WO2010131610A1

WO2010131610A1 - Method for setting working position of grindstone for grinding glass end face

Info

Publication number: WO2010131610A1
Application number: PCT/JP2010/057837
Authority: WO
Inventors: 秀晴鳥井; 祐介今里
Original assignee: 旭硝子株式会社
Priority date: 2009-05-15
Filing date: 2010-05-07
Publication date: 2010-11-18
Also published as: TW201100199A; CN102427913B; CN102427913A; KR20120016242A; JPWO2010131610A1

Abstract

Disclosed is a method for setting a working position of a grindstone for grinding a glass end face with respect to an end face of a glass plate in a machining device for grinding an end face of a glass plate by pressing a rotating grindstone on the end face of the glass plate, the method comprising stopping the rotation of the grindstone, moving the grindstone toward the end face of the glass plate using power of a servomotor, and setting the working position of the grindstone on the basis of variations in the load of the servomotor generated when the grindstone is brought into contact with the end face of the glass plate and a grinding allowance for the end face of the glass plate.

Description

Processing position setting method for grinding wheel for glass end face grinding

The present invention relates to a method for setting a processing position of a grindstone for grinding a glass end face, and particularly when chamfering or mirror-finishing an end face of an FPD (Flat Panel Display) glass substrate such as a liquid crystal display glass substrate or a plasma display glass substrate. In addition, the present invention relates to a processing position setting method for a glass end surface grinding grind performed to set a processing position of a grindstone.

In an end surface grinding device such as a chamfering device for chamfering the end surface of a glass substrate for FPD or a mirror surface processing device for mirroring the chamfered portion of the end surface, the end surface of the actual glass substrate is generally replaced after the grindstone is replaced The processing position of the grindstone was manually set by inputting the correction value in the Y-axis direction several times after confirming the processing condition of the end face. Here, the processing position refers to the position of the grindstone when starting to move the grindstone used for processing in a direction parallel to the side of the rectangular glass substrate (X-axis direction). The Y axis refers to an axis that moves the grindstone toward the end surface of the glass substrate, that is, an axis that is orthogonal to the side of the rectangular glass substrate. In the mirror surface processing, the grindstone may be moved in the Y-axis direction to the set processing position, and then the grindstone may be moved in the X-axis direction to mirror the end surface of the glass substrate. In this case, the unevenness of the end surface caused by the chamfering process before the mirror surface processing is ground by the mirror surface processing. As the movement mechanism in the Y-axis direction, a servo motor capable of position control and a ball screw driven by this servo motor are generally used.

In such a grinding apparatus, when the grindstone used for processing is moved in the Y-axis direction toward the end surface of the glass substrate, the position of the grindstone where the grindstone is in contact with the end portion of the rectangular glass substrate is the zero point position. Call it.

On the other hand, a method for automatically setting the processing position of the grindstone in the Y-axis direction is also known. In this automatic setting method, the grindstone is moved in the Y-axis direction by the servo motor while the grindstone is rotated by the grindstone rotating motor (inverter motor), and the load fluctuation of the current value of the grindstone rotating motor exceeds a predetermined threshold value. In this case, the processing position in the Y-axis direction is set by determining that the grindstone is in contact with the end surface of the glass substrate.

Patent Document 1 discloses a glass substrate that measures the height position of a suction stage on which a liquid crystal display panel to be chamfered is mounted with a laser displacement meter and automatically adjusts the height position of a grindstone based on the height position information. A chamfering apparatus is disclosed. That is, in the chamfering device of Patent Document 1, when the height position information of the suction stage measured by the laser displacement meter is output to the control unit of the chamfering device, the control unit receives the conversion data that is input in advance. Is used to calculate an appropriate height of the grindstone, and the grindstone is adjusted in the vertical direction by the robot so as to obtain the height.

The processing position adjustment of the grindstone in Patent Document 1 is to adjust the position in the height direction of the grindstone with respect to the end surface of the glass substrate, and not to adjust the processing position in the Y-axis direction described above.

Japanese Unexamined Patent Publication No. 2003-25198

In the conventional processing position setting method in which the processing position of the grinding wheel is set by changing the load of the current value of the grinding wheel rotation motor while contacting the end surface of the glass plate while rotating the grinding stone, the rotating grinding stone contacts the end surface of the glass plate. Due to variations in grinding resistance when touching, there may be a large deviation in positional accuracy. In this case, the grindstone may move too much in the Y-axis direction. There was a risk of damage. Further, even if the damage can be prevented, the grindstone rotates at a high speed, so that there is a problem that a shaving mark that is defective in quality is generated on the glass plate. Therefore, in the conventional processing position setting method, since the glass plate as a product cannot be used for setting the processing position of the grindstone, it is necessary to use a dummy glass plate. In addition, since it is necessary to replace the dummy glass plate with the product glass plate, there is a problem in that the productivity of the FPD glass substrate is lowered.

The present invention has been made in view of such circumstances, and can suppress variations in the processing position accuracy of the grindstone with respect to the end surface of the glass plate, and can prevent the glass plate and the grindstone from being damaged. It is an object to provide a processing position setting method for a grinding wheel for grinding a glass end face, which can improve quality and further improve productivity by using a glass plate as a product for setting a processing position. .

In order to achieve the above object, the present invention sets the processing position of the grindstone with respect to the end surface of the glass plate in a processing apparatus that grinds the end surface of the glass plate by pressing a rotating grindstone against the end surface of the glass plate. A method for setting a processing position of a grindstone for grinding a glass end surface, the rotation of the grindstone is stopped, the grindstone is moved toward the end surface of the glass plate by the power of a servo motor, and the grindstone is moved to the end surface of the glass plate. Provided is a processing position setting method for a grindstone for grinding a glass end surface, wherein the processing position of the grindstone is set based on a fluctuation value of a load of the servo motor generated upon contact and a glass end surface grinding allowance.

According to the present invention, the processing point is not set by the load fluctuation of the current value of the grindstone rotating motor, but the zero point of the grindstone is based on the load fluctuation value of the servo motor that moves the grindstone toward the end surface of the glass plate. Set the position. In this case, since the grindstone does not need to be rotated, the rotation is stopped.

That is, when the grindstone in the rotation stop state is moved toward the end surface of the glass plate by the servo motor, the load on the servo motor slightly fluctuates due to the feed load. Then, when the grindstone comes into contact with the end face of the glass plate, the load of the servo motor greatly fluctuates immediately thereafter, and when the fluctuating load exceeds a predetermined threshold, the servo motor is stopped to stop the movement of the grindstone. The stop position is set as the zero point position, and the position moved from the zero point position by the grinding allowance in the Y-axis direction is set as the machining position. The predetermined threshold value of the load is a value exceeding the load (feed load) required for the rotation of the ball screw device by the servo motor.

Therefore, according to the machining position setting method of the present invention, the position when the grindstone in the rotation stop state contacts the end face of the glass plate is set as the zero point position, and the position moved from the zero point position by the grinding allowance in the Y-axis direction is set. Since the processing position is set, variation in the processing position accuracy of the grindstone with respect to the end surface of the glass plate can be suppressed. Thereby, damage to the glass plate and the grindstone can be prevented, and the quality of the glass plate is improved because no shaving mark is attached to the glass plate. Therefore, since the glass plate used as a product can be used for processing position setting, without using a dummy glass plate by these effects, productivity of a glass plate improves. Although it has been described that the processing position of the grindstone is set in a state in which the rotation is stopped, the processing position may be set while rotating the grindstone as long as the rotational speed does not contribute to grinding.

Further, the grindstone of the present invention is preferably a mirror grindstone.

In the chamfering device for glass plate, the grinding allowance with the grindstone is as large as several hundreds μm, so high precision is not required at the machining position. However, in the mirror finishing device, the grinding allowance is as small as several μm, so the precision at the machining position is high. Is required. Therefore, it is preferable that the processing position set by the processing position setting method of the present invention is a processing position of a grindstone for mirror surface processing.

Furthermore, the glass plate of the present invention is preferably a glass substrate for FPD.

The processing position setting method of the present invention can also be applied to an architectural glass plate, but is suitable for setting the processing position of an end surface grinding apparatus for an FPD glass plate that requires high accuracy.

As described above, according to the processing position setting method for the glass end face grinding wheel according to the present invention, the position when the rotation stopped grindstone comes into contact with the end face of the glass plate is set as the zero point position. Since the position moved by the grinding allowance in the axial direction is set as the processing position, variation in the processing position accuracy of the grindstone with respect to the end surface of the glass plate can be suppressed, thereby preventing breakage of the glass plate and the grindstone. . In addition, since no shaving mark is attached to the glass plate, the quality of the glass plate is improved. Therefore, since the glass plate used as a product can be used for processing position setting, without using a dummy glass plate by these effects, productivity of a glass plate improves.

The top view of the mirror surface processing apparatus to which the processing position setting method of the grindstone for glass end surface grinding of embodiment was applied Side view of the main part of the mirror finishing apparatus shown in FIG. Explanatory drawing which shows the load fluctuation of the servomotor of the mirror surface processing apparatus shown in FIG. Flowchart showing an example of software operation based on the machining position setting method

Hereinafter, preferred embodiments of a processing position setting method for a glass end surface grinding wheel according to the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a plan view of a glass end surface grinding apparatus 10 to which a processing position setting method for a glass end surface grinding wheel of the present invention is applied, and FIG. 2 is a side view of a main part of the glass end surface grinding apparatus 10 shown in FIG. FIG. This glass end surface grinding apparatus 10 is an apparatus for mirror-treating a chamfered portion processed on an end surface of an FPD glass substrate 12 that is a processing object, using a mirror surface processing grindstone 14.

The glass end surface grinding apparatus 10 has a table 16 that sucks and holds a glass substrate 12 formed in a rectangular shape, and the glass substrate 12 is sucked and held on the table 16 with a predetermined positional accuracy.

The grindstone 14 is detachably fixed to a rotating shaft 20 of an inverter motor 18 that is a grindstone rotating motor, and is rotated at a predetermined rotational speed by the power of the inverter motor 18. The grindstone 14 is moved along the side portion 13 of the glass substrate 12 in a state of being rotated by the inverter motor 18 by being moved to a processing position to be described later and being brought into contact with the end surface of the side portion 13 of the glass substrate 12. . Thereby, the end surface of the side portion 13 of the glass substrate 12 is mirror-finished.

The inverter motor 18 is mounted on a nut portion 22, and this nut portion 22 is screwed into a ball screw 24 laid in the Y-axis direction. The ball screw 24 is connected to a rotation shaft (not shown) of the servo motor 26. Therefore, when the servo motor 26 is driven and the ball screw 24 is rotated, the grindstone 14 moves in the Y-axis direction with a feed accuracy of submicron order via the nut portion 22 and the inverter motor 18. Therefore, when the ball screw 24 is rotated forward / reversely by the servo motor 26, the grindstone 14 moves forward / backward with respect to the side portion 13 of the glass substrate 12.

On the other hand, the nut portion 22 is screwed into a feed screw 28 laid in the X-axis direction orthogonal to the Y-axis direction, and the feed screw 28 is connected to a rotating shaft (not shown) of the motor 30. Therefore, when the motor 30 is driven to rotate the feed screw 28, the grindstone 14 moves in the X-axis direction via the nut portion 22 and the inverter motor 18. Therefore, when the feed screw 28 is rotated forward / reversely by the motor 30, the grindstone 14 reciprocates with respect to the side portion 13 of the glass substrate 12.

Next, a processing position setting method of the grindstone 14 by the glass end surface grinding apparatus 10 configured as described above will be described.

The setting of the processing position of the grindstone 14, which will be described below, that is, the condition setting in the Y-axis direction of the grindstone 14 is performed each time the worn grindstone 14 is replaced with a new grindstone 14. In the mirror finishing, the grindstone 14 is moved forward in the Y-axis direction toward the side portion 13 of the glass substrate 12, and the position at which the grindstone 14 contacts the side portion 13 of the glass substrate 12 is set as the zero point position. And stored in the control unit 32. In actual mirror finishing, the grindstone 14 is moved in the Y-axis direction by the grinding allowance from the zero point position stored in the control unit 32. Thereafter, the grindstone 14 is moved in the X-axis direction, whereby the glass substrate 12 is moved. The end surface of the side portion 13 is mirror-finished.

Describing the processing position setting method, first, the grindstone 14 is retracted from the side portion 13 of the glass substrate 12 in a predetermined amount in the Y-axis direction. At this time, the grindstone 14 is stopped.

Next, when the grindstone 14 is moved in the Y-axis direction by the power of the servo motor 26 toward the side portion 13 of the glass substrate 12, the load of the servo motor slightly fluctuates due to the feed load. When the grindstone 14 comes into contact with the end face of the side portion 13 of the glass substrate 12, the load on the servo motor 26 greatly fluctuates immediately thereafter, and the servo motor 26 is stopped when the fluctuating load exceeds a predetermined threshold. Then, the movement of the grindstone 14 in the Y-axis direction is stopped, and the stop position is set as the zero point position and stored in the control unit 32. The threshold value is set to a value exceeding the load (feed load) required for rotation of the ball screw device by the servo motor. Furthermore, the position moved by the grinding allowance in the Y-axis direction from the zero point position is set as the machining position.

In other words, according to the machining position setting method of the embodiment, the servo motor that moves the grindstone 14 toward the side portion 13 of the glass substrate 12 instead of setting the machining position by the load fluctuation of the current value of the inverter motor 18. The zero point position of the grindstone 14 is set based on the load fluctuation value 26, and the position moved from the zero point position by the grinding allowance in the Y-axis direction is set as the machining position.

FIG. 3 shows a graph representing the load variation of the servo motor 26. The vertical axis of the graph of FIG. 3 indicates the load (%) of the servo motor 26, and the horizontal axis indicates the feed position of the grindstone 14 in the Y-axis direction.

The normal load (feed load) is determined by the rotational resistance of the ball screw 24, the feed speed of the ball screw 24, and the like, and is in the range of A to B (%) according to the graph of FIG. Therefore, the position where the grindstone 14 is in contact with the side portion 13 of the glass substrate 12 is a load (threshold value) exceeding the upper limit A (%) of the range, and is a position where the control unit 32 detects the load. That is, when the control unit 32 detects a load exceeding A (%), the control unit 32 recognizes and stores the position as a zero point position.

Therefore, according to the processing position setting method of the embodiment, the position when the grindstone 14 in the rotation stop state contacts the end surface of the side portion 13 of the glass substrate 12 is set as the zero point position, and the zero point position is changed to the Y axis direction. Since the position moved by the grinding allowance is set as the processing position, variations in the processing position accuracy of the grindstone 14 with respect to the end surface of the glass substrate 12 can be suppressed. Thereby, the glass substrate 12 and the grindstone 14 can be prevented from being damaged, and the quality of the glass substrate 12 is improved because the glass substrate 12 is not marked by the grinding stone 14.

Therefore, because of these effects, the glass substrate 12 as a product can be used for processing position setting without using a dummy glass substrate, so that the productivity of the glass substrate 12 is improved.

In the embodiment, the processing position setting method of the mirror-finishing grindstone 14 has been described. However, the present invention can also be applied to the processing position setting of the chamfering grindstone. However, in the chamfering process, the grinding allowance with the grindstone is as large as several hundreds μm, so that high accuracy is not required for the processing position. On the other hand, in the mirror surface processing, since the grinding allowance is as small as several μ, high accuracy is required for the processing position. Therefore, it is preferable that the grindstone set by the machining position setting method according to the embodiment is the grindstone 14 for mirror surface machining.

Moreover, in embodiment, although the processing position setting method of the grindstone 14 which mirror-processes the end surface of the glass substrate 12 for FPD was demonstrated, the glass substrate made into object is not limited to the glass substrate for FPD, For example, a building Glass plates for solar cells and glass substrates for solar cells may be used. However, the processing position setting method of the embodiment is suitable for the processing position setting method of the end surface grinding apparatus for FPD glass sheets that requires high accuracy.

Furthermore, in the embodiment, the glass end surface grinding apparatus 10 that mirror-processes the side 13 of the glass substrate 12 is illustrated, but it can also be applied to a grinding apparatus that simultaneously mirrors two opposing sides of the glass substrate 12. The present invention can also be applied to a grinding apparatus that simultaneously mirrors the four sides of the glass substrate 12.

〔Example〕
Based on the machining position setting method of the embodiment, we created software that automatically stopped the grindstone and set the condition of the mirror surface grindstone with the torque load of the servo motor. Conditions could be set up 2 minutes or more earlier than the setting method, and the positional accuracy was also good. Further, no damage was caused by the grinding stone on the conditioned glass substrate, and no grinding stone damage was caused.

FIG. 4 is a flowchart showing an example of the operation of the software.

[Comparative example]
In the conventional processing position setting method, the glass substrate was broken and the grindstone was broken when conditions were set after the grindstone was replaced, and it was necessary to replace the grindstone again. In some cases, a loss of a plurality of glass substrates occurred.

Although this application has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention.
This application is based on a Japanese patent application filed on May 15, 2009 (Japanese Patent Application No. 2009-118891), the contents of which are incorporated herein by reference.

DESCRIPTION OF SYMBOLS 10 ... Glass end surface grinder 12 ... Glass substrate for FPD 13 ... Side part 14 ... Mirror surface processing grindstone 16 ... Table 18 ... Inverter motor 20 ... Rotating shaft 22 ... Nut part 24 ... Ball screw 26 ... Servo motor 28 ... Feed screw 30 ... Motor 32 ... Control unit

Claims

A processing position setting method of a grindstone for grinding a glass end face for setting a processing position of the grindstone with respect to an end face of the glass plate in a processing apparatus for grinding the end face of the glass plate by pressing a rotating grindstone against an end face of the glass plate Because
Stop the rotation of the grindstone,
The grindstone is moved by the power of the servo motor toward the end surface of the glass plate,
The processing position of the grindstone for glass end surface grinding is characterized in that the processing position of the grindstone is set based on the fluctuation value of the load of the servo motor generated when the grindstone contacts the end surface of the glass plate and the glass end surface grinding allowance. Setting method.
2. The processing position setting method for a glass end grinding grindstone according to claim 1, wherein the grindstone is a mirror finishing grindstone.
The method for setting a processing position of a glass end grinding grindstone according to claim 1 or 2, wherein the glass plate is a glass substrate for FPD.