WO2013105341A1

WO2013105341A1 - Dressing method for glass substrate edge-grinding grindstone and glass substrate manufacturing method using said dressing method

Info

Publication number: WO2013105341A1
Application number: PCT/JP2012/079994
Authority: WO
Inventors: 潤大川; 勝俊福間; 秀之遠藤; 宮本　幹大
Original assignee: 旭硝子株式会社
Priority date: 2012-01-13
Filing date: 2012-11-19
Publication date: 2013-07-18
Also published as: JPWO2013105341A1; TW201330981A; CN103945985A; KR20140123038A; JP5500313B2

Abstract

A dressing method for a glass substrate edge-grinding grindstone and a glass substrate manufacturing method using said dressing method. The glass substrate edge-grinding grindstone dressing method is characterized in that: a glass substrate is used as the dressing material; and the glass substrate being used as the dressing material is supplied to the edge-grinding grindstone so that the feed rate for the glass substrate being used as the dressing material is slower than the feed rate for glass substrates when the edges thereof are ground during product manufacture, and the grinding allowance for the glass substrate being used as the dressing material is greater than the grinding allowance for glass substrates when the edges thereof are ground during product manufacture.

Description

Method for dressing a grinding wheel for end grinding of a glass substrate and method for producing a glass substrate using the dressing method

The present invention relates to a dressing method for a grindstone for grinding an end face of a glass substrate and a method for producing a glass substrate using the dressing method.

A glass substrate such as a plate glass or a liquid crystal panel is cut into a predetermined size and then processed into a glass substrate having a product outer diameter by grinding and chamfering the end faces of the four sides.

Grinding processing for performing such grinding and chamfering is performed by rotating a cylindrical grindstone having a groove formed on its side surface along the circumferential direction, and the groove portion (groove surface) of the glass substrate to be ground. This is performed by moving the glass substrate or the grindstone while applying the end face (for example, Patent Document 1).

Grinding processing of the glass substrate end face can be carried out continuously for a plurality of glass substrates, but as the amount of grinding increases, the clogging of the surface of the grindstone groove (loading), or the abrasive grains falling Spilling or the like occurs and the processing ability of the grindstone decreases. For this reason, dressing is performed in which the end surface grinding apparatus for the glass substrate is periodically stopped to sharpen the grindstone and restore its ability.

Japanese Patent Application 2010-268055

However, according to the conventional dressing method, it is necessary to stop the end surface grinding device during dressing and to apply the dressing material to the end surface grinding wheel.

For this reason, there was a problem that the operating rate of the end face grinding device was lowered and the productivity was lowered.

Furthermore, since the operator performs dressing manually, the surface condition of the grindstone groove after dressing varies by the operator, and even if dressing is performed, the grindstone processing capacity does not recover, or the grindstone groove There was also a problem that the shape of the case may be deformed.

In view of the problems of the prior art described above, the present invention can perform dressing without stopping the end surface grinding apparatus for the glass substrate, and can stably recover the processing ability of the grindstone regardless of the operator. It aims at providing the dressing method of the grindstone for the end surface grinding of a glass substrate.

According to one embodiment, there is provided a dressing method for a grindstone for grinding an end surface of a glass substrate, wherein the glass substrate is used as a dressing material, and the feed rate of the glass substrate used as a dressing material is ground at the time of product manufacture. The end surface grinding is performed so that the amount of grinding of the glass substrate used as a dressing material is slower than the feeding rate of the glass substrate at the time of manufacture, and is larger than the amount of grinding of the glass substrate when the end surface is ground during product manufacture. A glass dressing method for grinding an end surface of a glass substrate is provided, wherein the glass substrate used as a dressing material is supplied to a grinding wheel for use.

According to another aspect, at the time of product manufacture, a normal process of grinding the end face of the glass substrate with a first grinding amount while feeding the glass substrate to the grindstone for end face grinding at a first feed rate; A step of determining whether or not dressing of the end surface grinding wheel is necessary at a predetermined timing; and when the dressing is determined to be necessary, the first feeding of the glass substrate to the end surface grinding wheel A dressing step of grinding the end face of the glass substrate with a second grinding amount larger than the first grinding amount while feeding at a second feeding speed slower than the speed;
The manufacturing method of the glass substrate containing this is provided.

Side view of an end surface grinding apparatus for a glass substrate according to an embodiment The top view of the end surface grinding device of the glass substrate concerning an embodiment Explanatory drawing of the grindstone for end surface grinding used with the end surface grinding apparatus of the glass substrate which concerns on embodiment Control flow of dressing according to the embodiment Observation view of groove surface of grindstone after dressing of Example 3-1 in Example 3 Observation view of groove surface of grindstone before start of use of Example 3-1 in Example 3 Observation view of groove surface of grindstone after dressing in Example 3-2 in Example 3 Observation view of groove surface of grindstone before use of Example 3-2 in Example 3 Diagram showing an example of controller configuration

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. However, the present invention is not limited to the following embodiments, and the following embodiments are not departed from the scope of the present invention. Various modifications and substitutions can be made.

In the present embodiment, a method for dressing a grindstone for grinding an end face of a glass substrate will be described.

First, a configuration example of a glass substrate end surface grinding apparatus provided with an end surface grinding wheel will be described with reference to FIGS. 1A, 1B, and 2. FIG.

1A and 1B are schematic views of the glass substrate end surface grinding apparatus 10, FIG. 1A is a side view, and FIG. 1B is a top view. In addition, the dressing method of this Embodiment is not limited to the end surface grinding apparatus which concerns.

The rectangular workpiece W (glass substrate) to be ground is detachably held on the holding means 11 with the end face exposed from the holding means 11. The holding means 11 is disposed on a traveling body S that can move in the left-right direction in FIG. 1 (the arrow direction in FIG. 1A and FIG. 1B). It is configured to be transportable. Moreover, the conveyance mechanism 12 can be comprised so that the conveyance speed (feeding speed) of the workpiece | work W can be controlled by the controller 100 (control part) mentioned later.

The workpiece W held on the holding means 11 is transferred by the transfer mechanism 12 to the position where the grinding mechanism 13 is installed, and grinding and chamfering processing (hereinafter simply referred to as grinding processing) is performed on both end portions thereof. Is done. FIG. 1B shows an example in which one grinding mechanism 13 is arranged on each of the left and right sides of the conveyance mechanism 12 (in the direction orthogonal to the conveyance direction of the workpiece W) (in FIG. 1A, only one grinding mechanism 13 is shown for easy understanding of the structure). For example, a plurality of grinding mechanisms can be arranged in the conveying direction by changing the type and roughness of the grindstone as in rough grinding and finishing.

The grinding mechanism 13 is preferably configured so that the distance from the workpiece W can be changed manually or automatically in order to adjust the grinding amount (grinding width). Specifically, for example, the grinding mechanism 13 is preferably provided with a servo mechanism or the like. In the present embodiment, the position of the grinding mechanism 13 (distance from the workpiece W) can also be configured to be controlled by the controller 100 (control unit) described later.

As shown in FIG. 1B, the grinding mechanism 13 has a cylindrical end grinding wheel (hereinafter, also simply referred to as “grinding stone”) 132 inside the grinding mechanism 13, and the grinding stone 132 at the center axis of the grinding stone 132 during grinding processing. A motor 131 is provided for rotationally driving the motor as a rotation axis. Further, a grinding mechanism 13 includes a coolant supply mechanism 14 for supplying coolant (coolant) to the periphery of a portion where the grindstone 132 and the workpiece W are in contact with each other, and a suction mechanism 15 for drawing the used coolant through the duct L. Can be connected to.

Normally, the coolant supplied to the periphery of the portion where the grindstone and the workpiece W come into contact with each other during grinding by the coolant supply mechanism 14 is collected by the suction mechanism 15 and then circulated and used by removing foreign substances with a filter or the like. For this reason, when a dressing material made of a material different from the workpiece W (glass substrate) of the object to be ground is used as in the conventional dressing method, the dressing material is mixed into the coolant and cannot be removed by a filter during the grinding process. There was a problem that the workpiece W was scratched by the foreign matter. However, according to the dressing method of the present embodiment, since a glass substrate is used as a dressing material, foreign substances (those different from an object to be ground) are not mixed into the coolant even after performing dressing. The problem can be solved.

The type of the grindstone 132 is not particularly limited, and for example, a diamond grindstone can be used. Further, as can be seen from the lateral side view of the grindstone shown in FIG. 2, a groove 132 (a) is formed on the side surface (circumferential surface) of the grindstone 132, and the end surface of the workpiece W is applied to the groove. By conveying the workpiece W, the grinding process of the end surface of the workpiece W is performed. At this time, the end face of the workpiece W is chamfered according to the surface shape of the groove. FIG. 2 shows an example in which one groove 132 (a) is provided. For example, a plurality of grooves are provided at predetermined intervals in the axial direction, and each groove is ground when continuously operating the end face grinding apparatus. Depending on the amount or the like, the groove to be used can be switched.

In addition, although the end surface grinding apparatus which conveys the workpiece | work W and grinds the end surface was demonstrated here, you may comprise so that the workpiece | work W may be fixed and the grinding mechanism 13 may move, You may comprise so that both of the grinding mechanisms 13 may be conveyed and moved.

The present embodiment relates to a dressing method for an end surface grinding wheel arranged in a grinding mechanism in the above-described glass substrate end surface grinding apparatus, and the dressing method of the present embodiment will be described below.

If grinding is performed under normal grinding conditions (product manufacturing conditions), clogging of the surface of the grindstone grooves due to chips (grinding debris) or spilling of abrasive grains may occur. Waking up, the processing capacity of the grindstone will decline.

In the dressing method of the present embodiment, a glass substrate is used as a dressing material, and the feed rate of the glass substrate is made slower than the conditions for grinding the end face during normal product manufacturing, and the amount of grinding of the glass substrate is increased. Thus, a glass substrate is supplied to the grindstone for end face grinding (end face grinding apparatus) to recover the processing ability of the grindstone.

This is to remove the chips (grinding debris) adhering to the surface of the grindstone groove by slowing the feed rate and increasing the amount of grinding than the conditions for normal product processing of the glass substrate, This is probably because part of the abrasive bond material that is easily cut out of the grindstone is removed, and the effect of putting the abrasive grains on the surface of the grindstone groove is obtained.

Here, the feeding speed of the glass substrate is a relative speed between the glass substrate and the grinding mechanism section. For example, as shown in FIGS. 1A and 1B, the grinding mechanism 13 is fixed, and the end surface grinding is performed to convey the glass substrate. In an apparatus, it means the conveyance speed of a glass substrate (workpiece). Further, when the glass substrate is fixed and the grinding mechanism 13 is moved, it means the moving speed of the grinding mechanism 13, and when both the glass substrate and the grinding mechanism 13 are transported and moved, the relative speed between the two is determined. Means.

Further, the grinding amount (processing amount) means the size (width) of the grinding allowance when the glass substrate end face is ground.

The conditions of grinding processing during normal product manufacturing are defined by the characteristics of the edge grinding machine, the shape of the glass substrate, the surface roughness required for the glass substrate product, the type of grindstone (for example, surface roughness and type), etc. Is done. For this reason, the conditions for the grinding processing of the glass substrate end face during normal product production are not limited. For example, the feed rate of the glass substrate is 6000 to 24000 mm / min, and the grinding amount is 80 to 240 μm. It is preferable to carry out under conditions.

And the dressing method of this embodiment is a glass substrate that is a dressing material for the grindstone for end face grinding so that it is slower than the feed rate of the glass substrate for the grinding process at the time of product manufacture and the grinding amount is increased. Any other method may be used, and other conditions are not limited.

The feeding speed of the glass substrate used as the dressing material can be set to 1/6 or more of the feeding speed of the glass substrate when the end surface is ground during the production of the product. By reducing the glass substrate feed rate used as the dressing material to 1/6 or more of the glass substrate feed rate at the time of product manufacture, the reduction in the operating rate of the glass substrate end face grinding device is suppressed, and the productivity is improved. Can be maintained. Moreover, the feed rate of the glass substrate used as a dressing material can be set to 1/3 or less of the feed rate of the glass substrate when the end surface is ground during product production. A sufficient dressing effect can be obtained by setting the feeding speed of the glass substrate used as the dressing material to 1/3 or less of the feeding speed of the glass substrate at the time of manufacturing the product.

The amount of grinding of the glass substrate used as the dressing material can be 1.1 times or more of the amount of grinding of the glass substrate when the end surface is ground during product production. A sufficient dressing effect can be obtained by making the grinding amount of the glass substrate used as the dressing material 1.1 times or more of the grinding amount of the glass substrate at the time of manufacturing the product. Moreover, the grinding amount of the glass substrate used as a dressing material can be 3.5 times or less of the grinding amount of the glass substrate when the end surface is ground during the production of the product. By setting the grinding amount of the glass substrate used as the dressing material to 3.5 times or less of the grinding amount of the glass substrate at the time of product manufacture, it is possible to prevent the glass substrate from being broken during the grinding process.

The glass substrate used as the dressing material is not particularly limited, and various glass substrates can be used. For example, a glass substrate can be prepared exclusively for dressing and used for dressing. Moreover, the glass substrate used at the time of normal product manufacture can also be used.

When a dedicated glass substrate is prepared for dressing, the size is not particularly limited as long as a sufficient amount of grinding can be ensured. However, it is preferable that the size is the same as that of a glass substrate of a normal product so that the configuration and arrangement of the end face grinding apparatus need not be changed. In particular, it is preferable to use a glass substrate having the same thickness as the glass substrate of the product so as to correspond to the surface shape of the groove of the grindstone. Although the material is not particularly limited, it is preferable to use a glass substrate made of the same material as the glass substrate for products.

Moreover, the glass substrate used as the dressing material can be used either a glass substrate that has been subjected to end face grinding processing or a glass substrate that has not been subjected to grinding processing.

As shown in Examples 1 and 2 to be described later, the glass substrate used as the dressing material is sufficient without changing the surface shape of the groove of the grindstone regardless of the presence or absence of the grinding process (chamfering process) of the end face part. This is because the effect of dressing can be obtained.

In particular, when a glass substrate that has not been subjected to grinding processing of the end face portion in advance is used, the step of processing the glass substrate in advance can be omitted, so that the working efficiency can be increased, which is preferable from the viewpoint of cost.

In this case, for example, dressing can be performed without changing the glass substrate only by changing the operating conditions of the end grinding device for glass substrate that has been operating normally (slowing the feed rate and increasing the grinding amount). It can be performed. Furthermore, after the dressing is completed, the glass substrate end face can be ground by returning to normal operating conditions. For this reason, since the fall of the operation rate of the end surface grinding apparatus of a glass substrate can also be suppressed especially, it is preferable.

Further, it is preferable to use (can be used) a glass substrate used as a dressing material. For example, when a glass substrate used at the time of product manufacture is used as a dressing material, it can be used as a product as long as the amount of grinding increased during dressing is within the tolerance range of the product. In this case, it is not necessary to discard or rework the glass substrate used for dressing, which is preferable from the viewpoint of reducing the cost and environmental burden.

When performing dressing, it is not necessary to perform with only one glass substrate. For example, if the effect of dressing is not enough with only one glass substrate, or if the grinding amount cannot be secured sufficiently due to the processing accuracy (tolerance) required for the product, two or more It is also possible to perform dressing using a glass substrate.

The timing for performing the dressing method of the present embodiment is not particularly limited, and can be arbitrarily set. For example, it is possible to perform dressing periodically based on the accumulated grinding amount of the grinding wheel for end face grinding (groove of the grindstone), or to inspect the ground product and perform it at an arbitrary timing based on the inspection result.

Fig. 3 shows an example of a specific dressing control flow. In this method, dressing is performed at an arbitrary timing based on the accumulated grinding amount of the grindstone for end face grinding.

First, a grindstone for end face grinding is set in the end face grinding apparatus 10 for the end face of the glass substrate, and operation is started under the conditions at the time of product manufacture. Here, the grinding wheel cumulative grinding amount (A) for counting the cumulative grinding amount (processing amount) of the end face grinding wheel is reset to 0 (step S10). Further, the dressing interval grindstone integrated grinding amount (B), which is the cumulative grinding amount (processing amount) since the last dressing, is reset to 0 (step S12).

Thereafter, an end surface grinding process of the glass substrate is performed (step S14). This step is a step of grinding the end face of the glass substrate during product manufacture. The glass substrate is fed to the end surface grinding wheel at a first feed rate, and the end surface of the glass substrate is ground with a first grinding amount. Accordingly, the value of the grinding wheel cumulative grinding amount (A) and the dressing interval grinding wheel cumulative grinding amount (B) are counted up according to the grinding amount (step S16).

In the course of grinding the glass substrate end face, the following determination is made at a predetermined timing (for example, every time one glass substrate end face grinding process is performed).

First, it is determined whether the grinding wheel cumulative grinding amount (A) has reached the set value (A1) (step S18). Here, the set value (A1) defines the accumulated grinding amount of the end surface grinding wheel from when the end surface grinding wheel is installed in the end surface grinding device to when it needs to be replaced. It is defined in advance based on the grindstone for end face grinding, the type of glass substrate to be ground, and the like. That is, since the set value (A1) is defined as a limit value that can be used for the grindstone for end face grinding, it is necessary to replace the grindstone for end face grinding when it is determined that the set value (A1) has been reached. For this reason, when it is determined that the set value (A1) has been reached (Yes in step S18), the operation is stopped (step S34), and the end grinding wheel is replaced. If it is determined that the set value (A1) has not been reached (No in step S18), the process proceeds to the next determination.

Next, as a result of inspecting the end face of the manufactured glass substrate, it is determined whether or not an arbitrary glass dressing start button that is arbitrarily pressed when it is determined that sufficient grinding is not performed. (Step S20).

When the arbitrary glass dressing start button is pressed (Yes in step S20), a dressing process (step S24) described later is performed. If it is determined that the button has not been pressed (No in step S20), the process proceeds to the next determination.

Then, it is determined whether the dressing interval grinding wheel cumulative grinding amount (B) has reached the set value (B1) (step S22). Here, the set value (B1) defines the cumulative grinding amount of the grindstone for end face grinding after dressing until the next dressing. Similarly to the case of the set value (A1), the set value (B1) is defined in advance based on, for example, the configuration of the end face grinding apparatus, the grindstone for end face grinding, the type of the glass substrate to be ground, and the like. .

If it is determined that the set value (B1) has not been reached (No in step S22), the grinding process of the glass substrate end face is repeated.

If it is determined that the set value (B1) has been reached (Yes in step S22), the set value (B1) as described above is accumulated from the last dressing to the next. Since the amount of grinding is determined, dressing is automatically executed (step S24).

For dressing, the glass substrate feed speed (grinding wheel processing speed) is changed to the dressing feed speed as described above, and the position of the grinding mechanism is changed so that the grinding amount becomes a condition for dressing (step). S26). Thereafter, dressing is performed using the glass substrate as a dressing material (step S28). This step is a step of dressing the grindstone for end face grinding using the end face of the glass substrate as a dressing material for the grindstone for end face grinding. Here, the glass substrate is fed to the edge grinding wheel at a second feed rate that is slower than the first feed rate. Further, the end surface of the glass substrate is ground with a second grinding amount larger than the first grinding amount. Specifically, the grinding mechanism 13 is controlled to reduce the distance between the grindstone for end face grinding and the end face of the glass substrate used as the dressing material.

After performing the process of dressing the grinding wheel for end face for a predetermined time, the feed speed and the grinding amount are returned to the normal operating conditions, that is, the original setting values (conditions for manufacturing the product) during the grinding process (steps S30 and S32). ). Then, the dressing interval grindstone integrated grinding amount (B) is reset to 0 (step S12), and the grinding processing of the glass substrate end face is performed again.

By repeatedly grinding the glass substrate end face according to the above flowchart, the glass substrate end face can be ground while performing dressing at a predetermined timing without stopping the end face grinding device for the glass substrate end face. .

Further, the determinations in steps S14 to S22 can be made every time processing is performed on a predetermined number (one or more) of glass substrates.

Next, the configuration of the controller 100 will be described. FIG. 5 is a block diagram functionally showing the configuration of the controller 100. The controller 100 includes a control unit 102 and a setting condition storage unit 104.

The setting condition storage unit 104 includes the setting value (A1), the setting value (B1), the glass substrate feed speed and the grinding amount (position of the grinding mechanism 13) under normal operating conditions (product manufacturing), and the glass dressing time. Preset conditions such as the glass substrate feed speed and grinding amount (position of the grinding mechanism 13), the predetermined timing for determining in steps S18 to S22 in FIG. 3, the predetermined execution time for performing glass dressing, and the like are stored. . A plurality of these conditions can be set according to the type of glass substrate and the required product characteristics.

In addition, as described with reference to FIG. 1B, for example, when a plurality of grinding mechanisms 13 are arranged in the transport direction by changing the type and roughness of the grindstone for rough grinding and finishing, each grinding mechanism 13 You can set conditions. The setting condition storage unit 104 stores these conditions.

Further, the predetermined execution time for performing the glass dressing can be set, for example, according to the feed rate and the grinding amount of the glass substrate during the glass dressing. For example, as described above, when the grinding amount at the time of dressing is the same as that at the time of normal operation, the predetermined execution time for performing the glass dressing can be set to be long. In addition, the distance for performing glass dressing and the number of glass substrates for performing glass dressing can be set instead of the predetermined execution time for performing glass dressing.

The control unit 102 refers to the conditions set in the setting condition storage unit 104 and controls each procedure in the flowchart shown in FIG. Further, the control unit 102 controls the transport mechanism 12 and the grinding mechanism 13 based on the conditions set in the setting condition storage unit 104 so that the normal operation conditions and the glass dressing are performed.

In addition, when the arbitrary glass dressing start button described above is pressed, for example, the setting of a flag indicating that is turned on, and the control unit 102 refers to the flag and performs the determination in step S20 of FIG. Can do.

For example, the controller 100 can be configured by a computer having a central processing unit (CPU) that performs various controls, an input / output device, a storage device, and the like, and a configuration in which an execution program that causes the computer to execute each function described above is installed. can do.

When the dressing method of the edge grinding wheel of the glass substrate described so far is used in the glass substrate manufacturing process, that is, when the glass substrate manufacturing method using the dressing method is used, the glass substrate manufacturing apparatus is stopped. It becomes possible to perform dressing of a grindstone without this. For this reason, productivity is improved as compared with the prior art, and it is not necessary for the operator to manually perform dressing, and dressing can be easily performed.

And, the surface condition of the groove of the grindstone after dressing by the operator does not occur as in the conventional case, the processing ability of the grindstone can be stably recovered, and the surface shape of the groove formed on the grindstone is deformed. Can also prevent. For this reason, it becomes possible to manufacture more stable quality glass substrates continuously.

Specific examples will be described below, but the present invention is not limited to these examples.
[Example 1]
In the present example, in the glass substrate end surface grinding apparatus having the same configuration as that shown in FIGS. 1A and 1B, dressing was performed on an end surface grinding grindstone that had undergone a grinding process on the glass substrate end surface to reduce the processing ability. As the grindstone for end face grinding, a cylindrical one having a diameter of 150φ was used, and a diamond grindstone in which eight grooves having the same shape were formed on the side surface was used. As shown in Table 1, the eight grooves formed on the side surface of the grindstone for end face grinding are in the same state with a cumulative processing (grinding) distance of about 1500 m, and each groove was dressed and evaluated. Eight grooves correspond to Examples 1-1 to 1-8 in Table 1.

Dressing is performed using the same material and the same size glass substrate (non-alkali glass, manufactured by Asahi Glass Co., Ltd., product name: AN100) as that used during normal product manufacturing, one for each groove. It was. Specifically, a glass substrate having a size of 1850 mm in width, 1500 mm in length, and 0.7 mm in thickness and not subjected to end face grinding in advance was used in this example.

Usually, when grinding a glass substrate end surface for a product, in the glass substrate end surface grinding apparatus under the conditions of a feed rate of 6000 mm / min and a grinding amount of 150 μm, Table 1-1 shows Examples 1-1 to As shown in Example 1-8, dressing was performed by changing the feed rate and grinding amount for each groove.

Evaluation was made by observing and comparing the groove surface of the grindstone with a microscope (trade name: VHX-100F, manufactured by Keyence Corporation) before and after dressing. The results are shown in Table 1.

In Table 1, circles were given for those where the effect of dressing was seen, and double circles were given for those that had recovered to the state of the groove surface of the grindstone before the start of use (similar to that at the time of shipment).

According to this, it was confirmed that the effect of dressing can be obtained by slowing the glass substrate feed rate and increasing the grinding amount for any sample (groove). In particular, Example 1-4 in which the feed rate is 1000 mm / min and the grinding amount is 500 μm and Example 1-8 in which the feed rate is 2000 mm / min and the grinding amount is 400 μm are recovered to the same level as before the use of the grindstone. It was confirmed that

In any case, no significant change was observed in the surface shape of the groove formed on the side surface of the grindstone before and after dressing, and it was confirmed that dressing was performed appropriately.

[Example 2]
In this example, the feed rate and the grinding amount were changed for each groove in the same manner as in Example 1 except that a glass substrate that had been subjected to end face grinding processing in advance was used as the glass substrate used for dressing. The experiment was conducted.

The glass substrate that has been subjected to the end surface grinding processing in advance here is a glass substrate that has been subjected to grinding processing once for the end surface of the glass substrate using the same glass substrate end surface grinding device under the conditions for normal products. It means that there is.

Also in this example, as the grinding wheel for end face grinding, a 150φ cylindrical one was used as in Example 1, and a diamond grinding stone having eight grooves of the same shape formed on its side surface was used. As shown in Table 2, the eight grooves formed on the side surface of the grindstone for end face grinding were in the same state with a cumulative processing (grinding) distance of about 1500 m, and each groove was dressed and evaluated. Eight grooves correspond to Examples 2-1 to 2-8 in Table 2.

Regarding the evaluation, the surface of the grindstone groove surface was observed and compared with a microscope (trade name: VHX-100F, manufactured by Keyence Corporation) before and after dressing in the same manner as in Example 1. The results are shown in Table 2.

Also in Table 2, circles are marked for dressing effects, and double circles are marked for those in which the condition of the groove surface of the grinding stone has recovered before the start of use (similar to when the grinding wheel is shipped). did.

According to this, it was confirmed that the effect of dressing can be obtained by slowing the glass substrate feed rate and increasing the grinding amount for any sample (groove). In particular, Example 2-4 in which the feed rate is 1000 mm / min and the grinding amount is 500 μm and Example 2-8 in which the feed rate is 2000 mm / min and the grinding amount is 400 μm are recovered to the same level as before the start of use of the grindstone. It was confirmed that

In any case, no significant change was observed in the surface shape of the groove before and after dressing, and it was confirmed that dressing was performed appropriately.

When the results of Examples 1 and 2 are compared, the effect of dressing is obtained regardless of whether the grinding process of the glass substrate end surface is performed in advance, and the dressing is performed regardless of the presence or absence of the grinding process on the glass substrate end surface. It was confirmed that the effect was obtained.

[Example 3]
In the present Example, in the end surface grinding apparatus of the glass substrate which has the same structure as FIG. 1A and FIG. 1B, dressing was performed by changing the kind of glass substrate with Example 1,2.

Dressing was performed using a glass substrate (soda lime glass, manufactured by Asahi Glass Co., Ltd., product name: PD200) having the same material and size as those used during normal product manufacture as a dressing material. The size of the glass substrate was 2250 mm wide × 1900 mm long × 1.8 mm thick, and a glass substrate not subjected to end face grinding was used.

As shown in Table 3 in Example 3 and Example 3-2, dressing was performed with two types of diamond grinding stones having different surface roughness. The grindstone for end face grinding was a cylindrical shape of 204φ, and one having grooves formed on the side surface of the grindstone was used. In Example 3-1, dressing was performed for an accumulated machining distance of 16000 m, and in Example 3-2, dressing was performed for an accumulated machining distance of 6000 m. In addition, in Example 3-1 and Example 3-2, the cumulative machining distance after the last dressing is 1000 m.

In both cases of Example 3-1 and Example 3-2, during normal product manufacturing, the glass substrate end face is ground under the conditions of a glass substrate feed rate of 20000 mm / min and a grinding amount of 160 μm. The conditions were such that the glass substrate feed rate was 4000 mm / min and the grinding amount was 500 μm.

For evaluation, the surface roughness, protrusion amount, and wear amount were measured before the start of use (the state at the time of grinding wheel shipment) and the groove portion of the grinding wheel for end face grinding after dressing. The surface roughness was measured using a surface roughness meter (product name: Surfcom 1400A-12, manufactured by Tokyo Seimitsu Co., Ltd.). Further, the groove portion was magnified 100 times using a microscope (trade name: VHX-100F, manufactured by Keyence Corporation), and the surface was observed.

Table 3 shows the measurement results of the surface roughness, protrusion amount, and wear amount.

4A to 4D show surface images of the groove portion of the grinding wheel for end face grinding before use and after dressing.

4A and 4B are surface images of the groove portion of the grinding wheel for end face grinding in Example 3-1, FIG. 4A is a surface image after dressing, and FIG. 4B is a surface image before starting use.

4C and 4D are surface images of the groove portion of the end face grinding wheel of Example 3-2. FIG. 4C is a surface image after dressing and FIG.

According to the surface image, it was confirmed that the condition of the surface of the groove was returned to the same level as that before the start of use after dressing in any grindstone.

This can also be confirmed from the fact that in Table 3, the measurement results of the groove surface of the grindstone after dressing recovered to almost the same level as before the start of use in terms of surface roughness Ra, protrusion amount and wear amount.

From the results of the above examples, it was confirmed that the dressing method for the end face grinding can be performed by the dressing method of the present embodiment regardless of the type and size of the glass substrate and the grindstone.

The dressing method of the grinding wheel for end face grinding of the glass substrate according to the present embodiment uses a glass substrate as a dressing material, makes the feed rate slower than that at the time of product manufacture, and increases the grinding amount (processing amount) than at the time of product manufacture. In this way, dressing is performed by supplying a glass substrate to the end face grinding apparatus. For this reason, it is possible to perform dressing without stopping the end surface grinding apparatus, and it is possible to improve the productivity as compared with the prior art, and it is not necessary for the operator to manually perform dressing, and dressing can be easily performed.

And, as in the conventional dressing method, the surface condition of the groove of the grindstone after dressing by the operator does not occur, and the processing ability of the grindstone can be stably recovered, and the surface of the groove formed on the grindstone Shape deformation can also be prevented.

Also, conventionally, when it was found that the surface shape of the groove formed in the grindstone was inadequate after being installed in the end face grinding apparatus, it was necessary to stop the end face grinding apparatus and replace the grindstone. However, even in such a case, by performing the dressing method of the present embodiment, it is possible to eliminate the deficiencies in the surface shape of the grooves without stopping the end face grinding apparatus. Increase productivity.

The preferred embodiments and examples of the present invention have been described in detail above. However, the present invention is not limited to the specific embodiments and examples described above, and is based on the gist of the present invention described in the claims. Various modifications and changes can be made within the range.

This international application claims priority based on Japanese Patent Application No. 2012-005649 filed on January 13, 2012, the entire contents of which are incorporated herein by reference.

Claims

A method for dressing a grinding wheel for grinding an end face of a glass substrate,
Using a glass substrate as a dressing material,
The feed rate of the glass substrate used as a dressing material is slower than the feed rate of the glass substrate when the end surface is ground during product production,
The amount of grinding of the glass substrate used as a dressing material is larger than the amount of grinding of the glass substrate when the end surface is ground during product production.
A method for dressing a grindstone for grinding an end face of a glass substrate, wherein the glass substrate used as a dressing material is supplied to the grindstone for end face grinding.
The feed rate of the glass substrate used as a dressing material is 1/6 or more and 1/3 or less of the feed rate of the glass substrate when the end surface is ground during product production,
The grinding amount of the glass substrate used as a dressing material is 1.1 times or more and 3.5 times or less of the grinding amount of the glass substrate when the end surface is ground during product manufacture. A method for dressing a grindstone for grinding an end face of a glass substrate as described.
The glass substrate used as a dressing material is
3. The method for dressing a grindstone for grinding an end face of a glass substrate according to claim 1, wherein the end face grinding process is performed on the glass substrate.
The said glass substrate used as a dressing material is used as a product, The dressing method of the grindstone for end surface grinding of the glass substrate as described in any one of Claim 1 thru | or 3 characterized by the above-mentioned.
At the time of product manufacture, a normal process of grinding the end surface of the glass substrate with a first grinding amount while feeding the glass substrate to the end surface grinding wheel at a first feed rate;
Determining whether or not dressing of the grinding wheel for end face grinding is necessary at a predetermined timing; and
When it is determined that the dressing is necessary, the glass substrate is fed to the end grinding grindstone at a second feed rate that is slower than the first feed rate, and the first grinding amount is larger than the first grinding amount. A dressing step of grinding the end surface of the glass substrate with a grinding amount of 2,
The manufacturing method of the glass substrate containing this.
The method for producing a glass substrate according to claim 5, wherein the normal process is performed again after performing the dressing process for a predetermined time.
Continuously sending a plurality of glass substrates to the end surface grinding wheel,
The method for producing a glass substrate according to claim 5 or 6, wherein the step of determining is performed each time the normal step is performed on a predetermined number of the glass substrates.
8. Any one of claims 5 to 7, wherein, in the step of judging, when the cumulative grinding amount of the glass substrate after the last dressing step is equal to or more than a set value, it is judged that dressing of the grindstone for end face grinding is necessary. A method for producing a glass substrate according to claim 1.