JP2004109038A - Inspection method and apparatus for breaking of wire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently and reliably inspect the disconnection of wires and to automate inspection. <P>SOLUTION: The inspection apparatus for the disconnection of wires is provided with a heat ray camera 7 for photographing a glass sheet 1 in which a conductor pattern is formed in a glass surface; a transfer robot 2 for moving the glass sheet by, for example, adhering to the glass surface by suction on the opposite side of the conductor pattern; a clamp device 3 for holding the glass sheet 1 at an inspection location; a feeder system 4 for providing a prescribed inspection voltage for the the conductor pattern of the glass sheet 1; and a CPU 6 for determining the breaking of wires from a heat image photographed by the heat ray camera 7. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a disconnection inspection method and apparatus for a glass plate on which a conductor pattern is formed.
[0002]
[Prior art]
A defrosting heater is patterned on a rear window of an automobile by printing a conductive material such as silver paste. Such a conductor pattern such as a heater has a grid shape in which usually a plurality of horizontal conductor lines (element wires) are connected by vertical electrode lines (bus bars) at both left and right ends. The window glass plate for automobiles having such a conductor pattern is subjected to disconnection inspection during the manufacturing process.
[0003]
Conventionally, a method of rolling a metal roller on a glass surface has been used as this disconnection inspection. In this method, two metal rollers are rolled on a conductor pattern, the continuity of pattern wires is inspected by an inspection circuit connected to the metal roller, and the number of the wires is measured to determine the disconnection.
[0004]
[Problems to be solved by the invention]
However, in the inspection method for rolling the metal roller, the electrical contact state between the metal roller and the conductor pattern is easily affected by dust on the glass surface, and the product is reliable for inspection and quality. There is a risk of reducing the performance. In addition, since the metal roller is rolled on the glass surface while reliably conducting electrical conduction manually, it is impossible to automate, requiring a lot of inspection time and working efficiency.
[0005]
The present invention has been made in consideration of the above-described prior art, and an object of the present invention is to provide a disconnection inspection method and apparatus capable of inspecting disconnection efficiently and reliably and capable of automating the inspection.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the present invention is a disconnection inspection method for determining a disconnection of a conductor pattern from a thermal image by photographing a glass plate having a conductor pattern formed on a glass surface with a heat ray camera. The disconnection is characterized in that a disconnection is determined by taking a photograph of the conductor pattern forming surface side with a wavelength of 14 μm as a measurement wavelength of the heat ray camera and comparing the thermal image with a thermal image of a reference pattern registered in advance. Provide inspection methods.
[0007]
According to this configuration, the glass plate is photographed from the front surface side where the conductive pattern of the glass plate is formed using a heat ray camera at a predetermined wavelength (8 to 14 μm) that does not transmit a thermal image on the back surface side of the glass plate. Thus, a thermal image of the conductor pattern can be obtained without being affected by the thermal effect of the transfer robot or the like on the back side of the glass plate. By comparing this thermal image with a thermal image of a normal conductor pattern, the disconnection state can be accurately determined.
[0008]
In the present invention, as an inspection apparatus for carrying out the disconnection inspection method, a heat ray camera for photographing a glass plate having a conductor pattern formed on the glass surface, a transfer robot for moving the glass plate, and the glass plate at the inspection position. A disconnection inspection apparatus comprising: a holding clamp apparatus; a power supply apparatus that applies a predetermined inspection voltage to a conductor pattern of a glass plate; and a control apparatus that determines disconnection from a thermal image captured by the heat ray camera. I will provide a.
[0009]
According to this configuration, for example, the back side of the glass plate (the side opposite to the surface on which the conductor pattern is formed) is sucked by the transfer robot and transferred to the imaging position, where the glass plate is mounted and supported on the support frame, for example. Or by holding a clamp device such as an air cylinder, and applying a predetermined voltage according to the inspection conditions from the power feeding device to the conductor pattern in the held state, heating the conductor pattern, and setting the temperature difference from the glass plate to a predetermined temperature As described above, the heated conductor pattern is photographed with a hot-wire camera, and the thermal image is sent to a control device such as a CPU to determine the disconnection state. As a result, a highly reliable disconnection inspection can be performed, and the inspection can be automated, thereby shortening the inspection time.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a block diagram of a disconnection inspection apparatus according to an embodiment of the present invention.
A conductor pattern (see FIG. 2) is formed on the indoor surface side (concave surface side) of the glass plate 1 constituting the rear window of the automobile. The glass plate 1 is sucked at several positions on the back side of the glass plate by the arm of the vacuum suction type transfer robot 2 and is carried to the inspection position, and is mounted at a predetermined position on a support frame (not shown). The support frame is provided with a clamp device 3 for fixing and holding the glass plate 1 and a power feeding device 4 for energizing the conductor pattern of the glass plate 1. These transfer robot 2, clamping device 3, and power feeding device 4 are connected to a control device (CPU) 6 together with a power supply device 5. Further, a heat ray camera 7 for photographing the conductor pattern forming surface side of the glass plate 1 and a storage device 6 a for storing and holding various control programs, reference image data described later, and the like are connected to the CPU 6. The CPU 6 is accommodated in a personal computer main body (not shown), and a monitor 8 and an input keyboard 9 are connected thereto.
[0011]
The CPU 6 drives the transport robot 2 and the clamp device 3 according to a predetermined program to transport and fix the glass plate 1 to a predetermined inspection position. The power supply device 4 applies a predetermined voltage from the power supply device 5. The glass plate 1 is photographed with the hot-wire camera 7 after being supplied to the conductor pattern and raising the temperature. The CPU 6 displays the captured thermal image on the monitor 8 and determines the disconnection state of the thermal image by comparison with a reference pattern registered in advance. Inspection conditions such as inspection voltage applied to the conductor pattern and energization time can be input from the keyboard 9. Such a CPU 6 controls the sequence of the inspection process in accordance with the program, and the disconnection inspection can be automated.
[0012]
The measurement wavelength by the heat ray camera 7 is 8 to 14 μm. This wavelength band is out of the frequency band where glass can be measured, and the measured image does not transmit the image on the back side of the glass plate, and imaging data only on the front side can be obtained. Therefore, for example, even when a robot hand is attracted to the back side of the glass plate or when an operator is present, these back side images cannot be captured by the heat ray camera and sent to the CPU. Does not appear in the thermal image. In this way, by setting the specific wavelength that does not transmit the glass plate as the measurement wavelength, a thermal image of only the conductive pattern on the front side of the glass plate can be obtained without being affected by the state of the back side of the glass plate to be photographed. Disconnection can be judged.
[0013]
FIG. 2 shows an example of a thermal image of a conductor pattern.
The example of (A) is an example in which a conductor pattern 12 including a plurality of horizontal lines (element wires) 10 and vertical lines (bus bars) 11 serving as common electrodes for connecting them at both left and right ends is formed on the surface of the glass plate 1. is there.
[0014]
The example of (B) is an example of the conductor pattern 14 in which three vertical lines 13 are formed in the middle of the horizontal line 10 and these vertical lines 13 are used as an antenna for radio reception. 25 is another radio receiving antenna, and 26 is an antenna for a mobile phone or a TV.
[0015]
The example of (C) is a thermal image of a pattern with a disconnection. This example is an example in the case where a part of the conductor pattern 12 in FIG. If a part of the strand 10 is disconnected, the strand 10 is not energized, and the entire strand does not generate heat. For this reason, the strand does not appear in the thermal image (broken line in the figure). Therefore, by comparing the thermal image of (A) with the thermal image of (C) as a reference image, a broken wire (broken line) can be clearly identified.
[0016]
The example of (D) shows an example in which a part (broken line) of the strand of the conductor pattern 14 having the three vertical lines 13 shown in (B) is broken. Since the wire portion between the vertical lines 13 on both sides of the disconnected portion is not energized, the wire in that portion does not generate heat. For this reason, the strand of that part does not appear in the thermal image (broken line in the figure). Therefore, by comparing the thermal image of (B) with the thermal image of (D) using the thermal image of (B) as a reference image, the broken strand (broken line) can be clearly identified.
[0017]
FIG. 3 is a detailed view showing an example of a clamp portion of the glass plate of the disconnection inspection apparatus according to the present invention.
As described above, the glass plate 1 is sucked on the back side (upper side in the drawing) by a robot (not shown) and is transported to the inspection position. A rotary actuator 15 is provided at the inspection position. The rotary actuator 15 rotates the clamp arm 16 connected thereto as indicated by an arrow A. A presser cylinder 17 is provided at the tip of the clamp arm 16. In this presser cylinder 17, the rod 17 a reciprocates as indicated by an arrow B to press the back side of the glass plate 1. A cushioning material 18 such as neoprene rubber is provided at the tip of the rod 17a.
[0018]
A power supply cylinder 19 is provided on the lower surface side (conductor pattern forming surface side) of the glass plate 1 so as to face the presser cylinder 17. In the power supply cylinder 19, the rod 19 a reciprocates as indicated by an arrow C to move the power supply pin 20 at the tip of the rod up and down. The power supply pin 20 is connected to a power supply device (not shown) such as a battery via a cable 21. The power feed pin 20 is fixed to the tip of the rod 19a through an insulating material 22 such as a bake plate.
[0019]
A base cylinder 24 is provided below the power supply cylinder 19. The base cylinder 24 has a support plate 23 at the tip of the rod 24 a, and the power supply cylinder 19 is fixed to the support plate 23. As the rod 24a of the base cylinder 24 reciprocates as indicated by an arrow D, the entire power supply cylinder 19 moves up and down.
[0020]
When setting the glass plate 1 to be inspected, the rotary actuator 15 is driven to move the clamp arm 16 to the retracted position indicated by the one-dot chain line in the figure. In this state, the glass plate 1 is carried in and the glass plate 1 is mounted on a support frame (not shown). Next, the power supply cylinder 19 and the base cylinder 24 are driven, the impact is reduced by a two-stage cylinder operation, and the power supply pin 20 is brought into contact with the conductor pattern of the glass plate 1.
[0021]
Next, the rotary actuator 15 is driven to move the clamp arm 16 from the retracted position to the inspection position indicated by the solid line in the figure. In this state, the presser cylinder 17 is driven to press and hold the glass plate 1 on a support frame (not shown) via the cushion material 18. In this state, a predetermined voltage is applied to the conductor pattern through the power supply pin 20 for a predetermined time to cause the conductor pattern to generate heat. In a state where the conductor pattern is heated to a predetermined temperature or higher, the conductor pattern is photographed with a hot wire camera and a disconnection inspection is performed. When the inspection is completed, the rod 17a of the presser cylinder 17 is retracted, and the rotary actuator 15 is driven again to move the clamp arm 16 to the retracted position (dashed line). The glass plate 1 that has been inspected in this state is sucked out by the suction pad of the robot.
[0022]
FIG. 4 is a flowchart of the disconnection inspection method according to the present invention. The operation of each step is as follows.
Step S1:
A good glass plate without disconnection is set in an inspection state, and this is used as a reference glass plate and photographed with a heat ray camera to obtain a thermal image.
[0023]
Step S2:
The thermal image data of the reference glass plate is registered in the CPU memory as a reference pattern. When the reference pattern data is acquired in advance or can be obtained from the design data, the reference pattern data may be input from the keyboard 9 (FIG. 1).
[0024]
Step S3:
The glass plate to be inspected is conveyed by a robot and set at the inspection position as described above (FIG. 3). A predetermined inspection voltage is applied to the conductive pattern of the set glass plate for a predetermined time. The inspection voltage and energization time are set in advance so that the difference between the temperature of the glass plate and the temperature of the conductor pattern is equal to or higher than a predetermined temperature that can be identified by the hot-wire camera. Alternatively, these inspection conditions may be input from a keyboard.
[0025]
Step S4:
The glass plate is photographed with a hot-wire camera while the conductor pattern is heated, and the photographed thermal image data is sent to the CPU.
Step S5:
The thermal image data sent to the CPU is compared with the registered reference pattern data (step S2) to determine the presence or absence of disconnection (see FIG. 2).
[0026]
Step S6:
The current value when a predetermined voltage is applied to the conductor pattern is measured, and the resistance is calculated in the CPU. If the resistance value is larger or smaller than the allowable value of the normal conductor pattern, it is determined that the pattern is defective due to a pattern width defect or the like.
[0027]
【The invention's effect】
As described above, in the present invention, from the front surface side where the conductive pattern of the glass plate is formed, this glass plate is photographed with a heat wave camera at a predetermined wavelength that does not transmit the thermal image on the back surface side of the glass plate. Thus, a thermal image of the conductor pattern can be obtained without being affected by the thermal effect of the transfer robot or the like on the back side of the glass plate. By comparing this thermal image with a thermal image of a normal conductor pattern, the disconnection state can be accurately determined.
[0028]
In the present invention, the back side of the glass plate is sucked by the transfer robot and transferred to the imaging position, where the glass plate is mounted and supported on a support frame or held by a clamp device such as an air cylinder. In this state, a predetermined voltage corresponding to the inspection condition is applied to the conductor pattern from the power feeding device to heat the conductor pattern, and the temperature difference from the glass plate is set to a predetermined temperature or higher. An image is taken and the thermal image is sent to the CPU to determine the disconnection state. As a result, a disconnection inspection with high reliability can be performed, and the inspection can be automated, thereby shortening the inspection time.
[Brief description of the drawings]
FIG. 1 is a block diagram of a disconnection inspection apparatus according to an embodiment of the present invention.
FIG. 2 is an explanatory view of a shape example of a conductor pattern.
FIG. 3 is a main part configuration diagram of a disconnection inspection apparatus according to the present invention.
FIG. 4 is a flowchart of a disconnection inspection method according to the present invention.
[Explanation of symbols]
1: glass plate, 2: transport robot, 3: clamping device, 4: power feeding device,
5: power supply device, 6: CPU, 7: heat ray camera, 8: monitor, 9: keyboard,
10: Horizontal line (elementary wire), 11: Vertical line (bus bar), 12: Conductor pattern,
13: Vertical line, 14: Conductor pattern, 15: Rotary actuator,
16: Clamp arm, 17: Presser cylinder, 17a: Rod,
18: cushion material, 19: power supply cylinder, 19a: rod, 20: power supply pin,
21: Cable, 22: Insulating material, 23: Support plate, 24: Base cylinder,
24a: Rod, 25: Radio receiving antenna,
26: Mobile phone or TV receiving antenna.

Claims (2)

A disconnection inspection method for determining the disconnection of the conductor pattern from the thermal image by photographing a glass plate having a conductor pattern formed on the glass surface with a heat ray camera,
Taking a wavelength of 8 to 14 μm as a measurement wavelength of the heat ray camera, photographing from the surface on which the conductor pattern is formed, and determining the disconnection by comparing the thermal image with a thermal image of a reference pattern registered in advance. Disconnection inspection method. A heat ray camera for photographing a glass plate having a conductor pattern formed on the glass surface;
A transfer robot that moves the glass plate;
A clamping device for holding the glass plate in the inspection position;
A power feeding device for applying a predetermined inspection voltage to the conductor pattern of the glass plate;
A disconnection inspection apparatus comprising: a control device that determines disconnection from a thermal image captured by the heat ray camera.

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