JP6973237B2 - How to manufacture flat glass - Google Patents

Description

The present invention relates to a method for manufacturing a flat glass, which comprises a step of processing the end face of the flat glass.

In recent years, in order to improve the manufacturing efficiency of liquid crystal displays, organic EL displays and the like, and to meet the demand for upsizing, the size of the flat glass used for these tends to be increased. If the size of the plate glass is increased, the number of glass substrates that can be taken from one plate glass increases, and it becomes possible to efficiently manufacture a glass substrate compatible with a large display. Further, in order to increase the processing quantity per hour and reduce the manufacturing cost, it is considered to increase the processing speed (processing speed) of the flat glass.

If there is a scratch on the end face of the plate glass, cracks or the like occur from the scratch, and in order to prevent this, the end face of the plate glass is ground and polished. There are two types of end face processing equipment for flat glass: a constant pressure type that keeps the pressing force of the processing tool constant, and a fixed type that fixes the processing tool for processing. In order to process the end face of the plate glass to be uniform with the fixed end face processing device for the shape of the plate glass cut in the upstream process, it is necessary to set a large grinding / polishing allowance for the plate glass. Therefore, the processing time becomes long, and it is difficult to further increase the transport speed (machining speed) of the flat glass.

As a technique for processing the end face of a plate glass by a constant pressure method, Patent Document 1 describes a processing tool for processing the end face of the plate glass, a pressing force generating element for urging the processing tool to the end face of the plate glass to generate a pressing force. A flat glass processing apparatus including a measuring means for measuring the position of a processing tool is disclosed. The processing tool includes a grindstone and an arm member that supports the grindstone. The pressing force generating element applies a couple to the arm member of the processing tool and urges the processing tool to the end face of the plate glass to generate the pressing force. The plate glass processing apparatus processes the end face of the plate glass at high speed and with high accuracy by controlling the pressing force generating element so that the pressing force becomes constant.

This plate glass processing device controls the processing tool to move to a reference position as an initial position at the start of processing and a standby position where the processing tool is separated from the plate glass and stands by after the processing is completed. At the start of machining, the flat glass processing device moves the machining tool from the standby position to the reference position, and starts controlling the pressing force by the pressing force generating element. At this time, when the processing tool is separated from the plate glass, the pressing force generating element moves the processing tool so as to come into contact with the end face of the plate glass.

A grindstone is used as a processing tool for processing the end face of the plate glass, and the grindstone has a groove portion for receiving the end portion of the plate glass.

Japanese Unexamined Patent Publication No. 2014-161981

As a plurality of flat glass sheets are machined, the groove portion of the processing tool gradually wears and its depth increases. It is conceivable to change the reference position for each plate glass in order to cope with the wear of the groove portion of the processing tool, for example, to correct the reference position by moving it by a certain distance in the direction approaching the end face of the plate glass. However, since the degree of wear of the groove portion of the processing tool varies, the correction (movement) of the reference position may be insufficient or excessive. If the correction of the reference position is insufficient, the machining tool needs to move from the reference position toward the end face of the plate glass at the start of machining. If the amount of movement of the processing tool becomes large, the processing tool comes into contact with the end face of the plate glass in a state where the pressing force is insufficient at the initial stage of processing, so that there is a possibility that a part of the end surface of the plate glass may be unprocessed or insufficiently processed. There is. Further, when the correction of the reference position is excessive, the machining tool comes into contact with the plate glass with an excessive pressing force at the start of processing, and moves in a direction away from the end face of the plate glass. If the amount of movement of this processing tool is large, there is a possibility that problems such as burning of the groove may occur due to the impact at the time of contact.

The present invention has been made in view of the above circumstances, and when the end face of a plate glass is processed by a constant pressure type processing tool, the production of a plate glass capable of suitably controlling the position of the processing tool at the start of processing. The purpose is to provide a method.

The present invention is for solving the above-mentioned problems, and in a method for manufacturing a plate glass including an end face processing step of processing an end face of the plate glass with a processing tool, the processing tool is in an approaching direction or a separation direction with respect to the end face. It is a constant pressure type machining tool that is movable to the end face and comes into contact with the end face at a constant pressure. The end face machining step includes a position control step in which the position of the machining tool is controlled by a control device. The position control step includes a preparatory step of arranging the machining tool at a reference position before the start of machining and before the machining tool comes into contact with the end face, and a preparatory step of placing the machining tool on the end face at the start of machining. A measurement step of measuring the movement amount of the machining tool in the approaching direction or the separating direction at the time of contact, and a correction step of setting the reference position of the machining tool to be related to the next machining based on the moving amount. It is characterized by having.

As described above, the machining tool is set to the reference position by the control of the control device in the preparation process. The reference position is a position in the cutting direction of the machining tool at the start of machining in the end face machining process, and is set (adjusted) so that the end face of the flat glass can be machined at a desired pressure, for example. In the present invention, the reference position is also used as the initial position for measuring the position of the processing tool in the cutting direction.

At the start of machining, the machining tool moves from the reference position in the direction of approaching the plate glass (approaching direction) or in the direction of separation opposite to the approaching direction, depending on the degree of wear of the groove. In the present invention, the movement amount is measured by the control device in the measurement step, and the reference position for the next machining is set based on the movement amount in the correction step. As a result, the reference position, which is the initial position of the machining tool at the start of machining, can be suitably controlled according to the change in the positional relationship between the machining tool and the flat glass due to the influence of the wear of the machining tool. Therefore, it is possible to prevent the occurrence of processing defects on the end face of the flat glass and to extend the life of the processing tool.

In the present invention, the "movement amount when the processing tool comes into contact with the end face of the plate glass" is defined as the approaching direction or the separation direction between the reference position and the contact of the processing tool with the end face of the plate glass at a desired pressure. It means the distance traveled.

The position control step further includes a determination step of determining whether or not the movement amount exceeds the threshold value, and the correction step is executed when it is determined in the determination step that the movement amount exceeds the threshold value. You may. By setting the threshold value for the movement amount in this way, it is possible to absorb the variation in the movement amount due to the positioning accuracy of the alignment. Therefore, even when the alignment accuracy is low, the reference position, which is the initial position of the machining tool at the start of machining, can be suitably controlled according to the change in the positional relationship between the machining tool and the flat glass due to the influence of wear of the machining tool. ..

In the correction step, a correction value for setting the reference position of the processing tool in the next machining is calculated based on the movement amount, and the correction value can be calculated by the following formula (1).
CV = CF × X ・ ・ ・ (1)

Here, CV is a correction value, CF is a correction factor, and X is a movement amount.

By setting the reference position according to the correction value calculated by the equation (1) in this way, the reference position can be controlled more preferably.

In the correction step, the correction factor when the movement amount indicates the movement of the processing tool in the separation direction is smaller than the correction factor when the movement amount indicates the movement of the processing tool in the approaching direction. It is desirable to set.

When the machining tool tends to be separated from the end face of the flat glass at the start of machining, the machining tool is brought as close as possible to the end face of the flat glass by setting a large correction factor and determining the next reference position. Processing can be started in the state. On the other hand, when the machining tool tends to move in the separation direction at the start of machining, if the reference position is set so that the machining tool is greatly separated from the end face in the next machining, the machining tool comes into contact with the end face at the start of machining. However, there is a risk that unprocessed parts will remain on the flat glass. As described above, by setting the correction factor of the machining tool related to the separation direction to be smaller than the correction factor of the machining tool related to the approaching direction, it is possible to prevent the unprocessed portion from remaining.

In the measurement step, when the plurality of the plate glasses are processed, the movement amount is measured for each of the plate glasses, and in the correction step, the average value of the movement amounts of the plurality of the plate glasses may be used as the movement amount. desirable. In this way, by referring to the average value of the amount of movement measured in the machining of a plurality of flat glass, the reference position for the next machining can be set with high accuracy so as to adapt to the past tendency of flat glass machining. ..

Further, the processing tool is a grindstone having a plurality of grooves for processing the end face, and it is desirable that the control device sets the reference position for each of the grooves. According to such a configuration, even if the degree of wear of each groove portion is different, for example, the reference position of the processing tool in the next machining can be suitably set for each groove portion by the correction step.

According to the present invention, when the end face of the flat glass is machined by a constant pressure type machining tool, the position of the machining tool at the start of machining can be suitably controlled.

It is a schematic plan view which shows the manufacturing apparatus of a plate glass. It is a side view of an unused processing tool. It is a top view which shows the cutting process. It is a flowchart of a position control process. It is a top view which shows the end face processing process. It is an enlarged plan view which shows the main part of FIG. It is a graph which shows the position of the processing tool at the start of processing which concerns on FIG. It is a table which shows the history data which concerns on the movement amount of a processing tool. It is a top view which shows the end face processing process. It is an enlarged plan view which shows the main part of FIG. It is a graph which shows the position of the processing tool at the start of processing which concerns on FIG. It is a side view which shows the processing tool in the state where the wear of a groove portion has progressed.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. 1 to 12 show an embodiment of a method for manufacturing a flat glass according to the present invention.

The plate glass G produced by this method has a rectangular plate shape, but is not limited to this shape. The plate thickness of the plate glass G is, for example, 0.05 mm to 10 mm, but is not limited to this range, and is appropriately set according to conditions such as the material and size of the plate glass G.

As the material of the plate glass G, silicate glass and silica glass are used, preferably borosilicate glass, soda lime glass, aluminosilicate glass, and chemically strengthened glass, and most preferably non-alkali glass is used. Here, the non-alkali glass is a glass that does not substantially contain an alkaline component (alkali metal oxide), and specifically, a glass having a weight ratio of an alkaline component of 3000 ppm or less. be. The weight ratio of the alkaline component in the present invention is preferably 1000 ppm or less, more preferably 500 ppm or less, and most preferably 300 ppm or less.

FIG. 1 illustrates a flat glass processing apparatus used in this method. The plate glass processing device 1 includes a processing tool 2, a pressing force generating element 3, a measuring unit 4, and a control device 5.

The processing tool 2 is a rotary tool that processes the end face ES of the plate glass G from the processing start end portion C1 which is one end portion to the machining end portion C2 which is the other end portion. The processing tool 2 grinds and / or polishes the end face ES of the plate glass G. At the same time, the processing tool 2 may be used for chamfering the end face ES of the flat glass G.

The processing tool 2 is provided so as to be movable relative to the plate glass G along the end face ES of the plate glass G. In the present embodiment, an example is shown in which the processing tool 2 performs processing while moving along the moving direction F with respect to the end face ES of the stopped flat glass G, but the present invention is not limited to this, and is opposite to the moving direction F. The processing tool 2 in a fixed position may process the end face ES of the plate glass G moving in the direction.

The processing tool 2 has a grindstone 6 and an arm member 7 that supports the grindstone 6. The grindstone 6 is a cylindrical or truncated cone-shaped disk member that grinds the end face ES of the plate glass G while rotating. The grindstone 6 is supported by the arm member 7 so that the disk surface 6A is parallel to the main surface Ga of the plate glass G. The grindstone 6 is rotationally driven by a drive motor. The drive motor is connected to the control device 5. As the grindstone for grinding, for example, an electrodeposition grindstone in which diamond abrasive grains are hardened with a metal electrodeposition bond and a metal bond grindstone in which the abrasive grains are hardened with a metallic binder are preferably used. As the grindstone for polishing, for example, a resin bond grindstone obtained by mixing SiC abrasive grains with a binder such as a resin bond containing a curable resin as a main component and firing this mixture is preferably used.

As shown in FIG. 2, the grindstone 6 has a plurality of groove portions 6a for processing the end face ES of the plate glass G. In the case of the grindstone 6 in an unused state, the depths of the groove portions 6a are equal. Each groove 6a may be composed of bonds having the same particle size and the same type, or may be composed of bonds having different particle sizes and different types.

One end of the arm member 7 is rotatably pivotally supported, and the other end rotatably supports the grindstone 6. The arm member 7 has a bent shape in which the ends of the two members 7a and 7b are connected. However, the present invention is not limited to this, and the arm member 7 may be composed of an integral member and have a linear shape.

The arm member 7 causes the grindstone 6 to approach the end face ES of the plate glass G or to separate from the end face ES by its rotational operation. As a result, the grindstone 6 is configured to be movable in the approaching direction CDa approaching the end face ES of the plate glass G and the separation direction CDb moving away from the plate glass G. Hereinafter, the approaching direction CDa and the separating direction CDb of the plate glass G are collectively referred to as a cutting direction CD.

The processing tool 2 is controlled to move to two locations, the reference position RP and the standby position SP. The reference position RP is an initial position set for measuring the position of the processing tool 2 in the cutting direction CD in the end face processing process. The standby position SP is a position where the processed tool 2 stands by away from the flat glass G.

The plate glass processing apparatus 1 may further include an arm position control unit 8. The arm position control unit 8 controls the position of the arm member 7 so that the machining tool 2 moves to two positions, the standby position SP and the reference position RP. When the machining tool 2 moves from the standby position SP to the reference position RP, moves from the reference position RP to the standby position SP, and is located at the standby position SP, the arm member 7 is controlled by the arm position control unit 8. It is locked and does not move freely. On the other hand, when the processing tool 2 is located at the reference position RP, the control by the arm position control unit 8 does not work and the lock is released, and the arm member 7 is arm-free.

The pressing force generating element 3 urges the processing tool 2 to the end face ES of the plate glass G to generate the pressing force. For example, the pressing force generating element 3 urges the processing tool 2 to the end face ES of the plate glass G by applying a couple to the arm member 7. In the present embodiment, the pressing force generating element 3 applies a couple to the arm member 7 at the timing when the end face ES of the plate glass G and the grindstone 6 of the processing tool 2 moved to the reference position RP come into contact with each other. In the reference position RP, since the arm member 7 is arm-free, the processing tool 2 is urged to the end face ES by a couple.

The pressing force generating element 3 may be a low sliding resistance air cylinder. In the present embodiment, a diaphragm cylinder can be used as a low sliding resistance air cylinder in consideration of high speed response due to low sliding property and long life due to pistonless operation. The pressing force generating element 3 is not limited to an air cylinder, and a hydraulic cylinder, other well-known driving device, or a member capable of generating pressing force such as a spring or a weight may be used. The processing tool 2 is a constant pressure type processing tool in which the pressing force is feedback-controlled by the pressing force generating element 3 so that the pressing force on the plate glass G becomes constant. Since such a constant pressure type processing tool imitates the undulation of the end face ES of the plate glass G, the end face ES of the plate glass G can be processed with a substantially constant cutting amount.

The processing tool 2 is integrated with the pressing force generating element 3, the measuring unit 4, and the arm position control unit 8 to form the processing unit U. The processing unit U is configured to be movable by a moving mechanism. That is, the machining unit U moves the machining tool 2 along the moving direction F or moves it to the cutting direction CD via the moving mechanism.

The measuring unit 4 measures the distance between the processing tool 2 and the measuring unit 4. The measuring unit 4 is a displacement sensor such as an optical type, an eddy current type, or an ultrasonic type. In this embodiment, an eddy current type displacement sensor is used as the measuring unit 4. As shown in FIG. 1, the measuring unit 4 is arranged at a position on the same side as the pressing force generating element 3 and the arm position control unit 8 with respect to the arm member 7 and at a position separated from the arm member 7 by a predetermined distance. Then, the measuring unit 4 measures the distance from the measuring unit 4 to the arm member 7 as the position information of the processing tool 2. The measuring unit 4 is connected to the control device 5 and transmits the measured data to the control device 5.

The control device 5 includes a computer (for example, a PC) that implements various hardware such as a CPU, ROM, RAM, HDD, and input / output interface. The control device 5 includes a calculation processing unit 9 that executes various calculations, and a storage unit 10 that stores data and various programs necessary for processing the flat glass G. The control device 5 is connected to the display device 11, and causes the display device 11 to display information related to the processing of the flat glass G. Further, the control device 5 is connected to a drive motor that rotates the grindstone 6 of the processing tool 2, and controls the drive motor.

The control device 5 executes various data and various programs stored in the storage unit 10 by the arithmetic processing unit 9, and executes a program necessary for controlling the pressing force generating element 3 and the processing unit U. The control device 5 causes the display device 11 to display the position information (numerical value) of the processing tool 2 received from the measuring unit 4.

The arithmetic processing unit 9 can calculate the movement amount D of the machining tool 2 at the start of machining from the position information of the machining tool 2. The arithmetic processing unit 9 includes a determination unit 12 that compares the movement amount D with the threshold values TH1 and TH2.

The storage unit 10 stores various programs for controlling the pressing force generating element 3, the arm position control unit 8, the moving mechanism of the processing unit U, and the like, in addition to the position information of the processing tool 2 acquired by the measuring unit 4. ing. The storage unit 10 stores a program (software) related to the correction of the reference position RP. Further, the storage unit 10 stores the threshold values TH1 and TH2 related to the movement amount D of the processing tool 2. The values of the threshold values TH1 and TH2 can be arbitrarily set in the control device 5.

Hereinafter, a method for manufacturing the plate glass G using the plate glass processing apparatus 1 having the above configuration will be described. The method for manufacturing the flat glass G mainly includes a cutting step and an end face processing step. If necessary, a cleaning step is provided as a post-process of the end face processing step.

As the plate glass MG supplied to the cutting step, plate glass obtained by cutting a glass ribbon formed by various known molding methods can be used. As various known molding methods, for example, a float method, a rollout method, an overflow downdraw method, a slot downdraw method, a redraw method and the like can be adopted. When the overflow down draw method is adopted, for example, molten glass is poured into an overflow groove provided in the upper part of a molded body having a substantially wedge-shaped cross section, and the molten glass overflowing from the overflow groove on both sides is applied to both sides of the molded body. While flowing down along the side wall portion, the glass ribbon is continuously molded by being fused and integrated at the lower end portion of the molded body.

The formed glass ribbon is slowly cooled in a slow cooling furnace to remove the strain, and then the glass ribbon is cooled. The cooled glass ribbon is cut to a predetermined length, and both ends in the width direction are removed by cutting. As a result, a flat glass MG is obtained.

The flat glass MG supplied in the cutting step is cut into flat glass of a desired size by cutting. In the cutting step, one or a plurality of flat glass sheets are cut out from the flat glass plate MG. As a result, the plate glass G to be processed by the plate glass processing apparatus 1 can be obtained. The cutting of the flat glass MG is performed by, for example, scribe cutting.

Hereinafter, scribe cutting will be described with reference to FIG. First, the scribe wheel SH is run along the planned cutting line CL of the large flat glass MG. As a result, a scribe line having a predetermined depth is engraved on the flat glass MG along the planned cutting line CL. Then, a bending moment is applied around the scribe line to break the flat glass MG along the scribe line. By this folding, a plurality of flat glass G can be obtained.

After that, the end face processing step of the plate glass processing apparatus 1 shown in FIG. 1 is performed on the plate glass G. The end face processing step includes a step of grinding the end face ES of the plate glass G (grinding step) and a step of polishing the end face ES after the grinding step (polishing step). In the grinding step and the polishing step, the position control step of the grindstone 6 by the pressing force generating element 3, the measuring unit 4, the control device 5, and the arm position control unit 8 is executed.

Hereinafter, the outline of the end face processing process will be described. The flat glass G formed through the cutting step is conveyed to a processing position in the end face processing process by a conveyor (conveyor) (not shown). After arranging the plate glass G at the processing position, the conveyor temporarily stops until the end face processing is completed. Further, the plate glass G arranged at the processing position is held on a surface plate (not shown).

When the flat glass G is installed, the processing unit U starts moving along the moving direction F. When approaching the flat glass G, the grindstone 6 of the processing tool 2 moves from the standby position SP to the reference position RP under the control of the arm position control unit 8. The pressing force generating element 3 urges the arm member 7 at the timing when the grindstone 6 of the machining tool 2 comes into contact with the machining start end portion C1. Due to this urging, the grindstone 6 comes into contact with the end face ES of the plate glass G with a constant pressing force.

Then, the machining tool 2 performs grinding processing on the end face ES from the machining start portion C1 to the machining end portion C2. During this time, the pressing force generating element 3 continues to urge the arm member 7. In this example, under the control of the machining unit U by the control device 5, the grindstone 6 of the machining tool 2 is in contact with the end face ES of the plate glass G, from the machining start end portion C1 on the long side of the plate glass G to the machining end portion C2. Move across.

After that, the pressing force generating element 3 stops urging at the timing when the grindstone 6 separates from the end face ES of the plate glass G, and the processing tool 2 returns to the standby position SP under the control of the arm position control unit 8. The processing tool 2 may be moved so as to process a part of the end face ES of the plate glass G. When the processing of the end face ES is completed, the surface plate releases the holding of the plate glass G, and the conveyor conveys the plate glass G to the next process.

Next, the details of the position control step at the start of machining of the end face machining step will be described with reference to FIGS. 4 to 11. As shown in FIG. 4, the position control step includes a preparation step S1 for arranging the machining tool 2 at the reference position RP and a measuring unit 4 before the machining tool 2 comes into contact with the end face ES of the plate glass G before the start of machining. A measurement step S2 by the control device 5, a determination step S3 by the determination unit 12, and a correction step S4 by the control device 5 are mainly provided.

5 to 8 show a control mode when the processing tool 2 installed at the reference position RP moves in the approaching direction CDa.

As shown in FIGS. 5 and 6, in the preparation step S1, when the processing tool 2 moving along the moving direction F reaches the vicinity of the plate glass G, the standby position SP (FIG. 5) is controlled by the arm position control unit 8. The processing tool 2 at the position indicated by the alternate long and short dash line) is moved to the CDa in the approaching direction. As a result, the processing tool 2 is installed at the reference position RP (position shown by a solid line in FIGS. 5 and 6). When the machining tool 2 is installed at the reference position RP, the pressing force generating element 3 starts the constant pressure control of the machining tool 2 as described above.

As shown in FIGS. 5 to 7, when the groove portion 6a of the processing tool 2 arranged at the reference position RP is separated from the end face ES of the plate glass G, the pressing force generating element 3 pushes the arm member 7 and the processing tool 2 is used. Is moved in the approaching direction CDa.

When the processing tool 2 comes into contact with the end face ES of the plate glass G, processing of the plate glass G starts. The pressing force generating element 3 detects this contact and adjusts the pressure on the arm member 7 so that the pressing force of the processing tool 2 becomes constant.

The control device 5 stores the position information of the grindstone 6 in the storage unit 10, and causes the display device 11 to display the temporal change related to the position information of the grindstone 6 as a graph. FIG. 7 shows a graph showing the position information of the grindstone 6 at the start of machining. In FIG. 7, the reference position RP is displayed as 0. Further, when the grindstone 6 is located on the CDa side in the approaching direction with respect to the reference position RP, this position is displayed as a positive (+) value. On the other hand, when the grindstone 6 is on the CDb side in the direction away from the reference position RP, this position is displayed as a negative (−) value.

In the present embodiment, as described above, the position of the processing tool 2 on the CDa side in the approaching direction from the reference position RP is set as a positive (+) value, and the processing tool 2 on the CDb side in the separation direction from the reference position RP is set. The position is set to a negative (−) value, but this positive / negative value is set to simply distinguish between the movement of the approaching direction CDa and the movement of the separation direction CDb related to the grindstone 6. Therefore, contrary to the above, it is also possible to set the position information on the CDb side in the separation direction to be positive (+) and the position information on the CDa side in the approach direction to be negative (−).

In the measuring step S2, the measuring unit 4 measures the position of the processing tool 2 (distance between the processing tool 2 and the measuring unit 4) and transmits the position information to the control device 5. The arithmetic processing unit 9 of the control device 5 is the distance from the reference position RP to the contact of the end face ES of the plate glass G, that is, positive (+), based on the position information of the processing tool 2 received from the measuring unit 4. ) The movement amount D is calculated.

In the determination step S3, the determination unit 12 of the arithmetic processing unit 9 compares the calculated movement amount D of the processing tool 2 with the positive (+) threshold value TH1. When the movement amount D exceeds the threshold value TH1, the arithmetic processing unit 9 updates the reference position RP of the processing tool 2 related to the next processing. That is, the arithmetic processing unit 9 determines the reference position RP of the machining tool 2 in the next machining based on the movement amount D of the machining tool 2 obtained by the calculation.

The reference position RP of the processing tool 2 related to the next processing is determined based on the following formula (1).
CV = CF × X ・ ・ ・ (1)

Here, CV is a correction value related to the reference position RP, CF is a correction factor related to the reference position RP, and X is the measured movement amount D (mm) of the processing tool 2.

The correction value CV is a positive or negative numerical value (mm) added to the reference position RP set before the next machining. The correction factor CF is, for example, a numerical value (%) arbitrarily set between 0 and 1.

When the processing tool 2 tends to be separated from the end face ES of the plate glass G at the start of processing, it is desirable to set a large correction factor CF to calculate the correction value CV. As a result, the processing tool 2 installed at the reference position RP in the next processing is in a state as close as possible to the end face ES of the plate glass G.

On the other hand, when the machining tool 2 tends to move to the CDb in the separation direction at the start of machining, if the reference position RP is set so that the machining tool 2 is largely separated from the end face ES in the next machining, the machining tool 2 will move at the start of machining. There is a possibility that an unprocessed portion may remain on the plate glass G without coming into contact with the end face ES. In order to prevent such a situation, it is desirable that the correction factor CF of the processing tool 2 related to the separation direction CDb is set smaller than the correction factor CF of the processing tool 2 related to the approaching direction CDa.

When correcting the reference position RP on the approach direction CDa side, it is desirable to set the correction factor CF to, for example, 50 to 100%. The correction factor CF when correcting the reference position RP on the CDb side in the separation direction is preferably set to, for example, 10 to 50%.

Hereinafter, the determination step S3 and the correction step S4 by the control device 5 will be described in detail with reference to FIG. FIG. 8 exemplifies a part of the processing history data created by the arithmetic processing unit 9 when processing a plurality of flat glass G included in one lot.

This history data shows a case where the processing of ten flat glass plates G1 to G10 is completed and the next flat glass plate G11 is processed. The history data includes the value of the movement amount D of the processing tool 2 corresponding to each of the flat glass G1 to G10. Hereinafter, the determination step S3 and the correction step S4 when the correction factor CF is set to 80% and the threshold value TH1 is set to +0.040 mm will be described.

Since the arithmetic processing unit 9 of the control device 5 updates the reference position RP based on the movement amount D of the processing tool 2 corresponding to the one sheet glass G measured most recently, the processing of one sheet glass G is completed. The determination step S3 is executed every time.

The determination unit 12 of the arithmetic processing unit 9 compares the data of the movement amount D of the processing tool 2 corresponding to the plate glass G10 processed prior to the plate glass G11 with the threshold value TH1. In this example, since the movement amount D (+0.060 mm) corresponding to the flat glass G10 exceeds the threshold value TH1 (+0.040 mm), the correction step S4 is executed. In the correction step S4, the arithmetic processing unit 9 multiplies the data of the movement amount D corresponding to the flat glass G10 by the correction factor CF (80%) based on the above equation (1), and sets the correction value CV to 0. Obtain 048 mm. Unlike this example, when the movement amount D corresponding to the flat glass G10 does not exceed the threshold value TH1, the correction step S4 is not executed, and the reference position RP related to the next processing of the flat glass G11 is the previous flat glass. It becomes the same as the reference position RP related to the processing of G10.

The control device 5 adds the above correction value CV to the value of the reference position RP set at the time of the most recent machining of the flat glass G10, and sets a new reference position RP for the next machining of the flat glass G11. do. The control device 5 transmits the control data related to the updated reference position RP to the arm position control unit 8. In the preparation step S1 of the flat glass G11, the arm position control unit 8 installs the grindstone 6 at the new reference position RP. As a result, the reference position RP in the preparation step S1 of the plate glass G11 moves by the correction value CV from the reference position RP in the preparation step S1 of the previous plate glass G10.

When processing a plurality of plate glasses G in order, it is desirable to use the average value of the movement amount D of the processing tools 2 related to the plurality of plate glasses as the movement amount D in the correction step S4. The determination step S3 and the correction step S4 when the average value is used in this way will be described. The values of the threshold value TH1 and the correction factor CF are the same as those in the above example. In this example, the average value of the movement amount D of the processing tool 2 related to the last three times of processing with respect to the next processing of the plate glass G11, that is, the average value of the movement amount D of the processing tool 2 related to the plate glasses G8 to G10. Is used to calculate the correction value CV.

In the determination step S3, the determination unit 12 of the arithmetic processing unit 9 compares the data of the movement amount D of the processing tool 2 corresponding to the plate glass G10 processed prior to the plate glass G11 with the threshold value TH1. In this example, since the movement amount D (+0.060 mm) of the processing tool 2 corresponding to the flat glass G10 exceeds the threshold value TH1 (+0.040 mm), the correction step S4 is executed. In the correction step S4, the arithmetic processing unit 9 of the control device 5 refers to the history data and sets the reference position RP of the processing tool 2 related to the next plate glass G11, so that the processing tool 2 related to the plate glass G8 to G10 is set. The average value (0.040 + 0.050 + 0.060) / 3 of the movement amount D of is calculated.

The arithmetic processing unit 9 multiplies the calculated average value (+0.050 mm) by the correction factor CF (80%) to obtain +0.040 mm as the correction value CV. In the same manner as described above, the arithmetic processing unit 9 adds the above correction value CV to the value of the reference position RP set at the time of the most recent machining of the flat glass G10, and newly performs the next machining of the flat glass G11. Set the reference position RP. Then, the control device 5 transmits a control signal related to the new reference position RP to the arm position control unit 8.

9 to 11 show a control mode when the processing tool 2 installed at the reference position RP moves in the separation direction CDb.

As shown in FIG. 9, in the preparation step S1, while the machining tool 2 moves along the moving direction F, the arm position control unit 8 uses the grindstone 6 at the standby position SP (position indicated by the alternate long and short dash line) as a reference position. Move to RP (position shown by solid line in FIGS. 9 and 10).

When the grindstone 6 is installed at the reference position RP, the pressing force generating element 3 starts the constant pressure control of the grindstone 6. In this example, the grindstone 6 comes into contact with the processing start portion C1 of the plate glass G immediately after being installed at the reference position RP. At this time, the pressing force generating element 3 detects an excessive pressing force acting on the grindstone 6. Since the grindstone 6 is urged by the pressing force generating element 3 with a constant pressing force, the grindstone 6 moves from the reference position RP to the separation direction CDb.

In the measurement step S2, the control device 5 has a negative (-) movement amount D (-) related to the separation direction CDb of the grindstone 6 based on the position information of the processing tool 2 (grindstone 6) received from the measuring unit 4 (FIG. 10). And FIG. 11).

In the determination step S3, the control device 5 compares the movement amount D of the grindstone 6 calculated by the determination unit 12 of the arithmetic processing unit 9 with the negative (−) threshold value TH2. When the movement amount D exceeds the threshold value TH2, the arithmetic processing unit 9 updates the reference position RP of the processing tool 2 (grinding stone 6) related to the next processing based on the above equation (1). The control device 5 transmits a control signal related to the updated new reference position RP to the arm position control unit 8.

When the grindstone 6 has a plurality of groove portions 6a, for example, the plurality of groove portions 6a are sequentially used for end face processing. More specifically, after the end face processing is performed using the groove portion 6a located at the uppermost stage, the end face processing is performed using the groove portion 6a located at the second stage from the top, and then the position is performed at the third stage from the top. End face processing is performed using the groove portion 6a to be formed. After using all the groove portions 6a in this way, dressing is applied to all the groove portions 6a as needed, and the plurality of groove portions 6a are used again in order for end face processing. In such a usage pattern, each groove portion 6a of the grindstone 6 is gradually worn while the end face processing is repeated, and the degree of wear is different for each groove portion 6a. Therefore, as shown in FIG. 12, the depth of each groove portion 6a varies depending on the progress of processing. Therefore, if the plate glass processing apparatus 1 sets the reference position RP for each of the groove portions 6a having different depths, the processing tool 2 can be installed in the reference position RP corresponding to each groove portion 6a at the start of processing.

According to the method for manufacturing the plate glass G according to the present embodiment described above, the movement amount D of the processing tool 2 when the processing tool 2 comes into contact with the end face of the plate glass G is measured in the measuring step S2, and in the correction step S4, the moving amount D is measured. Based on this movement amount D, the reference position RP of the processing tool 2 related to the next processing is set. As a result, the reference position RP of the processing tool 2 related to the next processing can be optimized according to the change in the positional relationship between the processing tool 2 and the flat glass G due to the influence of the wear of the processing tool 2. Therefore, it is possible to prevent the occurrence of processing defects on the end face ES of the flat glass G and to extend the life of the processing tool 2.

The present invention is not limited to the configuration of the above embodiment, and is not limited to the above-mentioned action and effect. The present invention can be modified in various ways without departing from the gist of the present invention.

In the above embodiment, an example in which the pressing force generating element 3 is configured by an air cylinder is shown, but the present invention is not limited to this configuration. For example, a link mechanism and a servomotor are connected to the arm member 7, the rotational force of the drive shaft of the servomotor is converted into a couple of the arm member 7 via the link mechanism, and this force is converted into the pressing force of the processing tool 2. May be. In this case, the position information of the processing tool 2 may be detected based on the rotation angle of the servomotor.

In the above embodiment, the correction step S4 is executed when the movement amount D of the processing tool 2 exceeds the threshold values TH1 and TH2 in the determination step S3, but the present invention is not limited to this, and the threshold value is set. Instead, the correction step S4 may be executed every time.

In the above embodiment, an example of determining using the movement amount D in the determination step S3 when processing a plurality of flat glass G in order is shown, but the present invention is not limited to this, and a plurality of movement amounts D in the determination step S3 are shown. The average value of the movement amount of the processing tool 2 related to the plate glass G may be used.

2 Processing tool 5 Control device 6a Groove CDa Approach direction CDb Separation direction D Movement amount ES Plate glass end face G Plate glass RP reference position S1 Preparation process S2 Measurement process S3 Judgment process S4 Correction process

Claims (5)

In a method for manufacturing a flat glass, which comprises an end face processing step of processing the end face of the flat glass with a processing tool.
The machining tool is a constant pressure type machining tool that is configured to be movable in the approaching direction or the separating direction with respect to the end face and is in contact with the end face at a constant pressure.
The end face machining step includes a position control step of controlling the position of the machining tool by a control device.
The position control step is
A preparatory step for arranging the processing tool in a reference position before the start of processing and before the processing tool comes into contact with the end face.
A measuring step of measuring the amount of movement of the processing tool in the approaching direction or the separation direction when the processing tool comes into contact with the end face at the start of processing, and a measurement step.
A determination step for determining whether or not the movement amount exceeds the threshold value, and
A correction step of setting the reference position of the processing tool related to the next processing based on the movement amount is provided .
Wherein the correction step, the manufacturing method of sheet glass the amount of movement in the determining step is characterized Rukoto is executed if it is determined to exceed the threshold. In the correction step, a correction value for setting the reference position of the processing tool in the next machining is calculated based on the movement amount.
The correction value is, the production method of the glass sheet according to claim 1 which is calculated by the following equation (1).
CV = CF × X ・ ・ ・ (1)
(However, CV is the correction value, CF is the correction factor, and X is the movement amount.) In the correction step, the correction factor when the movement amount indicates the movement of the processing tool in the separation direction is smaller than the correction factor when the movement amount indicates the movement of the processing tool in the approaching direction. The method for manufacturing a flat glass according to claim 2. In the measurement step, when a plurality of the plate glasses are processed, the movement amount is measured for each of the plate glasses.
The method for manufacturing a flat glass according to any one of claims 1 to 3 , wherein in the correction step, an average value of the moving amounts of a plurality of the flat glass is used as the moving amount. The processing tool is a grindstone having a plurality of grooves for processing the end face.
The method for manufacturing a flat glass according to any one of claims 1 to 4 , wherein the control device sets the reference position for each groove.

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