JP2005206458A - Method and apparatus for bending glass plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of bending a glass plate by which the glass plate is bent to have an excellent complicated or deeply bent shape and an apparatus for the same. <P>SOLUTION: In the apparatus, a preliminarily forming apparatus 60 comprising a ring 64 for preliminary-forming and a mold 72 for preliminary-forming is mounted in the upstream side of a finally forming apparatus 62 comprising ring 84 for finally forming and a mold 88 for finally forming. The glass plate preliminarily formed to have the prescribed shape by a preliminarily forming apparatus 60 is finally formed to have a final bent shape by the finally forming apparatus 62. In the preliminarily forming apparatus 60, the shape of the ring 64 for preliminarily forming and the shape of the forming surface 73 of the mold 72 for preliminarily forming are formed to have a shape specialized for the preliminarily forming to increase the controllability of the forming to prevent the occurrence of optical defects. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a glass plate bending method and apparatus, and more particularly to a glass plate bending method and apparatus suitable for forming a glass plate heated to a temperature near the softening point into an arbitrary double curved surface shape. .

  In recent years, automotive windowpanes are required to have various shapes and curvatures as the design changes. In particular, the rear glass is a curved glass having a complex curved surface or a deeply bent double curved surface having a larger deformation amount, such as a substantially J-shaped or S-shaped longitudinal section, and the deformation amount is limited to a part of the region. It is requested.

  A press molding method in a heating furnace as one means for producing a curved glass is suitable as a method for producing a curved glass having a complicated shape or a deep bent shape because a glass plate can be bent at a high temperature.

  Conventionally, regarding a press bending method of a glass plate in a heating furnace, a press ring is used as a lower mold on which the glass plate is placed, and the glass plate is deformed by its own weight before breath forming, and thereafter, 2. Description of the Related Art A molding device that presses a glass plate against a molding surface of a mold to perform bending molding is known (for example, Patent Document 1).

According to this bending apparatus, (1) a glass plate heated near the softening point during roller conveyance is placed on the press ring by a transfer machine having a positioning mechanism. (2) The press ring moves to a downstream press position with the glass plate placed thereon, but during that time, the glass plate is deformed by its own weight on the press ring. This deformation is preformed before pressing. (3) At the pressing position, the glass plate is pressed into a predetermined bent shape by the upper male mold and the lower press ring. At this time, the male mold is formed by using vacuum suction together. (4) The glass plate that has been pressed is sucked and held by the male mold and taken out from the press ring, and then placed on a cooling ring that enters from the outside of the furnace on the downstream side, and is carried out of the furnace. Strengthened by the strengthening device. According to this molding apparatus, the glass plate can be molded in a shape that follows the molding surface of the male mold. Therefore, a complex or deep bent glass plate can be obtained by forming the molding surface into a desired shape. .
JP-A 64-52628 (US Pat. No. 4,859,225)

However, the glass plate bending apparatus of Patent Document 1 has the following problems. That is, the amount of glass deformation during the process cannot be arbitrarily controlled, and an optimal molding method cannot be realized. In particular, the press ring has a shape corresponding to the male mold, and when performing the preforming using the same ring, the shape and function are restricted, so that the optimum shape cannot be realized.
As a result, in a shape in which the deformation direction is two directions (double curved surface) or the deformation region is limited, deformation distortion occurs during press molding, which becomes an optical defect. Moreover, since there is only one press ring, the time during which the glass plate stays on the press ring becomes longer. As a result, since the time for the glass plate to occupy the ring becomes long, the manufacturing time per glass sheet cannot be shortened, and the productivity cannot be increased.

  The present invention has been made to solve such problems of the prior art, and provides a glass plate bending method and apparatus capable of bending a glass plate into a complex shape or a deep bent shape with high quality. The purpose is to provide.

  In order to achieve the above object, the present invention provides a glass plate bending method comprising a heating step of heat-softening a glass plate and a bending step of bending the heat-softened glass plate into a predetermined shape. In the bending forming step, the heat-softened glass plate is placed on a preforming support frame that supports an edge portion of the glass plate, and the glass plate is placed in a state of being placed on the preforming support frame. A preforming step for forming the preform into a pre-bending shape, and a glass plate formed into the pre-bending shape were transferred to a main forming support frame that supports the edge thereof, and placed on the main forming support frame. And a main forming step of forming the glass plate into a final bent shape by pressing the glass plate against a forming surface of the main forming mold in a state.

  Moreover, in one aspect of the present invention, the amount of deformation of the glass plate that occurs in the preforming step is 20 to 80% of the amount of deformation of the glass plate that occurs between the heating step and the main forming step. In one embodiment of the present invention, the preforming step and the main forming step are performed in a heating furnace. In one aspect of the present invention, the step of forming the preform into the pre-bending shape includes: (a) a step of pressing the glass plate between the preforming support frame and a preforming mold; and (b) the spare. Sucking the lower surface of the glass plate placed on the forming support frame, (c) heating at least a part of the glass plate placed on the pre-forming support frame, and (d) the spare It is at least any one selected from the step of supporting a part of the glass plate placed on the forming support frame with a ring component that can be raised and lowered, or a combination of two or more.

  Further, the present invention provides a bending apparatus for a glass plate, comprising: heating means for heat-softening the glass plate; and bending means for bending the heat-softened glass plate into a predetermined shape. Includes a preforming support frame on which the heat-softened glass plate is placed and supporting the edge thereof, and means for shaping the glass plate placed on the preforming support frame into a predetermined preformed shape. A pre-forming means, a main-forming support frame on which a glass plate formed in this pre-bending shape is placed and supporting the edge, and a main-molding mold for pressing the glass plate, Provided is a glass plate bending apparatus comprising a main forming means for forming a glass plate into a final bent shape.

  Moreover, in one aspect of the present invention, the amount of deformation of the glass plate generated by the preforming means is 20 to 80% of the amount of deformation finally generated in the glass plate. Moreover, in one aspect of the present invention, the means for forming into the pre-bending shape is (a) a pre-molding mold for pressing the glass plate, and (b) installed below the pre-forming support frame. Means having a suction chamber and air suction means communicating with the suction chamber; (c) means for heating at least a part of the glass plate placed on the preforming support frame; and (d) the preforming. At least one selected from a plurality of ring constituting members constituting the supporting frame and a means provided with a drive means for moving up and down at least one of the ring constituting members, or a combination of two or more is there. Further, in one aspect of the present invention, a plurality of holes are formed in a molding surface of the main molding mold and / or the preforming mold, and after pressing the glass plate, air is passed through the plurality of holes. Is sucked to bend the glass plate.

  In one embodiment of the present invention, the preforming means and the main forming means are installed in a heating furnace. Furthermore, in one aspect of the present invention, a roller conveyor for transporting the heat-softened glass plate, and the glass plate disposed on the most downstream side of the roller conveyor and transported by the roller conveyor by jet air. Floating means for floating, a flat mold for holding the floated glass plate without contacting the glass plate, and positioning means for adjusting the position of the glass plate with respect to the flat mold are further provided.

  As described above, the present invention can realize a desired pre-bending shape with high accuracy by providing a dedicated device for pre-forming. In particular, by providing a support frame dedicated to preforming, an optimal preformed shape can be realized, and optical distortion and wrinkles can be prevented from occurring on the glass plate during the main forming. In addition, since the main forming apparatus can perform another forming of another glass plate while performing the pre-forming in the pre-forming apparatus, productivity can be improved as compared with the conventional case.

  Hereinafter, preferred embodiments of a glass sheet bending method and apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

  A glass sheet bending apparatus 10 according to the first embodiment shown in FIGS. 1 and 2 includes a heating furnace 12, a positioning zone 14, and a forming furnace 16 from the upstream side to the downstream side in the conveying direction of the glass sheet G. The air cooling tempering zone 18 and the carry-out roller conveyor 20 are arranged in order, and the operation timing, heater temperature, and the like of these parts are comprehensively controlled by the controller 11.

  The heating furnace 12 is an electric heating furnace divided into a plurality of zones (including a positioning zone 14 and a forming furnace 16). These electric heating furnaces include a ceiling heater 22a and a floor heater for each electric heating furnace. 22b and a side heater 22c are installed. In some zones, the heater is not shown for convenience of explanation. In each heater, the temperature applied to the glass plate G is set for each electric heating furnace in accordance with the composition, shape, size, thickness, or the like of the glass plate G to be bent.

  The glass plate G is transported in these electric heating furnaces by a roller conveyor 28 and the like, and in the process of transporting the first half part in the electric heating furnace, a predetermined bending temperature (softening point vicinity temperature: for example, 650 to 720). After being heated to (° C.), it is carried into the positioning zone 14.

  The positioning zone 14 includes a hearth bed 30, traveling positioners 32 and 32, and a flat mold 35. The hearth bed 30 is a surface plate having a sufficiently large surface area with respect to the surface area of one surface of the glass plate G, and a large number of air injection holes 33, 33. Yes. Alternatively, an air inlet (not shown) communicating with the air injection holes 33, 33... Is formed in the lower portion of the sbed 30 and a combustion blower (not shown) is connected to the air inlet via a damper (not shown). Has been.

  Therefore, the high-temperature compressed air from the combustion blower is pressure-adjusted by the damper and then injected upward from the air intake through the air injection holes 33, 33. The air pressure at that time is set to such an extent that the glass plate G can be supported by air floating. Therefore, the glass plate G carried into the positioning zone 14 floats from the upper surface of the hearth bed 30 and is supported by air floating.

  The conveyance path formed by the latter half of the roller conveyor 28 and the hearth bed 30 has a slight downward gradient (for example, about 1 to several degrees) toward the downstream (right direction in FIGS. 1 and 2). Therefore, the inertial force given by the roller conveyor 28 and the weight of the glass plate G combine, and the glass plate G moves downstream at a predetermined speed while being supported on the hearth bed 30 by air floating.

  The positioners 32 and 32 are provided at a total of two locations so as to receive the corner portion on the downstream side of the glass plate G that is air-floating supported as shown in FIG. These positioners 32 and 32 are provided movably in the conveying direction of the glass plate G (hereinafter referred to as the X direction) and in the direction perpendicular to the X direction (hereinafter referred to as the Y direction). .

  The tips of the pair of positioners 32 and 32 are formed in a bifurcated shape as shown in FIG. 3, and disks 32a and 32b that contact the edge of the glass plate G are rotatably attached to the lower sides of the bifurcated tips. ing. When the glass plate G enters the positioning zone 14, its leading edge comes into contact with the disks 32a and 32a.

  The positioners 32 and 32 move in the X direction while receiving the glass plate G by the disks 32a and 32a, and at the same time, move the positioners 32 and 32 slightly inward in the Y direction for alignment in the Y direction. The discs 32b and 32b are brought into contact with the corner portion of the glass plate G, and the glass plate G is moved in the Y direction by a small amount. Thereby, the Y direction position of the glass plate G is positioned. Therefore, the glass plate G is positioned in the X direction and the Y direction in the positioning zone 14. This positioning is performed in order to accurately align the position of the glass plate G with the position of a preforming support frame (described later) disposed in the molding furnace 16 of FIGS. The glass plate G positioned by the positioners 32 and 32 is sucked and held by the flat mold 35 and then conveyed vertically above the preforming support frame 64.

  3 and 4 includes the ball screw device 34 arranged in the X direction, the ball screw device 36 arranged in the Y direction, and the like. . A feed screw 38 of the ball screw device 34 is provided along a base 40 disposed in the X direction, and a nut 42 of the ball screw device 34 is formed at a lower portion of the X block 44. The X block 44 is screwed to the feed screw 38 via the nut 42 and is supported by a pair of rails 46, 46 disposed along the base 40 so as to be movable in the X direction. Therefore, when the motor 34A of the ball screw device 34 is driven forward or backward, the X block 44 moves in the X direction.

  A feed screw 48 indicated by a broken line in FIG. 4 is provided on the upper surface of the X block 44 along the Y direction. Further, the nut 50 of the ball screw device 36 is formed below the Y block 52. The Y block 52 is screwed to the feed screw 48 via the nut 50 and is supported by a pair of rails 54, 54 disposed on the upper surface of the X block 44 along the Y direction so as to be movable in the Y direction. Yes.

  Therefore, when the motor 36A of the ball screw device 36 is driven forward or backward, the Y block 52 moves in the Y direction. Therefore, when the ball screw devices 34 and 36 are driven, the positioner 32 fixed to the Y block 52 moves in the X direction and the Y direction. In the positioning zone 14 as well, an electric heater (not shown) is installed on the furnace wall, side wall, and hearth above the hearth bed 30 in order to keep the glass plate G being positioned at a high temperature.

  On the other hand, the flat mold 35 shown in FIG. 2 is a surface plate having a sufficiently large surface with respect to the surface area of one surface of the glass plate G, and a plurality of air injection / suction holes ( (Not shown) are densely formed. An air intake (not shown) communicating with these air injection / suction holes is formed in the upper part of the flat mold 35, and a combustion blower (not shown) is connected to the air intake via a damper (not shown). And air suction means are connected.

  Further, the flat mold 35 is moved by a conveying means (not shown) between the position shown by the solid line in FIG. 2 and a preforming device (corresponding to the preforming means in the claims) 60 (two-dot chain line in FIG. 2). It is configured to be able to reciprocate between the positions indicated by.

  The molding furnace 16 communicates with the positioning zone 14, and the inside thereof is maintained in a high temperature state that can be bent and molded by a heater (not shown) as in the positioning zone 14. Further, as shown in FIG. 5, a pre-forming device 60 is installed on the upstream side in the forming furnace 16, and a main forming device (corresponding to the main forming means in the claims) 62 is installed on the downstream side of the pre-forming device 60. ing.

  Here, a procedure for delivering the glass sheet G from the positioning zone 14 to the preforming device 60 will be described. First, in a state where the glass plate G is positioned in the positioning zone 14, the flat mold 35 descends and holds the glass plate G by suction. In that case, the air pressure injected from the air injection holes 33, 33... Of the hearth bed 30 is higher than the state in which the glass plate G is air-floating, and assists the adsorption and holding of the glass plate G by the flat mold 35. . Then, the glass sheet G is carried into a position above the preforming support frame 64 that is one configuration of the preforming device 60 in the molding furnace 16 while being held by suction by the flat mold 35. The glass plate G transported to the upper position of the preforming support frame 64 falls by releasing the suction holding by the flat mold 35 and is placed on the preforming support frame 64. Note that the preforming support frame 64 moves in the direction of the flat mold 35 immediately before the glass plate G is placed. Therefore, the placement of the glass plate G is indicated by a two-dot chain line in FIG. Done in position.

  The preforming support frame 64 of the preforming device 60 is formed in a shape along the outline of the glass plate G so as to support the periphery (the end surface or the vicinity of the end surface) of the glass plate G. The preforming support frame 64 may support the entire circumference of the glass plate, or may support a part of the entire circumference. The preforming support frame 64 is installed on an upper portion of a shuttle 66 made of steel. The legs of the shuttle 66 extend to the lower part of the hearth 68 through a slit (not shown) provided in the hearth 68 and are supported by the rail 70 so as to be movable in the X direction. Therefore, when the preforming support frame 64 moves to the position indicated by the two-dot chain line in FIG. 2, the glass sheet G conveyed from the positioning zone 14 is placed on the preforming support frame 64. The Thereafter, the preforming support frame 64 is moved rightward in the figure by a conveying means (not shown) (for example, a timing belt driving device), and at the position indicated by the solid line in FIG. Stop at the position directly below.

  On the other hand, the preforming mold 72 is supported on the ceiling portion of the molding furnace 16 so as to be movable up and down via a lifting means (not shown) (for example, a hydraulic cylinder). The molding surface 73 of the preforming mold 72 is made so that the planar size thereof corresponds to substantially the entire surface of the glass plate G. Further, as shown in FIG. 6, the molding surface 73 whose longitudinal section is curved like an S-shape is provided with air holes 74, 74... Over the entire surface, and each air hole 74 is hollow in the preforming mold 72. It communicates with the air path 76 which is a part. The air path 76 is connected to an air pump 80 via a duct 78.

  Therefore, by driving the air pump 80 to the ejection side or the suction side, air can be ejected from each air hole 74 in FIG. 6 or air can be sucked from each air hole 74. By sucking air from each air hole 74, the glass plate G is sucked and held on the molding surface 73 of the preforming mold 72. In addition, when injecting air from the air hole 74, in order to prevent the glass plate G from being cooled, it is necessary to provide a heater for raising the temperature of the air (even if the remaining heat of the heating furnace 12 is used). Good). The molding surface 65 of the preforming support frame 64 (surface that supports the edge of the glass plate G) 65 has a shape in which the molding surface 73 of the preforming mold 72 is substantially inverted. Further, the preforming mold 72 is fixed to the lower portion of the gantry 82, and the gantry 82 is connected to the elevating means so as to be movable up and down.

  The shapes of the molding surfaces 65 and 73 of the preforming support frame 64 and the preforming mold 72 are shallower than those of the molding apparatus 62. That is, the deformation amount of the glass plate G in the preforming is preferably 20 to 80%, more preferably 20 to 50% of the deformation amount until the flat glass plate is deformed to the final shape. In this case, it is preferable to define the amount of cross-curvature of the glass plate G as a parameter. The amount of doubling is defined as the largest shape error obtained by comparing the desired design shape with the shape of the actually produced glass plate. Further, it may be determined based on the curvature at a part in the plane of the glass plate having the greatest degree of deformation (such as a part where the tensile force generated at the time of bending is maximized), or an average value of curvatures at a plurality of points may be used as a reference. It may be determined as In any case, the preform may be preformed in the range of 20 to 80% of the final curvature. By performing such preliminary molding, an excessive force is not applied to the glass plate G during the main molding, and problems such as wrinkles on the glass plate and optical distortion can be prevented.

  The glass plate G preformed in a predetermined bending shape by the preforming device 60 is sucked and held by the preforming mold 72 and then moved to a position directly below the preforming mold 72. It is placed on a molding support frame 84 (see FIG. 5). At this time, the preforming support frame 64 has moved to the position indicated by the two-dot chain line in FIG.

  The main forming support frame 84 preferably has a shape and size with which the peripheral edge of the glass plate G is in contact with the entire surface. Further, the main support frame 84 is installed on the upper portion of the shuttle 86. The legs of the shuttle 86 pass through the hearth 68 and are attached to the rail 70 so as to be movable in the X direction. Therefore, after the support frame 84 for main molding has moved to the receiving position, which is directly below the preforming mold 72, when the suction holding of the preforming mold 72 is released, the preformed glass sheet G Falls and is placed on the main forming support frame 84. In this state, the main forming support frame 84 moves to the right in the figure, and is positioned at the position indicated by the solid line in FIG. 5, that is, directly below the main forming mold 88. The main support frame 84 and the shuttle 86 are moved by, for example, a timing belt driving device.

  The molding mold 88 is supported on the ceiling of the molding furnace 16 so as to be movable up and down via lifting means (not shown) (for example, a hydraulic cylinder). The molding surface of the main molding mold 88 is formed so that the plane size thereof corresponds to substantially the entire surface of the glass plate G, and the shape thereof is formed to have a larger curvature than the preforming mold 72. In addition, air holes are formed on substantially the entire surface of the molding surface 89 that is convexly curved below the main molding mold 88 in the same manner as the preforming mold 72. Each air hole communicates with an air path that is a hollow portion of the main mold 88, and the air path is connected to an air pump 92 via a duct 90 shown in FIG.

  Therefore, by driving the air pump 92 to the ejection side or the suction side, air can be ejected from each air hole or air can be sucked from each air hole. By sucking air from each air hole, the glass plate G is sucked and held on the molding surface 89 of the main molding mold 88. In addition, when injecting air from an air hole, it is necessary to provide a heater for increasing the temperature of the air as in the preforming mold. Further, the molding surface 85 of the main molding support frame 84 (the surface that supports the peripheral edge of the glass plate G) 85 is formed in a shape that is substantially inverted from the molding surface 89 of the main molding mold 88.

  The shape of the molding surface 89 of the main mold 88 is preferably substantially the same as the product shape of the glass plate G when bent outside the furnace. However, in the case of the in-furnace bend forming apparatus 10 that bends and forms in the forming furnace 16 as in the present embodiment, the glass plate G is deformed by its own weight in the process of being conveyed to the strengthening zone 18 after bend forming. In anticipation of this, it is preferable to make the amount slightly different from the product shape of the glass plate G.

  The air-cooling strengthening zone 18 shown in FIG. 2 includes a quench shuttle 94, an air-cooling strengthening device 96, and the like. The quench shuttle 94 has a quench ring 97 fixed to the left side and a catch member 98 fixed to the right side.

  The quench ring 97 is for receiving the glass plate G bent in the forming furnace 16, and is formed in the peripheral shape of the glass plate G substantially matching the bent shape of the curved glass plate to be formed. The quench ring 97 is configured such that the quench shuttle 94 reciprocates in the X direction, so that the position directly below the molding mold 88 in the molding furnace 16 (receiving position) and the air cooling strengthening position (delivery position) by the air cooling strengthening device 96 are provided. ).

The air-cooling strengthening device 96 includes an upper air outlet head 100 and a lower air outlet head 102, and injects cooling air supplied from a blower (not shown) onto both the upper and lower surfaces of the glass plate G, respectively. The glass plate G is positioned at the air-cooling strengthening position between the upper blowing head 100 and the lower blowing head 102 while being supported by the quench ring 97, and then sprayed from the upper blowing head 100 and the lower blowing head 102. Air cooling is enhanced by the cooling air. Further, the cooling air pressure by the lower outlet head 102 is set to a pressure at which the glass plate G can be supported by air floating.
Thereby, the glass plate G positioned at the air-cooling strengthening position is air-cooled and strengthened in a state of being supported by air floating. During this time, the quench shuttle 94 moves to the left in FIG. 2 and is located at the aforementioned receiving position.

  On the other hand, the catch member 98 is for receiving the glass plate G that has been air-cooled and tempered in a state where the air-floating is supported at the air-cooling tempering position. doing. The catch member 98 reciprocates between the air cooling strengthening position (receiving position) and the entrance position (delivery position) of the carry-out roller conveyor 20 as the quench shuttle 94 reciprocates in the X direction.

  The quench shuttle 94 is reciprocated in the X direction by a horizontal movement device (not shown) such as a chain drive device or a timing belt drive device.

  An air floating device 104 is installed at the delivery position. By the air jetted from the upper surface of the air floating device 104, the glass sheet G after the air cooling strengthening that has been conveyed to the delivery position floats and is pressed against the stopper 106.

  During this time, the quench shuttle 94 moves to the left in FIG. 2 and is located at the receiving position described above. In the air floating device 104, the glass pressure G that is supported by the air floating is quietly placed on the carry-out roller conveyor 20 by controlling the air pressure to gradually decrease.

  Next, the operation of the glass sheet bending apparatus 10 according to the first embodiment will be described.

  First, while conveying a flat glass plate G cut to a size and shape corresponding to the rear glass of an automobile to the first half of the heating furnace 12 by the roller conveyor 28 (upstream side (left side) in FIG. 2), The heater is heated to a predetermined bendable temperature. Then, the glass plate G is carried into the positioning zone 14 from the first half of the heating furnace 12 by the roller conveyor 28.

  Next, the glass plate G carried into the positioning zone 14 is supported in an air floating manner by the hearth bed 30, and the positioners 32 and 32 are brought into contact with the edge of the glass plate G in the air floating state to It is positioned at a predetermined position that matches the preforming support frame 64.

  Next, the glass plate G is sucked and held by the flat mold 35, and the flat mold 35 is moved toward the molding furnace 16, whereby the positioned glass plate G is carried into the molding furnace 16.

  In the molding furnace 16, the preforming support frame 64 is waiting at the receiving position. When the glass plate G is positioned above the pre-forming support frame 64, the movement of the flat mold 35 is stopped and the suction holding is released, and the glass plate G is removed. It is placed on the support frame 64 for preforming. Thereafter, when the preforming support frame 64 moves to a position directly below the preforming mold 72, the preforming mold 72 moves downward, and the glass sheet G is pressed by the preforming support frame 64 and the preforming mold 72. Then, it is preformed into a predetermined bent shape. By this preforming, the glass plate G is bent to 20 to 80% of the final shape.

  Next, the preformed glass plate G is vacuum-sucked and held by the preforming mold 72 and taken up from the preforming support frame 64. Then, while the glass plate G is adsorbed to the preforming mold 72, the preforming support frame 64 moves to the receiving position to receive the next glass plate G, and in conjunction with this, the main forming support The frame 84 moves directly below the preforming mold 72.

  Next, the vacuum suction holding by the preforming mold 72 is released, and the preformed glass sheet G is placed on the main forming support frame 84. Then, the main forming support frame 84 is moved directly below the main forming mold 88. At this time, the preforming support frame 64 that has received the next glass plate G also moves directly below the preforming mold 72.

  Next, the preformed glass plate G is pressed by the main forming support frame 84 and the preforming mold 88 to be formed into a final shape. On the other hand, at this time, the second glass plate G is preformed in the preforming device 60.

  Next, the glass plate G is vacuum-held by the main molding mold 88 and taken up from the main molding support frame 84. Then, the main forming support frame 84 moves directly below the preforming mold 72, the door 12 </ b> A opens in conjunction with this, the quench ring 97 enters the forming furnace 16, and immediately below the main forming mold 88. Stop. After that, the vacuum suction holding by the main molding mold 88 is released, and the glass plate G which is finally molded is placed on the quench ring 97. At substantially the same time, the vacuum suction holding by the preforming mold 72 is released, and the preformed glass plate G is placed on the main forming support frame 84.

  Then, the formed glass sheet G is carried out of the furnace by the quench ring 97, cooled and strengthened by the air cooling and strengthening device 96, received by the catch member 98, and conveyed to the entrance of the carry-out roller conveyor 20. The glass plate G is conveyed to the downstream inspection unit or packing unit by the carry-out roller conveyor 20. During this time, the second glass plate G is subjected to main forming and air cooling strengthening, and the third and subsequent glass plates G are continuously processed through the bending process described above.

  As described above, the glass sheet bending apparatus 10 according to the first embodiment includes the dedicated apparatus 60 for preforming, thereby realizing a desired preformed shape with high accuracy. In particular, by providing the support frame 64 dedicated to preforming, the reproducibility of the preforming shape can be enhanced. Further, the main forming can be performed in the main forming apparatus 62 while the pre-forming is performed in the pre-forming apparatus 60, and the productivity can be greatly improved as compared with the prior art.

  Next, other embodiments of the present invention will be described.

  7 to 12 show the internal structure of the forming furnace 16 of the bending apparatus of the second to sixth embodiments. In these forming furnaces 16, the main forming apparatus 62 arranged on the downstream side is shown. Since it is the same structure as the main molding apparatus 62 described in the first embodiment, the description thereof is omitted here, and the structure and operation of the preforming apparatuses 150, 200, 250, 300, and 350 having different structures will be described.

  A preforming apparatus 150 shown in FIG. 7 is provided with a female mold 152 in place of the preforming support frame 64. As shown in FIG. 8, the female mold 152 has a molding surface 153 that follows the molding surface 73 of the preforming mold 72 on the upper surface thereof. This molding surface 153 has a sufficient surface area with respect to the surface area of the glass plate G, and air holes 154, 154... Are densely formed on the molding surface 153. These air holes 154, 154... Are connected to the air pump 160 via an air path 156 that is a hollow portion of the female mold 150 and an air pipe 158, and when the air pump 160 is driven, the air in the air path 156. Is sucked. As a result, the preformed glass plate G is sucked and held on the molding surface 153 of the female mold 152. The air pipe 158 is connected to the air pump 160 via the flexible pipe 162 as shown in FIG. 7 and allows the shuttle 66 to move in the X direction by the expansion and contraction of the flexible pipe 162.

  This preforming apparatus 150 performs preforming of the glass plate G by self-weight deformation of the glass plate G and vacuum by the female mold 152. That is, (a) the glass plate G heated in the vicinity of the softening point or higher than the softening point in the heating furnace is placed on the female mold 152 by the flat mold 35.

  (B) The glass plate G placed on the female mold 152 is deformed by its own weight, and is preformed by local vacuum suction by the female mold 152. In the pre-molding, molding is performed up to 20 to 80% of the final shape.

  (C) When the preforming is being performed, the female mold 152 moves directly below the preforming mold 72. The preforming mold 72 also has a function of pressing the glass plate G. Here, the preforming mold 72 has a function of picking up the glass plate G preformed by the female mold 152 from the female mold 152, so that it is adsorbed. It can also be called a mold. Therefore, the preforming mold (adsorption mold) 72 shown in FIG. 8 is designed to be simplified and reduced in weight by specializing in vacuum adsorption as compared with the preforming mold 72 shown in FIG. Therefore, (d) the glass sheet G after the preforming by the female mold 152 is vacuum-sucked by the preforming mold (adsorption mold) 72 and taken up from the female mold 152.

  (E) When the glass plate G is adsorbed to the preforming mold (adsorption mold) 72, the main forming support frame 84 moves directly below the preforming mold (adsorption mold) 72. Since the subsequent steps are the same as those of the bending apparatus 10 of the first embodiment, they are omitted here.

  Thus, according to the preforming apparatus 150 that performs the preforming by the female mold 152 by the self-weight deformation and the forced deformation due to the suction, in the shape of drooping downward like an egg shape, the preforming means is not a press but a female. By using the vacuum of the mold 152, preforming with good optical quality can be realized without locally increasing the amount of distortion. By applying vacuum suction to a portion that is particularly difficult to bend in the molding process, it can be reliably molded into a predetermined shape. As a result, the shape stability in production is increased and the molding range is expanded.

  Further, by applying the female mold vacuum system of FIG. 7, a suction chamber is installed below the preforming support frame 64, and a suction pump (corresponding to the air suction means in the claims) is connected to the suction chamber. An apparatus may be used in which the glass plate G placed in close contact with the edge of the preforming support frame 64 is bent to perform preforming by sucking the air in the suction chamber with a suction pump.

  A preforming apparatus 200 shown in FIG. 9 is provided with a local heater (corresponding to the heating means of claim 6) 202 in place of the preforming mold 72. The local heater 202 is attached to a predetermined position on the lower surface of the header 204 installed just above the preforming support frame 64, and its temperature is set to an appropriate value according to the thickness of the glass plate G. The local heating heater 202 particularly concentrates and heats the deep bending portion of the glass plate G placed on the preforming support frame 64, thereby promoting softening of the deep bending portion, and the preforming support frame 64. The pre-forming of the glass plate G at is promoted. Further, instead of the heater 202, a gas burner such as acetylene may be used.

  According to this preforming apparatus 200, the main preforming is deformation due to its own weight, but the local heater 202 intentionally gives a temperature distribution to the glass plate G. As a result, the viscosity distribution of the glass plate G is controlled to control the amount of deformation of its own weight so that optical distortion does not occur.

  That is, (a) the glass plate G heated to the softening point or higher in the heating furnace is placed on the preforming support frame 64 by the flat mold 35. (B) The preforming support frame 64 moves directly below the local heater 202. (C) The local heater 202 is lowered to heat the glass plate G on the preforming support frame 64 and raise the temperature of the deep bent portion where the deformation is large. Although the glass plate G is deformed by its own weight, the deep bent portion having a high temperature has a large amount of deformation. This promotes preforming.

  The local heater 202 is a component that is mounted in exchange for the preforming mold 72. An arbitrary portion can be limitedly heated by changing the height of the heater 202 relative to the glass G. Moreover, you may make it prevent that except a desired site | part is heated by using a heat shield.

When the preforming is completed, (d) the local heater 202 is raised and retracted.
(E) The preforming support frame 64 moves directly below the main mold 88. (F) The main mold 88 is lowered, and the glass G is held by vacuum suction by the main mold 88 and taken up from the preforming support frame 64. (G) The main forming support frame 84 moves directly below the main forming mold 88. (H) The main molding mold 88 descends, and the glass plate G is pressed between the main molding support frame 84 and main molding is performed. Since the subsequent steps are the same as those of the bending apparatus 10 of the first embodiment, they are omitted here.

  Thus, according to the preforming apparatus 200 that performs preforming by the preforming support frame 64 and the local heater 202, when the amount of deformation required for the glass sheet G differs depending on the location, the amount of deformation is locally locally reduced. A shape having a large region can be deeply deformed by its own weight into a desired shape by locally heating the portion with the local heater 202 to reduce the viscosity of the glass sheet G. Further, since the stress generated during the molding can be reduced by controlling the temperature of the heater 202, that is, the self-weight deformation amount of the glass plate G can be suppressed to the self-weight deformation amount in which optical distortion does not occur. Quality deterioration can be prevented, and the molding range is expanded.

  A pre-forming device 250 shown in FIG. 10 is provided with a pre-forming support frame 254 in which a plurality of ring constituent members 252, 252... Independently move up and down instead of the pre-forming support frame 64. Are attached to pistons 258, 258, etc. of a cylinder device 256 attached to the shuttle 66, and are independently moved up and down by independent expansion and contraction operations of the pistons 258, 258, and so on. The glass plate G is bent by its own weight.

  According to this preforming apparatus 250, the main preforming is deformation due to its own weight, but the height position of the ring constituent members 252, 252. By changing based on the above, it is possible to control the time-dependent progression of the weight deformation of the glass plate G and the self-weight deformation of the deep bent portion.

  That is, (a) glass G heated to the softening point or higher in the heating furnace is placed on the preforming support frame 254 by the flat mold 35. (B) Various shapes of ring constituent members (glass receiving members) 252, 252... Are attached to the preforming support frame 254 inside a normal ring. It moves up and down, and preforming by its own weight is executed. (C) While the preforming is performed, the preforming support frame 254 moves directly below the preforming mold 72.

  (D) The preformed glass G is vacuum-sucked by the preforming mold 72 and taken up from the preforming support frame 254. Since the preforming mold 72 has a function of picking up the glass sheet G preformed by the preforming support frame 254 from the preforming support frame 254, the preforming mold 72 may be referred to as an adsorption mold. it can. Therefore, compared with the preforming mold 72 shown in FIG. 6, the preforming mold (adsorption mold) 72 is specialized in vacuum suction and is simplified and reduced in weight.

  (E) When the glass plate G is adsorbed to the preforming mold (adsorption mold) 72, the main forming support frame 84 moves directly below the preforming mold (adsorption mold) 72. Since the subsequent steps are the same as those of the bending apparatus 10 of the first embodiment, they are omitted here.

  According to such a preforming apparatus 250, the plurality of ring constituent members 252, 252,... Are moved up and down, and the height position thereof is controlled, whereby the self-weight deformation of the glass plate G can be advanced stepwise. .

  The preforming apparatus 300 shown in FIG. 11 is provided with the female mold 152 of FIG. 7 in place of the preforming support frame 64 and the local heater 202 of FIG. 9 in place of the preforming mold 72. is there.

  According to this preforming apparatus 300, preforming is performed by self-weight deformation of the glass plate G and vacuum adsorption by the female mold 152 while heating a region having a large deformation amount by the local heater 202.

  That is, (a) the glass plate G heated above the softening point in the heating furnace is placed on the female mold 152 by the flat mold 35. (B) The female mold 152 moves directly below the local heaters 202, 202. (C) The local heaters 202, 202... Are lowered to locally heat the glass plate G. In parallel, the self-weight deformation and the local deformation by the female mold 152 proceed, and the preform is preformed. (D) After completion of the preliminary molding, the glass plate G moves to a position immediately below the main molding mold 88 and is held by suction by the main molding mold 88. (E) The main forming support frame 84 moves directly below the main forming mold 88. (F) The main molding mold 88 is lowered, and the glass plate G is pressed between the main molding support frame 84 and the main molding is performed. Since the subsequent steps are the same as those of the bending apparatus 10 of the first embodiment, they are omitted here.

  According to such a preforming apparatus 300, by combining the local heating by the local heater 202 and the vacuum by the female mold 152, the viscosity of the region to be largely deformed by vacuum suction can be lowered. As a result, it is possible to realize a larger amount of local deformation than when each acts alone, and furthermore, it is possible to suppress the influence of distortion and the like on the peripheral region, thereby improving the shape quality.

  12 is provided with the preforming support frame 254 of FIG. 10 instead of the preforming support frame 64, and the local heater 202 of FIG. 9 is installed instead of the preforming mold 72. It is a thing.

  The preforming device 350 controls the preforming by vertically moving the ring constituent members 252, 252... Constituting the preforming support frame 254 while heating the region having a large deformation amount by the local heater 202.

  That is, (a) the glass plate G heated to the softening point or higher in the heating furnace is placed on the preforming support frame 254 by the flat mold 35. (B) The preforming support frame 254 is moved directly below the local heaters 202, 202. (C) The local heaters 202, 202... Are lowered to locally heat the glass plate G. Although the self-weight deformation proceeds in parallel, the progress of the self-weight deformation amount is controlled by controlling the vertical positions of the ring constituent members 252, 252... Of the preforming support frame 254. (D) After completion of the preliminary molding, the glass plate G moves to a position immediately below the main molding mold 88 and is held by suction by the main molding mold 88. (E) The main forming support frame 84 moves directly below the main forming mold 88. (F) The main molding mold 88 is lowered, and the glass plate G is pressed between the main molding support frame 84 and the main molding is performed. Since the subsequent steps are the same as those of the bending apparatus 10 of the first embodiment, they are omitted here.

  According to this preforming apparatus 350, the local heating by the local heater 202 and the vertical movement of the ring constituent members 252, 252,... It can be finely controlled. As a result, it is possible to realize a more complicated deformation amount distribution than when each of them operates alone. By linking the time for operating each part of the local heater 202 and the vertical movement of the ring component 252, an arbitrary position can be set as the inflection point of the curved surface, and a complicated shape including an asymmetric shape can be obtained. It can be preformed and the molding range is expanded.

  Further, instead of the hard member preforming mold 72, a balloon-type bending means for inflating a balloon and pre-forming the glass plate G with the surface pressure may be applied. According to this preforming apparatus, since a uniform surface pressure acts on the sheet-like glass plate G, the amount of distortion becomes uniform over the entire surface, which is suitable for forming a shape close to a sphere. Furthermore, since the disadvantage that the high surface pressure is locally generated and the glass plate G is distorted can be avoided, the optical quality is improved and the molding range is expanded.

  Moreover, you may apply the preforming apparatus which pre-bend-forms so that the ring structural member 252,252 ... of the support frame 254 for preforming may be moved up and down, and the glass plate G may be rolled.

  FIGS. 13A to 13D are explanatory views showing the arrangement of the preforming means and the main forming means. FIG. 4A shows that a pre-forming means (pre-forming mold 72 and pre-forming support frame 64) and a main forming means (main forming mold 88 and main forming support frame 84) are installed in a heating furnace 400. An example is shown. In FIG. 5B, outside the heating furnace 401, pre-forming means (pre-forming mold 72 and pre-forming support frame 64) and main forming means (main forming mold 88 and main forming support frame 84) are installed. An example is shown. FIG. 6C shows that a pre-forming means (pre-forming mold 72 and pre-forming support frame 64) is installed in the heating furnace 402, and a main forming means (main forming mold 88 and main forming is formed outside the heating furnace 402. An example in which a support frame 84) is installed is shown. In FIG. 4D, a pre-forming means (pre-forming mold 72 and pre-forming support frame 64) is installed outside the heating furnace 403, and the main forming means (the main forming mold 88 and the main forming mold) are provided in the heating furnace 404. An example in which a support frame 84) is installed is shown.

  Any configuration is included in the present invention. The one provided with the forming means in the furnace is advantageous in that the temperature of the glass plate can be kept constant, and the one provided with the forming means outside the furnace is advantageous in that the support frame and the mold can be easily exchanged. Which arrangement is adopted is appropriately selected based on the relationship between these advantages and the type (size, shape, application, etc.) of the glass plate to be produced.

  14A to 14C are explanatory views showing other forms of means for transferring the heat-softened glass plate to the preforming support frame. As shown in FIG. 5A, the roller conveyor 28 for conveying the heated and softened glass plate G, the floating means 28a for floatingly supporting the glass plate G, and the glass plate G are held in a separated state. And a flat mold 35a. The glass plate G conveyed by the roller conveyor 28 passes through the upper surface of the floating means 28a due to inertia (FIGS. 14A and 14B). At that time, the air supplied by the blower 28b is sprayed from countless openings provided on the upper surface of the floating means 28, so that the glass plate G reaches the lower surface of the flat mold 35a while floating.

  On the other hand, the flat mold 35a has innumerable openings on the lower surface thereof, and either the blower 35b or the vacuum source 35c is connected to each opening. The number of openings connected to the blower 35b is substantially the same as the number of openings connected to the vacuum source 35c. By simultaneously performing suction and exhaust through these openings, the lower surface of the flat mold 35a is approached. The glass plate G can be held without dropping and without contacting the flat mold 35a. Further, the glass plate G held by the flat mold 35a further proceeds in the right direction in the figure due to inertia.

  Further, near the lower surface of the flat mold 35a, positioners 32a ′, 34a ′ and 32b ′, 32b ′, to which the drive units 341 to 344 are individually connected, stand by (FIG. 15). Positioning in the conveyance direction of the plate G is performed, and positioning in a direction orthogonal to the conveyance direction of the glass plate G is performed by the positioner 32b ′ (the arrow in the figure indicates the movement direction of the positioner). When the glass plate G stops at a predetermined position, the glass plate G is dropped and placed on the preforming support frame 64 by stopping the suction by the flat mold 35a (FIG. 14 (c)). .

  16 (a) is a side view showing a preforming support frame, FIG. 16 (b) is a side view showing a main forming support frame, and FIG. 16 (c) is a preforming support frame (or main forming support frame). It is a top view which shows an example of the positional relationship of a glass plate. As shown in FIGS. 4A and 4B, the frames 64 and 84 have different inclination angles in order to change the deformation amount of the glass plate in the pre-forming and the main forming. When the inclination angles of the respective frames are θ1 and θ2, the relationship θ1 <θ2 is established. Further, the glass plate G is placed on the ring-shaped frame 64 (or 84). Note that the relationship of θ1 <θ2 may be valid for the entire circumference of each frame or may be partially valid. Moreover, each frame may be comprised by one ring-shaped component, and may be comprised by the combination of several components. Furthermore, irregularities, steps, holes, and the like may be provided on the surface of the frame.

  As described above, according to the preforming apparatuses 60, 150, 200, 250, 300, and 350 according to the embodiments, before the main forming of the main forming apparatus 62, the pre-bending is performed using the support frame dedicated to the pre-forming. Since the molding is performed, it is possible to realize the production of the glass plate G having a high optical quality and a complicated shape and a deep bent shape, which has been difficult to produce by the conventional technology, with high production efficiency. Further, it is obvious that the present invention is applicable not only to the molding of window glass for automobiles but also to the molding of window glasses for other vehicles, aircraft, ships, buildings, and the like.

  In the present embodiment, a plurality of air holes 74 are formed in the molding surfaces 73 and 89 of the preforming mold 72 and the main-molding mold 88, and the glass plate G is pressed by preforming and main-molding. Since the glass plate G is sucked from the air holes 74 of the molding mold 72 and the main molding mold 88 and the glass plate G is pressed against the molding surfaces 73 and 89 of the preforming mold 72 and the preforming mold 88, The molding accuracy in preforming or main molding is improved.

The perspective view which showed through a part of bending apparatus of the glass plate which concerns on 1st Embodiment, and showed it Side view schematically showing the structure of the bending apparatus shown in FIG. Plan view showing the structure of the positioner moving device The side view which shows the structure of the moving apparatus shown in FIG. Sectional drawing which showed the principal part structure of the bending apparatus of the glass plate shown in FIG. Sectional drawing which showed the structure of the preforming apparatus shown in FIG. Sectional drawing which showed the principal part structure of the bending forming apparatus of the glass plate of 2nd Embodiment Sectional drawing which showed the structure of the preforming apparatus shown in FIG. Sectional drawing which showed the principal part structure of the bending forming apparatus of the glass plate of 3rd Embodiment Sectional drawing which showed the principal part structure of the bending forming apparatus of the glass plate of 4th Embodiment Sectional drawing which showed the principal part structure of the bending forming apparatus of the glass plate of 5th Embodiment Sectional drawing which showed the principal part structure of the bending forming apparatus of the glass plate of 6th Embodiment (A)-(d) is explanatory drawing which shows arrangement | positioning of a preforming means and this shaping | molding means (A)-(c) is explanatory drawing which shows the other form of the means to transfer the heat-softened glass plate to the support frame for preforming The top view which shows other embodiment of a positioner (A) is a side view showing a preforming support frame, (b) is a side view showing a main forming support frame, and (c) is a preforming support frame (or main forming support frame) and a glass plate. Plan view showing an example of the positional relationship of

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Bending molding apparatus, 11 ... Controller, 12 ... Heating furnace, 14 ... Positioning zone, 16 ... Molding furnace, 18 ... Air cooling strengthening zone, 20 ... Roller conveyor for carrying out, 28 ... Roller conveyor, 30 ... Hearth bed, 32 ... Traveling positioner, 35 ... Flat mold, 60, 150, 200, 250, 300, 350 ... Pre-forming device, 62 ... Main forming device, 64, 254 ... Pre-forming support frame, 72 ... Pre-forming mold, 84 ... Support frame for main molding, 88 ... Mold for main molding, 152 ... Female mold, 202 ... Local heater, 252 ... Ring component

Claims (10)

In a glass plate bending method comprising a heating step of heat-softening a glass plate and a bending step of bending the heat-softened glass plate into a predetermined shape,
The bending process includes
The heat-softened glass plate is placed on a preforming support frame that supports the edge thereof, and the glass plate is molded into a predetermined pre-bending shape while being placed on the preforming support frame. Molding process;
The glass plate molded in this pre-bending shape is transferred to a main molding support frame that supports the edge of the glass plate, and the glass plate is molded into the main molding mold in a state of being placed on the main molding support frame. And a main forming step of forming the glass sheet into a final bent shape by pressing against a surface.   2. The glass plate bending according to claim 1, wherein a deformation amount of the glass plate generated in the preforming step is 20 to 80% of a deformation amount of the glass plate generated between the heating step and the main forming step. Molding method.   The glass sheet bending method according to claim 1 or 2, wherein the preliminary forming step and the main forming step are performed in a heating furnace.   The step of forming into the pre-bending shape is (a) a step of pressing the glass plate between the preforming support frame and a preforming mold, and (b) placed on the preforming support frame. Sucking the lower surface of the glass plate, (c) heating at least a part of the glass plate placed on the preforming support frame, and (d) placed on the preforming support frame. The bending of the glass plate according to any one of claims 1 to 3, which is at least one selected from the step of supporting a part of the glass plate with a ring component that can be raised and lowered, or a combination of two or more. Molding method. In a glass plate bending apparatus comprising heating means for heat-softening a glass plate and bending means for bending the heat-softened glass plate into a predetermined shape,
The bending means is
A pre-forming support frame on which the heat-softened glass plate is placed and supporting the edge thereof, and a means for forming the glass plate placed on the pre-forming support frame into a predetermined pre-bending shape. Preforming means;
The glass plate formed in this pre-bending shape is mounted and has a main forming support frame for supporting the edge portion thereof, and a main forming mold for pressing the glass plate, and the glass plate is finally bent. A glass plate bending apparatus comprising: a main forming means for forming a glass sheet.   The glass plate bending apparatus according to claim 5, wherein a deformation amount of the glass plate generated by the preforming means is 20 to 80% of a deformation amount finally generated in the glass plate.   The means for forming the preformed shape includes: (a) a preforming mold for pressing the glass plate; (b) a suction chamber disposed below the preforming support frame; and communicating with the suction chamber. Means for air suction, (c) means for heating at least a part of the glass plate placed on the preforming support frame, and (d) a plurality of rings constituting the preforming support frame The at least one selected from the structural member and the means provided with the drive means to move up and down at least any one of this ring structural member, or a combination of two or more. Glass plate bending equipment.   A plurality of holes are formed in the molding surface of the main molding mold and / or the preforming mold, and after pressing the glass plate, air is sucked through the plurality of holes to thereby form the glass plate. The glass sheet bending apparatus according to claim 5, wherein the apparatus is bent.   The glass sheet bending apparatus according to any one of claims 5 to 8, wherein the preforming means and the main forming means are installed in a heating furnace.   A roller conveyor for conveying the heat-softened glass plate, a floating means disposed on the most downstream side of the roller conveyor and floating on the glass plate conveyed by the roller conveyor by jet air, and the floating means The flat mold which holds the said glass plate made without contacting this glass plate, and the positioning means which adjusts the position with respect to the said flat mold of the said glass plate, It further provided in any one of Claims 5-9. The bending apparatus of the glass plate of description.

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