WO2013180463A1

WO2013180463A1 - Apparatus for removing cracks from sheared edge of glass plate

Info

Publication number: WO2013180463A1
Application number: PCT/KR2013/004707
Authority: WO
Inventors: 박재훈
Original assignee: 에이그라스 주식회사
Priority date: 2012-05-29
Filing date: 2013-05-29
Publication date: 2013-12-05
Also published as: CN104379518A; KR20130133408A; KR101402097B1; CN104379518B

Abstract

The present invention relates to an apparatus for processing a sheared edge of a thin glass plate, capable of removing fine cracks formed at the sheared edge of the glass plate. The apparatus of the present invention comprises: a burner for melting the sheared edge of the glass plate; a combustion gas supply means for supplying combustion gas to the burner; and a rotary vacuum-suction gripper for suctioning and holding the glass plate and bringing the glass plate close to the burner. The burner includes a flame-emitting surface, and a plurality of flame-emitting holes formed in the flame-emitting surface. The rotary vacuum-suction gripper includes a rotary shaft arranged vertically to the flame-emitting surface of the burner; a hub fixed at the rotary shaft; and a vacuum-suction arm, one end of which is fixed at the hub and the other end of which has a suction surface formed thereon. The vacuum-suction arm is arranged so as to enable one side of the suctioned glass plate to face the flame-emitting surface of the burner in a predetermined position during the rotation of the rotary shaft.

Description

Cutting edge crack remover on glass sheet

TECHNICAL FIELD The present invention relates to an apparatus for cutting edges of thin glass, and more particularly, to an apparatus for removing fine cracks formed at the edges of cutting of a glass plate.

Display devices are used in electronic devices such as smart phones, tablet PCs, monitors, and TVs. Thin glass is used as the substrate of the LCD display device among the display devices. In addition, thin glass is used also as a window panel for protecting the display part of a display apparatus. In addition, thin glass is used also for a touch sensor apparatus. In order to manufacture thin glass used for various electronic devices as described above, a process of cutting a large glass plate is essential.

In general, as a method of cutting a glass plate, a method of forming a scribing line first rather than completely cutting the glass to make a mechanically vulnerable portion and breaking the vulnerable portion by applying a physical or thermal shock to the vulnerable portion is known. Moreover, the waterjet cutting method which cuts by the pressure of water is known. When braking by applying a physical or thermal shock to the glass plate, the glass is hard and susceptible to mechanical impact, so that minute cracks are generated at the cut edges. If the glass is strengthened without removing the fine cracks generated at the cut edges of the glass plate, there is a risk that the fine cracks progress and the glass plate itself is broken as time passes.

In order to prevent breakage of the glass plate due to such fine cracks, the edges are chamfered after not only removing the fine cracks formed at the cutting edges but also cutting the cutting surfaces to remove sharp edges. Use tools such as diamond wheels for grinding or polishing to cut edges or to chamfer edges.

Fine glass particles are generated when grinding and polishing the cut edges of thin glass cut to a predetermined size using a grinding and polishing tool. In order to remove the generated fine glass particles remaining in the thin glass, a separate washing and drying process is required after the chamfering and chamfering process to increase the manufacturing cost. In addition, in order to prevent scratches on the surface of the glass plate, a process of attaching a protective film on both sides or a single side is processed, and a process of removing the protective film after processing may be added. Further, even when the cutting edges are ground or polished, fine cracks deeply advanced may not be removed, or second cracks may be generated in the thin glass due to the impact of the rotating tool during grinding or polishing. In addition, there is a problem that damage the expensive equipment when the generated fine glass particles invade the manufacturing equipment.

The present invention relates to an apparatus for fundamentally solving the problems arising in the conventional process of removing the cracks generated in the cut edge of the thin glass cut into a predetermined size as described above. An object of the present invention is to provide an apparatus capable of completely removing fine cracks formed at the cut edges of a glass plate. In addition, an object of the present invention is to provide a device capable of removing cracks formed on the cutting edge of the glass plate without generating fine glass particles during crack removal. In addition, an object of the present invention is to provide a crack removal device in which secondary cracks do not occur due to mechanical impact during crack removal.

The cutting edge crack removal apparatus of the glass plate which concerns on this invention is a burner for melting the cut edge of a glass plate, the combustion gas supply means for supplying combustion gas to a burner, and a rotary vacuum for adsorbing and holding a glass plate and approaching a burner. Adsorption gripper. The burner includes a flame radiation surface and a plurality of flame radiation holes formed on the flame radiation surface. The rotary vacuum suction gripper includes a rotary shaft disposed to be perpendicular to the flame emitting surface of the burner, a hub fixed to the rotary shaft, and a vacuum suction arm having one end fixed to the hub and an adsorption surface formed at the other end. The vacuum suction arm is provided so that one surface of the glass plate held by the suction plate at the predetermined position during the rotation of the rotating shaft faces the flame emission surface of the burner. In addition, the vacuum suction arm rotates horizontally with respect to the flame emitting surface. More preferably, the rotary vacuum suction gripper includes a plurality of vacuum suction arms for improving productivity. When each vacuum suction arm is positioned in a vacuum suction section with respect to one rotation of the rotating shaft, the suction surface is vacuumed and the vacuum is applied. When located in the release section, the vacuum applied to the suction surface is released. For example, the first position and the second position at which the rotation shaft stops with respect to one rotation of the rotation shaft belong to the vacuum suction section, and the third position and the fourth position belong to the vacuum release section. In this case, each of the vacuum adsorption arms is subjected to a vacuum on the adsorption surface at the first position to adsorb and grip the glass plate, and to cut the edge of the glass plate directly into the flame radiated from the burner at the second position. It is possible to remove the crack of the cutting edge by approaching the flame radiation surface, and to release the gripped glass plate by releasing the vacuum applied to the adsorption surface at a third position.

In addition, the rotary vacuum suction gripper is adapted to maintain a distance between the flame emitting surface and the glass plate such that the cut edge contour of the glass plate vacuum-adsorbed to the vacuum suction arm is in direct contact with the flame radiated from the flame radiating hole of the burner. The flame radiating surface of the burner is disposed in parallel and spaced apart at a predetermined distance to face one surface of the glass plate, and the plurality of flame radiating holes correspond to the cutting edges of the glass plate when the adjacent flame radiating holes are connected by imaginary lines. It is formed on the flame-radiating surface to form a closed curve. When only a part of the cutting edge is heated by using a burner having a flame emitting surface and a plurality of flame emitting holes, the rotary vacuum suction gripper arranges one surface of the glass plate so as to be spaced apart from the flame emitting surface of the burner by a certain distance. The flame radiated from the hole is brought into direct contact with the cut edge of the glass plate so that the cut edge is locally heated.

The direction of contacting the flame with the cut edges in order to heat the cut edges of the glass plate is not limited. For example, the flame may be directed to the cutting edge by directing the flame from the lower portion of the glass plate to the upper portion, or the flame may be directed to the cutting edge by directing the flame toward the lower portion of the glass plate. In addition, the flame may be directed at an inclined plane so that the flame contacts the cut edge.

In addition, the orthogonal projection on the glass plate of the virtual single closed curve connecting the center of each of the plurality of flame-emitting holes is preferably arranged outside the cut surface of the cutting edge of the corresponding glass plate. This is to arrange the center of the flame radiation hole on the outside of the cut surface, so that the center of the flame radiated from the flame radiation hole is radiated out of the glass plate, so that the side of the flame contacts the cutting edge of the glass plate and the cut surface.

In addition, the flame radiation hole can be implemented in various shapes. For example, a slit shape having a width in the range of 0.1-2 mm or a circular hole having a diameter in the range of 0.1-2 mm can be formed as a flame spinning hole. In addition, the spacing between neighboring flame-emitting holes is appropriately adjusted in the range of 3-50 mm in proportion to the diameter of the flame-emitting holes, so that the flames emitted from neighboring flame-emitting holes continuously and seamlessly contact the cutting edges of the glass plate. Be sure to In addition, the spacing between the glass plate and the flame emitting surface is preferably such that the oxidized salt and the reducing salt of the flame are in direct contact with the cut edge and the cut surface of the glass plate.

In addition, by adjusting the size of the flame, and the distance between the glass plate and the flame emitting surface properly, it is possible to remove the cracks formed at the cutting edge of the upper surface and the cutting edge of the lower surface of the glass plate at once. That is, the burner and the glass plate are arranged so that the flames radiated from the flame radiating hole of the burner simultaneously directly contact the cutting edge defining the first surface of the glass plate and the cutting edge defining the second surface located opposite the first surface of the glass plate. do. In addition, the combustion gas for generating a flame uses a combustion gas containing LNG, LPG or acetylene gas and oxygen.

The burner further includes burner position adjusting means for adjusting the position of the burner such that the flame radiated from the flame radiating hole is in contact with the cutting edge of the glass plate adsorbed on the suction surface of the vacuum suction arm. The burner position adjusting means includes a moving unit for moving the burner up and down, and a rotating means for rotating the burner, and may further include a tilt adjusting means for adjusting the inclination of the flame inclined surface of the burner.

According to the present invention, as the rotary vacuum suction gripper rotates with the rotation of the rotary shaft, each vacuum suction arm is vacuumed at the first position to suck and hold the glass plate, and the flame is radiated from the burner at the second position. Improve the productivity by automating the cutting edge crack removal process by removing the crack at the cutting edge by bringing the glass plate close to the flame-radiating surface so that the cutting edge is in direct contact, and releasing the gripped glass plate by releasing the vacuum at the third position. .

The apparatus may further include a glass plate adsorption station for supporting one surface of the glass plate when the surface of the glass plate is adsorbed and gripped by the adsorption surface of the vacuum adsorption arm. The glass plate adsorption station includes a plate which is in contact with the other surface of the glass plate, and one end of which is fixed to the plate, and the other end of which is attached to the main frame. However, the present invention is not limited thereto, and any one can be used as long as the adsorption surface can stably support the other surface of the glass plate when the surface of the glass plate is adsorbed.

In addition, the cutting edge crack removal device of the glass plate according to the present invention, the supply conveyor for continuously supplying the glass plates to the rotary vacuum suction gripper, the discharge conveyor for continuously discharging the glass plates provided from the rotary vacuum suction gripper, supply It is preferred to include preheating means for preheating the glass plates moving on the conveyor and cooling means for cooling the glass plates moving on the discharge conveyor.

The preheating temperature of the glass plate should be in the range of 500 ° C. to 630 ° C., which is a temperature range near the annealing of the glass, and is preferably preheated to a temperature of about 600 ° C. Preheating before the crack is melted and removed by flame is to prevent breakage of the glass plate due to thermal stress due to rapid temperature change. Residual strain is present at the cut edges where the crack is removed by flames. In order to remove it, annealing operation is necessary during slow cooling. The cooling rate is preferably maintained at a rate of 14-18 ° C./min up to 350 ° C. and maintained at a rate of 56 ° C.-62 ° C./min from 350 ° C. to room temperature. The supply conveyor and the preheating means continuously preheat the glass plate and supply it to the rotary vacuum suction gripper, and the discharge conveyor and the cooling means are configured to continuously cool the glass plate from which the cutting edge cracks are removed, thereby increasing productivity.

It also shortens the length of the conveyor, increases the area of the glass plate in contact with the air, reduces preheating and cooling time, and feeds and discharges inclined on the conveyor so that the glass plate can be easily adsorbed by the rotary vacuum suction gripper. It is desirable to. A plurality of holders may be provided on the supply conveyor and the discharge conveyor, each having a guide for tilting and supporting the glass plates so that the glass plates can be tilted and transported. Also, by synchronizing the operation of the rotary vacuum suction gripper with the supply conveyor and the discharge conveyor, the vacuum suction arm positioned at the first position adsorbs and grips the glass plate, and at the same time, the glass plate adsorbed and held on the vacuum suction arm positioned at the second position is cut. The edges can be machined from the burner, the cracks removed, and the cracked glass plates held on the vacuum suction arm located in the third position can be laid down on the discharge conveyor to increase productivity.

On the other hand, when the glass plate placed on the guide of the holder is sucked by the vacuum suction arm of the rotary vacuum suction gripper and immediately rotated while being inserted into the holder, the glass plate is caught by the guide and is broken. Therefore, it is preferable to install the rotary vacuum suction gripper to move up and down a certain distance so that the rotary vacuum suction gripper can be rotated after removing the glass plate from the guide of the holder. In addition, it is preferable to configure the rotary vacuum suction gripper to move a certain distance up and down in order to insert the glass plate from which the cutting edge cracks are removed in the guide of the glass plate holder installed on the discharge conveyor.

In addition, the preheating means is a plurality of preheating heaters installed along the longitudinal direction in the upper part of the supply conveyor, preheating air passages are respectively installed so that one end is connected to the upper portion of the plurality of preheating heaters, and the other end of the preheating air passage is It comprises a first blower for supplying a plurality of preheating heaters. In addition, the cooling means is a plurality of cooling heaters installed along the longitudinal direction in the upper portion of the discharge conveyor, the cooling air passages are respectively installed so that one end is connected to the upper portion of the plurality of cooling heaters, the other end of the cooling air passage is connected to the outside It includes a second blower for supplying a plurality of cooling heaters. In addition, the auxiliary cooling means provided in the adjacent position of the cooling means, a plurality of connecting pipes provided along the longitudinal direction on the upper part of the discharge conveyor, and auxiliary cooling air passages respectively installed so that one end is connected to the plurality of connecting pipes; A third blower is connected to the other end of the cooling air passage to supply external air to the plurality of connection pipes.

According to the present invention, the glass plate conveyed in an inclined state on the conveyor is heated to gradually increase the temperature while transporting the glass plate by mixing hot air and cold air, while transporting the glass plate by mixing hot air and cold air. The temperature can be cooled to lower gradually. That is, hot air and cold air can be properly mixed and supplied to the glass plate so that an appropriate temperature gradient occurs along the longitudinal direction of the conveyor. In particular, in order to shorten the length of the discharge conveyor, the cooling means has a first cooling section in which the temperature falls gently along the longitudinal direction of the discharge conveyor, and the auxiliary cooling means drops rapidly along the length direction of the discharge conveyor. In order to form the second cooling section, the cooling air passage and the auxiliary cooling air passage are preferably installed to increase along the longitudinal direction.

According to the present invention, there is provided an apparatus for removing fine cracks generated by cutting edges using a flame.

According to the present invention, a flame is used to remove fine cracks generated at the cut edges. Therefore, it is possible to completely remove the crack formed on the cutting edge by the local melting of the cutting edge has the effect of producing a high quality cut glass plate. In addition, it is possible to produce a cut glass plate of excellent quality that does not cause secondary cracking due to mechanical impact during crack removal. In addition, the glass plate cutting edge crack removal device is synchronized with the operation of the rotary vacuum suction gripper configured to rotate horizontally and the supply conveyor and the discharge conveyor has an excellent productivity effect. In addition, it is possible to remove the crack of the glass plate cutting edge without generating any fine glass particles at all can reduce the manufacturing cost by eliminating the cleaning and drying process.

1 is a front view showing an embodiment of a cutting edge crack removal device of a glass plate according to the present invention.

2 is a plan view of FIG. 1.

FIG. 3 is an enlarged view of portion A shown in FIG. 1.

4 is a side view schematically showing a state seen from the right side of FIG. 3.

5 is a cross-sectional view taken along the line B-B shown in FIG.

6 is a perspective view of one embodiment of a rotary vacuum suction gripper used in the apparatus shown in FIG.

7 is a cross-sectional view of a portion where the vacuum suction arm and the suction surface of FIG. 6 are installed.

FIG. 8 is a perspective view of one embodiment of a burner used in the apparatus shown in FIG. 5. FIG.

FIG. 9 is a cross-sectional view of a portion where the burner of FIG. 8 is installed. FIG.

10 is a perspective view of one embodiment of the glass plate preheating means used in the apparatus shown in FIG. 1.

FIG. 11 is a perspective view of a glass plate holder for conveying the glass plate shown in FIG. 10.

12 is a perspective view of one embodiment of the glass plate cooling means used in the apparatus shown in FIG. 1.

FIG. 13 is a perspective view of a glass plate in which cracks are generated at cut edges. FIG.

It is explanatory drawing which shows the state which the cutting edge crack of a glass plate is removed in the apparatus of FIG.

Other objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments associated with the accompanying drawings.

Hereinafter, a preferred embodiment of the cut edge crack removal device of the glass plate according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a front view showing an embodiment of a cutting edge crack removal device of a glass plate according to the present invention. The cutting edge crack removal apparatus 100 of this embodiment is provided with the main frame 10. The main frame 10 is connected to the supply conveyor 50 at one end and the discharge conveyor 60 is connected to the other end. At least one heater 11 is mounted inside the body frame 10 to preheat the inside of the body frame 10. The glass plate adsorption station 12 is installed inside the main body frame 10 at a position adjacent to the supply conveyor 50. The glass plate adsorption station 12 supports the lower surface 72, which is the other surface of the glass plate 70, so that the rotary vacuum adsorption gripper 20 can safely adsorb the glass plate 70 transferred through the supply conveyor 50. The glass plate adsorption station 12 includes a plate 12a and a shaft 12b having one end fixed to the plate 12a and the other end fixed to the body frame 10. Flame inspection means 13 is installed on the inner side of the body frame 10 at intervals from the flame radiation surface (35a) of the burner (30). Flame inspection means 13 is to detect whether the flame (f) of the burner 30 is ejected at the correct position to remove the crack (C) of the glass plate 70, it may be used a camera and a flame detector.

2 and 5, the rotary vacuum suction gripper 20 is installed at the inner center of the main frame 10, and sucks and rotates the glass plate 70 supplied through the supply conveyor 50 to burner ( Passes 30 to the discharge conveyor (60). The burner 30 is installed at a position adjacent to the rotary vacuum suction gripper 20 and is used to remove the crack C generated at the cutting edge of the glass plate 70.

FIG. 6 is a perspective view of one embodiment of the rotary vacuum suction gripper used in the apparatus shown in FIG. 5, and FIG. 7 is a cross-sectional view of a portion in which the vacuum suction arm and the suction surface of FIG. 6 are installed. The rotary vacuum suction gripper 20 is installed at the inner center of the main frame 10. The motor 21 is connected to one end of the rotation shaft 22. The hub 23 is fixed to the other end of the rotation shaft 22 and rotates together with the rotation shaft 22. One end of the vacuum suction arm 24 is fixed to the hub 23, and in this embodiment, four vacuum suction arms 24 are fixed at equal intervals (90 ° intervals) along the circumferential direction of the hub 23. At the free end of each of the vacuum suction arms 24, four suction surfaces 24a are formed to suck and hold the glass plate 70 by vacuum. The rotary shaft 22 is disposed to be perpendicular to the flame emitting surface 35b of the burner 30, and the suction surfaces 24a of each of the four vacuum suction arms 24 rotate about the rotary shaft 22. It is arranged to face the flame radiation surface 35b of the burner 30 at a predetermined position.

Referring to Figure 6, the rotary vacuum suction gripper 20 is provided with a first moving means 25 to be movable in the vertical direction by a hydraulic or pneumatic cylinder. The first moving means 25 includes a first fixing bracket 25a, a first moving guide rail 25b, a first driving part 25c and a first moving bracket 25d. The first fixing bracket 25a is fixed inside the body frame 10. The first moving guide rail 25b is fixed to the first fixing bracket 25a so that one side thereof is parallel to the rotation shaft 22 and the first driving part 25c is mounted on the other side thereof. The first moving bracket 25d moves up and down along the first moving guide rail 25b and is fixed to the side of the bracket supporting the motor 21. That is, the rotary vacuum suction gripper 20 is rotated horizontally so that the hub 23 is parallel to the flame radiation surface 35b together with the rotating shaft 22 by the operation of the motor 21, the first moving means 25 The hub 23 moves vertically together with the rotation shaft 22 by the operation of.

In addition, a plurality of vacuum passage inlets (not shown) corresponding to the vacuum suction arm 24 are formed at the end of the rotary shaft 22, and extend into the rotary shaft 22 to each vacuum suction arm 24. Four vacuum connection passages 22a formed to communicate with the suction surface 24a of the are connected. The hub 23 is formed with four first vacuum passages 23a at 90 ° intervals at positions communicating with the respective vacuum connection passages 22a. Second vacuum passages 24b are formed in the vacuum suction arms 24 so as to communicate with the four first vacuum passages 23a. When the rotary shaft 22 rotates and stops, the position where the vacuum suction arm 24 sucks and grips the glass plate 70 supplied from the supply conveyor 50 is called a first position, and the vacuum suction arm 24 is The position where the suction-holding glass plate 70 faces the flame-emitting surface 35b of the burner 30 to remove cracks at the cutting edges is called a second position. In addition, a position for releasing the vacuum from the vacuum suction arm 24 to the discharge conveyor 60 by discharging the glass plate 70 from which the crack C is removed is referred to as a third position, and between the first position and the third position. In this case, the position where the glass plate 70 is not adsorbed on the vacuum suction arm 24 is called a fourth position.

In this embodiment, the hub 23 fixed to the rotating shaft 22 repeatedly rotates and stops at intervals of 90 degrees. At this time, the suction surface of the vacuum suction arm 24 positioned at the first position for suction-holding the glass plate 70 supplied through the supply conveyor 50 is vacuumed in the first and

second vacuum passages

23a and 24a. This is a jammed state. In addition, when the vacuum suction arm 24 which sucks and grasps the glass plate 70 at the first position is rotated 90 ° in the counterclockwise direction, the second position where the burner 30 for processing the crack of the cutting edge of the glass plate 70 is located. Will be located. The glass plate 70 attached to the adsorption surface of the vacuum adsorption arm 24 at the second position is disposed above the flame radiation surface 35b, and the vacuum state is maintained so that the glass plate 70 does not fall off the adsorption surface. When the vacuum suction arm 24 holding the glass plate 70 in the second position rotates 90 ° in the counterclockwise direction, the vacuum suction arm 24 is positioned at the third position for transferring the glass plate 70 to the discharge conveyor 60. While the vacuum applied to the first and

second vacuum passages

23a and 24a of the vacuum suction arm 24 is released in the third position, the vacuum applied to the suction surface 24a of the vacuum suction arm 24 is released to suck the grip. The glass plate 30 is separated from the adsorption surface 24a. At this time, the fallen glass plate 70 is mounted on the holder 64c of the discharge conveyor 60. After the vacuum is released and the vacuum adsorption arm 24 which delivers the glass plate 70 to the discharge conveyor 60 is rotated 90 ° counterclockwise and positioned at the fourth position, the glass plate 70 is supplied through the supply conveyor 50. ) Is rotated to the first position for suction gripping. In the case of continuously processing a plurality of glass plates, this process is repeated while the rotating shaft 22 rotates and stops in synchronization with the

conveyors

50 and 60.

FIG. 8 is a perspective view of one embodiment of a burner used in the apparatus shown in FIG. 5, and FIG. 9 is a cross-sectional view of a portion in which the burner of FIG. 8 is installed. Referring to FIG. 8, the burner 30 includes a burner fixing bracket 31, a burner position adjusting means, a burner housing 34, a burner support part 35, and a combustion gas supply pipe 37. Burner fixing bracket 31 is fixed to the inside of the main frame 10. The burner position adjusting means includes a rotating means 32 and a shandong means 33. The rotating means 32 is installed on the burner fixing bracket 31 and moves the burner support part 35 supporting the flame radiating plate 35a in the horizontal direction so that the flame radiating surface (according to the position of the glass plate 70) 35b) to facilitate adjustment. The rotating means 32 has a first motor 32a and a second motor 32c which are respectively installed on both sides of a fixing bracket (not shown) installed on the burner fixing bracket 31. The first motor 32a and the second motor 32c are stretched in the other end direction from one end of the burner fixing bracket 31. The third motor 32b is mounted to expand and contract toward the second motor 32c from the first motor 32a. The rotating plate 32d is installed at the inner center of the first to

third motors

32a, 32b, and 32c, and the rotating plate 32d is rotated according to the expansion and contraction operation of each motor.

In addition, the Shanghai moving means 33 includes a second fixing bracket 33a, a second moving guide rail 33b, a second driving part 33c and a second moving bracket 33d. The second fixing bracket 33a is fixed inside the body frame 10. One end of the second moving guide rail 33b is fixed to the second fixing bracket 33a and installed in parallel with the burner housing 34, and the second driving part 33c is mounted at the other end thereof. The second moving bracket 33d moves up and down along the second moving guide rail 33b and is fixed to the side of the burner fixing bracket 31. That is, the burner 30 moves the flame radiation surface 35b vertically by the operation of the second driving part 33c. Burner position adjusting means may further include a tilt adjusting means for adjusting the inclination of the flame inclined surface (35b) of the burner (30).

Referring to FIG. 9, one end of the burner housing 34 is fixed to the center of the upper end of the rotating plate 32d, and the other end thereof is connected to the burner support 35. The burner support part 35 receives the flame radiating plate 35a at the top. The flame radiating plate 35a has a flame radiating surface 35b. In the present embodiment, since the glass plate 70 is planar, the flame emitting surface 35b is also planar but is not limited thereto. If the cut glass plate 70 is in a curved shape, the flame-emitting surface 35b is also formed in a corresponding curved shape. The flame radiating plate 35b is processed with a flame radiating hole 35c according to the cutting edge contour of the glass plate 70 to be processed. If the shape of the glass plate 70 to be processed is changed, the flame radiating plate 35b corresponds to the changed shape. The hole 35c can be replaced with one formed. The flame-emitting surface 35b is formed with a plurality of flame-emitting holes 35c having a constant diameter at regular intervals. The diameter of the flame spinning hole 35c is preferably in the range of 0.1-2 mm. The diameter of the flame radiation hole 35c is determined in consideration of the distance between neighboring flame radiation holes 35c. In addition, the diameter of the flame radiation hole 35c is determined in consideration of the gap between the flame radiation surface 35b and the glass plate 70 and the thickness of the glass plate 70. In this embodiment, the diameter of the flame spinning hole 35c is 0.6 mm, the spacing between the flame spinning holes 35c is 0.8-1.2 mm, and the thickness of the glass plate 70 is 0.7 mm. In addition, in order to remove the crack C of a cutting edge with flame f, the space | interval between the flame-emitting surface 35b and the glass plate 70 was 11 mm. The flame radiation hole 35c is in communication with the combustion gas supply pipe 37. In addition, in the present embodiment, the flame radiation hole 35c is not limited to a circular shape, but may also have a slit shape having a predetermined width and length.

The virtual single closed curve connecting the centers of the adjacent flame emitting holes 35c has the same shape as the contour of the corresponding cut edge of the glass plate 70, and the flame emitting holes 35c have the glass plate 70 of the corresponding single closed curve. Orthogonal projection for is formed to be located on the outside of the glass plate (70). The contour of the lower outer cut edge 72a of the lower surface 72 of the glass plate 70 corresponds to an imaginary single closed curve, and the contour of the lower outer cut edge 72a inside the orthogonal projection of the single closed curve for the glass plate 70. Flame spinning hole 35c is formed to include this.

It is provided inside the main body frame 10 so that the flame-emitting surface 35b may face upward. The rotary shaft 22 of the rotary vacuum suction gripper 20 rotates 90 degrees horizontally by the glass plate 70 adsorbed on the suction surface 24a of the vacuum suction arm 24 so that the cutting edge contour is flame spinning of the burner 30. The gap between the flame-emitting surface 35b and the glass plate 70 is maintained so as to directly contact the flame f radiated from the hole 35c. The burner 30 is disposed below the glass plate 70, and the glass near the cut edge melted by the flame f of the burner 30 rides on the cut surface 73 of the glass plate 70 by gravity. Will flow down.

A coolant passage (not shown) is formed in the burner support part 35 to cool the burner 30 from overheating. In addition, a combustion gas mixer (not shown) is connected to the connector of the burner 30. The flue gas mixer is mixed with LNG, LPG or acetylene gas and oxygen from an external gas source. Combustion gas supply means 37 for supplying combustion gas to the burner 30 is connected to the gas pipe.

1 to 2 and 10, the supply conveyor 50 is installed in the frame 40, and continuously supplies the glass plate 70 to the rotary vacuum suction gripper 20. A drive sprocket 54a for driving the supply conveyor 50 is disposed on the rotary vacuum suction gripper 20 side, and a driven sprocket 54b is disposed on the opposite side. Although not shown in the drawing, the drive sprocket 54a is connected with a drive motor for the supply conveyor 60.

10 and 11, the feed conveyor 50 has a pair of chains 54 installed in the frame and a plurality of glass plate holders fixed to the pair of chains 54 and installed to move together with the chains 54. (54c). The glass plate holder 54c is fixed so as to extend from both sides of the guide fixing bracket 54c-1 having both ends fixed to the pair of chains 54 and the guide fixing bracket 54c-1, and the glass plate 70 is lifted up. And a pair of guides 54c-2 and 54c-3 configured to respectively support the side surfaces of the glass plate 70 in the extended state. The pair of guides 54c-2 and 54c-3 are installed in an inclined state with respect to the guide fixing bracket 54c-1. A plurality of glass plate holders 54c are provided adjacent to each other at regular intervals along the loop-shaped chain 54. The glass plate holder 54c is installed so that the glass plate 70 can be transferred in an inclined state, so that a larger amount of the glass plate can be preheated, and the glass plate 70 in contact with air is widened to uniformly glass plate. Allow to preheat. 11, the pair of guides 54c-2 and 54c-3 are inclined so that the edges of the glass plate 70 are in line contact with the pair of guides 54c-2 and 54c-3. It is desirable to support the glass plate. This is because the glass plate 70 can be prevented from being damaged by minimizing the area of the glass plate in contact with the glass plate holder 54 when transferring the glass plate 70. In addition, in the present Example, the glass plate holder 54 supports only the side surface of the glass plate 70 by the pair of guides 54c-2 and 54c-3, and is conveyed. Therefore, the glass plate 70 can be easily attached to the glass plate adsorption station 12 as shown in FIG. 3 and FIG. Therefore, the glass plate 70 placed on the glass plate adsorption station 12 can be easily adsorbed and gripped by the rotary vacuum adsorption gripper 20.

1 to 2 and 12, the discharge conveyor 60 is installed in the frame 40, and after the cutting edge crack C is removed from the burner 30, the rotary vacuum suction gripper 20 is removed. The glass plate 70 provided is received and continuously discharged. In addition, a drive sprocket 64a for driving the discharge conveyor 60 is disposed on the rotary vacuum suction gripper 20 side, and a driven sprocket 64b is disposed on the opposite side. Although not shown in the drive sprocket 64a, a drive motor for the discharge conveyor 60 is connected. In the present embodiment, the glass plate 70 supply conveyor 50 and the discharge conveyor 60 use a chain conveyor, but are not limited thereto. The glass plate holder 64c provided in the discharge conveyor 60 is provided in the same structure as the glass plate holder 54c provided in the supply conveyor 50. As shown in FIG.

By synchronizing the operations of the rotary vacuum suction gripper 20 and the supply conveyor 50 and the discharge conveyor 60 according to the present invention, the plurality of vacuum suction arms 24 rotate to suck the glass plate 70 in the first position. And the cutting edge of the glass plate 70 is processed by the burner at the second position, and the glass plate 70 from which the cutting edge crack C is removed at the third position is lowered on the discharge conveyor 60. To increase productivity. Although only the glass plate holder 54c of the feed conveyor 50 is shown in FIG. 11, the discharge conveyor 60, which is not shown in detail, also has a pair of chains 64, the same structure for each chain 64. Glass plate holder 64c is provided.

In addition, the cutting edge crack removal apparatus 100 of this embodiment is provided with the preheating means 50a for preheating the glass plate 70 which moves on the supply conveyor 50. As shown in FIG. That is, before supplying the glass plate 70 to the rotary vacuum adsorption gripper 20 using the supply conveyor 50 to melt and remove the cracks by flame f, the glass plate 70 due to the thermal stress caused by a sudden temperature change is obtained. It is necessary to preheat the glass plate 70 to prevent breakage. The preheating temperature of the glass plate 70 can be in the 500-630 degreeC range which is the temperature range of the annealing vicinity of glass, and it is preferable to preheat in about 600 degreeC range. The glass plate preheating means 50a of this embodiment has a plurality of preheating

heaters

51a, 51b, 51c provided in the longitudinal direction on the upper part of the supply conveyor 50, and once on the plurality of preheating

heaters

51a, 51b, 51c. It includes a preheating air passage 52 is installed so as to connect each. The other end of the preheating air passage 52 is provided with a first blower 53 for supplying outside air to the plurality of preheating

heaters

51a, 51b, 51c in order to preheat the glass plate 70. Therefore, the temperature of the air discharged along the longitudinal direction of the supply conveyor 50 is adjusted by adjusting the temperatures of the plurality of preheating

heaters

51a, 51b, 51c or by adjusting the amount of air supplied from the first blower 53. I can regulate it. That is, hot air and cold air can be appropriately mixed and supplied to the glass plate 70 so that an appropriate temperature gradient is generated along the longitudinal direction of the supply conveyor 50. (shown in p section of the graph along the longitudinal direction of FIG. 2). The temperature of the glass plate 70 transferred by the supply conveyor 50 can be gradually increased. The feed conveyor 50 and the preheating means 50a are surrounded by a heat insulator (not shown) along the longitudinal direction.

In addition, at least one heater 11 is provided inside the main body frame 10. The heater 11 maintains a constant temperature of the glass plate 70 supplied to the main body frame 10 in the state of being preheated by the preheating means 50a. Maintain a constant temperature as shown)

In addition, the cutting edge crack removing device 100 of the present embodiment includes cooling means 60a and auxiliary cooling means 60b for cooling the glass plates 70 moving on the discharge conveyor 60. That is, residual strain is present at the cut edge of the glass plate 70 in which the crack C is removed by the flame f radiated from the burner 30 by being adsorbed by the rotary vacuum adsorption gripper 20. In order to remove this, an annealing operation for slowly cooling the glass plate 70 is required. The cooling rate is preferably maintained at a rate of 14-18 ° C./min up to 350 ° C. and maintained at a rate of 56 ° C.-62 ° C./min from 350 ° C. to room temperature. Cooling means 60a for gradually cooling the glass plate 70 from which the cracks C have been removed include a plurality of

cooling heaters

61a, 61b, 61c, 61d, and 61e provided in the upper direction of the discharge conveyor 60 along the longitudinal direction. , 61f) and cooling air passages 62 respectively installed at one end of the plurality of

cooling heaters

61a, 61b, 61c, 61d, 61e, and 61f. The other end of the cooling air passage 62 is provided with a second blower 63 for supplying external air to the plurality of

cooling heaters

61a, 61b, 61c, 61d, 61e, and 61f to cool the glass plate 70. . That is, by adjusting the amount of air supplied to the discharge conveyor 60, it is possible to adjust the temperature of the air discharged along the longitudinal direction of the discharge conveyor 60 (as shown in the graph of Figure 2, It is possible to gradually cool the temperature of the glass plate 70 transferred by the discharge conveyor 60.

The auxiliary cooling means 60b is installed at a position adjacent to the cooling means 60a. The auxiliary cooling means 60b includes a plurality of connecting

pipes

65a, 65b, 65c, 65d, and 65e installed along the longitudinal direction on the discharge conveyor 60, and a plurality of connecting

pipes

65a, 65b, 65c, 65d, 65e) includes auxiliary cooling air passages 66 which are respectively installed to be connected to one end thereof. The other end of the auxiliary cooling air passage 66 is provided with a third blower 67 for supplying external air to the plurality of connecting

pipes

65a, 65b, 65c, 65d, 65e to cool the glass plate 70. . That is, by adjusting the amount of air supplied to the discharge conveyor 60, it is possible to adjust the temperature of the air discharged along the longitudinal direction of the discharge conveyor 60 (as shown in the graph of Figure 2, The temperature of the glass plate 70 conveyed by the discharge conveyor 60 can be gradually cooled. The discharge conveyor 60, the cooling means 60a and the auxiliary cooling means 60b are surrounded by a heat insulating material (not shown) along the longitudinal direction.

3 and 4, a state in which the glass plate 70 is transferred from the supply conveyor 50 and the discharge conveyor 60 will be described. The

glass plate holders

54c and 64c installed on the supply conveyor 50 and the discharge conveyor 60 support both sides of the glass plate 70 to transfer the glass plate 70 in an inclined state. First, the glass plate 70 is inclined to the glass plate holder 54c and is supplied to the main body frame 10 by the supply conveyor 50. As shown in FIG. 3, the glass plate holder 54c supplied to the main body frame 10 is made to rotate by reaching the position in which the drive sprocket 54a of the supply conveyor 50 was installed. When the glass plate holder 54c rotates, the lower surface of the glass plate 70 which was placed on the glass plate holder 54c is placed on the plate 12a of the glass plate adsorption station 12. The width of the plate 12a of the glass plate adsorption station 12 has a width that can be passed between the pair of guides 54c-2 and 54c-3 of the glass plate holder 54c. Accordingly, the glass plate holder 54c continues to rotate and move together with the chain of the conveyor, and the vacuum suction arm 24 of the vacuum suction gripper 20 rotates to be positioned at the first position and the plate 12a of the glass plate suction station 12 is rotated. A glass plate 70 placed on the substrate is adsorbed and held.

As shown in FIG. 4, the vacuum suction arm 24 descends from the first position to suck the upper surface of the glass plate 70 onto the suction surface 24a to hold the glass plate 70. The glass plate hold 54c rotates around the drive sprocket 54a and the space H between the pair of guides 54c-2 and 54c-3 of the glass plate holder 54c of the glass plate adsorption station 12. The plate 12a is allowed to pass, so that the glass plate holder 54c moves toward the driven sprocket 54b together with the chain. As described above, the glass plate 70 transferred to the glass plate holder 54c of the supply conveyor 50 is inclined by a rotary vacuum adsorption gripper having the lower surface of the glass plate 70 supported by the glass plate adsorption station 12. 20) allow for quick and stable adsorption gripping.

In addition, when the adsorbed glass plate 70 approaches the burner 30 by rotating the rotary shaft 22 of the rotary vacuum suction gripper 20 counterclockwise, the burner 30 and the glass plate 70 collide with each other. It is configured to lower the burner support portion 35 vertically in order to prevent it. When the glass plate 70 adsorbed on the vacuum suction arm 24 is positioned above the flame radiating surface of the burner 30, the burner support part 35 is provided by the burner position adjusting means so that the flame directly contacts the cutting edge of the glass plate 70. It is configured to adjust the angle and direction facing the distance between the glass plate 70 and. In addition, when the vacuum suction arm 24 is rotated 90 ° counterclockwise to a third position, that is, the position where the discharge conveyor 60 is disposed, the vacuum applied to the vacuum suction arm 24 is released to release the glass plate 70. It is comprised so that it may be isolate | separated from the adsorption surface 24a, and may be placed in the glass plate hold 54c of the discharge conveyor 60. As shown in FIG. In order to increase productivity, when the rotary vacuum suction gripper 20 rises to an appropriate position, the rotary vacuum adsorption gripper 20 may be rotated at the same time as the ascension, and even when descending, the rotary vacuum adsorption gripper 20 may be rotated to the proper position.

13 shows a glass plate 70 for removing cut edge cracks C using the apparatus of this embodiment. The glass plate 70 of the present embodiment cut into a predetermined shape forms an upper outer cutting edge 71a on the upper surface 71 and a lower outer cutting edge 72a on the lower surface 72. In addition, the cut surface of the glass plate 70 connects corresponding upper cut edges and lower cut edges, respectively. For example, the cut surface 73 is a surface connecting the upper outer cut edge 71a and the lower outer cut edge 72ab to each other. As shown in FIG. 13, minute cracks C are formed around the cutting edges starting from the cutting edges generated when cutting the glass plate 70.

Referring to Figures 1 to 9 and 14 will be described in detail the process of removing the crack (C) of the cutting edge of the glass plate 70. When the vacuum suction arm 24 sucks the glass plate 70 supplied by the supply conveyor 50 at the first position, and the rotary shaft 22 rotates 90 °, the vacuum suction arm 24 lowers the glass plate 70. The glass plate 70 is transferred to the second position so that the surface 72 faces the flame emitting surface 35b of the burner 30 (FIG. 14A). The flame-radiating surface 35b of the burner 30 blocks portions other than the cutting edge so that the flame f does not come into contact with each other, and a plurality of flame-emitting holes to directly contact the cutting edge and the cutting surface 73 with the flame f. 35c is formed. The lower outer cut edge 72a of the glass plate 70 in contact with the high temperature portion of the flame f and the lower glass of the cut surface 73 are first melted to remove the crack C (FIG. 14B). When a predetermined time elapses while the rotation is stopped, the upper outer cut edge 71a of the glass plate 70 in contact with the low temperature portion of the flame f and the upper glass of the cut surface 73 are melted to remove the crack C. do. When the third position is reached, the vacuum of the vacuum suction arm 24 is released to separate the glass plate 70 onto the discharge conveyor 60. 14D is a partial perspective view of the glass plate 70 with the cut edge crack C removed. When the crack of the cut edge is removed using the apparatus of the present invention, as shown in FIG. 14D, the cut edge 36 of the glass plate 70 has a convex curved shape. In addition, the glass plate 70 has a shape in which the upper outer cutting edge, the lower outer cutting edge, and the side cutting edge are all convex and curved. The crack C is removed to form a convex curved surface, and the glass plate 70 having convex curved cutting edges to which all of the cutting edges are connected has excellent strength by dispersing concentrated stress.

According to the invention, the flame is used to remove fine cracks generated at the cut edges. Therefore, it is possible to completely remove the cracks formed at the cutting edges by local melting of the cutting edges, thereby producing a high quality cut glass plate, and to prevent the occurrence of secondary cracks due to mechanical impact when removing the cracks. There is an effect that can produce this excellent cut glass plate. In addition, it is possible to remove the crack of the glass plate cutting edge without generating any fine glass particles at all can reduce the manufacturing cost by eliminating the cleaning and drying process.

An embodiment of the present invention described above and illustrated in the drawings should not be construed as limiting the technical spirit of the present invention. The protection scope of the present invention is limited only by the matters described in the claims, and those skilled in the art can change and change the technical idea of the present invention in various forms. Therefore, such improvements and modifications will fall within the protection scope of the present invention, as will be apparent to those skilled in the art.

Claims

A burner 30 including a flame radiation surface 35b and a plurality of flame radiation holes 35c formed in the flame radiation surface 35b;

Combustion gas supply means 37 for supplying combustion gas to the burner 30,

The rotating shaft 22 disposed to be perpendicular to the flame emitting surface 35b of the burner 30, the hub 23 fixed to the rotating shaft 22, and one end of the rotating shaft 22 are fixed to the hub 23 and the other end thereof. A rotary vacuum suction gripper 20 having a vacuum suction arm 24 having a suction surface 24a,

The vacuum suction arm 24 is a glass plate, characterized in that the one surface of the glass plate 70 adsorbed and gripped at a predetermined position during the rotation of the rotary shaft 22 toward the flame-radiating surface (35b) of the burner (30) Cutting edge crack removal device.
The method of claim 1,

The rotary vacuum suction gripper 20 includes a plurality of vacuum suction arms 24, and each vacuum suction arm 24 has the suction surface 24a in the vacuum suction section with respect to one rotation of the rotary shaft 22. And a vacuum is applied to the cut edge crack removal device of the glass plate, characterized in that the vacuum applied to the suction surface (24a) is released.
The method of claim 2,

The first position and the second position belong to the vacuum suction section, the third position and the fourth position belong to the vacuum release section with respect to one rotation of the rotary shaft 22,

Each vacuum suction arm 24 is vacuumed on the suction surface 24a at a first position to suck and hold the glass plate 70, and the flame f radiated from the burner 30 at a second position. The glass plate 70 is brought into close proximity to the flame-emitting surface 35b so that the cut edges of the glass plate 70 are in direct contact with each other, thereby removing cracks at the cut edges, and the vacuum is applied to the suction surface 24b at a third position. Cutting edge crack removal device of the glass plate, characterized in that to release the glass plate 70 is released by holding.
The method of claim 3,

A plurality of vacuum passage inlets corresponding to the respective vacuum suction arms 24 are formed at the end of the rotation shaft 22, and extend from the respective vacuum passage inlets to the inside of the rotation shaft 22 to extend the hub 23. And a plurality of vacuum passages are formed in communication with the suction surface (24a) of each vacuum suction arm (24).
The method of claim 1,

Burner 30 so that the flame (f) radiated from the flame radiation hole (35c) of the burner 30 is in contact with the cutting edge of the glass plate 70 adsorbed on the adsorption surface (24a) of the vacuum suction arm (24) Cutting edge crack removal device of the glass plate further comprises a burner position adjusting means for adjusting the position of the glass plate.
The method of claim 5,

The burner position adjusting means includes a shank movement means 33 for moving the burner 30 up and down, and a rotation means 32 for rotating the burner 30. Edge crack removal device.
The method according to any one of claims 1 to 6,

A supply conveyor 50 for continuously supplying the glass plates 70 to the rotary vacuum suction gripper 20,

A discharge conveyor 60 for continuously discharging the glass plates 70 provided from the rotary vacuum suction gripper furnace 20;

Preheating means (50a) for preheating the glass plate (70) moving on the feed conveyor (50),

Cutting edge crack removal apparatus of the glass plate, characterized in that it comprises a cooling means (60a) for cooling the glass plates (70) moving on the discharge conveyor (60) in stages.
The method of claim 7, wherein

The supply conveyor 50 and the discharge conveyor 60 have a plurality of glass plate holders having a pair of guides 54c-2 and 54c-3 configured to support and transport the glass plate 70 in an inclined state. The cut edge crack removal apparatus of the glass plate characterized by further including 54c.
The method of claim 8,

It is further provided with a glass plate adsorption station (12) installed near the supply conveyor (50) for supporting the lower surface of the glass plate (70) supplied from the supply conveyor (50),

The glass plate adsorption station 12 includes a plate 12a for supporting a lower surface of the glass plate 70, and the plate 12a is a pair of guides 54c-2 of the glass plate holder 54c. , 54c-3) cut edge crack removal device of the glass plate, characterized in that configured to pass through the plate (12a) of the glass plate adsorption station (12).
The method of claim 7, wherein

The rotary vacuum suction gripper 20 is cut edge crack removal device of the glass plate, characterized in that configured to be able to move up and down a certain distance.
The method of claim 7, wherein

The preheating means 50a,

Preheating air, which is installed so that one end is connected to the plurality of preheating heaters (51a, 51b, 51c) and the upper portion of the plurality of preheating heaters (51a, 51b, 51c) provided in the longitudinal direction on the supply conveyor 50, respectively. A first blower 53 connected to the other end of the furnace 52 and the preheating air passage 52 to supply external air to the plurality of preheating heaters 51a, 51b, and 51c,

The cooling means 60a,

A plurality of cooling heaters (61a, 61b, 61c, 61d, 61e, 61f) provided in the longitudinal direction on the discharge conveyor 60, and the plurality of cooling heaters (61a, 61b, 61c, 61d, 61e, 61f) Cool air passage 62 is installed so that one end is connected to the upper end, and connected to the other end of the cooling air passage 62 to the outside air to the plurality of cooling heaters (61a, 61b, 61c, 61d, 61e, And a second blower (63) for feeding to 61f).
The method of claim 11,

Further comprising auxiliary cooling means 60b for gradually cooling the glass plates 70 moving on the discharge conveyor 60 at a position adjacent to the cooling means 60a,

The auxiliary cooling means 60b,

One end is provided in the plurality of connecting pipes 65a, 65b, 65c, 65d, 65e and the plurality of connecting pipes 65a, 65b, 65c, 65d, 65e provided along the longitudinal direction on the discharge conveyor 60. It is connected to the auxiliary cooling air passage 66 and the other end of the auxiliary cooling air passage 66 which are respectively installed to be connected to supply external air to the plurality of connecting pipes (65a, 65b, 65c, 65d, 65e) Cutting edge crack removal device of the glass plate, characterized in that it comprises a third blower (67).
The method of claim 12,

The cooling means 60a has a first cooling section in which the temperature falls gently along the longitudinal direction of the discharge conveyor 60, and the auxiliary cooling means 60b is a longitudinal direction of the discharge conveyor 60. Therefore, the cooling air passage 62 and the cutting edge crack removal device of the glass plate, characterized in that the cooling air passage 62 and the auxiliary cooling air passage 66 is installed to increase along the longitudinal direction so that the second cooling section is dropped sharply.
The method of claim 13,

The preheating means (50a) is cut edge crack removal device of the glass plate, characterized in that for preheating the glass plate 70 to a temperature in the range of 500 ℃-630 ℃.
The method of claim 1,

The rotary vacuum suction gripper 20 has a flame edge f of the cut edge contour of the glass plate 70 vacuum-absorbed to the vacuum suction arm 24 radiated from the flame radiation hole 35c of the burner 10. Cut edge crack removal device of the glass plate, characterized in that to maintain the gap between the flame-emitting surface (35b) and the glass plate (70) to be in direct contact with.
The method of claim 15,

The plurality of flame radiating holes (35c) of the burner (10) is circular, the cutting edge crack removal device of the glass plate, characterized in that in the range of 0.1-2 mm.
The method of claim 16,

The plurality of flame radiation holes (35c) is a cutting edge crack removal device of the glass plate, characterized in that the slit shape having a predetermined width.
The method of claim 1,

The combustion gas supplied to the combustion gas supply means (37) is a cutting edge crack removal device of the glass plate, characterized in that the combustion gas containing LNG, LPG, or acetylene gas and oxygen.