JP2006282400A - Forming method for glass article, and forming device therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a press forming method for a glass article where both the cut edge parts of a gob are modified, and shear marks appearing on a forming face are reduced, and to provide a forming device therefor. <P>SOLUTION: In the forming method, fused glass 3 is sagged from a fused glass feed port 1 and is cut into a prescribed amount of fused glass lump 4 by shear blades 2, both the cut edge parts 5, 5 of the fused glass lump 4 formed by the shear blades 2 are abutted on a guide means 10, and are guided and fed thereby to a lower die 7, thus the fused glass lump 26 is press-formed by an upper die. Further, the forming device is provided with: the fused glass feed port 1 of sagging the fused glass 3; a cutting means of cutting the fused glass 3 sagged therefrom into a prescribed amount of the fused glass lump 4 by the shear blades 2; a guide means 10 of being abutted on both the cut edge parts 5, 5 of the fused glass lump 4 formed by the shear blades 2, guiding and feeding the same to the lower die 7; and the upper die of press-forming the fused glass lump 26 in the lower die 7. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a press molding method and a molding apparatus for a glass article, in which a predetermined amount of molten glass is cut with a cutting jig, supplied as a molten glass lump to a lower mold, and pressed with an upper mold to obtain a glass article with a predetermined shape.

  One method of molding glass articles is press molding. As shown in FIG. 6, the press molding is performed by extruding a molten glass 3 melted at a high temperature in a glass melting facility (not shown) from a glass supply port called an orifice 1, and dropping the molten glass 3 called a shear blade 2. This is a method for molding a glass article, which is cut into a molten glass lump called a gob 4 and supplied to a lower mold 7 as a gob 4 and pressed into a predetermined shape by pressing the supplied gob 6 with an upper mold (not shown).

  The shear blade 2 is composed of a pair of cutting blades that are opposed to each other with a molten glass 3 that is extruded from the orifice 1 and hangs down, and is configured to be able to approach and intersect in the horizontal direction. The molten glass 3 that hangs down from the orifice 1 When the amount reaches a predetermined amount, they approach each other toward the molten glass 3 and come into contact with the outer peripheral side surface of the molten glass 3, and then intersect the inside of the molten glass 3 to cut the molten glass 3 to form the gob 4. is there.

  In order to form one gob 4, the shear blade 2 contacts the molten glass 3 twice in the front-rear direction from the horizontal direction. After the previous gob is formed and dropped, the molten glass 3 is extruded from the orifice 1 for the formation of the gob 4. At this time, a cutting trace due to the contact of the shear blade 2 appears at the lower end of the gob 4 which is a boundary with the previous gob, and the molten glass 3 is pushed out to reach a predetermined amount and the shear blade 2 comes into contact again. When the gob 4 is formed, a cutting mark appears at the upper end of the gob 4. The cut marks appearing on the gob 4 are generated because the molten glass 3 is locally cooled by the abutment of the shear blade 2 and the abutment portion is more viscous than the surrounding portion.

  Among the cut marks of the gob 4, the cut mark at the lower end is a process in which the molten glass 3 is extruded from the orifice 1 and hangs down. As the homogenization proceeds, it will be diluted. However, as soon as the gob 4 is formed, it drops toward the lower mold 7, so that the cut traces at the upper end of the gob 4 are homogenized with the surroundings while maintaining high viscosity without eliminating local cooling. As a result, a problematic cutting trace remains at the upper end of the gob 4.

  When the gob 4 is supplied to the lower mold 7 with the cut mark left at such an upper end and press-molded, it appears in the form of dents and wrinkles on the molding surface, which are called shear marks. In particular, in the press molding of CRT glass, appearance defects occur when shear marks appear on the image display surface of the CRT glass. The shear mark can be removed by polishing if it is mild, but in the case of a heavy shear mark, it takes a lot of labor and time to be removed by polishing.

  The cut mark of the gob 4 that causes a severe shear mark is generated by the following mechanism. That is, as shown in FIG. 6, when the molten glass 3 is sheared by the abutting intersection of the shear blade 2 and cut off, the molten glass 3 is pushed and spread in the blade width direction of the shear blade 2, so that the gob 4 Both ends of the cutting trace of this are protruding (hereinafter, this portion is referred to as both cutting ends 5 of the gob 4). Both the cut ends 5 of the gob 4 are portions where local cooling is easy to proceed and the viscosity becomes the highest, and a glass article press-molded using such a gob 4 has a high probability of being severe on the molding surface. A shear mark will appear.

In view of the above, a method has been proposed in which a severe shear mark does not appear on the molding surface of a glass article that has been press-molded by correcting the position of the cut trace of the gob. A gob supply method is shown in which a gob guide made of a flapper or a roller-like rotating body is brought into contact with a cut trace of the gob to deform or bend the cut trace, and then the gob is supplied to the mold.
Japanese Patent Application No. 42-26310 Japanese Utility Model Publication No. 51-79559 Japanese Utility Model Publication No. 51-79560

  However, in the gob supply method disclosed in Patent Documents 1 to 3 which is intended to correct the position of the gob cutting trace, deformation or bending of the gob cutting trace may occur if the contact between the gob and the gob guide is weak. Shear marks appear in the form of dents and wrinkles when they are imperfectly embedded in the molded surface of CRT glass. On the other hand, if the contact between the gob and the gob guide is too strong, the deformation or bending of the cut trace of the gob becomes excessive, and on the contrary, it is transferred to the molding surface of the press-molded CRT glass. For this reason, it must be finely adjusted so that the contact between the gob and the gob guide is appropriately performed, but this adjustment is not easy with the techniques described in Patent Documents 1 to 3.

  Moreover, since the gob guide which consists of a plate-shaped flapper and roller-shaped rotary body of patent documents 1 thru | or 3 contacts a gob from one direction, when it contacts one end part of the cut trace of a gob, the other There is a case where the end portion of the head does not come into contact, and there is a problem that the correction effect is unstable.

  Further, when the gob is brought into strong contact with the gob guide, the gob guide becomes hot due to heat conduction from the gob to the gob guide, causing seizure, and the gob adheres to the gob guide and does not separate. In order to prevent the seizure of the gob guide, oil and grease are applied to the gob contact surface of the gob guide to improve the releasability. However, if the oil and grease are not evenly applied to the gob guide, it is partially applied. As a result, seizure occurs and the mold release effect is diminished, and there is a problem in terms of both stable production and maintenance workability because it is necessary to perform it periodically even during press molding.

  An object of the present invention is to press-mold a glass article, correct a cut mark of a gob, and effectively reduce a shear mark appearing on a molding surface of the press-molded glass article, and the molding thereof. To provide an apparatus.

  As a result of diligent research to solve the above problems, the inventors have made sure that only the cut end portions of both ends of the gob cut trace that are protruding are brought into contact with the gob guide. It is found that it is possible to reduce the shear mark appearing on the molding surface of a glass article that is press-molded by correcting both cut ends of the gob and to prevent the gob guide from being seized. It came to.

  That is, the glass article press molding method of the present invention is formed by dripping molten glass from a molten glass supply port of a glass melting facility and cutting it into a predetermined amount of molten glass lump with a shearing blade of a cutting means. The molten glass lump is guided by bringing both cut ends of the molten glass lump into contact with the guide means to supply the molten glass lump to the lower mold, and the molten glass lump is press-molded with the upper mold. Both the cut ends are formed at the upper end (also referred to as the rear end) when the molten glass lump is cut off by the shear blade.

  As the guide means used in the present invention, any means can be used as long as it reliably comes into contact with both the cut ends of the falling molten glass lump.

  According to the press molding method of the glass article of the present invention, since both the cut ends of the molten glass lump formed by the shear blade are guided by the guide means, both the cut ends of the molten glass lump are guided by the guide means. It is pushed back to the center of the molten glass lump and straightened.

  The glass article press molding method of the present invention is such that when both the cut ends of the molten glass block come into contact with the guide member of the guide means, the respective guide members are retracted by the pressing force acting from the both cut ends. It is characterized by letting you guide.

  As the guide means used in the present invention, the guide members that come into contact with both the cut ends of the molten glass lump are retracted within an appropriate range according to the pressing force acting from both the cut ends of the falling molten glass lump. The molten glass block whose both cut ends are corrected can be used as long as it falls in a posture before contacting the guide member.

  Further, according to the press molding method of the glass article of the present invention, when both the cut ends of the molten glass lump are brought into contact with the guide member of the guide means, the respective guide members are pressed by the pressing force acting from the both cut ends. Since both the cutting end portions of the molten glass lump are given appropriate resistance by contact with the guide member, the molten glass lump is pushed back to the center of the molten glass lump and is suitable for press molding. Corrected to shape.

  The glass article press molding apparatus of the present invention includes a molten glass supply port of a glass melting facility for dropping molten glass, and a molten glass hanging from the molten glass supply port is cut into a predetermined amount of molten glass lump with a shear blade. Cutting means, guide means for guiding the both cut ends of the molten glass lump formed by the shear blade by bringing them into contact with the guide member, and supplying them to the lower mold, and the molten glass in the lower mold And an upper mold for press-molding the lump.

  As the guide means used in the present invention, for example, both the cut ends of the molten glass lump that falls are applied independently at the respective positions so that the guide member is surely brought into contact with both cut ends of the molten glass lump. What is provided so that contact is possible is preferable.

  According to the press molding apparatus for a glass article of the present invention, since it is provided with guide means for guiding both the cut ends of the molten glass lump formed by the shear blade and supplying it to the lower mold, both of the molten glass lump are provided. It becomes possible to carry out the above-mentioned press molding method of the glass article of the present invention in which the cut end is pushed back to the center of the molten glass lump by the guide means and corrected.

  Further, in the press molding apparatus for glass articles of the present invention, the guide means includes guide members arranged opposite to each other across the dropping path of the molten glass lump, each pivotally attached to the base body, and the molten glass lump. When the two abutting portions are brought into contact with each other, they are rotated in directions away from each other about the rotation axis.

  As the guide means used in the present invention, a guide member is pivotally attached to the base so as to be rotatable, and the rotation axis is centered by the pressing force acting from both cutting ends of the molten glass lump in contact with the guide member. Any member can be used as long as it rotates in a direction away from each other within an appropriate range. For example, there are guide members such as an eccentric cam shape and a pendulum shape.

  According to the press molding apparatus for a glass article of the present invention, the guide means is configured such that the guide members arranged to face each other across the dropping path of the molten glass lump are rotatably attached to the base, When the two cut ends are brought into contact with each other in the direction away from each other about the rotation axis, both cut ends of the molten glass lump are given an appropriate resistance force by contact with the guide means, It is pushed back to the center of the molten glass lump and straightened.

  In the press molding apparatus for a glass article according to the present invention, the guide means is located at a position before the guide member contacts the both cut ends of the molten glass lump and then rotates around the rotation axis. It has the return means to return, It is characterized by the above-mentioned.

  As the guide means used in the present invention, each guide member is rotatable about a rotation axis. For example, after the guide member is rotated in contact with both cut ends of the molten glass lump, the guide member is rotated. A spring that presses moderately from the back of the member (string wound spring, leaf spring, etc.), elastic rubber, one that returns by cylinder, one that returns by one rotation, and is mounted in a seesaw shape so that the guide member and balance weight are balanced Those that return after being returned can be used.

  According to the press molding apparatus for a glass article of the present invention, the guide means has return means that rotates and returns to a position before contacting the both cut ends of the molten glass lump. Both cut ends of the molten glass lump can be corrected.

  The glass article press molding apparatus of the present invention is characterized in that the guide means has a rotation adjusting means for adjusting a rotation range of the guide member.

  As the guide means used in the present invention, the guide member is rotated by a stopper that regulates the rotation start angle of the guide member and a spring that applies an appropriate pressing force to the guide member in accordance with the magnitude of the rotation of the guide member. Those that adjust the range can be used.

  According to the press molding apparatus for glass articles of the present invention, the guide means has the rotation adjusting means for adjusting the rotation range of each guide member. The contact force and return time of the guide member that guides the force to act can be freely set.

  The glass article press molding apparatus of the present invention is characterized in that the guide means has an interval adjusting means for adjusting the distance between the guide members.

  As the interval adjusting means used in the present invention, one that adjusts the position by moving the opposing guide members close and apart at equal intervals can be used, and the position between the guide members can be finely adjusted by a screw mechanism or the like. Those are preferred.

  According to the press molding apparatus for a glass article of the present invention, since the guide means has the interval adjusting means for adjusting the distance between the opposing guide members, both the cut ends according to the size of the molten glass lump. It is possible to freely set the distance between the guide members for guiding.

  The glass article press molding apparatus of the present invention is characterized in that the guide means has irregularities on the surface of the guide member.

  As a guide member of the guide means used in the present invention, it can be used as long as irregularities are formed by thermal spraying, blasting, etching or other processing on the surface where both cut ends of the molten glass lump are in contact, A material having poor wettability with glass is preferable.

  According to the press molding apparatus for a glass article of the present invention, since the guide means has irregularities on the surface of the guide member, the contact area between the both cut ends of the molten glass lump and the guide member is reduced, and the melting is performed. Both the cut ends of the glass block do not adhere to the surface of the guide member, and are easily detached from the guide member.

  The glass article press molding apparatus of the present invention is characterized in that the guide means has irregularities made of a hard film on the surface of the guide member.

  As a guide member of the guide means used in the present invention, a wear-resistant alloy such as a cobalt base alloy and a nickel base alloy, a tungsten-carbite system, a tungsten, -The thing with the unevenness | corrugation which consists of hard films, such as a cobalt-type super hard material, is preferable.

  According to the press molding apparatus for a glass article of the present invention, since the guide means has irregularities made of a hard film on the surface of the guide member, both cut ends of the molten glass lump adhere to the surface of the guide member. Therefore, the guide member is easily detached from the surface, and the guide member is not seized, and can be used for a long period of time.

  According to the press molding method and apparatus for a glass article of the present invention, since the guide member is configured to reliably and moderately contact each of the cut ends of the gob, both the cut ends of the gob are separated by the guide member. The shear mark that is guided and pushed back to the center of the molten glass lump and corrected and appears in the press-molded glass article can be reduced. In addition, since the contact action of the guide member to the both cut ends of the gob is optimized, both the cut ends of the gob can be easily detached from the guide member, and the guide member can be prevented from seizing. it can.

  DESCRIPTION OF EMBODIMENTS Embodiments of a glass article press molding method and molding apparatus according to the present invention will be described below in detail with reference to the drawings.

  FIG. 1 is a schematic explanatory diagram of a glass article press molding apparatus of the present invention, FIG. 2 is a schematic diagram of gob guide means constituting a part of the glass article press molding apparatus of the present invention, and FIGS. 3 to 5 are operations of the gob guide means. It is explanatory drawing of.

  As shown in FIG. 1, the press molding apparatus for a glass article of the present invention is one in which a gob guide means 10 is arranged in the middle of a drop path of a gob 4 from an orifice 1 to a lower mold 7. In the figure, the orifice 1, the shear blade 2, and the lower mold 7 are the same as those of the conventional glass article press molding apparatus shown in FIG.

  As shown in FIG. 2, the gob guide means 10 includes a guide plate 11, a guide shaft 12, a guide stopper 13, an adjustment handle 14, a balance weight 15, a guide arm 16, and a mount 17 as guide members. The guide plate 11, the guide shaft 12, the balance weight 15, and the guide arm 16 are each configured as a pair, and are disposed at symmetrical positions with the gob 4 dropping path in between.

  The guide plate 11 is made of a flat plate member, and has an upper end supported by the guide arm 16 and is mounted with a predetermined inclination angle so that the lower end is directed to the falling path of the gob 4. Concavities and convexities made of a hard coating having wear resistance such as tungsten / cobalt are formed on the surface of the guide plate 11 to prevent the gob 4 from sticking and to smoothly separate. The guide plate 11 is a flat plate member, but is not limited thereto, and may be a member having a curved surface or a spherical surface.

  The guide shaft 12 is attached to the gantry 17 so as to be able to approach and move away by the operation of the adjustment handle 14, and the distance between the guide plates 11 can be adjusted according to the size of the gob 4.

  One end of the guide arm 16 is supported by the guide shaft 12 and is rotatable about the guide shaft 12. The guide arm 16 is attached in a seesaw shape so that the guide plate 11 and the balance weight 15 are balanced in a symmetrical position with the guide shaft 12 in between. The guide plate 11 is in contact with both the cut ends 5 of the gob 4. Thus, even if the balance weight 15 is rotated in the direction away from the both cut ends 5 of the gob 4 against the moment of the balance weight 15, it can be pulled back by the balance weight 15 and returned to the original position.

  The guide stopper 13 is attached to the mount 17 so as to be movable up and down above the guide plate 11, and by changing the rotation start angle of the guide plate 11 by moving the guide stopper 13 up and down, both cut ends of the gob 4 are cut. The time when 5 contacts the guide plate 11 and the pressing force acting on the guide plate 11 can be adjusted. When the rotation start angle of the guide plate 11 is set to 70 to 85 degrees with respect to the dropping path of the gob 4, it is preferable because both the cut ends 5 of the gob 4 and the guide plate 11 are appropriately contacted. Further, the guide stopper 13 rotates in a direction away from both the cut ends 5 of the gob 4 when the cut ends 5 of the gob 4 come into contact with each other. The guide plate 11 that is pulled back by 15 and rotates in a direction to return to the original position can be stopped.

  Next, the operation of the above glass article press molding apparatus will be described, and an embodiment of the glass article press molding method of the present invention will be described.

  As shown in FIG. 1, when the molten glass 3 extruded from the orifice 1 and hangs down reaches a predetermined amount, the shear blades 2 opposed to each other across the molten glass 3 approach the molten glass 3 from the horizontal direction. After coming into contact with the outer peripheral side surface of the molten glass 3, the process proceeds toward the inside of the molten glass 3, intersects at the center, and cuts out the molten glass 3 to form the gob 4. At this time, both cut ends 5 are formed at the upper end of the gob 4 by the contact intersection of the shear blade 2.

  The gob 4 starts dropping as it is, but as shown in FIGS. 3 (A), 4 (A), and 5 (A), when the gob guide means 10 provided in the dropping path of the gob 4 is reached, the gob 4 Both cut ends 5 and 5 are in contact with the guide plates 11 and 11. Next, as shown in FIGS. 3 (B), 4 (B), and 5 (B), it receives a pressing action from both cut ends 5 of the gob 4 and is pivotally attached to the guide arm 16 to rotate the guide arm 16. Guide plates 11, 11 attached so as to be rotatable in opposite directions around the moving shaft rotate in a direction away from both cut ends 5, 5 of the gob 4, and both cut ends of the gob 4. 5 is guided downward along the surface of the guide plate 11. At this time, both the cut ends 5 of the gob 4 are regulated by the guide plate 11 and pushed back to the central part of the gob 4. Thereafter, as shown in FIG. 1, the gob 4 falls toward the lower mold 7, is supplied into the lower mold 7, becomes a gob 26, and is pressed by the upper mold (not shown), and is a glass article having a predetermined shape. To be molded.

  On the other hand, when both the cut ends 5 and 5 of the gob 4 are detached from the guide plates 11 and 11, the guide plate 11 is pulled back by the balance weight 15 and rotated by the guide stopper 13 attached above the guide plate 11. It is regulated and returns to the original position shown in FIGS. 3 (A), 4 (A), and 5 (A).

  The above-mentioned press molding method and molding apparatus for glass articles can be applied to molding of articles having the same problems as ceramics and plastics in addition to glass articles.

The schematic explanatory drawing of the press molding apparatus of the glass article of this invention. The schematic of the gob guide means which comprises the press molding apparatus of the glass article of this invention. It is explanatory drawing of operation | movement of a gob guide means, (A) is a perspective view of the state just before both cutting | disconnection edge parts of a gob contact | abut to a guide board, (B) is a state where both cutting | disconnection edge parts of a gob contact | abut, The perspective view of the state which is pressing. It is explanatory drawing of operation | movement of a gob guide means, (A) is a top view which shows the state just before both cutting | disconnection edge parts of a gob contact | abut to a guide board, (B) is a guide plate which both cutting | disconnection edge parts of a gob contact | abut The top view which shows the state which is pressing. It is explanatory drawing of operation | movement of a gob guide means, (A) is a front view which shows the state just before both cutting | disconnection edge parts of a gob contact | abut to a guide plate, (B) is a guide plate which both cutting | disconnection edge parts of a gob contact | abut The front view which shows the state which is pressing. Schematic explanatory drawing of the press molding apparatus of the conventional glass article.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Orifice 2 Shear blade 3 Molten glass 4 Gob 5 Both cutting | disconnection edge parts 6, 26 Gob supplied in lower mold 7 Lower mold 10 Gob guide means 11 Guide plate 12 Guide shaft 13 Guide stopper 14 Adjustment handle 15 Balance weight 16 Guide arm 17

Claims (9)

  The molten glass is suspended from the molten glass supply port of the glass melting equipment and cut into a predetermined amount of molten glass lump with a shear blade of a cutting means, and both cutting ends of the molten glass lump formed by the shear blade are guided means A glass article molding method in which a molten glass lump is guided by being brought into contact with a lower mold and supplied to a lower mold, and the molten glass lump is press-molded with an upper mold.   2. The glass article according to claim 1, wherein when both cut ends of the molten glass lump are brought into contact with the guide member of the guide means, each guide member is retracted and guided by a pressing force acting from both the cut ends. Molding method.   A molten glass supply port of a glass melting facility for dripping molten glass, a cutting means for cutting the molten glass hanging from the molten glass supply port into a predetermined amount of molten glass lump with a shear blade, and a melting formed by the shear blade Guide means for supplying both the cut end portions of the glass lump to the lower mold by guiding them into contact with the guide member, and an upper mold for press-molding the molten glass lump in the lower mold. Glass article molding equipment.   The guide means is configured such that guide members arranged opposite to each other across the dropping path of the molten glass lump are pivotally attached to the base body, and when the both cut ends of the molten glass lump are in contact with each other, The glass article molding apparatus according to claim 3, wherein the glass article molding apparatus rotates in directions away from each other.   The guide means has a return means for returning to a position before the contact by rotating around the rotation shaft after the guide member abuts both cut ends of the molten glass lump. The apparatus for molding a glass article according to claim 4.   The glass article molding apparatus according to any one of claims 3 to 5, wherein the guide means includes a rotation adjusting means for adjusting a rotation range of the guide member.   The glass article molding apparatus according to any one of claims 3 to 6, wherein the guide means includes an interval adjusting means for adjusting a distance between the guide members.   The glass article molding apparatus according to any one of claims 3 to 7, wherein the guide means has irregularities on the surface of the guide member.   The glass article molding apparatus according to claim 8, wherein the guide means has irregularities made of a hard film on a surface of the guide member.

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