JP2018103320A - End surface processing method for glass plate, manufacturing method and glass plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent production of glass powder from an end surface to the utmost by improving the end surface property of a glass plate.SOLUTION: An end surface processing method for a glass plate according to the present invention includes: a preparation step S1 of preparing a subassembly 25 for a grindstone 11 (12) with a static run-out of 40 μm or less and a dynamic balance 50 g mm or less and a flange 20 for attaching the grindstone; and an end surface processing step S3 of applying predetermined processing to an end surface 2 of the glass plate 1 by attaching the subassembly 25 to a spindle 19.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a glass plate end surface processing method, a manufacturing method, and a glass plate, and more particularly to a technique for improving the end surface properties of the glass plate.

  In recent years, in order to respond to a request for improvement in production efficiency of a liquid crystal display or the like, a demand for improvement in manufacturing efficiency of a glass substrate used for the display or the like is increasing. Here, in the production of a glass substrate, one or a plurality of glass substrates are cut out from a large glass original plate (molded original plate). Thereby, the glass substrate of a desired dimension can be acquired.

  On the other hand, since the end surface of the glass substrate cut out from the glass original plate is usually a cut surface or a folded surface, there are often minute scratches (defects). If there is a scratch on the end surface of the glass substrate, cracks or the like are generated from the scratch. Therefore, grinding (rough polishing) and polishing (finish polishing) are applied to the end surface of the glass substrate to prevent this. Is done. This type of end face processing is performed, for example, by bringing a grindstone in a state where the thickness direction of the glass substrate and the rotation axis coincide with the end face of the glass substrate (see, for example, Patent Document 1).

International Publication WO2013 / 187400

  By the way, in the production process of the liquid crystal display, there are various processes performed on the glass substrate such as a film forming process, an exposure process, and an etching process. Among them, the purpose of the etching process is to melt a part of the metal film formed on the glass substrate, but actually the glass on the end face is also melted by etching. Along with this, a part of the glass on the end face is peeled off to become glass powder, which may adhere to the main surface (flat surface having the largest area) of the glass plate. Since the adhesion of glass powder causes a film formation failure and a disconnection failure, it is necessary to avoid the generation of this kind of glass powder as much as possible.

  When the end face property of the glass plate is rough, the etching solution easily penetrates and glass powder is easily generated. The roughness (for example, surface roughness) of the glass plate end face is improved mainly by polishing among grinding and polishing. However, the end face after grinding may have a waviness with a relatively long period of unevenness. This undulation is, for example, undulation that appears in the same order as the undulation curve of the arithmetic average undulation Wa (hereinafter referred to as “micro undulation”). Since it becomes difficult to contact, there exists a possibility that it cannot fully grind | polish. Since the portion that remains without being sufficiently polished is still rough, glass powder is easily generated. In particular, with the recent increase in definition of liquid crystal displays, the number of film forming steps and the number of etching steps on a glass substrate tend to increase.

  In view of the above circumstances, the technical problem to be solved by the present invention is to prevent the generation of glass powder from the end face as much as possible by improving the end face properties of the glass plate.

  The solution to the above problem is achieved by the method for processing an end face of a glass plate according to the present invention. That is, in this end face processing method, a grindstone is attached to a spindle rotated by a motor via a grindstone mounting flange, and the grindstone is brought into contact with the end face of the glass plate while rotating the grindstone by rotating the spindle. A glass plate end face processing method for applying a predetermined processing to a sub-assembly of a grindstone and a grindstone mounting flange such that a static runout is 40 μm or less and a dynamic balance is 50 g · mm or less. It is characterized in that it comprises a preparation step and an end face processing step of attaching a subassembly to the spindle and performing a predetermined processing on the end face of the glass plate.

  The present invention has been made by paying attention to the static runout and dynamic balance in the sub-assembly state of the grindstone attached to the spindle and the grindstone mounting flange. That is, the dynamic balance of the grindstone rotation system including the grindstone and the spindle is also affected by the assembly accuracy of the grindstone and the grindstone mounting flange. Even if it adjusts, the contact state of an end surface and a grindstone is not necessarily improved enough. For this reason, the adjusting means requires excessive accuracy with respect to static vibration. On the other hand, if a grindstone and a grindstone mounting flange subassembly having a static runout and a dynamic balance in the above range are prepared, and the subassembly is mounted on a spindle to perform predetermined processing on the glass plate end face. The above-described micro swell can be stably eliminated or reduced. Thereby, since it can polish without leak over the whole end surface, it becomes possible to improve the surface roughness of an end surface (the value of surface roughness is made small). Of course, by adjusting the static runout and dynamic balance of the sub-assembly to a predetermined value or less, the accuracy of the polishing process can also be improved, and this can also effectively improve the surface roughness. Become.

  Moreover, in the end surface processing method of the glass plate which concerns on this invention, in a preparatory process, it is made to prepare the grindstone attachment flange from which dynamic balance will be 20 g * mm or less, and the grindstone from which dynamic balance will be 20 g * mm or less. Also good.

  As described above, by preparing the grindstone and the grindstone mounting flange with the respective dynamic balances adjusted to the above range, the dynamic balance in the sub-assembly state can be easily set within the above range.

  Further, in the method for processing an end face of a glass plate according to the present invention, with the subassembly attached to the spindle, the rotation speed is changed while measuring the vibration in the direction perpendicular to the rotation axis of the spindle, and the vibration amplitude is 50 μm. A rotation speed selection step for selecting the rotation speed to be described below may be further provided, and the end face may be subjected to predetermined processing using the selected rotation speed in the end face machining step.

  By selecting and using the rotational speed in this way, it becomes possible to reliably avoid the resonance region of the grindstone rotating system including the grindstone and to perform end face processing. Therefore, it is possible to obtain an end face with stable quality (surface roughness).

  Moreover, in the end surface processing method of the glass plate which concerns on this invention, you may make it process an end surface in the state which maintained the contact pressure of a grindstone and an end surface at a fixed magnitude | size in an end surface processing process.

  In this way, by adopting a method (so-called constant pressure method) that processes the end surface while maintaining a constant contact pressure between the grindstone and the end surface, the total machining allowance can be reduced. It has the advantage that the speed can be increased relatively easily. Therefore, as in the present invention, when adjusting the static run-out and dynamic balance of the sub-assembly of the grindstone and the grindstone mounting flange to stabilize the contact state with the end face, speeding up and quality of the end face processing Both stabilization can be easily achieved.

  Moreover, the solution of the said subject is achieved also by the manufacturing method of the glass plate which concerns on this invention. That is, this manufacturing method includes a step of preparing a glass plate and a step of processing the end surface of the prepared glass plate by the above-described end surface processing method of the glass plate.

  According to the said structure, similarly to the end surface processing method of the glass plate which concerns on this invention, micro waviness can be eliminated or reduced stably. Thereby, since it can polish without leak over the whole end surface, it becomes possible to improve the surface roughness of an end surface (the value of surface roughness is made small). Of course, by suppressing the static runout and dynamic balance of the sub-assembly to a predetermined value or less, the accuracy of the polishing process can be increased, and this also can effectively improve the surface roughness. Become.

  Moreover, the solution of the said subject is achieved also by the glass plate which concerns on this invention. That is, this glass plate is a glass plate in a state in which predetermined processing with a grindstone is performed on the end face, and is characterized by a point that the arithmetic average waviness Wa of the end face is less than 2.7 μm.

  In this way, if the arithmetic average waviness Wa of the end face in a state where the predetermined processing by the grindstone is performed is set in the above range, the above-described micro waviness is eliminated as in the end face processing method according to the present invention. Or it can be reduced. As a result, the entire end surface can be made a polished surface without omission, and the surface roughness of the end surface can be improved.

  Moreover, in the glass plate which concerns on this invention, 1.2 micrometers or less may be sufficient as arithmetic mean roughness Ra of an end surface.

  If the arithmetic average roughness Ra of the end face of the glass plate is within the above range, it is preferable because the generation of glass powder can be prevented to a necessary and sufficient level.

  Moreover, in the glass plate which concerns on this invention, the protrusion valley part depth Rvk of an end surface may be 2.5 micrometers or less.

  If the protruding valley depth Rvk of the end face is within the above range, the glass powder generated during the end face processing by the grindstone is greatly reduced in the possibility of being held in the recesses included in the end face, and the glass from the end face at the time of etching is reduced. It becomes possible to prevent detachment of the powder as much as possible.

  As described above, according to the present invention, it is possible to prevent the generation of glass powder from the end face as much as possible by improving the end face properties of the glass plate.

It is a schematic plan view of the end surface processing apparatus of the glass plate which concerns on one Embodiment of this invention. It is a principal part side view of the grindstone rotating system shown in FIG. It is the wave | undulation curve of the glass plate end surface obtained by the other end surface processing method. It is a wave | undulation curve of the glass plate end surface obtained with the end surface processing method which concerns on this invention. It is a graph which shows the relationship between the dynamic balance of the subassembly containing a grindstone, and the arithmetic mean wave | undulation of the glass plate end surface. It is a graph which shows the relationship between the dynamic balance of the subassembly containing a grindstone, and the arithmetic mean roughness of a glass plate end surface. It is a graph which shows the relationship between the dynamic balance of the subassembly containing a grindstone, and the protrusion valley part depth of a glass plate end surface.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS. First, an outline of an end face processing apparatus used in the manufacturing method and the end face processing method according to the present embodiment will be described with reference to FIGS. 1 and 2.

  As shown in FIG. 1, the end surface processing apparatus 10 performs predetermined processing on the end surface 2 of the glass plate 1, and includes a motor 13 that rotationally drives the grindstones 11, 12 as end surface processing portions, An arm member 14 that rotatably supports 12 and a servo mechanism 15 that causes the arm member 14 to generate a force by which the grindstones 11 and 12 press the end surface 2 of the glass plate 1 are mainly provided.

  As the motor 13, for example, a synchronous motor that rotates in synchronization with a rotational speed difference between a rotating magnetic field generated by an alternating current and a magnetic field generated by an armature current is used. The motor 13 can rotationally drive the grindstones 11 and 12 by open loop control without using closed loop control (feedback control). For example, as shown in FIG. 2, a spindle 19 is connected to the motor 13. In the present embodiment, the motor 13 and the spindle 19 have a common rotation axis Y.

  The arm member 14 is rotatably supported by the support shaft member 16. One end of the arm member 14 holds a spindle 19 rotatably, and the grindstones 11 and 12 are mounted on the spindle 19 via a grindstone mounting flange 20. The spindle 19 is directly connected to the spindle of the motor 13. The spindle 19 may be connected to the main shaft of the motor 13 via a belt or the like.

  The servo mechanism 15 includes a servo motor 17 that drives the arm member 14 so as to be rotatable around the support shaft member 16, a link mechanism 18 that connects the rotation shaft 17a of the servo motor 17 and the arm member 14, and a control unit. (Not shown). The link mechanism 18 includes a first link member 18a and a second link member 18b. One end of the first link member 18a is fixed to the rotation shaft 17a of the servo motor 17, and the other end is rotatably connected to one end of the second link member 18b via the first joint 18c. Yes. The other end of the second link member 18b is rotatably connected to the other end of the arm member 14 via the second joint 18d.

  In this case, when the rotation shaft 17a of the servo motor 17 rotates, for example, clockwise in FIG. 1, the arm member 14 also rotates clockwise around the support shaft member 16 by the link mechanism 18. Along with this, the force with which the grindstones 11 and 12 press the end surface 2 of the glass plate 1 decreases. On the other hand, when the rotation shaft 17a of the servo motor 17 rotates, for example, counterclockwise in FIG. 1, the arm member 14 also rotates counterclockwise around the support shaft member 16 by the link mechanism 18. Along with this, the force with which the grindstones 11 and 12 press the end surface 2 of the glass plate 1 increases.

  The control unit monitors the speed, torque, and position of the rotation shaft 17a of the servomotor 17. The position and pressing force of the grindstones 11 and 12 are controlled by rotating the rotation shaft 17a of the servo motor 17 according to the speed, torque and position.

  As shown in FIG. 2, the grindstone 11 (12) is attached to the spindle 19 via a grindstone mounting flange 20. More specifically, the grindstone 11 (12) is provided with a fitting hole 21, and the grindstone mounting flange 20 is provided with a fitting convex portion 22. By fitting the fitting convex portion 22 of the grindstone mounting flange 20 into the fitting hole 21 of the grindstone 11 (12), the grindstone 11 (12) is connected to the grindstone mounting flange 20, and the grindstone mounting flange 20 Positioning including centering of the grindstone 11 (12) with respect to is performed.

  The grindstone mounting flange 20 is provided with a fitting recess 23 on the side opposite to the fitting protrusion 22. The fitting recess 23 has a taper shape, and can be taper-fitted to the tip portion 24 of the spindle 19 which also has a taper shape. Therefore, for example, after preparing a subassembly 25 of a grindstone 11 (12) and a grindstone mounting flange 20 to be described later, the subassembly 25 is attached to the tip 24 of the spindle 19 so that the grindstone 11 (12) is automatically provided. Is centered and positioned with respect to the spindle 19.

  In the present embodiment, the end surface 2 of the glass plate 1 is mainly processed by two types of processing (grinding processing mainly for chamfering the end surface 2 and fine unevenness of the end surface 2. In order to perform (polishing), the grindstones 11 and 12 corresponding to each can be used. That is, the grain size of the abrasive grains in the second grinding wheel 12 for polishing is the same as or larger than the grain size of the abrasive grains in the first grinding wheel 11 for grinding. The grain size of the abrasive grains in the first grinding wheel 11 for grinding can be set to, for example, # 100 to # 1000, and the grain size of abrasive grains in the second grinding wheel 12 for polishing is set to, for example, # 200 to # 1000. be able to. Moreover, the diameter of the grindstones 11 and 12 is 100-200 mm, for example.

  The grindstone 11 (12) is a set of two, and as shown in FIG. 1, one or a plurality of sets of grindstones 11 (12) are arranged at positions facing each other with the glass plate 1 interposed therebetween. In FIG. 1, a set of first grinding wheels 11 and 11 for grinding and a set of second grinding wheels 12 and 12 for polishing are arranged. In this case, a total of four sets of motors 13, arm members 14, servo mechanisms 15, spindles 19, grinding wheel mounting flanges 20, etc. necessary for driving control of each grinding wheel 11 (12) are arranged on each grinding wheel 11, 12.

  The glass plate 1 to be processed by the end face processing apparatus 10 has a rectangular plate shape as shown in FIG. 1, for example. The thickness dimension of the glass plate 1 is preferably 0.05 mm to 10 mm, for example, and more preferably 0.2 mm to 0.7 mm. Of course, the glass plate 1 which can apply this invention is not limited to the said form. For example, the present invention can also be applied to a glass plate having a shape other than a rectangle (for example, a polygon) or a glass plate having a thickness that is out of 0.05 mm to 10 mm.

  The glass plate 1 can move relative to the grindstones 11 and 12 along a predetermined feed direction X. 1 shows a case where the glass plate 1 moves in the feed direction X and the grindstones 11 and 12 are fixed. Of course, the glass plate 1 is fixed and the grindstones 11 and 12 are connected to the feed direction X. May move in the opposite direction. At this time, either the glass plate 1 or the grindstones 11 and 12 may move, the other may be fixed, or both may move.

  Moreover, although the rotation direction of the grindstones 11 and 12 is arbitrary, it is good to determine the rotation direction of each grindstone 11 and 12 so that it may rotate in the direction facing the feed direction X of the glass plate 1, for example. In FIG. 1, it is preferable to determine the rotation direction of each of the grindstones 11 and 12 so that the upper grindstones 11 and 12 are counterclockwise and the lower grindstones 11 and 12 are clockwise.

  An example of end face processing for the end face 2 of the glass plate 1 using the end face processing apparatus 10 having the above-described configuration will be described.

  First, the grindstones 11 and 12 in a rotated state are arranged at predetermined positions by the rotation of the servo motor 17. In this state, the glass plate 1 is conveyed along the feed direction X, and the grindstones 11 and 12 are brought into contact with the end surface 2 of the glass plate 1. At the start of processing (when processing the portion indicated by reference numeral 2 a), the grindstones 11, 12 tend to separate from the glass plate 1 due to the impact accompanying the contact between the grindstones 11, 12 and the end surface 2 of the glass plate 1. In order to cope with this, the control unit performs feedback control (for example, PID control) of the speed and torque of the rotating shaft 17a of the servomotor 17. Specifically, the control unit detects the movement of the arm member 14 that moves together with the grindstones 11 and 12 based on the speed of the rotation shaft 17 a of the servomotor 17. In accordance with the detection result, the control unit controls the speed and torque of the rotating shaft 17a of the servo motor 17 so as to suppress the movement of the arm member 14. Thereby, the pressing force of the grindstones 11 and 12 is adjusted so that the grindstones 11 and 12 are not separated from the end surface 2 of the glass plate 1. For this reason, the bounce of the grindstones 11 and 12 at the start of processing can be prevented.

  Further, even in the processing of the intermediate portion in the conveyance direction (the portion between the portion indicated by reference numeral 2a and the portion indicated by reference numeral 2b) in the end surface 2 of the glass plate 1, the speed and torque of the rotating shaft 17a of the servo motor 17 are reduced. Perform feedback control. At that time, the ratio between the speed control and the torque control is changed to increase the torque control ratio. This ratio can be changed by changing the gain setting. Thereby, the processing amount of the end surface 2 of the glass plate 1 can be maintained constant in a conveyance direction.

  When the end face processing described above is completed, the contact between the grindstones 11 and 12 and the end face 2 of the glass plate 1 is released, so that the torque of the rotating shaft 17a of the servomotor 17 is rapidly reduced. Therefore, at the end of processing (when processing the portion indicated by reference numeral 2b), the control unit performs feedback control of the speed and torque of the rotating shaft 17a of the servomotor 17 so that the positions of the grindstones 11 and 12 are constant. .

  As described above, according to the end surface processing apparatus 10 shown in FIGS. 1 and 2, bounce of the grindstones 11 and 12 at the start of processing can be prevented, and the processing amount of the end surface 2 of the glass plate 1 can be kept constant in the transport direction. In addition, in the glass plate which concerns on this invention, its end surface processing method, and a manufacturing method, you may use the end surface processing apparatus (illustration omitted) of another system.

  Then, the end surface processing method and manufacturing method of a glass plate in the case of using the end surface processing apparatus 10 mentioned above are demonstrated.

  The manufacturing method which concerns on this embodiment prepares the glass plate 1, and processes the end surface 2 of the prepared glass plate 1 with the end surface processing method mentioned later. In preparation of the glass plate 1, for example, a forming original plate is obtained by a downdraw method or the like, and the glass plate 1 is cut out from the forming original plate. If necessary, the glass plate 1 after end face processing is inspected and packed.

  The end face processing method according to the present embodiment includes a preparation step S1 for preparing the subassembly 25 of the grindstone 11 (12) and the grindstone mounting flange 20 so as to have a predetermined static runout and dynamic balance, and the end face machining described above. A rotation speed selection step S2 for selecting the rotation speed of the grindstone 11 (12) at the time, and an end face machining process S3 for performing the above-described end face machining using the selected rotation speed.

(S1) Preparation Step In this step, a subassembly 25 of the grindstone 11 (12) and the grindstone mounting flange 20 having a static runout of 40 μm or less and a dynamic balance of 50 g · mm or less is prepared. Here, the static runout of the subassembly 25 is preferably 20 μm or less, more preferably 15 μm or less, and most preferably 10 μm or less. Further, the dynamic balance of the subassembly 25 is preferably 40 g · mm or less, and more preferably 30 g · mm or less. On the other hand, from the viewpoint of manufacturing cost and work efficiency, the static runout of the subassembly 25 is preferably 5 μm or more, and the dynamic balance of the subassembly 25 is preferably 10 g · mm or more.

  The dynamic balance can be measured using a predetermined dynamic balance measuring device. The dynamic balance may be adjusted within the above numerical range by, for example, cutting an appropriate part or attaching a weight to an appropriate part. Here, if the grindstone 11 (12) in which the dynamic balance is 20 g · mm or less and the grindstone mounting flange 20 in which the dynamic balance is 20 g · mm or less are used, the static touch is adjusted to 40 μm or less. The dynamic balance of the subassembly 25 naturally falls within the above numerical range. For this reason, by preparing the grindstone 11 (12) having a dynamic balance of 20 g · mm or less and the grindstone mounting flange 20 having a dynamic balance of 20 g · mm or less, the dynamic balance of the subassembly 25 falls within the above numerical range. You may adjust it.

The adjustment of the static touch of the subassembly 25 can be performed by the following procedure, for example.
(Procedure 1) The subassembly 25 is mounted on a rotating body (not shown) that simulates the spindle 19 of the end face processing apparatus 10.
(Procedure 2) The subassembly 25 is rotated together with the rotating body in a state where the dial gauge probe is pressed against the metal surface on the outer periphery of the grindstone 11 (12). The static touch of the subassembly 25 is measured by reading the change amount (difference between the maximum value and the minimum value) of the dial gauge at that time.
(Procedure 3) The position of the grindstone 11 (12) with respect to the rotating body or the grindstone mounting flange 20 is slightly moved by tapping with a hammer or the like, and the static touch of the subassembly 25 is adjusted within the above numerical range.

(S2) Rotation Speed Selection Step In this step, end face processing (test processing) is performed with the subassembly 25 attached to the spindle 19 of the end face processing apparatus 10. At this time, the rotational speed is changed while measuring the vibration in the direction orthogonal to the rotational axis Y of the spindle 19 (see FIG. 2), and the rotational speed at which the vibration amplitude is 50 μm or less is selected. At that time, it is preferable to select a rotation speed at which the amplitude of vibration is 30 μm or less. When measuring this vibration, it is preferable to measure the vibration (component) in the direction along the normal direction of the end face 2 of the glass plate 1.

(S3) End surface processing step In this step, the subassembly 25 prepared in the preparation step S1 is attached to, for example, the spindle 19 (see FIG. 2) of the end surface processing apparatus 10 shown in FIG. Predetermined end face processing (grinding and polishing) is performed. At this time, the rotation speed selected in the rotation speed selection step S <b> 2 is used for the motor 13 to perform the predetermined end face processing on the end face 2. Here, FIG. 3 shows an example of the waviness curve of the end face 2 of the glass plate 1 obtained by the end face processing method other than the present invention, and FIG. 4 shows the end face of the glass plate 1 obtained by the end face processing method according to the present invention. An example of two waviness curves is shown. As shown in FIG. 3, when a predetermined end surface processing is performed on the end surface 2 of the glass plate 1 by an end surface processing method other than the present invention, specifically, the static runout exceeds 40 μm or the dynamic balance is 50 g · mm. When the end surface processing was performed using the sub-assembly 25 exceeding 1, the waviness curve of the obtained end surface 2 showed a minute waviness in which the level difference between the peak portion and the valley portion was recognized to a considerable extent. On the other hand, when the end face processing according to the present invention is performed, specifically, when the end face processing is performed using the subassembly 25 in which the static runout is 40 μm or less and the dynamic balance is 50 g · mm or less. In the obtained undulation curve of the end face 2, almost no undulation was observed (it was almost flat).

  Further, the arithmetic average waviness Wa of the end face 2 obtained by the end face processing method according to the present invention was less than 2.7 μm. Further, the arithmetic average roughness Ra of the end face 2 at that time was 1.2 μm or less, and the protruding valley depth Rvk was 2.5 μm or less. The arithmetic average waviness Wa of the end face 2 is preferably 2.6 μm or less, more preferably 2.5 μm or less, and the lower limit is preferably 1.0 μm or more. The arithmetic average roughness Ra of the end face 2 is more preferably 1.0 μm or less, and the lower limit is preferably 0.3 μm or more. The protrusion valley depth Rvk is more preferably 2.0 μm or less, and the lower limit is preferably 1.0 μm or more.

  In the present invention, the arithmetic average waviness Wa, the arithmetic average roughness Ra, and the protruding valley depth Rvk of the end face 2 are measured according to JIS B 0601: 2013. Moreover, in the measurement of arithmetic mean wave | undulation Wa, arithmetic mean roughness Ra, and protrusion trough part depth Rvk, it measures at ten places of equal intervals along one side of a glass plate about the end surface of a glass plate. The arithmetic average waviness Wa uses the average value of 10 measurement results, and the arithmetic average roughness Ra and the protruding valley depth Rvk use the maximum values of the 10 measurement results.

  As described above, in the present invention, the grindstone 11 (12) having a static runout of 40 μm or less and a dynamic balance of 50 g · mm or less and the subassembly 25 of the grindstone mounting flange 20 are prepared. 19 is applied to the end face 2 of the glass plate 1 so as to perform predetermined end face processing (grinding and polishing), for example, the fine waviness shown in FIG. 3 can be stably eliminated or reduced. Thereby, since it can grind | polish without omission over the whole area of the end surface 2, it becomes possible to improve the surface roughness of the end surface 2 (the value of surface roughness Ra is made small). Of course, by suppressing the dynamic balance of the subassembly 25 to a predetermined value or less, the accuracy of the polishing process can be increased, and this also makes it possible to effectively improve the surface roughness Ra.

  As mentioned above, although one Embodiment of this invention was described, of course, the glass plate which concerns on this invention, the end surface processing method of a glass plate, and a manufacturing method are not limited to this form, Various forms are within the scope of this invention. It is possible to take.

  For example, in the above embodiment, the sub-assembly 25 of the grindstone 11 (12) and the grindstone mounting flange 20 having a static runout of 40 μm or less and a dynamic balance of 50 g · mm or less is used, and FIGS. The case where the glass plate 1 in which the arithmetic average waviness Wa of the end surface 2 is less than 2.7 μm is obtained by performing the end surface processing shown in FIG. May be manufactured. For example, the glass plate 1 in which the arithmetic average waviness Wa of the end surface 2 is less than 2.7 μm is obtained by performing the above-described end surface processing while suppressing the vibration generated in the grindstones 11 and 12 by means other than adjustment of the dynamic balance. be able to.

  Moreover, in the said embodiment, although the case where two types of grindstones 11 and 12 from which a particle size differs was arrange | positioned 1 each at the position which opposes on both sides of the glass plate 1, of course, other arrangement | positioning aspects may be taken. Is possible. For example, it is also possible to arrange the grindstones 11 and 12 at two or three pairs or more at positions facing each other with the glass plate 1 in between. Moreover, as long as the required quality including the shape can be ensured for the end surface 2 after the end surface processing, for example, one set or a plurality of sets of the grindstones 11 (12) of one shape are arranged at positions facing each other with the glass plate 1 interposed therebetween. It is also possible to do.

  Moreover, in the said embodiment, the end surface processing method called what is called a constant pressure type which processes the end surface 2 in the state which maintained the contact pressure (pressing force) of the grindstone 11 (12) and the end surface 2 at a fixed magnitude | size is illustrated. However, when adopting an end face processing method called a so-called fixed type in which the end face 2 is processed in a state where the position of the grindstone 11 (12) in the width direction (direction orthogonal to the feed direction X) of the glass plate 1 is fixed. In addition, the present invention can be applied.

  Hereinafter, the operation and effect of the present invention will be described based on examples.

<Production of glass plate>
A glass plate having a size of 2200 mm × 2500 mm and a thickness of 0.5 mm was cut out by folding, and the end surface processing was performed on the end surface of the long side of the glass plate by the end surface processing apparatus 10 of the method shown in FIG. In the end face processing, one set of the first grindstone 11 for grinding was arranged and one set of the second grindstone 12 for polishing was arranged. The rotational speed of the grindstone 11 (12) was both 5000 rpm, and the conveyance speed (feed speed) of the glass plate 1 was 20 m / min.

  The sub-assembly of the grinding wheel and the flange for mounting the grinding wheel has a static touch of 30 μm and a dynamic balance of 10 g · mm, a static touch of 30 μm and a dynamic balance of 30 g · mm, or a static touch The one having 30 μm and a dynamic balance of 60 g · mm was used.

<Measurement of end face properties>
Arithmetic mean waviness Wa, arithmetic mean roughness Ra, and protruding valley depth Rvk were measured on the long side end face of the glass plate after end face processing. The measurement was performed according to JIS B 0601: 2013 using a surface roughness measuring machine (Surfcom) manufactured by Tokyo Seimitsu Co., Ltd. Moreover, about the end surface of the long side of a glass plate, it measured in ten places of equal intervals. For the arithmetic average waviness Wa, an average value of 10 measurement results was used, and for the arithmetic average roughness Ra and the protrusion valley depth Rvk, the maximum value of 10 measurement results was used.

<Measurement results>
The measurement results are shown in FIGS. As shown in FIG. 5, when the dynamic balance of the subassembly of the grindstone and the grindstone mounting flange is 50 g · mm or less (in the case of 10 g · mm or 30 g · mm), the arithmetic average waviness Wa (average value) of the end face is The value was less than 2.7 μm. On the other hand, when the dynamic balance exceeded 50 g · mm (in the case of 60 g · mm), the arithmetic average waviness Wa (average value) showed a value exceeding 2.7 μm.

  As shown in FIG. 6, when the dynamic balance of the sub-assembly of the grindstone and the grindstone mounting flange is 50 g · mm or less (in the case of 10 g · mm or 30 g · mm), the arithmetic average roughness Ra of the end face is the highest. Even a large value showed a value of less than 1.2 μm. On the other hand, when the dynamic balance exceeded 50 g · mm (in the case of 60 g · mm), the maximum value of the arithmetic average roughness Ra showed a value exceeding 1.2 μm. Thus, when the average value of the arithmetic average waviness Wa of the end face was less than 2.7 μm, it was found that the maximum value of the arithmetic average roughness Ra was less than 1.2 μm.

  At this time, as shown in FIG. 7, when the dynamic balance of the sub-assembly of the grindstone and the grindstone mounting flange is 50 g · mm or less (in the case of 10 g · mm or 30 g · mm), the protruding valley depth of the end face Rvk was less than 2.5 μm even at the largest value. On the other hand, when the dynamic balance exceeded 50 g · mm (in the case of 60 g · mm), the maximum value of the protruding valley depth Rvk showed a value exceeding 2.5 μm.

DESCRIPTION OF SYMBOLS 1 Glass plate 2 End surface 10 End surface processing apparatus 11, 12 Grinding wheel 13 Motor 14 Arm member 15 Servo mechanism 16 Support shaft member 17 Servo motor 17a Rotating shaft 18 Link mechanism 18a First link member 18b Second link member 18c First joint 18d Second joint 19 Spindle 20 Wheel mounting flange 21 Fitting hole 22 Fitting convex portion 23 Fitting concave portion 24 Tip portion 25 Subassembly S1 Preparatory step S2 Speed selection step S3 End face processing step

Claims (8)

A grindstone is attached to a spindle driven by a motor via a grindstone mounting flange, and the grindstone is brought into contact with the end face of the glass plate while rotating the grindstone by the rotation of the spindle. An end face processing method for a glass plate,
A preparatory step in which a sub-assembly of the grindstone and the grindstone mounting flange is prepared such that a static runout is 40 μm or less and a dynamic balance is 50 g · mm or less;
An end surface processing method for attaching a glass plate to the end surface of the glass plate, wherein the subassembly is attached to the spindle and the end surface of the glass plate is subjected to the predetermined processing.   2. The method for processing an end face of a glass plate according to claim 1, wherein in the preparation step, the grinding wheel mounting flange having a dynamic balance of 20 g · mm or less and the grinding wheel having a dynamic balance of 20 g · mm or less are prepared. With the subassembly attached to the spindle, the rotational speed is changed while measuring the vibration in the direction perpendicular to the rotation axis of the spindle, and the rotational speed is selected so that the amplitude of the vibration is 50 μm or less. A further process,
The end face processing method of the glass plate of Claim 1 or 2 which performs the predetermined process to the said end surface using the said selected rotation speed in the said end surface processing process.   The end face processing of the glass plate according to any one of claims 1 to 3, wherein in the end face processing step, the end face is processed in a state where a contact pressure between the grindstone and the end face is maintained at a constant magnitude. Method. A method of manufacturing a glass plate,
Preparing a glass plate;
A method for manufacturing a glass plate, comprising: a step of processing the end surface of the glass plate prepared by the method for processing an end surface of a glass plate according to any one of claims 1 to 4. A glass plate in a state in which a predetermined processing with a grindstone has been applied to the end face,
The glass plate whose arithmetic mean wave | undulation Wa of the said end surface is less than 2.7 micrometers.   The glass plate according to claim 6, wherein the arithmetic mean roughness Ra of the end face is 1.2 μm or less.   The glass plate according to claim 6 or 7, wherein a protruding valley depth Rvk of the end face is 2.5 µm or less.