0043] Next, the worker opens the cover door (S9) and inverts the workpiece 400 (S10). Then, the worker closes the cover door (S11) and operates the operation unit 204 provided in the information processing device 200 to set the type of the workpiece 400, correct alignment, specify the inspection location, select automatically or semi-automatically, and the like (S12).

[0044] Next, the inspection device 1 performs positioning correction (x and y directions) of the carriage 300 (S13), performs positioning correction (z direction) of the workpiece 400 (S14), and performs alignment correction.

[0045] Next, the control unit 203 determines whether the automatic mode or the semi-automatic mode has been selected by the operator (S15). If the automatic mode has been selected by the operator, the same process as in step S7 is performed (S16). If the semi-automatic mode has been selected by the operator, the same process as in step S8 is performed (S17).

[0046] Next, the worker opens the cover door and lifts down the dolly 300 (S18). Then, the worker closes the cover door and removes the dolly 300 from in front of the robot stand (S19), completing the process.

[0047] Fig. 11 is a flowchart for explaining the details of the process of the inspection in the semi-automatic mode (S8, S17) shown in Fig. 10. First, the operator operates the operation unit 204 provided in the information processing device 200 to press a start button indicating the start of the inspection in the semi-automatic mode (S81), and the information processing device 200 starts the inspection in the semi-automatic mode (S82).

[0048] The control unit 203 controls the imaging unit driving unit 110, the lighting unit driving unit 111, and the robot arm driving unit 112 to move the mounting plate 102, the imaging unit 103, and the lighting unit 104, and sequentially acquires images of the curved groove surface of the workpiece 400. Then, the inspection unit 202 performs image analysis on the images captured by the imaging unit 103 to detect Complete NG or Fuzzy NG.

[0049] If neither Complete NG nor Fuzzy NG is detected (S83, Yes), the operator presses the end confirmation button on the operation unit 204 provided in the information processing device 200 (S87), ends the inspection, and the process proceeds to step S9.

[0050] Moreover, if a Complete NG is detected (Yes in S84), the control unit 203 notifies the operator that a Complete NG has been detected (S88), and uses the marker 105 to mark the defective portion (S89).

[0051] When the operator presses the inspection restart button, the inspection is restarted (S90). When the inspection is completed, the operator presses the end confirmation button (S87), the inspection is terminated, and the process proceeds to step S9.

[0052] Furthermore, if Fuzzy NG is detected (S85, Yes), the control unit 203 notifies the worker that Fuzzy NG has been detected (S100), and displays a worker confirmation alarm on the operation unit 204 provided in the information processing device 200 (S101). Also, the alarm may be notified to the worker by sound.

[0053] Next, the worker opens the cover door and checks the workpiece 400 (S102). Then, the worker closes the cover door and operates the operation unit 204 provided in the information processing device 200 to instruct whether or not to mark the defective portion (103).

[0054] When marking of the defective portion is to be performed (S103, performed), the operator cancels the alarm for operator confirmation (S104) and the inspection is resumed (S105). Then, the control unit 203 performs marking of the defective portion using the marker 105 (S106), the imaging unit 103 continues imaging (S107), and when the inspection is completed (S108), the process proceeds to step S87.

[0055] If marking of the defective portion is not to be performed (S103, not performed), the operator cancels the alarm for operator confirmation (S109), the inspection is resumed (S110), and the process proceeds to step S107.

[0056] If both Complete NG and Fuzzy NG are detected (S86, Yes), the control unit 203 notifies the operator that Complete NG has been detected (S120), and performs marking on the defective portion using the marker 105 (S121). Then, when the operator presses the inspection resume button, the inspection is resumed (S122), and the process proceeds to step S100.

[0057] <Effects of Inspection Device 1> As described above, according to the inspection device 1 of this embodiment, the imaging unit 103 and the illumination unit 104 are provided on the mounting plate 102 so as to be movable on an arc centered on the imaging position of the workpiece 400. Therefore, by the control unit 203 moving the imaging unit 103 and the illumination unit 104, it is possible to increase the contrast difference between the normal surface and the abnormal surface (defective portion) of the groove surface, and the inspection unit 202 can easily detect the defective portion of the workpiece.

[0058] In addition, the control unit 203 controls the movement of the imaging unit 103 and the illumination unit 104 depending on the type of workpiece 400, thereby making it possible to increase the contrast difference between the normal surface and the abnormal surface (defective portion) of the groove surface.

[0059] Moreover, the inspection device 1 further includes a marker that is provided on the mounting plate 102 and is used to mark defective portions on the workpiece 400, so that the worker can easily identify the defective portions.

[0060] In addition, the platform 301 of the cart 300 is provided on the cart 300 so as to be reversible so that the back surface of the workpiece 400 can be imaged by the imaging unit 103. Therefore, the worker can easily turn over even a heavy workpiece, which reduces the workload.

[0061] [Software implementation example] The control block of the inspection device 1 (particularly the inspection unit 202 and the control unit 203) may be realized by a logic circuit (hardware) formed in an integrated circuit (IC chip) or the like, or may be realized by software.

[0062] In the latter case, the inspection device 1 includes a computer that executes instructions of a program, which is software that realizes each function. The computer includes, for example, one or more processors, and a computer-readable recording medium that stores the program. The object of the present invention is achieved by the processor reading the program from the recording medium and executing it in the computer. The processor may be, for example, a CPU (Central Processing Unit). The recording medium may be a "non-transient tangible medium", such as a ROM (Read Only Memory), a tape, a disk, a card, a semiconductor memory, a programmable logic circuit, or the like. The device may further include a RAM (Random Access Memory) that expands the program. The program may be supplied to the computer via any transmission medium (such as a communication network or a broadcast wave) that can transmit the program. Note that one aspect of the present invention may also be realized in the form of a data signal embedded in a carrier wave, in which the program is embodied by electronic transmission.

[0063] 〔summary〕 The inspection device according to aspect 1 of the present invention comprises a robot arm capable of changing the position and direction of a mounting plate provided at the tip, an imaging unit movably provided along the mounting plate for capturing an image of a workpiece, an illumination unit movably provided along the mounting plate for illuminating the workpiece surface, and an inspection unit for inspecting the workpiece surface based on the image captured by the imaging unit.

[0064] The inspection device according to a second aspect of the present invention is the above-mentioned first aspect, wherein the imaging section is configured to be movable on an arc centered on the imaging position of the work.

[0065] The inspection device according to aspect 3 of the present invention is based on aspect 1 or 2 above, and is configured such that the illumination unit is movable on an arc centered on the position where the work is imaged by the imaging unit.

[0066] An inspection apparatus according to aspect 4 of the present invention is, in any of aspects 1 to 3 above, further comprising a control unit that controls movement of the imaging unit and the lighting unit, and the control unit controls the movement of the imaging unit and the lighting unit according to the type of the work.

[0067] A fifth aspect of the present invention is directed to an inspection device in any one of the first to fourth aspects, further comprising a marker provided on the mounting plate for marking a defective portion on the workpiece.

[0068] The inspection apparatus according to aspect 6 of the present invention is, in any one of aspects 1 to 5 above, further comprising a cart having a mounting table on which the workpiece is placed and which is transported in and out of the inspection apparatus, the mounting table being reversibly mounted on the cart so that the back side of the workpiece can be imaged by the imaging unit.

[0069] [Additional Notes] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. [Explanation of symbols]

[0070] 1. Inspection equipment 100 Robot Arm 101 Arm body 102 Mounting plate 103 Imaging unit 104 Lighting Department 105 Marker 110 Imaging unit drive unit 111 Lighting unit drive unit 112 Robot arm drive unit 201 Video input section 202 Inspection Department 203 Control Unit 204 Operation section 300 Carts 301 Placement table 302 Fixed part 303 Handle 400 Work

Claims

1. A robot arm capable of changing the position and direction of a mounting plate provided at the tip thereof; An imaging unit that is movably provided along the mounting plate and captures an image of the workpiece; An illumination unit that is movable along the mounting plate and illuminates the work surface; An inspection device comprising: an inspection unit that inspects the surface of the workpiece based on the image captured by the imaging unit.

2. The imaging unit is configured to be movable on an arc centered on the imaging position of the workpiece.

2. The inspection device according to claim 1.

3. The illumination unit is configured to be movable on an arc centered on the imaging position of the work by the imaging unit.

3. The inspection device according to claim 1 or 2.

4. The inspection apparatus further includes a control unit that controls movement of the imaging unit and the illumination unit, The control unit controls the movement of the imaging unit and the illumination unit according to the type of the workpiece.

4. The inspection device according to claim 3.

5. The inspection device further includes a marker provided on the mounting plate for marking a defective portion on the workpiece.

2. The inspection device according to claim 1.

6. The inspection apparatus further includes a carriage having a platform on which the workpiece is placed and which is carried in and out of the inspection apparatus; The mounting table is provided on the cart in a reversible manner so that the back surface of the workpiece can be imaged by the imaging unit.

2. The inspection device according to claim 1.

Images