A device for detecting foreign objects on the surface of a glass substrate

Abstract

The present invention discloses a device for detecting foreign objects on the surface of a glass substrate, comprising: a bracket, which is arranged perpendicular to the conveying direction of the glass substrate and is located below the glass substrate; a plurality of guide rails, which are all arranged on the bracket along the conveying direction of the glass substrate; a plurality of sliding parts, which are arranged side by side perpendicular to the conveying direction of the glass substrate, each of the plurality of sliding parts includes a stop rod and sliders fixedly connected to both ends of the stop rod, the sliders are slidably connected with the slide rails so that the stop rod can slide along the conveying direction of the glass substrate, and there is a gap between the top surface of the stop rod and the surface of the glass substrate; and a detection unit, which is used for detecting the displacement of the stop rod. In the device of the present invention, the slidable stop rod can not only remove foreign objects with relatively small adhesion, but also detect glass substrates with foreign objects that cannot be removed.

Description

Technical Field

[0001] The present invention relates to the technical field of liquid crystal display panel modules. More specifically, it relates to a device for detecting foreign objects on the surface of a flat glass substrate. Background Art

[0002] With the high-end development of electronic products, the overall quality requirements for the initial TFT-LCD glass substrates are more stringent. The glass substrate for flat panel displays is a product with extremely high requirements for surface cleanliness. When the glass substrate is cut, ground, cleaned, and transported on the transmission line, it will be subject to varying degrees of secondary contamination. The glass substrate includes two surfaces, a front surface and a back surface. Currently, in the production process, only the front surface of the glass substrate, that is, the working surface, is subjected to particle detection, while the back surface of the glass substrate is usually not subjected to particle detection. Moreover, since the back surface of the glass substrate contacts the transmission line, the device for detecting particles on the front surface of the glass substrate is not applicable to the detection of the back surface of the glass substrate. Summary of the Invention

[0003] An object of the present invention is to provide a device for detecting foreign objects on the surface of a glass substrate, which can detect particles on the back surface of the glass substrate.

[0004] According to one aspect of the present invention, there is provided a device for detecting foreign objects on the surface of a glass substrate, comprising:

[0005] A bracket, the bracket is arranged perpendicular to the conveying direction of the glass substrate and is located below the glass substrate;

[0006] A plurality of guide rails, the guide rails are all arranged on the bracket along the conveying direction of the glass substrate;

[0007] A plurality of sliding parts, the plurality of sliding parts are arranged side by side perpendicular to the conveying direction of the glass substrate. Each sliding part includes a stop bar and sliders fixedly connected to both ends of the stop bar. The sliders are slidably connected with the slide rails so that the stop bar can slide along the conveying direction of the glass substrate. There is a gap between the top surface of the stop bar and the surface of the glass substrate; and

[0008] A detection unit, the detection unit is used to detect the displacement of the stop bar.

[0009] Preferably, the two ends of the stop bars of the plurality of sliding parts are close to each other, and the two ends of the stop bars located on both sides of the glass substrate are respectively located outside the glass substrate.

[0010] Preferably, the bracket is arranged as a rectangular frame, and the plurality of guide rails are fixedly combined on the rectangular frame.

[0011] Preferably, the conveying mechanism for conveying the glass substrate includes a plurality of rows of rollers arranged in parallel, and the guide rails are respectively arranged on both sides of one row of rollers, so that one roller corresponds to one of the stop rods.

[0012] Preferably, the detection unit includes a detection circuit, a plurality of resistance sheets fixedly bonded to the surface of the guide rail, and a plurality of sliding sheets with one end connected to the slider and the other end in contact with the resistance sheet. The detection circuit detects the displacement of the stop rod by detecting the change in the resistance value between the resistance sheet and the sliding sheet.

[0013] Preferably, the detection unit includes a detection circuit, and a plurality of light sources and light receivers respectively located on both sides of the slider. When the slider moves, the light received by the light receiver changes, and the detection circuit detects the displacement of the stop rod by detecting the light change signal of the light receiver.

[0014] Preferably, the detection unit is also connected to the control unit of the conveying mechanism for conveying the glass substrate. When the detection unit detects the movement of the stop rod, the control unit can stop the operation of the conveying mechanism according to the signal sent by the detection unit.

[0015] Preferably, the bracket includes a plurality of cross bars connected to the frame of the conveying device for conveying the glass substrate, and a plurality of vertical bars connected to the cross bars. The cross bars are arranged along the conveying direction of the glass substrate, and the guide rails are arranged at the top of the vertical bars.

[0016] Preferably, the gap between the top surface of the stop rod and the surface of the glass substrate ranges from 150 to 300 microns.

[0017] Preferably, the stop rod is made of a hard metal material, and the cross-sectional shape of the stop rod is set as a rectangle.

[0018] The beneficial effects of the present invention are as follows:

[0019] The device for detecting foreign objects on the surface of a glass substrate according to the present invention can remove foreign objects with relatively small adhesion by using the stop rod to block the foreign objects attached to the back surface of the glass substrate. For foreign objects with relatively large adhesion, the foreign objects push the stop rod to move, and the detection unit can detect that there are foreign objects attached to the surface of the glass substrate by detecting the movement of the stop rod. In the device of the present invention, the slidable stop rod can not only remove foreign objects with relatively small adhesion, but also detect glass substrates with foreign objects that cannot be removed. Description of the Drawings

[0020] The following further describes in detail the specific embodiments of the present invention with reference to the accompanying drawings.

[0021] Figure 1 The top view of the device of the present invention is shown.

[0022] Figure 2 A side view of the device of the present invention is shown.

[0023] Figure 3 A schematic diagram of a partial structure of the device of the present invention is shown.

[0024] Figure 4 A schematic diagram of the structure of a detection unit of the device of the present invention is shown.

[0025] Figure 5 A partial side view of the device of the present invention is shown. Detailed implementation manners

[0026] To more clearly illustrate the present invention, the present invention will be further described below in conjunction with preferred embodiments and the accompanying drawings. Similar components in the drawings are denoted by the same reference numerals. Those skilled in the art should understand that the content specifically described below is illustrative rather than restrictive, and should not be used to limit the protection scope of the present invention.

[0027] During the production process of TFT-LCD, foreign object detection is only performed on the working surface of the glass substrate, that is, the front side of the glass substrate. However, foreign objects may also adhere to the back side of the glass substrate, and these foreign objects will also affect the characteristic data on the exposure machine table. Foreign objects on the back side of the glass substrate can not only cause product quality abnormalities but also damage the equipment. Currently, the detection devices usually perform foreign object detection through optical imaging and recognition. The structure of such detection devices is relatively complex and is not suitable for detecting foreign objects on the back side of the glass substrate. Currently, there is no dedicated equipment for detecting foreign objects on the back side of the glass substrate. However, foreign objects adhering to the back side of the glass substrate will cause the flat glass substrate to bulge. If such foreign objects with a relatively gentle bulge degree cannot be detected, it will have a certain impact on the product quality.

[0028] In view of the above problems, as Figure 1 and Figure 2 shown, an embodiment of the present invention provides a device for detecting foreign objects on the back side of a glass substrate, including a bracket 10, a guide rail 20, a sliding part 30, and a detection unit. The bracket 10 is arranged perpendicular to the conveying direction of the glass substrate, and the bracket 10 is located below the glass substrate 100. A plurality of guide rails 20 are provided, all of which are arranged on the bracket 10, and the guide rails 20 are arranged along the conveying direction of the glass substrate 100, that is, a plurality of guide rails 20 are fixedly arranged on the bracket 10 parallel to the conveying direction of the glass substrate 100. The guide rail 20 and the sliding part 30 are arranged on the bracket 10, both of which are located below the glass substrate 100. The detection unit can be arranged on the bracket and is used to detect the displacement of the sliding part 30.

[0029] The sliding parts 30 are provided in multiple numbers, and the multiple sliding parts 30 are arranged side by side in a direction perpendicular to the conveying direction of the glass substrate 100. Each sliding part 30 includes a stop bar 31 and sliders 32 fixedly connected to both ends of the stop bar 31. Each slider 32 corresponds to a guide rail 20. Through the sliding fit between the slider 32 and the guide rail 20, the stop bar 31 can slide along the conveying direction of the glass substrate 100, that is, each sliding part 30 can be displaced and slide independently. The sliding part 30 is located below the glass substrate 100, and there is a gap between the top surface of the stop bar 31 and the back surface of the glass substrate 100, that is, the stop bar 31 does not contact the surface of the glass substrate 100, and the stop bar 31 will not scratch the glass substrate 100. The detection unit is used to detect the movement of the stop bar 31, so as to detect foreign objects on the back surface of the glass substrate 100 through the movement of the stop bar 31.

[0030] Since the multiple sliding parts 30 are arranged in a direction perpendicular to the conveying direction of the glass substrate 100, the multiple stop bars 31 are arranged along the length direction of the glass substrate 100. Figure 1 In the direction shown, the conveying direction of the glass substrate 100 is the vertical direction, the multiple stop bars 31 are arranged in the horizontal direction, the multiple stop bars 31 penetrate the length direction of the glass substrate 100, and each stop bar 31 can be displaced and slide independently along the vertical direction.

[0031] When the glass substrate 100 moves on the transmission line, the bottom surface of the glass substrate 100 contacts the surface of the transmission line. Since the device of the present invention is located below the glass substrate 100, there is a certain gap between the bottom surface of the glass substrate 100, the back surface of the glass substrate 100 and the top surface of the stop bar 31. When the height of the foreign object attached to the back surface of the glass substrate 100 is greater than this gap, the foreign object can be blocked by the stop bar 31. If the adhesion between the foreign object and the glass substrate 100 is small, the foreign object can be scraped off the back surface of the glass substrate 100 by the stop bar 31. If the adhesion between the foreign object and the glass substrate 100 is relatively firm and the stop bar 31 cannot scrape off the foreign object from the back surface of the glass substrate 100, the foreign object will push the stop bar 31 to move along the conveying direction of the glass substrate 100. At this time, after the detection unit for detecting the displacement of the stop bar 31 detects the movement of the stop bar 31, it can send an alarm signal outward to enable the operator to check and process this glass substrate 100. That is to say, the stop bar of the device disclosed in the embodiment of the present invention can not only remove foreign objects with small adhesion, but also detect glass substrates with large adhesion of foreign objects that cannot be removed.

[0032] Specifically, the glass substrate 100 is horizontally placed on the transmission line. The transmission line is provided with a conveying device for carrying the glass substrate 100 and enabling the glass substrate 100 to move while maintaining a horizontal state. The stop bar 31 is parallel to the back surface of the glass substrate 100 and is located below it. There is a certain gap between the stop bar 31 and the back surface of the glass substrate 100. The glass substrate 100 continuously moves, so that the stop bar 31 sweeps across the entire back surface of the glass substrate 100. Since the extending direction of the guide rail 20 is parallel to the moving direction of the glass substrate 100, the sliders 32 at both ends of the stop bar 31 are slidably engaged with the guide rail 20, so that the guide rail 20 can slide along the moving direction of the glass substrate 100. That is to say, when a foreign object on the back surface of the glass substrate 100 comes into contact with the stop bar 31, if the adhesion force between the foreign object and the glass substrate 100 is greater than the force required to push the stop bar 31 to move, then as the glass substrate 100 moves, the stop bar 31 can be pushed to displace.

[0033] Since multiple stop bars 31 are provided in the present invention, the cross-section of the glass substrate 100 is jointly covered by the multiple stop bars 31. Since the length of a single stop bar 31 is short and its weight is light, it can be pushed by a foreign object. That is, a single foreign object will only push a single stop bar 31 and will not have a pushing effect on the other stop bars, avoiding the problem that the foreign object is neither scraped off by the stop bar 31 nor pushes the stop bar 31 to move, and improving the accuracy of the stop bar 31 in detecting foreign objects.

[0034] In an embodiment, the ends of adjacent stop bars 31 are close to each other, and a relatively small gap is provided between the ends of two adjacent stop bars 31 to prevent a large gap on the cross-section of the glass substrate 100 from not being covered by the stop bars 31, thereby preventing the stop bars 31 from being unable to remove or detect foreign objects on this gap, that is, preventing the phenomenon that foreign objects pass through the gap between adjacent stop bars 31 and minimizing the probability of foreign objects passing through the gap. The end parts of the stop bars 31 on both sides of the glass substrate 100 are respectively located outside the glass substrate 100, so that the stop bars 31 can also cover the edge positions of the glass substrate 100, so that the multiple stop bars 31 can cover the entire cross-section of the glass substrate 100, and foreign objects located at the edge of the glass substrate 100 can also be scraped off or detected.

[0035] As Figure 1 and Figure 3 shown, the shape of the bracket 10 in this embodiment is a rectangular frame, including a short side along the conveying direction of the glass substrate 100 and a long side perpendicular to the conveying direction. Multiple guide rails 20 are respectively arranged on the bracket 10 and are parallel to the short side.

[0036] Specifically, the transmission line for transporting the glass substrate 100 includes multiple rows of rollers arranged side by side. Through the rotation of the rollers, the glass substrate 100 can move on the transmission line. Multiple rollers are arranged at intervals in each row. The bracket 10 of the embodiment of the present invention is arranged close to one row of rollers. Guide rails 20 are arranged on both sides of each roller in this row. The sliders 32 on both sides of the stop bar 31 are respectively slidably engaged with the guide rails 20 on both sides of the roller, so that each stop bar 31 corresponds to one roller. That is, the arrangement positions of the guide rails 20, the sliders 32, and the stop bar 31 should avoid interfering with the normal rotation of the rollers and avoid the transportation of the glass substrate 100.

[0037] In one embodiment, as Figure 2 shown, the detection unit includes a detection circuit, multiple resistance sheets 41 fixedly bonded to the surface of the guide rail 20, and multiple sliding sheets 42 with one end connected to the slider 32 and the other end in contact with the resistance sheet 41. The detection circuit is electrically connected to the multiple resistance sheets 41 and the sliding sheets 42 respectively. When the stop bar 31 drives the slider 32 to move, the slider 32 can drive the sliding sheet 42 to move, so that the detection circuit detects a change in the resistance value. Thus, the detection circuit can detect the movement of the stop bar 31 at this place, and further send a signal that there is a foreign object attached to the back of the glass substrate 100 at the position of the stop bar 31 to the outside. It can be understood that the stop bar 31 slides along the guide rail 20 through the sliders 32 on both sides thereof. The resistance sheet 41 can be arranged on any one of the two guide rails 20. That is to say, one of the two guide rails 20 corresponding to each stop bar 31 is provided with the resistance sheet 41, or the resistance sheet 41 can also be arranged on the bracket 10, and one end of the sliding sheet 42 can also be connected to the stop bar 31, as long as the resistance sheet 41 is in a fixed state and the sliding sheet 42 can move with the stop bar 31. The detection circuit can detect the change in the resistance value by detecting the change in voltage or current. Those skilled in the art can choose according to the actual situation, and the present invention does not make special limitations in this regard.

[0038] Furthermore, the detection unit may further include an alarm device, such as a sound - emitting or light - emitting device. When the detection unit detects the movement of the stop bar 31, the detection unit sends a start command to the alarm device, and the alarm device emits sound and light to the outside to prompt the operator to process the glass substrate 100. The alarm device can also be set to multiple ones, corresponding to multiple stop bars 31 one by one. After the stop bar 31 moves, the corresponding alarm device is started, so as to facilitate the operator to locate the position of the foreign object on the surface of the glass substrate 100. After the operator processes the glass substrate 100, for example, after taking away the glass substrate 100 that triggers the alarm from the transmission line, a reset operation is performed on the detection unit to stop the alarm device and return the stop bar 31 to its initial position.

[0039] In one embodiment, as Figure 4As shown in the figure, the detection unit includes a detection circuit, as well as a plurality of light sources 51 and light receivers 52 respectively located on both sides of the slider 32. The detection circuit is electrically connected to the plurality of light receivers 52 respectively, and the light receivers 52 can receive the light emitted by the light sources 51. The plurality of light sources 51 and light receivers 52 are located on both sides of the slider 32 on one side of each shift lever 31. Since the slider 32 is on the optical path between the light source 51 and the light receiver 52, when the shift lever 31 drives the slider 32 to move, the slider 32 will block the light, thereby changing the light received by the light receiver 52. The detection circuit can detect the movement of the shift lever 31 by the change in the optical signal received by the light receiver 52.

[0040] In some embodiments, the detection unit is also connected to the control unit of the transmission mechanism for conveying the glass substrate. When the detection unit detects the movement of the shift lever, the control unit can stop the operation of the transmission mechanism according to the signal sent by the detection unit, so that the glass substrate 100 stops moving, facilitating the operator to find the glass substrate 100. The detection unit can send information about the shift lever 31 that generates movement to the control unit, and the control unit performs positioning display on its terminal display, facilitating the operator to process the glass substrate 100.

[0041] As Figure 5 As shown in the figure, in some embodiments, the bracket 10 includes a plurality of vertical rods 11 and a cross bar 12. The cross bar 12 is connected to the frame of the transmission device of the glass substrate 100. One end of the vertical rod 11 is connected to the rod body of the cross bar 12, and the guide rail 20 is connected to the other end of the vertical rod 11. By splicing a plurality of vertical rods 11 and a cross bar 12 into a frame-shaped bracket 10, it is convenient to arrange the bracket 10 under the glass substrate 100 and can be fixedly connected to the transmission device. The bracket 10 with this structure is also convenient for leveling the guide rail 20, making the guide rail 20 parallel to the conveying direction of the glass substrate 100. Since the gap between the top surface of the shift lever 31 and the back surface of the glass substrate 100 is small, it is necessary to strictly ensure that the guide rail 20 is parallel to the conveying direction of the glass substrate 100. After installing the shift lever 31 on the guide rail 20 through the slider 32, it is possible to avoid the problem that the moving direction of the shift lever 31 is not parallel to the conveying direction of the glass substrate 100 and prevent the shift lever 31 from contacting the glass substrate 100.

[0042] In some embodiments, the gap between the top surface of the shift lever 31 and the back surface of the glass substrate 100 ranges from 150 to 300 microns. It can be understood that when foreign matter is smaller than this gap value, it generally does not affect the quality of the glass substrate 100, such as foreign matter with a particle size less than 150 microns. Those skilled in the art can control the size of the allowable foreign matter particles by adjusting the distance between the shift lever 31 and the glass substrate 100.

[0043] The gaps between multiple shift levers 31 and the back surface of the glass substrate 100 can be the same or different. For example, the shift lever 31 at the center of the glass substrate 100 can be closer to the back surface of the glass substrate 100. That is to say, the gap between the shift lever 31 at the center of the glass substrate 100 and the back surface of the glass substrate 100 is smaller than the gap between the shift lever 31 at the edge of the glass substrate 100 and the back surface of the glass substrate 100. Since the display weight at the center of the glass substrate 100 is greater, by setting different gap values, the installation difficulty of the device can be reduced without affecting the display quality. Specifically, the gap between the shift lever 31 at the center of the glass substrate 100 and the back surface of the glass substrate 100 is 200 microns, and the gap between the shift lever 31 at the edge of the glass substrate 100 and the back surface of the glass substrate 100 is 300 microns, thereby reducing the installation difficulty of the shift lever 31. Or, the gaps between multiple shift levers 31 and the back surface of the glass substrate 100 are all 200 microns, but the installation error of the shift lever 31 at the center of the glass substrate 100 is 50 microns, and the installation error of the shift lever 31 at the edge of the glass substrate 100 is 100 microns. By specifying different installation errors, the installation difficulty of the shift lever 31 can be reduced, and the installation and debugging efficiency of the device can be improved.

[0044] The shift lever 31 is made of a light hard metal material, such as stainless steel or aluminum alloy. Those skilled in the art can select the material and length of the shift lever 31 according to actual needs to determine the weight of the shift lever 31, so as to correspond to the adhesion force between the foreign object and the glass substrate 100. That is, the heavier the shift lever 31, the more capable it is of scraping off foreign objects with a greater adhesion force. The cross-sectional shape of the shift lever 31 is set as a rectangle, and there is a gap between its top surface and the back surface of the glass substrate 100. The edge of the shift lever 31 facing the incoming material direction is set to be relatively sharp, which is convenient for scraping foreign objects from the surface of the glass substrate 100, or preventing foreign objects from crossing the shift lever 31 and squeezing into the gap between the shift lever 31 and the glass substrate 100, thereby preventing the problem of missed detection.

[0045] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by terms such as "upper" and "lower" is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of the present invention. Unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0046] It should also be noted that in the description of the present invention, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprising", "including" or any other variation thereof are intended to cover non-exclusive inclusion, such that a process, method, article or device comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, article or device comprising the element.

[0047] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, rather than limitations on the implementation manners of the present invention. For those of ordinary skill in the art, based on the above description, other different forms of changes or variations can be made. It is impossible to enumerate all the implementation manners here. Any obvious changes or variations derived from the technical solutions of the present invention still fall within the protection scope of the present invention.

Claims

1. A device for detecting foreign objects on the surface of a glass substrate, characterized in that, it includes: a bracket, the bracket is arranged perpendicular to the conveying direction of the glass substrate and is located below the glass substrate, and the bracket is arranged as a rectangular frame; guide rails, a plurality of the guide rails are arranged on the bracket along the conveying direction of the glass substrate, and the plurality of guide rails are fixedly combined on the rectangular frame; sliding parts, a plurality of the sliding parts are arranged side by side along the direction perpendicular to the conveying direction of the glass substrate, each of the sliding parts includes a stop bar and sliders fixedly connected to both ends of the stop bar, the sliders are slidably connected with the guide rails so that the stop bar can slide along the conveying direction of the glass substrate, there is a gap between the top surface of the stop bar and the surface of the glass substrate, the value range of the gap is 150-300 microns, the stop bar is made of a hard metal material, and the cross-sectional shape of the stop bar is arranged as a rectangle; and a detection unit, the detection unit is used to detect the displacement of the stop bar, the detection unit includes a detection circuit, a plurality of resistance sheets fixedly combined on the surface of the guide rail, and a plurality of sliding sheets with one end connected to the slider and the other end in contact with the resistance sheet, the detection circuit detects the change of the resistance value between the resistance sheet and the sliding sheet to detect the displacement of the stop bar, alternatively, the detection unit includes a detection circuit, and a plurality of light sources and light receivers respectively located on both sides of the slider. When the slider moves, the light receiver can receive the change of the light emitted by the light source, and the detection circuit detects the light change signal of the light receiver to detect the displacement of the stop bar.

2. The device according to claim 1, characterized in that, the two ends of the stop bars of the plurality of sliding parts are arranged close to each other, and the two ends of the stop bars located on both sides of the glass substrate are respectively located outside the glass substrate.

3. The device according to claim 1, characterized in that, the transmission mechanism for conveying the glass substrate includes multiple rows of rollers arranged in parallel, and the guide rails are respectively arranged on both sides of one row of rollers so that one roller corresponds to one stop bar.

4. The device according to claim 1, characterized in that, the detection unit is also connected to the control unit of the transmission mechanism for conveying the glass substrate. When the detection unit detects the movement of the stop bar, the control unit can stop the operation of the transmission mechanism according to the signal sent by the detection unit.

5. The device according to claim 1, characterized in that, the bracket includes a plurality of cross bars connected to the frame of the transmission device for conveying the glass substrate, and a plurality of vertical bars connected to the cross bars, the cross bars are arranged along the conveying direction of the glass substrate, and the guide rails are arranged at the top ends of the vertical bars.

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