JP2016108186A - Method and apparatus for cutting glass plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus for cutting a glass plate, capable of cutting the glass plate having first and second main surfaces along a cutting scheduled line.SOLUTION: An apparatus 1 for cutting a glass plate 10 comprises: first holding means, such as an upstream side roller set 3 for partially holding the glass plate 10 in the state of curving the glass plate 10 so that a curvature on the side of the second main surface 10b is smaller than that on the side of the first main surface 10a in a stress overlapping area A1 served as a certain area along the cutting scheduled line 7 of the glass plate 10; and heating means, such as a laser light source 2 for locally heating the first main surface 10a of the stress overlapping area A1 so as to generate tensile heat stress on the side of the second main surface 10b of the stress overlapping area A1 or cooling means for locally cooling the second main surface 10b of the stress overlapping area A1.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an apparatus and a method for cleaving a glass plate (glass sheet).

  Conventionally, when a glass plate is cut, a scribe line (cut / shallow groove) is formed along the planned cutting line (scribing), and mechanical or thermal stress is applied to the glass plate along the scribe line. A method of breaking a glass plate by adding is generally used.

  In particular, in the field of FPD (Flat Panel Display) such as LCD glass and cover glass, it is desired that there is no contamination of the glass surface by dust such as shavings and fine chips (cullet) generated when cutting a glass plate. . Therefore, in recent years, glass processing using laser light with less contamination of the glass surface is becoming widespread.

  For example, in Patent Document 1, a glass plate is adsorbed and restrained on a fixed base in a curved state, and a convex portion of the glass plate is locally heated with a laser beam to generate a compressive stress in the heated portion and heated immediately thereafter. It is described that a tensile stress is generated by cooling the portion with a cooling medium, and the crack is propagated from the trigger crack of the glass plate by the action of the tensile stress.

  In addition, for example, in Patent Document 2, a scribe line along a cutting plan line is formed on a glass plate using UV laser light, and thermal distortion is given to the glass plate with carbon dioxide laser light along the scribe line. According to this, it is described that the glass plate is cut along the cutting plan line.

JP 2012-61681 A JP-A-5-32428

  In the processing method of Patent Document 1, the glass plate is adsorbed on a fixed base, the glass plate is locally heated with a laser beam, and the heated portion is immediately cooled with a cooling medium. For this purpose, a device that realizes this processing method requires a fixing base having a suction mechanism, a laser light generator, and a device for injecting a cooling medium.

  In the processing method described in Patent Document 2, since a plurality of steps including a step of forming a scribe line on the glass plate and a step of applying thermal stress to the glass plate are performed, time is required for the processing. Further, in order to form a scribe line on a glass plate, a laser beam having sufficient energy for evaporating and scattering the glass component is necessary. Therefore, compared with a laser beam generator for applying thermal stress to a glass plate, a laser beam generator for forming a scribe line on the glass plate is expensive, and a processing apparatus including both of these laser beam generators Tends to be expensive.

  This invention is made | formed in view of the above situation, Comprising: It is a glass plate cleaving apparatus and method, Comprising: While suppressing the cost increase of an apparatus, the reduction | decrease of the contamination of a glass surface and the reduction of a processing man-hour are implement | achieved. The purpose is to provide things.

The method for cleaving a glass plate according to one aspect of the present invention is as follows.
A glass plate cleaving method for cleaving a glass plate having a first main surface and a second main surface along a predetermined cleaving plan line,
Forming a starting point of the cutting plan line on the second main surface;
A certain region along the cutting plan line of the glass plate is a stress superimposed region, and the glass has a curvature on the second principal surface side smaller than a curvature on the first principal surface side in the stress superimposed region. Generating a compressive bending stress on the first main surface side of the stress superimposed region and generating a tensile bending stress on the second main surface side by curving the plate;
The second principal surface side of the stress superimposed region by locally cooling the second principal surface side of the stress superimposed region or locally heating the first principal surface side of the stress superimposed region. Generating tensile thermal stress in the
It is characterized by including.

Moreover, the cleaving device for a glass plate according to one aspect of the present invention,
A cleaving device for cleaving a glass plate having a first main surface and a second main surface along a predetermined cleaving plan line,
A certain region along the cutting plan line of the glass plate is a stress superimposed region, and the glass has a curvature on the second principal surface side smaller than a curvature on the first principal surface side in the stress superimposed region. A first holding means for partially holding the glass plate in a curved state;
Heating means for locally heating the first main surface of the stress superimposed region or the second main surface of the stress superimposed region so as to generate a tensile thermal stress on the second main surface side of the stress superimposed region. And a cooling means for locally cooling.

  In the glass plate cleaving method and the glass plate cleaving apparatus, the tensile bending stress and the tensile thermal stress generated on the second principal surface side of the stress superimposing region of the glass plate are superimposed to reach the breaking stress of the glass plate. Cracks develop from the starting point of the plate and eventually the glass plate breaks. According to this method and apparatus, since the scribing of the glass plate 10 along the cutting plan line 7 is not required, the glass surface is less contaminated with glass waste than when scribing is performed, and the processing man-hours and apparatus are reduced. Cost reduction can be realized. Further, in order to generate a tensile thermal stress on the second principal surface side of the stress superimposed region of the glass plate, one of heating of the first principal surface of the stress superimposed region and cooling of the second principal surface of the stress superimposed region is performed. Therefore, it is sufficient to reduce processing man-hours and apparatus costs.

  ADVANTAGE OF THE INVENTION According to this invention, the glass plate cleaving method and glass plate cleaving apparatus which implement | achieve the reduction of the contamination of a glass surface and the reduction of a processing man-hour can be provided, suppressing the cost increase of an apparatus.

It is a side view which shows schematic structure of the cleaving apparatus of the glass plate which concerns on one Embodiment of this invention. It is a top view which shows schematic structure of the cleaving apparatus of a glass plate. It is an III-III arrow line view in FIG. 1 which shows an upstream roller set. It is sectional drawing of the glass plate for demonstrating the bending stress which arises in a glass plate by the effect | action of an upstream roller set. It is a VV arrow line view in FIG. 1 which shows a downstream roller set. It is sectional drawing of the glass plate for demonstrating the bending stress which arises in a glass plate by the effect | action of a downstream roller set.

  Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a side view showing a schematic configuration of a cleaving apparatus 1 for a glass plate 10 according to an embodiment of the present invention, and FIG. 2 is a plan view showing a schematic configuration of the cleaving apparatus 1 for a glass plate 10. The cleaving device 1 for the glass plate 10 shown in FIGS. 1 and 2 is a device that cleaves the glass plate 10 along a virtual cleaving plan line 7. The cutting plan line 7 is one or a combination of a straight line and a curve, and the cutting plan line 7 illustrated in FIG. 2 is a curve.

  The glass plate 10 to be cleaved by the cleaving device 1 is a thin plate of 2 mm or less, and a first main surface 10a to be irradiated with laser light, which will be described later, and a second main surface parallel to the first main surface 10a and facing the opposite side. Main surface 10b. In the present embodiment, since the two main surfaces 10a and 10b of the glass plate 10 are conveyed in the conveying direction 91 in a state in which they are oriented in the vertical direction, the first main surface 10a is the upper surface and the second main surface 10b is the lower surface. . However, the glass plate 10 may be conveyed so that both the first main surface 10a and the second main surface 10b face the horizontal direction.

  The cleaving device 1 is disposed on the downstream side in the transport direction 91 of the upstream roller set 3 and the upstream roller set 3 (an example of the first holding unit) disposed on the upstream side in the transport direction 91 of the glass plate 10. A downstream roller set 4 (an example of a second holding unit) and a laser light source 2 (an example of a heating unit) that irradiates the glass plate 10 with a laser beam 21 are provided. Hereinafter, each component of the cleaving apparatus 1 will be described in detail.

  First, the laser light source 2 will be described. The laser light source 2 is a local heat source that can locally heat the surface of the glass plate 10 and generate thermal stress in the glass plate 10. The laser light 21 oscillated from the laser light source 2 has a remarkably high absorption rate with respect to the glass material, and is absorbed at the extreme surface of the glass plate 10 when irradiated to the glass plate 10. Such laser light 21 is laser light in the ultraviolet region and infrared region. The laser beam 21 according to the present embodiment is a carbon dioxide laser beam that is one of laser beams in the infrared region.

  Next, the upstream roller set 3 will be described. 3 is a view taken along the line III-III in FIG. 1 showing the upstream roller set 3, and FIG. 4 is a cross-sectional view of the glass plate 10 for explaining the bending stress generated in the glass plate 10 by the action of the upstream roller set 3. FIG. As shown in FIGS. 1 to 4, the upstream roller set 3 includes a plurality of rollers 31, 32, 33, and 34 that are arranged in a roller axial direction 92 that is a horizontal direction orthogonal to the conveying direction 91 in plan view. Yes. The plurality of rollers of the upstream roller set 3 includes a pair of upper rollers 31 and 32 and a pair of lower rollers 33 and 34. However, the upstream roller set 3 may include other rollers.

  The pair of upper rollers 31 and 32 are disposed coaxially and have the same roller diameter. In the present embodiment, the upper rollers 31 and 32 function as a transport unit that transports the glass plate 10 in the transport direction 91. For this purpose, the upper rollers 31 and 32 are rotationally driven by a driving device 35 including a motor, a speed reduction mechanism, a power transmission mechanism and the like (not shown). The upper rollers 31 and 32 rotate while contacting the first main surface 10 a of the glass plate 10, whereby the glass plate 10 is sent out in the transport direction 91.

The pair of upper rollers 31 and 32 are spaced apart from each other in the roller axial direction 92, and a gap 36 in the roller axial direction 92 is provided between the upper rollers 31 and 32 (between the contact points P ₃₁ and P ₃₂ ). Existing. The laser light irradiation point 22 is located in the gap 36 in plan view, and the laser light 21 oscillated from the laser light source 2 passes through the gap 36.

  The pair of lower rollers 33 and 34 are arranged so as to sandwich the upper rollers 31 and 32 from both sides in the roller axial direction 92. These lower rollers 33 and 34 are coaxially arranged and have the same roller diameter. The lower rollers 33 and 34 are in contact with the second main surface 10 b of the glass plate 10 and rotate as the glass plate 10 moves.

  As shown in FIG. 4, the upstream roller set 3 configured as described above has a curvature radius of the first main surface 10 a smaller than a curvature radius of the second main surface 10 b in the stress superimposed region A1 of the glass plate 10. The glass plate 10 is partially held in a state in which the glass plate 10 is curved with the stress superimposed region A1 as a vertex. Here, the stress superimposed region A1 of the glass plate 10 is one region along the cutting plan line 7 of the glass plate 10, and a part of the cutting plan line 7 is included in the stress superimposed region A1.

More specifically, the upper roller 31 is in contact with the first major surface 10a of the glass plate 10 at the contact point P _31, which grants the thickness direction downward pressing force F ₃₁ on the glass plate 10. Similarly, the upper roller 32 is in contact with the first major surface 10a of the glass plate 10 at the contact point P _32, the glass plate 10 is imparted a downward pressing force F _32. The lower roller 33 is in contact with the second major surface 10b of the glass plate 10 at the contact point P _33, the glass plate 10 is imparted an upward pressing force F _33. Likewise, the lower roller 33 is in contact with the second major surface 10b of the glass plate 10 at the contact point P _34, the glass plate 10 is imparted an upward pressing force F _34. These contact points P ₃₁ , P ₃₂ , P ₃₃ , P ₃₄ are aligned on the same straight line in the roller axial direction 92 in plan view, and these contact points P ₃₁ , P ₃₂ , P ₃₃ , P ₃₄ are The cross section of the glass plate 10 that is included has a curved shape that is bent downward with the point between the contact points P ₃₁ and P ₃₂ as the lowest point. Incidentally, the vertical position of the lower roller 33, 33 is adjustable, the point of contact _{P 31, P 32, P 33} , P 34 the contact point P ₃₃ so that the cross section of the glass plate 10 is bent downward containing, P ₃₄ The position is adjusted.

  Due to the action of the upstream roller set 3, the glass plate 10 is curved so as to protrude downward with the stress superimposed region A 1 as a vertex, and is compressed toward the first main surface 10 a side of the stress superimposed region A 1 of the glass plate 10. A bending stress is generated, and a tensile bending stress is generated on the second principal surface 10b side of the stress superimposed region A1.

  Next, the downstream roller set 4 will be described. FIG. 5 is a view taken along the line IV-IV in FIG. 1 showing the downstream roller set 4, and FIG. 6 is a cross-sectional view of the glass plate 10 for explaining bending stress generated in the glass plate 10 due to the action of the downstream roller set 4. FIG. As shown in FIGS. 1, 2, 5, and 6, the downstream roller set 4 includes a plurality of rollers 41, 42, 43, 44 arranged in a roller axial direction 92 that is a horizontal direction orthogonal to the transport direction 91 in a plan view. It is comprised by. The plurality of rollers of the downstream roller set 4 includes a pair of lower rollers 41 and 42 and a pair of upper rollers 43 and 44. However, the downstream roller set 4 may include other rollers.

  The pair of lower rollers 41 and 42 are arranged coaxially and have the same roller diameter. In the present embodiment, the upper roller 31 of the upstream roller set 3 and the lower roller 41 of the downstream roller set 4 are aligned in the conveying direction 91, and the upper roller 32 of the upstream roller set 3 and the lower roller of the downstream roller set 4. These rollers are arranged so that 42 is aligned in the transport direction 91. Further, the distance D2 between the rotation shafts (axial centers) of the upper rollers 31 and 32 of the upstream roller set 3 and the rotational shafts (axial centers) of the lower rollers 41 and 42 of the downstream roller set 4 in the conveying direction 91 is D2. Just away.

  In the present embodiment, the lower rollers 41 and 42 function as a transport unit that transports the glass plate 10 in the transport direction 91. For this purpose, the lower rollers 41 and 42 are rotationally driven by a driving device 45 including a motor, a speed reduction mechanism, a power transmission mechanism and the like (not shown). The lower rollers 41 and 42 rotate while contacting the second main surface 10 b of the glass plate 10, whereby the glass plate 10 is sent out in the transport direction 91. In this embodiment, both the upper rollers 31 and 32 of the upstream roller set 3 and the lower rollers 41 and 42 of the downstream roller set 4 function as conveyance rollers, and the glass plate 10 moves 200 to 300 mm in the conveyance direction 91. These transport rollers rotate synchronously so as to move at a speed of / sec. However, the inner roller of either the upstream roller set 3 or the downstream roller set 4 may be configured to function as a transport roller.

  The pair of upper rollers 43 and 44 are arranged so as to sandwich the pair of lower rollers 41 and 42 from both sides in the roller axial direction 92. The upper rollers 43 and 44 are disposed coaxially and have the same roller diameter. The upper rollers 43 and 44 are in contact with the first main surface 10 a of the glass plate 10 and rotate as the glass plate 10 moves. In this embodiment, the lower roller 33 of the upstream roller set 3 and the upper roller 43 of the downstream roller set 4 are aligned in the transport direction 91, and the lower roller 34 of the upstream roller set 3 and the upper roller of the downstream roller set 4. These rollers are arranged in such a manner that 44 is aligned in the transport direction 91.

  As shown in FIG. 6, the downstream roller set 4 has the glass plate 10 such that the curvature radius of the first main surface 10 a is larger than the curvature radius of the second main surface 10 b in the stress reversal region A <b> 2 of the glass plate 10. Is bent partially with the stress reversal region A2 as a vertex, and the glass plate 10 is partially held. Here, the stress reversal region A2 of the glass plate 10 is one region away from the stress superposition region A1 of the glass plate 10 in the crack propagation direction. In addition, when the cutting plan line 7 includes a curve with a small radius of curvature, the stress reversal region A2 may not be along the cutting plan line 7.

More specifically, the lower roller 41 is in contact with the second major surface 10b of the glass plate 10 at the contact point P _41, the glass plate 10 is imparted an upward pressing force F _41. Likewise, the lower roller 42 is in contact with the second major surface 10b of the glass plate 10 at the contact point P _42, the glass plate 10 is imparted an upward pressing force F _42. The upper roller 43 is in contact with the first major surface 10a of the glass plate 10 at the contact point P _43, the glass plate 10 is imparted a downward pressing force F _43. Similarly, the upper roller 43 is in contact with the first major surface 10a of the glass plate 10 at the contact point P _44, the glass plate 10 is imparted a downward pressing force F _44. These contact points P ₄₁ , P ₄₂ , P ₄₃ , P ₄₄ are aligned on the same straight line in the roller axial direction 92 in plan view, and these contact points P ₃₁ , P ₃₂ , P ₃₃ , P ₃₄ are The cross section of the glass plate 10 that is included has a curved shape that is bent upward with the point between the contact points P ₄₁ and P ₄₂ as the uppermost point. Incidentally, the vertical position of the upper roller 43 is adjustable, the point of contact _{P 41, P 42, P 43} , the contact point so that the cross section is upwardly bent of the glass plate 10 including the P ₄₄ P _43, P ₄₄ The position is adjusted.

  Due to the action of the downstream roller set 4, the glass plate 10 is curved so as to protrude upward with the stress reversal region A 2 as a vertex, and a tensile bending stress is applied to the first principal surface 10 a side of the stress reversal region A 2 of the glass plate 10. As a result, a compressive bending stress is generated on the second principal surface 10b side of the stress reversal region A2. That is, in the stress superimposed region A1 and the stress reversal region A2, the side where the tensile bending stress is generated and the side where the compressive bending stress is generated are reversed between the first main surface 10a side and the second main surface 10b side. It has become.

  Here, the cleaving process of the glass plate 10 by the cleaving apparatus 1 having the above configuration will be described.

  First, when the cleaving process of the glass plate 10 is started, as shown in FIG. 2, the tensile bending stress is applied to the second main surface 10 b side of the end surface 10 c where the crack of the glass plate 10 is initially generated (that is, in the stress overlapping region A <b> 1). A dotted or short-line-shaped starting point scribing 71 is formed on the main surface on the side where it occurs. The starting point 71 may be, for example, a score line of about 1 to 2 mm formed on the side of the second main surface 10b of the end surface 10c of the glass plate 10, a notch, or the like. The starting rod 71 can be processed into the glass plate 10 using a laser beam, a cutting tool, or the like.

Next, the glass plate 10 is introduced between the upper and lower rollers 43 and 44 and the lower rollers 41 and 42 of the downstream roller set 4 so that the upper rollers 31 and 32 and the downstream side of the upstream roller set 3 serving as conveyance rollers are disposed. The lower rollers 41 and 42 of the roller set 4 are driven to rotate. These conveyance rollers rotate in the direction in which the glass plate 10 is conveyed in the conveyance direction 91 in synchronization. Then, the end face 10c of the glass plate 10 moves in the transport direction 91 and is guided between the upper and lower rollers 31, 32 and the lower rollers 33, 34 of the upstream roller set 3. Here, between the contact points P ₃₂ fracture feature line 7 and the contact point P ₃₁ (i.e., between the upper rollers 31, 32) so as to pass through the laser beam irradiation point 22 of the glass plate 10 is guided.

  As described above, by causing both the upstream roller set 3 and the downstream roller set 4 to act on the glass plate 10, as shown in FIG. 1 and FIG. Compressive bending stress is generated on the main surface 10a side, and tensile bending stress is generated on the second main surface 10b side. Further, as shown in FIGS. 1 and 6, in the stress reversal region A2 of the glass plate 10, tensile bending stress is generated on the first main surface 10a side and compressive bending stress is generated on the second main surface 10b side.

  Then, the laser beam 21 is irradiated to the glass plate 10 in the stress state as described above. The laser beam irradiation point 22 is the surface on the first principal surface 10a side of the stress superimposed region A1 of the glass plate 10, that is, the surface on the side where compressive bending stress is generated. In the present embodiment, the laser beam irradiation point 22 is located at a position away from the pair of upper rollers 31 and 32 of the upstream roller set 3 by a distance D1 upstream in the conveyance direction 91 of the glass plate 10. Yes. That is, the laser beam irradiation point 22 is the stress superimposing region A1, and the compressive bending stress is generated on the first main surface 10a side of the glass plate 10 by the action of the upstream roller set 3, and the tensile force is applied on the second main surface 10b side. It suffices to be within a range where bending stress is generated. The laser beam 21 is preferably a focused laser beam focused at the laser beam irradiation point 22, and the cross-sectional shape of the laser beam 21 focused at the laser beam irradiation point 22 is the cutting plan line 7 (that is, a glass plate). It is further desirable to have an elliptical shape that is long along 10 transport directions 91). That is, it is desirable that the local heating range on the glass plate 10 by the laser light source 2 (heating means) has a longitudinal direction along the cutting plan line 7 and a lateral direction orthogonal to the longitudinal direction.

  The laser beam 21 irradiated on the glass plate 10 is absorbed by the first main surface 10a of the glass plate 10, whereby the first main surface 10a is locally heated. Thereby, a big temperature gradient (temperature difference) is formed between the 1st main surface 10a of the glass plate 10, and the 2nd main surface 10b. Since the stress superimposed region A1 of the glass plate 10 is almost constrained by the pair of upper rollers 31, 32, compressive thermal stress due to thermal expansion is generated on the first main surface 10a of the stress superimposed region A1. The tensile thermal stress due to the reaction force of thermal expansion is generated on the second main surface 10b of the stress superimposed region A1.

  Eventually, when the tensile bending stress and the tensile thermal stress generated on the second principal surface 10b side are superimposed in the stress superimposing region A1 of the glass plate 10 to reach the fracture stress, the starting point 71 formed on the second principal surface 10b. The crack progresses along the cutting plan line 7. In other words, the glass plate 10 is superposed on the brittle fracture stress by superimposing the thermal stress caused by the temperature difference between the front and back surfaces by heating with the laser beam 21 and the stress caused by the bending force applied to the glass plate 10 by the upstream roller set 3. And cracks occur. It should be noted that by starting the starting plate 71 in advance on the glass plate 10, it is possible to control the starting point of the crack, and since stress concentration occurs at the starting plate 71, the crack can be advanced with smaller stress. .

  A stress reversal region A2 exists in the direction in which cracks generated in the stress superimposed region A1 of the glass plate 10 propagate. In this stress reversal region A2, the stress opposite to that of the stress superimposed region A1, that is, the tensile bending stress is generated on the first main surface 10a side of the glass plate 10 and the compressive bending stress is generated on the second main surface 10b side. The progress of cracks generated in the glass plate 10 stops between the stress superimposed region A1 and the stress reversal region A2.

  And if the glass plate 10 is conveyed so that the stress superimposition area | region A1 moves on the glass plate 10 along the cutting plan line 7, a crack can be advanced along the cutting plan line 7, As a result The glass plate 10 can be cleaved along the cleaving line 7.

  As explained above, in the cleaving method of the glass plate 10 according to the present embodiment, the starting point 71 of the cleaving plan line 7 is formed on the second main surface 10b of the glass plate 10, and the stress overlap region A1 of the glass plate 10 is formed. , The glass plate 10 is curved so that the curvature on the second main surface 10b side is smaller than the curvature on the first main surface 10a side, thereby generating a compressive bending stress on the first main surface 10a side of the stress overlapping region A1. And generating a tensile bending stress on the second main surface 10b side and locally heating the first main surface 10a side of the stress superimposed region A1 to the second main surface 10b side of the stress superimposed region A1. Generating a tensile thermal stress. Here, the stress superimposed region A1 of the glass plate 10 is a certain region along the cutting plan line 7 of the glass plate 10.

  Moreover, the cleaving apparatus 1 for the glass plate 10 according to the present embodiment bends the glass plate 10 so that the curvature on the second main surface 10b side is smaller than the curvature on the first main surface 10a side in the stress superimposed region A1. In such a state, the upstream roller set 3 (an example of the first holding means) that partially holds the glass plate 10 and the stress so as to generate a tensile thermal stress on the second main surface 10b side of the stress superimposed region A1. A laser light source 2 (an example of a heating unit) that locally heats the first main surface 10a of the overlapping region A1 is provided.

  According to the cleaving method and the cleaving apparatus 1 for the glass plate 10, the tensile bending stress and the tensile thermal stress generated on the second main surface 10b side of the stress superimposing region A1 of the glass plate 10 are superimposed to break the glass plate 10. It reaches stress, a crack progresses from the starting point 71 of the glass plate 10, and the glass plate 10 breaks soon. In this method and apparatus, the scribing process (namely, the formation process of the scribe line along the cutting plan line 7) performed when cleaving the conventional glass plate 10 can be omitted. Therefore, a scribing device is not necessary, and an increase in the cost of the cleaving device 1 can be suppressed. Further, contamination of the glass surface due to the glass dust generated at the time of forming the scribe line can be suppressed, and a cleaning device for removing the glass dust by cleaning becomes unnecessary. Furthermore, since the fracture surface of the glass plate 10 is very smooth and free from chipping, a glass processed product that has high strength and does not require chamfering is obtained.

  Moreover, according to the said method and apparatus, in order to generate | occur | produce a tensile thermal stress to the 2nd main surface 10b side of the stress superimposition area | region A1 of the glass plate 10, only heating the 1st main surface 10a of the stress superimposition area | region A1. Therefore, it is possible to reduce the number of processing steps and the apparatus cost.

  Moreover, in the cleaving method of the glass plate 10 according to the present embodiment, a tensile bending stress is further generated on the first main surface 10a side of the stress reversal region A2 of the glass plate 10 and a compressive bending stress is generated on the second main surface 10b side. Is generated. Here, the stress reversal region A2 of the glass plate 10 is a region away from the stress superimposed region A1 in the crack propagation direction.

  Similarly, in the cleaving apparatus 1 for the glass plate 10 according to the present embodiment, the glass plate 10 is curved so that the curvature on the second main surface 10b side is larger than the curvature on the first main surface 10a side in the stress reversal region A2. In this state, a downstream roller set 4 (second holding means) that partially holds the glass plate 10 is further provided.

  According to the above method and apparatus, the stress reversal region A <b> 2 exists in the direction of propagation of cracks generated in the glass plate 10. In the stress reversal region A2, a stress opposite to that of the stress overlapping region A1, that is, a tensile bending stress is generated on the first main surface 10a side of the glass plate 10 and a compressive bending stress is generated on the second main surface 10b side. Due to such a stress state, the progress of the cracks generated in the glass plate 10 stops between the stress overlapping region A1 and the stress reversal region A2. Therefore, it is possible to control the direction and extent (speed) of the crack generated from the stress superimposed region A1. Even when the shape of the cutting plan line 7 is a curve, cracks in the direction away from the cutting plan line 7 are difficult to enter, so that it is possible to cut a complicated shape including a curve, and the yield is also high. Good. Thus, since the progress of the crack can be controlled, the glass plate 10 can be cut along the cutting plan line 7 having a complicated shape including a curve. In the technique described in Patent Document 1, since a bending strain generation region is wide and a thermal stress is given by a point, a crack is allowed to progress along a cutting plan line, or the degree (speed) of the progress is controlled. It is difficult to do.

  Moreover, in the cutting method of the glass plate 10 which concerns on this embodiment, conveying the glass plate 10 so that the stress superimposition area | region A1 may move along the cutting plan line 7 is further included. Similarly, in the cleaving apparatus 1 for the glass plate 10 according to the present embodiment, the upstream roller set 3 that conveys the glass plate 10 so that the stress superimposed region A1 moves on the glass plate 10 along the cleaving plan line 7. And a downstream roller set 4 (an example of a conveying unit).

  According to the said method and apparatus, a crack can be advanced along the desired cutting plan line 7, and the glass plate 10 can be cut along the cutting plan line 7. FIG.

  Moreover, in the cleaving apparatus 1 of the glass plate 10 which concerns on this embodiment, as a means to heat the 1st main surface 10a of the stress superimposition area | region A1, an ultraviolet region or an infrared region of the 1st main surface 10a of the stress superimposition area | region A1 is carried out. A laser oscillation device (laser light source 2) for irradiating laser light is provided. As such a laser oscillation apparatus, a carbon dioxide laser oscillation apparatus used as a laser light source in a conventional cleaving apparatus can be used. Since the carbon dioxide laser oscillation device has a low output as compared with a laser light source used for scribing, an increase in the cost of the cleaving device 1 can be suppressed.

  Moreover, in the cleaving apparatus 1 of the glass plate 10 which concerns on this embodiment, the 1 or more roller (upper rollers 31 and 32) rotated while contacting the 1st main surface 10a of the glass plate 10, and the 2nd main surface 10b. The first holding means for partially holding the glass plate 10 in a state where the stress overlapping region A1 of the glass plate 10 is curved is constituted by one or more rollers (lower rollers 33, 34) that rotate while contacting with each other. ing. Similarly, in the cleaving apparatus 1 for the glass plate 10 according to the embodiment, one or more rollers (upper rollers 43 and 44) that rotate while being in contact with the first main surface 10a and the second main surface 10b are in contact. A second holding means for partially holding the glass plate 10 in a state where the stress reversal region A2 of the glass plate 10 is curved is constituted by one or more rotating rollers (lower rollers 41 and 42).

  According to the said apparatus, the said glass plate 10 can be hold | maintained in the state which generate | occur | produced the predetermined stress state in the glass plate 10, without the movement of the glass plate 10 being inhibited.

  Further, in the stress superimposed region A1, one or more rollers that rotate while being in contact with the first main surface 10a are separated from a pair of rollers (upper rollers 31, 32) arranged on both sides across the cutting plan line 7. The laser light (heat) supply path from the laser light source 2 which is an example of a heating means is provided between the pair of rollers (upper rollers 31, 32). Thereby, the structure which makes the vertex of the glass plate 10 curved in the stress superimposition area | region A1 and the laser beam irradiation point 22 approach can be implement | achieved easily.

  Although the preferred embodiment of the present invention has been described above, the above configuration can be changed as follows, for example.

  In the above embodiment, in order to generate a tensile thermal stress on the second principal surface 10b side of the stress superimposed region A1 of the glass plate 10, the surface of the first principal surface 10a of the stress superimposed region A1 is locally applied by the laser beam 21. Heating. However, the method for generating the tensile thermal stress on the second principal surface 10b side of the stress superimposed region A1 of the glass plate 10 is not limited to the method according to the above embodiment.

  For example, a spot heater may be used as a heating unit that locally heats the surface of the first main surface 10a of the stress superimposed region A1. In this case, the spot heater and the glass plate 10 may or may not contact each other. A heating roller may be used as the heating means. When using these heating means, a heating means may be provided in the gap between the upper rollers 31 and 32 of the upstream roller set 3. In addition, as for the local heating range on the glass plate 10 by these heating means, it is desirable to have the longitudinal direction along the cutting plan line 7, and the transversal direction orthogonal to the said longitudinal direction.

  For example, the surface of the second principal surface 10b of the stress superimposed region A1 of the glass plate 10 is locally cooled, and between the first principal surface 10a and the second principal surface 10b of the stress superimposed region A1 of the glass plate 10 By generating a temperature difference (temperature gradient), a tensile thermal stress may be generated on the second main surface 10b side of the stress superimposed region A1. In this case, in order to locally cool the surface of the second main surface 10b of the stress superimposed region A1 of the glass plate 10, a cold heat source storing a cryogenic gas such as liquid nitrogen and the cryogenic gas are applied to the stress superimposed region A1. The nozzle that blows on the second main surface 10b may be provided in the cleaving device 1 in place of the laser light source 2 as a cooling means.

  In the above embodiment, some rollers of the upstream roller set 3 and the downstream roller set 4 that are the holding means for the glass plate 10 are used as the conveying means, but the upstream roller set 3 and the downstream roller are used. In addition to the set 4, a conveyance roller may be separately provided.

  Moreover, in the said embodiment, all the holding means of the glass plate 10 are comprised with the roller. Thereby, the advantage that the glass plate 10 can be partially held in a state where the glass plate 10 is curved toward the first main surface 10a side or the second main surface 10b side without hindering the movement of the glass plate 10. There is. However, the holding means for the glass plate 10 is not limited to being composed entirely of rollers, and instead of some of the rollers, a block having a surface with a small friction coefficient with the glass plate 10 may be used.

A1 Stress superposition region A2 Stress reversal region 1 Cleaving device 2 Laser light source (an example of heating means)
3 Upstream roller set (an example of first holding means)
31, 32 Upper roller 33, 34 Lower roller 4 Downstream roller set (an example of second holding means)
41, 42 Lower roller 43, 44 Upper roller 7 Cut line 71 Starting point 10 Glass plate 10a First main surface 10b Second main surface 91 Conveying direction 92 Roller axial direction

Claims (12)

A glass plate cleaving method for cleaving a glass plate having a first main surface and a second main surface along a predetermined cleaving plan line,
Forming a starting point of the cutting plan line on the second main surface;
A certain region along the cutting plan line of the glass plate is a stress superimposed region, and the glass has a curvature on the second principal surface side smaller than a curvature on the first principal surface side in the stress superimposed region. Generating a compressive bending stress on the first main surface side of the stress superimposed region and generating a tensile bending stress on the second main surface side by curving the plate;
The second principal surface side of the stress superimposed region by locally cooling the second principal surface side of the stress superimposed region or locally heating the first principal surface side of the stress superimposed region. Generating tensile thermal stress in the
A method of cleaving a glass plate including   A region away from the stress superimposing region of the glass plate in the crack propagation direction is used as a stress reversal region, and tensile bending stress is generated on the first main surface side of the stress reversal region and compressed on the second main surface side. The method for cleaving a glass plate according to claim 1, further comprising generating a bending stress.   The method of cleaving a glass sheet according to claim 1 or 2, further comprising conveying the glass sheet so that the stress superimposed region moves along the cleaving plan line. A cleaving device for cleaving a glass plate having a first main surface and a second main surface along a predetermined cleaving plan line,
A certain region along the cutting plan line of the glass plate is a stress superimposed region, and the glass has a curvature on the second principal surface side smaller than a curvature on the first principal surface side in the stress superimposed region. A first holding means for partially holding the glass plate in a curved state;
Heating means for locally heating the first main surface of the stress superimposed region or the second main surface of the stress superimposed region so as to generate a tensile thermal stress on the second main surface side of the stress superimposed region. Cooling means for locally cooling,
A cleaving apparatus for glass plates.   A region away from the stress superimposed region in the crack propagation direction is defined as a stress reversal region, and the curvature of the second main surface side of the glass plate is larger than the curvature of the first main surface side in the stress reversal region. The glass plate cleaving apparatus according to claim 4, further comprising second holding means for partially holding the glass plate in a state where the glass plate is bent into a bent shape.   The cleaving apparatus for a glass plate according to claim 4 or 5, further comprising conveying means for conveying the glass plate so that the stress superimposed region moves on the glass plate along the cutting plan line.   The cleaving of the glass plate according to any one of claims 4 to 6, wherein the heating means is a laser oscillation device that irradiates the first main surface of the stress superimposed region with laser light in an ultraviolet region or an infrared region. apparatus.   The glass plate cleaving apparatus according to any one of claims 4 to 6, wherein the heating means is a spot heater.   The said 1st holding means is comprised by the 1 or more roller rotated while contacting the said 1st main surface, and the 1 or more roller rotated while contacting the said 2nd main surface. The glass plate cleaving apparatus according to any one of 8.   The one or more rollers that rotate while being in contact with the first main surface are composed of a pair of rollers arranged on both sides across the cutting plan line, and the heating unit or the heating unit is interposed between the pair of rollers. The glass plate cleaving apparatus according to claim 9, wherein a supply path for heat from the glass plate is provided.   The said 2nd holding means is comprised by the 1 or more roller rotated while contacting the said 1st main surface, and the 1 or more roller rotated while contacting the said 2nd main surface. The glass plate cleaving apparatus described.   The local heating range on the said glass plate by the said heating means has a longitudinal direction along the said cutting plan line, and the transversal direction orthogonal to the said longitudinal direction, It is any one of Claims 4-11. Glass plate cleaving device.

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