Patent Publication Number: US-8540551-B2

Title: Glass edge finish system, belt assembly, and method for using same

Description:
TECHNICAL FIELD 
     The present invention relates in general to the glass manufacturing field and, in particular, to a glass edge finishing system, a belt assembly and a method for finishing an edge of a glass sheet. 
     BACKGROUND 
     Sheet glass manufacturing requires three steps, melting of raw material, forming the melted glass into the proper shape which in this case is thin glass sheets (e.g., 3 mm thick or less), and finally shaping the thin glass sheets into a final shape which is satisfactory for the user of the glass sheets. The final shaping step includes separating near net shaped thin glass sheets from the glass ribbon, sizing the thin glass sheets through a cutting operation and edging the thin glass sheets to strengthen the thin glass sheets for handling operations. The discussion herein relates to the edging of the thin glass sheets. 
     Thin glass sheet edging is typically done today by utilizing a grinding wheel which has groove(s) formed therein. The formed groove(s) create a shape on the edge of the thin glass sheet that mirrors the groove. Unfortunately, there are several problems with using a grinding wheel to edge the thin glass sheets. A list of several of these problems follows: 
     1. Producing a consistent formed groove in the grinding wheel is becoming increasingly difficult due to the thinner glass sheets. 
     2. The grinding wheel&#39;s formed groove becomes misshapen with use causing an inconsistent edge shape in the glass sheet. 
     3. The surface area being used by the grinding wheel is limited to the formed groove which increases the cost due to the poor utilization of material. 
     4. The relatively small area of the grinding wheel which can come into contact with the edge of the glass sheet necessitates the use of coarser grain sizes which ultimately results in a poorer surface finish on the edge of the glass sheet. 
     5. The edge polishing process is unable to remove major flaws in the edge of the glass sheet which are generated during the cutting process and limits the strength of the edge of the glass sheet. 
     6. The lack of chip clearance between the glass sheet and the grinding wheel during the grinding process increases the potential for causing defects in the glass sheet due to the grinding wheel becoming clogged by chips (e.g., glass particles) from the glass sheet. 
     7. Particulates (e.g., chips, glass particles) can be imbedded within the grinding wheel&#39;s grooves which can limit the effectiveness of the grinding wheel. 
     8. Improvements to edge finish smoothness requires a multi-step process of grinding wheels each with a separate motor-spindle requirement that increases cost, process losses and are difficult to setup. 
     9. The edge of the glass sheet after grinding (polishing) is not smooth enough to prevent particle trapping, which could contribute significantly to an undesirable surface particle count due to late particle release. 
     10. The grinding wheel process requires a large amount of stock (80 um to 200 um) to remove the scoring defects in the glass sheet. This generates a large amount of particles which contaminate and adhere to the surfaces of the glass sheet and require an expensive washing process to clean the surfaces of the glass sheet. 
     As stated above the current process of edging a thin glass sheet using the grinding wheel has several drawbacks, specifically when it comes to edge strength or in another term the durability of the edged thin glass sheet as it relates to handling. Accordingly, there is a need for a new edging process that overcomes the aforementioned problems and other problems associated with edging thin glass sheets. This need and other needs are satisfied by the present invention. 
     SUMMARY 
     A glass edge finishing system, a belt assembly and a method for finishing an edge of a glass sheet have been described in the independent claims of the present application. Advantageous embodiments of the glass edge finishing system, the belt assembly and the method for finishing an edge of a glass sheet have been described in the dependent claims. 
     In one aspect, the present invention provides a glass edge finishing system for finishing an edge of a glass sheet. The glass edge finishing system comprises: (a) a base; and (b) one or more belt assemblies located on the base, where each belt assembly includes: (i) a support frame; (ii) a motor; (iii) a pair of pulleys rotatably mounted on the support frame and driven by the motor; (iv) a belt engaged to and driven by the pair of pulleys, where the belt contacts and finishes the edge of the glass sheet; (v) a belt cleaning device that removes glass debris from the belt as the belt moves past the belt cleaning device; and (vi) a cleaning containment enclosure within which there is located the belt cleaning device, where the cleaning containment enclosure contains the glass debris removed from the belt by the belt cleaning device. 
     In another aspect, the present invention provides a belt assembly for finishing an edge of a glass sheet. The belt assembly comprises: (i) a support frame; (ii) a motor; (iii) a pair of pulleys rotatably mounted on the support frame and driven by the motor; (iv) a belt engaged to and driven by the pair of pulleys, where the belt contacts and finishes the edge of the glass sheet; (v) a belt cleaning device that removes glass debris from the belt as the belt moves past the belt cleaning device; and (vi) a cleaning containment enclosure within which there is located the belt cleaning device, where the cleaning containment enclosure contains the glass debris removed from the belt by the belt cleaning device. 
     In yet another aspect, the present invention provides a method for finishing an edge of a glass sheet. The method comprises the steps of: (a) moving the glass sheet past one or more belt assemblies, where each belt assembly includes: (i) a support frame; (ii) a motor; (iii) a pair of pulleys rotatably mounted on the support frame and driven by the motor; (iv) a belt engaged to and driven by the pair of pulleys; (v) a belt cleaning device; and (vi) a cleaning containment enclosure within which there is located the belt cleaning device; and (b) operating the one or more belt assemblies, wherein each belt assembly rotates the belt such that the belt contacts and finishes the edge of the glass sheet, the belt cleaning device removes glass debris from the belt as the belt rotates past the belt cleaning device, and the cleaning containment enclosure contains the glass debris removed from the belt by the belt cleaning device. 
     Additional aspects of the invention will be set forth, in part, in the detailed description, figures and any claims which follow, and in part will be derived from the detailed description, or can be learned by practice of the invention. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as disclosed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A more complete understanding of the present invention may be had by reference to the following detailed description when taken in conjunction with the accompanying drawings wherein: 
         FIG. 1A  is diagram illustrating a perspective view of an exemplary glass edge finishing system configured to finish two edges of a glass sheet in accordance with an embodiment of the present invention; 
         FIG. 1B  is a diagram illustrating a top view of the exemplary glass edge finishing system configured to finish two edges of the glass sheet in accordance with an embodiment of the present invention; 
         FIG. 1C  is a diagram illustrating a front view of the exemplary glass edge finishing system configured to finish two edges of the glass sheet in accordance with an embodiment of the present invention; 
         FIGS. 2A-2B  are two diagram respectively illustrating a partial side view and a partial perspective view of an exemplary glass sheet that was edged by the glass edge finishing system shown in  FIGS. 1A-1C  in accordance with an embodiment of the present invention; 
         FIG. 3A  is a diagram illustrating a perspective view of an exemplary belt assembly which is used in the glass edge finishing system shown in  FIGS. 1A-1C  in accordance with an embodiment of the present invention; 
         FIG. 3B  is a diagram illustrating a side view of the exemplary belt assembly which is used in the glass edge finishing system shown in  FIGS. 1A-1C  in accordance with an embodiment of the present invention; 
         FIG. 3C  is a diagram illustrating a perspective view of the exemplary belt assembly which has a composite belt with multiple meshes that could be used in the glass edge finishing system shown in  FIGS. 1A-1C  in accordance with an embodiment of the present invention; 
         FIG. 3D  is a diagram illustrating a perspective view of the exemplary belt assembly which has multiple belts that could be used in the glass edge finishing system shown in  FIGS. 1A-1C  in accordance with an embodiment of the present invention; 
         FIG. 4  is a diagram illustrating how a belt (or belts) of the exemplary belt assembly shown in  FIGS. 3A-3D  can be tilted with respect to the glass sheet while finishing an edge of the glass sheet in accordance with an embodiment of the present invention; 
         FIG. 5  is a graph illustrating the edge strength requirements that can be meet when using the traditional grinding wheel and the edge strength requirements that can be meet when using the belt assembly shown in  FIGS. 3A-3B  in accordance with an embodiment of the present invention; 
         FIG. 6A  (PRIOR ART) is a diagram illustrating how a traditional cup grinding wheel creates glass particles A, B, C, and D when finishing the edge of the glass sheet; 
         FIG. 6B  (PRIOR ART) is a diagram illustrating how a traditional formed grinding wheel creates glass particles A, B, C, and D when finishing the edge of the glass sheet; and 
         FIG. 6C  is a diagram illustrating how the belt assembly shown in  FIGS. 3A-3B  creates glass particles A, B, C, and D when finishing the edge of the glass sheet in accordance with an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIGS. 1A-1C , there are several diagrams illustrating different views of an exemplary glass edge finishing system  100  configured to finish two edges  102   a  and  102   b  of a glass sheet  104  in accordance with an embodiment of the present invention. The exemplary glass edge finishing system  100  includes a base  106 , one or more belt assemblies  108  (four shown), a vacuum table  110 , a motion system  112 , a coolant delivery system  114 , and a controller  116 . As shown, the base  106  supports the belt assemblies  108 , the vacuum table  110 , the motion system  112  and the coolant delivery system  114 . The vacuum table  110  has holes therein through which air is drawn to support and secure the glass sheet  104 . The motion system  112  is attached to and moves the vacuum table  110  and the secured glass sheet  104  in a linear motion past the belt assemblies  108  so the secured glass sheet  104  has one edge  102   a  finished by two belt assemblies  108  and another edge  102   b  finished by the other two belt assemblies  108 . The coolant delivery system  114  which has multiple delivery components  118  (four shown) through which a coolant (e.g., gas, liquid) is delivered to each cutting zone (belt and glass interface) to cool the glass sheet  104  and abrasive belt  308  as well as remove the grinding particles and debris from of the glass sheet  104 . The controller  116  includes a processor  120  and a non-transitory computer-readable storage medium  122  which has an executable program stored thereon, where the executable program instructs the processor  120  to control the operations of the belt assemblies  108 , the vacuum table  110 , the motion system  112 , and the coolant delivery system  114  to finish the two edges  102   a  and  102   b  of the glass sheet  104 . The glass edge finishing system  100  may include many other components which are well known in the art but for clarity only the components  106 ,  108 ,  110 ,  112 ,  114 ,  116 , and  118  needed to describe and enable the present invention are discussed herein. 
     Referring to  FIGS. 2A-2B , there are two diagrams respectively illustrating a partial side view and a partial perspective view of one edge  102   a  (for example) of the glass sheet  104  that has been shaped by the glass edge finishing system  100  in accordance with an embodiment of the present invention. In this example, one of the belt assemblies  108  would shape one side  202  of the edge  102   a  and another one of the belt assemblies  108  would shape another side  204  of the edge  102   a . Thus, the edge  102   a  would have two shaped sides  202  and  204  with a relatively flat portion  206  there between. In addition, the edge  102   a  would have two rounded portions  208  and  210  between the relatively flat portion  206  and the two sides  202  and  204 . Furthermore, the edge  102   a  would have two rounded portions  212  and  214  between the sides  202  and  204  and the major surfaces  216  and  218  of the glass sheet  104 . The rounded portions  208 ,  210 ,  212 , and  214  would be created due to a roll-off effect of the belts  308 . Alternatively, the belt assemblies  108  can finish the edges  102   a  and  102   b  of the glass sheet  104  so they have any desired shape and one would not be limited to the particular shape of the illustrated glass sheet  104 . A detailed discussion about the various components that make-up the belt assemblies  108  that shape the edges  102   a  and  102   b  of the glass sheet  104  is provided next with respect to  FIGS. 3A-3D . 
     Referring to  FIGS. 3A-3D , there are several diagrams illustrating different embodiments of the exemplary belt assembly  108  that can be used in the exemplary glass edge finishing system  100  in accordance with the present invention. As shown in  FIGS. 3A-3B , the exemplary belt assembly  108  includes a support frame  302 , a motor  304  (see  FIGS. 1A-1C ), a pair of pulleys  306   a  and  306   b , a belt  308 , a belt cleaning device  310 , a cleaning containment enclosure  312 , one or more tension rollers  314   a  and  314   b  (two shown), a pusher  316 , and a formed backer  318 . The support frame  302  includes a base  320  with a bracket  322  extending upward which on one side there is supported the motor  304  and on the other side there is supported the pair of pulleys  306   a  and  306   b , the abrasive belt  308 , the belt cleaning device  310 , the cleaning containment enclosure  312 , the tension roller(s)  314   a  and  314   b , the pusher  316 , and the formed backer  318 . The belt assembly  108  may include many other components which are well known in the art but for clarity only the components  302 ,  304 ,  306   a ,  306   b ,  308 ,  310 ,  312 ,  314   a ,  314   b ,  316  and  318  needed to describe and enable the present invention are discussed herein. 
     In this example, the pulleys  306   a  and  306   b  which are separated from one another by a desired distance are rotatably mounted on one side of the bracket  322  and driven at a desired speed and torque by the motor  304 . The motor  304  and an optional gear box (not shown) is mounted on the other side of the bracket  322  and directly attached to one of the pulleys  306   a  and  306   b . The abrasive belt  308  is wrapped around the pulleys  306   a  and  306   b  so as to be engaged to and rotatably driven by the pulleys  306   a  and  306   b . In particular, the abrasive belt  308  is positioned such that an outer portion  324  thereof contacts and finishes the edge  102   a  of the glass sheet  104  (see  FIGS. 1A-1D  and  3 B). The abrasive belt  308  could have diamond particles thereon to shape the glass sheet  104  but other minerals have demonstrated equal success in removal of glass such as silicon carbide or aluminum oxide. For example, the abrasive belt  308  could have a 800 mesh grit. To properly position the abrasive belt  308 , two tension rollers  314   a  and  314   b  and the combined pusher  316  and formed backer  318  are used such that the outer portion  324  of the rotating belt  308  is properly positioned to contact, shape and finish the edge  102   a  of the glass sheet  104 . 
     The two tension rollers  314   a  and  314   b  are positioned between the two pulleys  306   a  and  306   b  so as to contact and press against an inner side  326  of the abrasive belt  308  to apply a predetermined tension to the abrasive belt  308 . For instance, each tension rollers  314   a  and  314   b  would have a roller  328  rotatably mounted to a support arm  330  which is secured in a desired position to one side of the bracket  322  such that the roller  328  contacts and presses with a predetermined force against the inner side  326  of the abrasive belt  308 . The combined pusher  316  and formed backer  318  are located between the two tension rollers  314   a  and  314   b . The pusher  316  (e.g., pneumatic pusher  316 , motorized pusher  316 ) is moved so the formed backer  318  is pushed with a desired force against the inner side  326  of the belt  308  so the outer portion  324  thereof is in a proper position to contact, shape, and finish the edge  102   a  of the glass sheet  104 . Basically, the formed backer  318  when positioned behind the abrasive belt  308  helps perform the blending or shaping of the edge  102   a  of the glass sheet  104 . Plus, the formed backer  318  can perform better when mounted to the pneumatic or motorized pusher  316  which pushes the formed backer  310  into the abrasive belt  308  with a fixed force to enable the required glass removal to shape the edge  102   a  of the glass sheet  104 . The formed backer  318  can be made of a smooth low friction material such as Teflon and can have any desired shape such as a flat end, a round end, or a shaped end depending on how one wants to finish the edge  102   a  of the glass sheet  104 . In an alternative, a back-up roller (not shown) can be used instead of the formed backer  318 . The back-up roller would have an appropriate diameter to avoid any sort of contact between the belt  308  and the pusher  316  which would be detrimental to the belt life and process consistency. 
     As shown, the belt assembly  108  also includes the belt cleaning device  310  which is located within the cleaning containment enclosure  312 . The belt cleaning device  310  functions to remove grinding glass debris from the belt  308  as it moves (or rotates) past the belt cleaning device  310 . For example, the belt cleaning device  310  can include one or more brushes (e.g., rotating brushes, stationary brushes), or spray nozzles (e.g., high pressure cleaning jet). The cleaning containment enclosure  312  functions to contain the grinding glass debris that is removed from the belt  308  by the belt cleaning device  310 . The cleaning containment enclosure  312  is desirable since it prevents the grinding glass debris that is removed from the belt  308  by the belt cleaning device  310  from being re-introduced back onto the pristine glass sheet  104 . Another advantage of using the belt cleaning device  310  and the cleaning containment enclosure  312  is that this type of cleaning allows for a more uniform surface of the belt  308  to come into contact with the glass sheet  104  as material removal is taking place. 
     Referring to  FIG. 3C , there is a diagram illustrating a perspective view of the exemplary belt assembly  108  utilizing a composite multiple mesh abrasive belt  308 ′ in accordance with an embodiment of the present invention. In this example, the composite multiple mesh abrasive belt  308 ′ has a coarse matrix mesh  340 ′ (e.g., 320 mesh grit), a recess  342 ′, a medium matrix mesh  344 ′ (e.g., 800 mesh grit), a recess  346 ′, and a fine matrix mesh  348 ′ (e.g., 1200 mesh grit). The composite multiple mesh abrasive belt  308 ′ provides a stepped removal approach to shape the glass sheet  104  where the edge  102   a  of the glass sheet  104  is first shaped by the coarse matrix mesh  340 ′ and then the medium matrix mesh  344 ′ and finally by the fine matrix mesh  348 ′. The recesses  342 ′ and  346 ′ improve the surface contact between the abrasive belt  308 ′ and the edge  102   a  of the glass sheet  104 . In addition, the composite multiple mesh abrasive belt  308 ′ has advantages for belt usage, surface roughness and edge quality. Plus, the belt  308 ′ can minimize edge deflection due to the normal force exerted on the glass sheet  104  by the formed backer  318 . This can be important since the thin glass sheet  104  often has a low stiffness. If desired, the composite multiple mesh abrasive belt  308 ′ can have any number of meshes with different grits and recess sizes to enable the stepped removal approach to shape the glass sheet  104 . 
     Referring to  FIG. 3D , there is a diagram illustrating a perspective view of the exemplary belt assembly  108  utilizing multiple belts  308   a ,  308   b  and  308   c  in accordance with an embodiment of the present invention. In this example, the belt assembly  108  uses the same driving mechanism namely the motor  304  and pulleys  306   a  and  306   b  to rotate the different belts  308   a ,  308   b  and  308   c  which are separated from one another. For instance, the belts  308   a ,  308   b  and  308   c  can respectively have a coarse matrix mesh (e.g., 320 mesh grit), a medium matrix mesh (e.g., 800 mesh grit), and a fine matrix mesh (e.g., 1200 mesh grit). The multiple belts  308   a ,  308   b  and  308   c  provide a stepped removal approach to shape the glass sheet  104  where the edge  102   a  of the glass sheet  104  is first shaped by the coarse grit belt  308   a  and then the medium grit belt  308   b  and finally by the fine grit belt  308   c . The spaces between the belts  308   a ,  308   b  and  308   c  improve the surface contact between the abrasive belts  308   a ,  308   b  and  308   c  and the edge  102   a  of the glass sheet  104 . In addition, the multiple belts  308   a ,  308   b  and  308   c  has advantages for belt usage, surface roughness and edge quality. Plus, the multiple belts  308   a ,  308   b  and  308   c  can minimize edge deflection due to the normal force exerted on the glass sheet  104  by the formed backer  318 . This can be important since the thin glass sheet  104  often has a low stiffness. If desired, the belt assembly  108  can have any number of belts  308  with different grit sizes to enable the stepped removal approach to shape the glass sheet  104 . 
     Referring to  FIG. 4 , there is a diagram illustrating how the belt  308  (or composite belt  308 ′, multiple belts  308   a ,  308   b , and  308   c ) of belt assembly  108  shown in  FIGS. 3A-3D  can be tilted with respect to the glass sheet  104  while finishing an edge  102   a  of the glass sheet  104 . If desired, the belt assembly  108  may be tilted such that the tilted belt  308  (for example) has a belt surface component V h  which matches the traveling speed V g  of the glass sheet  104 . This tilting would be done to achieve a perpendicular grinding of the edge  102   a  of the glass sheet  104 . To achieve the condition where the horizontal component of the belt velocity V h  is equal to the glass velocity V g , the belt assembly  108  can be tilted by tilt angle θ. The vertical component of the belt velocity (V b ) V b  is represented as V v . The range of the tilt angle θ (e.g., +/−5 degrees) with respect to the horizontal is determined by the speed of the belt  308  and the speed of glass sheet  104  to achieve optimum edge quality and strength. In particular, the tilt angle θ can be changed to achieve a certain orientation of the dominant grind pattern (flaw pattern) on the edge  102   a  of the glass sheet  104  and also to accommodate a change in the speed of the glass sheet  104 . Alternatively, one could also change the tilt angle θ based on different glass travelling or belt speeds to maintain a certain ratio to minimize the impact of changes in the belt speed or glass speed on the quality of the grinding of the edge  102   a  of the glass sheet  104 . In yet another alternative, one could also change the tilt angle θ to create a cut pattern which is not perpendicular to the edge  102   a  of the glass sheet  104 . 
     From the foregoing, one skilled in the art should appreciate that the present invention not only includes the glass edge finishing system  100 , the belt assembly  108  but also a method for finishing one or more edges  102   a  and  102   b  of the glass sheet  104 . For instance, the method for finishing an edge  102   a  of the glass sheet  104  can comprise the steps of: (a) moving the glass sheet  104  past one or more belt assemblies  108 , where each belt assembly  108  includes: (i) a support frame  302 ; (ii) a motor  304 ; (iii) a pair of pulleys  306   a  and  306   b  rotatably mounted on the support frame  302  and driven by the motor  304 ; (iv) a belt  308  engaged to and driven by the pair of pulleys  306   a  and  306   b ; (v) a belt cleaning device  310 ; and (vi) a cleaning containment enclosure  312  within which there is located the belt cleaning device  310 ; and (b) operating the one or more belt assemblies  108 , wherein each belt assembly  108  rotates the belt  308  such that the belt  308  contacts and finishes the edge  102   a  of the glass sheet  104 , the belt cleaning device  310  removes glass debris from the belt  308  as the belt  308  rotates past the belt cleaning device  310 , and the cleaning containment enclosure  312  contains the glass debris removed from the belt  308  by the belt cleaning device  310 . 
     The glass edge finishing system  100 , the belt assembly  108  and the method can improve the quality and throughput of the edged glass sheets  104  and particularly the edge shaping of thin glass sheets  104  with a thickness of 3 mm or less. In particular, as stated above the traditional grinding wheel process has several problems, specifically when it comes to edge strength or in another term the durability of the edged glass sheet as it relates to handling. One such handling metric is the bending strength or resistance to breakage during flexure of the edged glass sheet. In this regard,  FIG. 5  shows graph  500  which illustrates the edge strength requirements  502  that can be meet when using the traditional grinding wheel and the edge strength requirements  504  that can be meet when using the new belt assembly  108 . The graph  500  has an x-axis which represents failure stress (MPa) and the y-axis represents probability of failure (%). 
     Furthermore, the new glass edge finishing system  100  enables a clean and strong edge finishing process that produces superior surface and edge attributes at a low cost when compared to the traditional grinding wheel process. One way to describe this particular advantage is to explain how glass particles are created when using two different traditional grinding wheel processes and the new glass edge finishing system  100  to edge glass sheets  104 . The two different traditional grinding wheel processes and the new glass belt assembly  108  are all discussed in more detail below with respect to  FIGS. 6A-6C . 
     Referring to  FIG. 6A  (PRIOR ART), there is a diagram illustrating how the traditional cup grinding wheel  602  creates glass particles A, B, C, and D when finishing the edge  102   a  of the glass sheet  104 . The arrows indicate the glass sheet motion, the wheel rotation and the directions of glass particles C and D. The glass particles are as follows: (1) glass particles A which are generated at the grinding zone; (2) glass particles B which are introduced to the surface of the glass sheet  104  through the cooling liquid; (3) glass particles C which are flying particles that land on the glass sheet  104 ; and (4) glass particles D which are the particles flying off the grinding wheel  602 . As can be seen, the glass particles A, B, C and D do not have a distinct direction for easy containment which means the edged glass sheet  104  needs to undergo a costly washing process. 
     Referring to  FIG. 6B  (PRIOR ART), there is a diagram illustrating how the traditional formed grinding wheel  604  creates glass particles A, B, C, and D when finishing the edge  102   a  of the glass sheet  104 . The arrows indicate the glass sheet motion, the wheel rotation and the directions of glass particles A, B, C and D. The glass particles are as follows: (1) glass particles A which are generated at the grinding zone; (2) glass particles B which are introduced to the surface of the glass sheet  104  through the cooling liquid; (3) glass particles C which are flying particles that land on the glass sheet  104 ; and (4) glass particles D which are the particles flying off the grinding wheel  602 . As can be seen, the glass particles A, B, C and D do not have a distinct direction for easy containment which means the edged glass sheet  104  needs to undergo a costly washing process. 
     Referring to  FIG. 6C , there is a diagram illustrating how the new belt assembly  108  creates glass particles A, B, C, and D when finishing the edge  102   a  of the glass sheet  104  (note: the detailed description of belt assembly  108  is provided above with respect to  FIGS. 3A-3B ). The arrows indicate the glass sheet motion, the wheel rotation and the directions of glass particles A, B and C. The glass particles are as follows: (1) glass particles A which are generated at the grinding zone; (2) glass particles B which are introduced to the surface of the glass sheet  104  through the cooling liquid; (3) glass particles C which are flying particles that land on the glass sheet  104 ; and (4) glass particles D which are the particles removed from the belt  108  by the belt cleaning device  310  and contained within the cleaning containment enclosure  312 . As can be seen, the glass particles D are not located on the glass sheet  104  which makes it easier to wash the edged glass sheet  104 . 
     A discussion is provided next to explain in detail how the new glass edge finishing system  100  incorporating the belt assembly  108  addresses each of the ten problems associated with the traditional grinding wheel process discussed above in the “Background” section.
         Solution to problem nos. 1 &amp; 2: formed grinding wheels are difficult to make when a small tight radius is required. Since formed grinding wheels are made using an Electrical Discharge Machining (EDM) process, the tool used to create this form in the grinding wheel can wear quickly and as a result a blunt shape at the bottom of the resultant groove can be formed. This is not desirable for the final shape of the edged glass sheet glass. These problems are resolved by using the belt(s)  308  to create the required form. Plus, the belt(s)  308  can produce the shaped edges  102   a  and  102   b  of the glass sheet  104  for a much longer period of time when compared to using the formed grinding wheel due to the larger surface area of the belt(s)  308  and the fact the formed backer  318  has very little wear as compared to the grinding wheel process.   Solution to problem no. 3: since there is a significant increase in surface area and the ability to use the entire grinding matrix on the abrasive belt(s)  308  it is more cost effective when compared to using the grinding wheel which may use diamonds as the grinding matrix. Thus, the use of belt(s)  308  will not only decrease yearly consumable cost but also production costs since line downtime associated with changing belt(s)  308  is much less when compared changing grinding wheels.   Solution to problem nos. 4, 5, 6 and 7: since the belt(s)  308  are typically flat one side of the glass sheet  104  can be shaped at a time which means the glass particles A and C can be released more freely when compared to the grinding wheel process thus preventing material buildup which can cause undesirable chipping. Since, the belt(s)  308  also have a large surface area that can come into contact with the glass sheet  104  during the grinding process this means that the belts grain size can be reduced which results in a finer, smoother surface on the edged glass sheet  104 .   Solution to problem no. 8: since the belt assembly  108  when compared to the grinding wheel process uses a gentler edge grinding process this causes the grinding debris (e.g. glass particles D) to stay in a small area and mainly cling to the abrasive belt(s)  308  so the belt cleaning device  310  can remove the glass particles D which will result in a much cleaner final edged glass sheet  104 .   Solution to problem no. 9: since the belt grinding process is gentler than grinding with a grinding wheel this means that the surface finish produced on the glass sheet  104  has less defects within which glass debris can become trapped.   Solution to problem no. 10: since the belt grinding process requires less precision when compared to the grinding wheel process which has problematical precision limitations due to the machine systems used to position the grinding wheel this is desirable when it comes to reducing the amount of stock used.       

     Although several embodiments of the present invention have been illustrated in the accompanying Drawings and described in the foregoing Detailed Description, it should be understood that the invention is not limited to the disclosed embodiments, but is capable of numerous rearrangements, modifications and substitutions without departing from the invention as set forth and defined by the following claims. It should also be noted that the reference to the “present invention” or “invention” used herein relates to exemplary embodiments and not necessarily to every embodiment that is encompassed by the appended claims.