Molding system, molding method, and program

Abstract

To provide a molding system reducing influence due to tilting and decentering of a metal mold to enhance shape accuracy of a molded article: to provide a molding method: and to provide a program.SOLUTION: A molding system 100 includes: a load detection device 20 detecting load applied from a metal mold 1 with respect to press molding of a molding material 5 performed by moving a movable mold 2 toward a stationary die 3 of the metal mold 1; a stage 23 rotating a table 23a where the metal mold 1 is placed, around a first rotation center P1 in a first vertical face and rotating the table around a second rotation center P2 in a second vertical face orthogonal to the first vertical face; and an arithmetic device 30 controlling the stage 23 so that a tilting angle of a center shaft of the movable mold 2 with respect to the center shaft of the stationary die 3 on the basis of the position of the center of gravity of the load calculated on the basis of a detection result of the load detection device 20 is made smaller. The first rotation center P1 is superimposed on the metal mold 1 in the first vertical face, and the second rotation center P2 is superimposed on the metal mold 1 in the second vertical face.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a molding system, a molding method, and a program (computer program). [Background technology]

[0002] In recent years, aspherical shapes are often used in glass lenses in order to improve performance and reduce the number of lenses. In particular, lenses that use aspherical shapes have only one optical axis on the aspherical side, and if tilt occurs in the mold placed opposite during the glass molding process, the problem of not being able to obtain the desired optical performance becomes prominent. In recent years, there are cases where both sides are aspherical, and if tilt occurs, the performance of the single lens is reduced.

[0003] Thus, in a conventional glass lens molding apparatus in which glass softened by heating is press-molded using a mold, a three-axis load detection device is provided on the movable axis (or fixed axis) to detect the occurrence of tilt of the press axis (see, for example, Patent Document 1).

[0004] Specifically, in a conventional glass lens molding device, the machining resistances Fx and Fy are detected and calculated by a three-axis load detection device, and the calculated value is used as a feedback signal to drive the axis attitude control unit in a direction that eliminates the tilt that occurs on the molding surface of the mold. As a result, the occurrence of tilt between the upper and lower axes is prevented, and the parallelism between the upper and lower molds can be ensured. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2003-246630 A Summary of the Invention [Problem to be solved by the invention]

[0006] The glass molding apparatus disclosed in Patent Document 1 can prevent the occurrence of tilt, in which the central axes of the upper and lower molds are not parallel to each other and are inclined, but does not take into consideration the prevention of decentering, in which the central axes of the upper and lower molds do not coincide and are misaligned.

[0007] That is, in the configuration of a conventional glass lens molding apparatus, it is possible to eliminate tilt, which is an inclination error during glass molding, but axial misalignment (decentering) arises as a new issue.

[0008] The present disclosure provides a molding system, molding method, and program that can reduce the effects of mold tilt and decentering to improve the shape accuracy of molded products. [Means for solving the problem]

[0009] A molding system according to one embodiment of the present disclosure includes a load detection device that detects a load received from a mold in press molding of a molding material, which is performed by using a mold having fixed and movable molds that sandwich the molding material in the vertical direction and moving the movable mold relatively toward the fixed mold; a table on which the mold is placed; a first rotation mechanism that rotates the table about a first rotation center above the table in a first vertical plane; and a second rotation mechanism that rotates the table about a second rotation center above the table in a second vertical plane perpendicular to the first vertical plane, a stage in which the first rotation center overlaps with the mold in the first vertical plane and the second rotation center overlaps with the mold in the second vertical plane; and a computing device that executes a center of gravity position calculation process that calculates the center of gravity position of the load based on the detection result of the load detection device; and an adjustment process that controls the first rotation mechanism and the second rotation mechanism of the stage so that the tilt angle of the central axis of the movable mold relative to the central axis of the fixed mold is reduced based on the center of gravity position calculated in the center of gravity position calculation process.

[0010] A molding method according to an embodiment of the present disclosure is a molding method executed by a calculation device connected to a load detection device and a stage. The load detection device detects a load received from a die in press molding of a molding material, which is performed by using a die having a fixed die and a movable die that sandwich the molding material in the vertical direction and relatively moving the movable die toward the fixed die. The stage has a table on which the die is placed, a first rotation mechanism that rotates the table about a first rotation center above the table in a first vertical plane, and a second rotation mechanism that rotates the table about a second rotation center above the table in a second vertical plane perpendicular to the first vertical plane, so that the first rotation center overlaps with the die in the first vertical plane and the second rotation center overlaps with the die in the second vertical plane. The molding method includes a center-of-gravity position calculation process that calculates the center-of-gravity position of the load based on the detection result of the load detection device, and an adjustment process that controls the first rotation mechanism and the second rotation mechanism of the stage so that the tilt angle of the central axis of the movable die relative to the central axis of the fixed die is reduced based on the center-of-gravity position calculated by the center-of-gravity position calculation process.

[0011] A program according to one aspect of the present disclosure is a program for causing a computing device to execute the above molding method. Effect of the Invention

[0012] According to an aspect of the present disclosure, the effects of mold tilt and decentering can be reduced, thereby improving the shape accuracy of the molded product. [Brief description of the drawings]

[0013] [Figure 1] 1 is a schematic diagram of a configuration example of a molding system according to a first embodiment; [Diagram 2] Cross-sectional view showing an example of die tilt [Diagram 3] FIG. 11 is a cross-sectional view showing an example of a state after press molding is performed with tilt occurring. [Figure 4] Enlarged view of part E in Figure 2. [Diagram 5] A cross-sectional view showing an example of a decentered mold. [Figure 6]FIG. 2 is an explanatory diagram of a configuration example of a load detection device of the molding system of FIG. [Figure 7] FIG. 2 is a block diagram of a configuration example of a calculation device of the molding system of FIG. [Figure 8] A graph showing the movement of the center of gravity of the load applied from the die [Figure 9] Graph showing an example of the relationship between the shift amount of the center of gravity of a load and the tilt angle [Figure 10] 2 is a flowchart of a first example of a manufacturing method using the molding system of FIG. 1. [Figure 11] 2 is a flowchart of a second example of a manufacturing method using the molding system of FIG. 1. [Figure 12] Schematic diagram of a configuration example of a molding system according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] [1. Embodiment] [1.1 First embodiment] [1.1.1 Overview] FIG. 1 is a schematic diagram of a configuration example of a molding system 100 according to a first embodiment. The molding system 100 in FIG. 1 manufactures a molded product of a molding material 5 by press-molding the molding material 5 using a mold 1. The molding material 5 is, for example, a glass material. The molded product is, for example, a lens. The glass material is processed into a predetermined shape in advance to obtain a desired shape of a lens. The predetermined shape is, for example, an ellipsoid or a sphere. In this embodiment, the molding material 5 is a spherical glass material. In this embodiment, the molding system 100 is a glass molding system, in particular, a glass lens molding system that mass-produces glass products such as lenses, which are representative optical elements, by molding techniques using molds.

[0015] The molding system 100 of FIG. 1 includes a load detection device 20, a stage 23, and a calculation device 30. The load detection device 20 detects a load received from a die 1 in relation to press molding of a molding material 5. The press molding of the molding material 5 is performed by using a die 1 having a movable die 2 and a fixed die 3 that sandwich the molding material 5, and relatively moving the movable die 2 toward the fixed die 3. The stage 23 includes a table 23a on which the die 1 is placed, a first rotation mechanism 23b that rotates the table 23a about a first rotation center P1 above the table 23a in a first vertical plane, and a second rotation mechanism 23c that rotates the table 23a about a second rotation center P2 above the table 23a in a second vertical plane perpendicular to the first vertical plane. In the first vertical plane, the first rotation center P1 overlaps with the die 1, and in the second vertical plane, the second rotation center P2 overlaps with the die 1. The calculation device 30 executes a center of gravity position calculation process that calculates the center of gravity position G (see Figure 6) of the load based on the detection result of the load detection device 20, and an adjustment process that controls the first rotation mechanism 23b and the second rotation mechanism 23c of the stage 23 so as to reduce the tilt angle α (see Figure 2) of the central axis C2 (see Figure 2) of the movable mold 2 relative to the central axis C3 (see Figure 2) of the fixed mold 3 based on the center of gravity position G calculated in the center of gravity position calculation process.

[0016] In this way, the molding system 100 can rotate the table 23a on which the mold 1 is placed about a first rotation center P1 above the table 23a in the first vertical plane and about a second rotation center P2 above the table 23a in the second vertical plane perpendicular to the first vertical plane. This allows the position of the mold 1 to be adjusted so that the tilt angle α of the central axis C2 of the movable mold 2 relative to the central axis C3 of the fixed mold 3 becomes small, thereby reducing the influence of the tilt of the mold 1. When the central axis C2 of the movable mold 2 is inclined relative to the central axis C3 of the fixed mold 3, the intersection point CP1 (see FIG. 2) between the central axis C3 of the fixed mold 3 and the central axis C2 of the movable mold 2 overlaps with the mold 1. The stage 23 is set so that the first rotation center P1 overlaps with the mold 1 in the first vertical plane and the second rotation center P2 overlaps with the mold 1 in the second vertical plane (see FIG. 1). That is, the first rotation mechanism 23b and the second rotation mechanism 23c of the stage 23 can adjust the inclination of the central axis C2 of the movable mold 2 with respect to the central axis C3 of the fixed mold 3, centered on a position close to the intersection CP1 of the central axis C3 of the fixed mold 3 and the central axis C2 of the movable mold 2 when tilt occurs. Therefore, when the position of the mold 1 is adjusted so that the tilt angle α of the central axis C2 of the movable mold 2 with respect to the central axis C3 of the fixed mold 3 becomes small, the increase in the distance between the central axis C3 of the fixed mold 3 and the central axis C2 of the movable mold 2 is reduced, and the effect of decentering of the mold 1 can be reduced. In this way, according to the molding system 100, the effect of tilt and decentering of the mold 1 can be reduced, thereby improving the shape accuracy of the molded product.

[0017] [1.1.2 Details] Hereinafter, a detailed description will be given of the molding system 100 of this embodiment. The molding system 100 is used to manufacture a molded product by press molding of a molding material 5 using a die 1. The molded product is, for example, a lens.

[0018] In this embodiment, the molding material 5 is a glass material. In this case, a molded product manufactured by press molding the molding material 5 is, for example, a glass lens. The mold 1 enables the manufacture of a glass lens by press molding the glass material. As shown in FIG. 1, the mold 1 has a movable mold 2 and a fixed mold 3 that sandwich the molding material 5 in the vertical direction (up-down direction). The movable mold 2 is an upper mold (upper punch). The fixed mold 3 is a lower mold (lower punch). The molding material 5 is sandwiched between the movable mold 2 and the fixed mold 3. The movable mold 2 and the fixed mold 3 are arranged so as to face each other in the up-down direction (vertical direction). The mold 1 further has a sleeve 4. The sleeve 4 is a body mold that holds the movable mold 2 and the fixed mold 3 that face each other. For example, the movable mold 2 and the fixed mold 3 are columnar, and the sleeve 4 is cylindrical in shape and capable of housing the movable mold 2 and the fixed mold 3 inside. The movable mold 2 is movable along the central axis of the sleeve 4 relative to the fixed mold 3 within the sleeve 4. The shapes of the opposing surfaces of the movable die 2 and the fixed die 3 are set according to the desired shape of the molded product. The work of assembling the mold 1, that is, the work of placing the molding material 5 between the movable die 2 and the fixed die 3 and housing them in the sleeve 4, may be performed manually or may be automated by a machine. By automating the process by machine, productivity can be increased.

[0019] 1 includes a heating mechanism 7 and a driving mechanism 9. The heating mechanism 7 heats the molding material 5. The driving mechanism 9 moves the movable die 2 relatively toward the fixed die 3 of the mold 1.

[0020] The heating mechanism 7 in FIG. 1 is configured to include a first heater block 7a and a second heater block 7b. Each of the first heater block 7a and the second heater block 7b has a plurality of rod-shaped heaters 6. The first heater block 7a is formed, for example, in a plate shape so as to come into surface contact with the movable die 2 of the mold 1. The first heater block 7a heats the molding material 5 by heating the movable die 2 of the mold 1. The first heater block 7a is disposed so as to face the second heater block 7b in the vertical direction. The first heater block 7a is connected to the drive mechanism 9 via a first insulating material 8a and can be moved in the vertical direction by the drive mechanism 9. The second heater block 7b is formed, for example, in a plate shape so as to come into surface contact with the fixed die 3 of the mold 1. The second heater block 7b heats the molding material 5 by heating the fixed die 3 of the mold 1. The second heater block 7b is supported by the stage 23 via a second insulating material 8b.

[0021] The drive mechanism 9 in FIG. 1 includes a pressure source 9a and a press shaft (pressurizing shaft) 9b. The pressure source 9a is, for example, an air cylinder. One end of the press shaft 9b is connected to the pressure source 9a, and the other end of the press shaft 9b is connected to the first heater block 7a via the first insulating material 8a. The drive mechanism 9 moves the press shaft 9b using the pressure source 9a, thereby moving the first heater block 7a toward the second heater block 7b, and thereby moving the movable die 2 toward the fixed die 3.

[0022] In press molding by the molding system 100 in Fig. 1, the molding material 5 arranged between the movable die 2 and the fixed die 3 of the die 1 is heated and melted by the heating mechanism 7, and then the movable die 2 is moved toward the fixed die 3 of the die 1 by the driving mechanism 9, thereby transferring the shape of the die 1 to the molding material 5. In this way, the molding system 100 is capable of producing a molded product from the molding material 5 by press molding. The molding system 100 has one press shaft 9b for press molding. The molding system 100 is a so-called single-shaft molding machine.

[0023] During press molding, the die 1 may tilt. FIG. 2 is a cross-sectional view showing an example of the tilt of the die 1. In the present disclosure, the tilt of the die 1 refers to the movable die 2 being tilted relative to the fixed die 3. The movable die 2 being tilted relative to the fixed die 3 refers to the central axis C2 of the movable die 2 being tilted relative to the central axis C3 of the fixed die 3 without the central axis C2 of the movable die 2 and the central axis C3 of the fixed die 3 being parallel to each other. In the present disclosure, the angle between the central axis C2 of the movable die 2 and the central axis C3 of the fixed die 3 is called the tilt angle α. Such a tilt of the die 1 occurs, for example, when the first heater block 7a is tilted relative to the second heater block 7b. When the die 1 tilts, the intersection CP1 between the central axis C3 of the fixed die 3 and the central axis C2 of the movable die 2 usually overlaps with the die 1.

[0024] As shown in FIG. 2, when press molding is performed with the die 1 tilted, asymmetric deformation occurs in the molding material 5. FIG. 3 is a cross-sectional view showing an example of a state after press molding is performed with the die 1 tilted. The molding material 5 in FIG. 3 is not symmetrical with respect to the center, but has an asymmetric shape in which the distance d1 from the center to one end (the left end in FIG. 3) is different from the distance d2 from the center to the other end (the right end in FIG. 3). In addition, the center of the molding material 5 is shifted by Δd from the central axis C3 of the fixed die 3. If the molding material 5 is a lens, the actual optical axis of the lens is tilted with respect to the desired optical axis, and the performance of the lens is reduced.

[0025] The reason why such asymmetric deformation occurs is that the molding material 5 is not pressed straight against the fixed mold 3 by the movable mold 2, but a horizontal component force is generated. FIG. 4 is an enlarged view of the part indicated by E in FIG. 2. As shown in FIG. 4, when the mold 1 is tilted, the movable mold 2 contacts the molding material 5 at a point P22 shifted from the point P21, not at the point P21 when the central axis C2 of the movable mold 2 and the central axis C3 of the fixed mold 3 coincide. In the case of the point P21, the movable mold 2 applies a load in the direction of the central axis C3 of the fixed mold 3. On the other hand, in the case of the point P22, the movable mold 2 applies a load F1 in a direction inclined with respect to the central axis C3 of the fixed mold 3. The load F1 includes a component F11 in the direction of the central axis C3 of the fixed mold 3 and a component F12 (horizontal component force) perpendicular to the direction of the central axis C3 of the fixed mold 3. The component F12 presses the molding material 5 in a direction perpendicular to the direction of press molding by the mold 1, resulting in asymmetric deformation.

[0026] As described above, if press molding is performed with a tilt in die 1 as shown in FIG. 2, a lens with a tilt in its optical axis will be manufactured. Such a lens is unlikely to satisfy the desired performance, and is one of the causes of reduced yields.

[0027] In press molding, decentering may occur in the mold 1 in addition to tilt. FIG. 5 is a cross-sectional view showing an example of decentering of the mold 1. In this embodiment, decentering of the mold 1 refers to the relative displacement of the movable mold 2 with respect to the fixed mold 3. The relative displacement of the movable mold 2 with respect to the fixed mold 3 refers to the fact that the central axis C2 of the movable mold 2 is not tilted with respect to the central axis C3 of the fixed mold 3, but the central axis C2 of the movable mold 2 and the central axis C3 of the fixed mold 3 do not coincide with each other. In this embodiment, the distance between the central axis C2 of the movable mold 2 and the central axis C3 of the fixed mold 3 is called the axial displacement Δh. Such decentering of the mold 1 occurs, for example, when the movable mold 2 is displaced with respect to the fixed mold 3. If press molding is performed with decentering of the mold 1 as shown in FIG. 5, for example, the position of the optical axis (center position) is displaced between both sides of the molding material 5 (the upper and lower surfaces in FIG. 5). In particular, when the molded product to be obtained from the molding material 5 is an optical lens having an aspherical shape, the transmission decentering may become large, and the performance as a single lens may be deteriorated.

[0028] Decentering of the mold 1 may occur when eliminating the tilt of the mold 1. For example, the glass molding device disclosed in the above-mentioned Patent Document 1 can prevent the occurrence of tilt, in which the central axes of the upper and lower molds are not parallel to each other and are inclined, but does not take into consideration the prevention of decentering, in which the central axes of the upper and lower molds are not aligned and are misaligned.

[0029] The molding system 100 in FIG. 1 includes a load detection device 20, a stage 23, a calculation device 30, and a control device 34 in order to reduce the effects of tilt and decentering of the mold 1 and to improve the shape accuracy of the molded product.

[0030] The load detection device 20 detects the load received from the die 1 in the press molding of the molding material 5, which is performed by relatively moving the movable die 2 toward the fixed die 3 using the die 1. The load detection device 20 in FIG. 1 includes a plurality of load sensors 21 and an amplifier 22 that amplifies the output from the plurality of load sensors 21 and outputs the output to the calculation device 30. In the load detection device 20, the plurality of load sensors 21 are disposed between the die 1 and the stage 23. More specifically, the load sensor 21 is disposed between the second insulating material 8b and the stage 23, and receives a load from the die 1. In the load detection device 20, the plurality of load sensors 21 detect the load from the die 1 at the corresponding positions and output a detection signal indicating the load from the die 1, and the detection signals from the plurality of load sensors 21 are amplified by the amplifier 22 and output to the calculation device 30.

[0031] FIG. 6 is an explanatory diagram of a configuration example of the load detection device 20. In particular, FIG. 6 is an explanatory diagram of an example of the arrangement (planar arrangement) of the multiple load sensors 21 (21-1 to 21-4) of the load detection device 20. In FIG. 6, the X-axis and the Y-axis are horizontal axes, and the Z-axis is a vertical axis. The pressing direction during press molding is the direction of the Z-axis. The XY plane defined by the X-axis and the Y-axis is an action plane F on which the load detection device 20 receives a load from the die 1. The action plane F is used as a virtual plane for deriving the center of gravity position G of the load. The action plane F is usually perpendicular to the central axis C3 of the fixed die 3. In FIG. 6, the origin of the XY coordinates is set to coincide with the center position O of the fixed die 3 of the die 1.

[0032] 6, each of the four load sensors 21-1, 21-2, 21-3, and 21-4 is a one-axis load sensor capable of detecting a load from the die 1 in the press direction (direction of the Z axis). The four load sensors 21-1, 21-2, 21-3, and 21-4 are arranged symmetrically (point-symmetrically) with respect to the origin of the XY coordinates, that is, the center position O. The load sensors 21-1, 21-2, 21-3, and 21-4 are arranged at positions ±m away from the X axis and ±n away from the Y axis within the action surface F. More specifically, in the XY coordinates, the coordinates of the load sensor 21-1 are (+n, -m), the coordinates of the load sensor 21-2 are (-n, -m), the coordinates of the load sensor 21-3 are (-n, +m), and the coordinates of the load sensor 21-4 are (+n, +m). In this way, the load sensor 21 is arranged symmetrically with respect to the origin of the XY coordinate system because the coordinates of the center of gravity (COP) G of the load (a x ,a y ) to facilitate the calculations required to derive

[0033] The load sensors 21-1 to 21-4 of the load detection device 20 detect loads z1, z2, z3, and z4 on the Z axis, respectively. The load on the action surface F1 on the Z axis, that is, the load Fz received from the die 1, is the sum of z1 to z4. The coordinates of the center position G of the load (a x ,a y ) for a x =M x / F z and a y =M y / F z It can be calculated by M x is the moment around the X-axis with the origin of the XY coordinate system as the center, and is expressed by the following equation (1). y is the moment around the Y axis centered on the origin of the XY coordinate system, and is expressed by the following equation (2).

[0034]

number

[0035] Therefore, the coordinates of the center of gravity G of the load (a x ,a y) can be calculated using the following equations (3) and (4).

[0036]

number

[0037] According to the load detection device 20, it is possible to calculate the center of gravity G of the load by the four load sensors 21. The loads z1, z2, z3, and z4 detected by the four load sensors 21 are not minute values ​​such as the horizontal component forces Fx and Fy described in Patent Document 1, and therefore each has sufficient detection sensitivity.

[0038] In the example configuration of the load detection device 20 shown in Figure 6, four load sensors 21 are arranged, but since the center of gravity position can be calculated with at least three load sensors 21, the load sensors 21 may be arranged in three locations that are not aligned in a straight line in a plane perpendicular to the central axis C3 of the fixed mold 3 (for example, in three of the four areas from the first quadrant to the fourth quadrant in the XY plane).

[0039] The stage 23 adjusts the position of the mold 1. In particular, the stage 23 is used to adjust the relative position of the fixed mold 3 with respect to the movable mold 2. The stage 23 in Fig. 1 is configured to include a table 23a, a first rotation mechanism 23b, and a second rotation mechanism 23c.

[0040] The table 23a is a portion of the stage 23 on which the mold 1 is placed.

[0041] The first rotation mechanism 23b rotates the table 23a about the first rotation center P1 in the first vertical plane. In FIG. 1, A1 and A2 indicate the central axis of the table 23a, where A1 is along the direction of the Z axis and A2 is inclined at an angle θ with respect to the direction of the Z axis. In this embodiment, the first rotation mechanism 23b supports the table 23a rotatably about the first rotation center P1 in the first vertical plane. The first vertical plane is, for example, the XZ plane. The first rotation center P1 is located above the table 23a. As shown in FIG. 1, the first rotation center P1 overlaps with the mold 1 in the first vertical plane. In particular, the first rotation center P1 is set so as to overlap with the molding material 5 disposed between the movable mold 2 and the fixed mold 3 of the mold 1 in the first vertical plane. Furthermore, the first rotation center P1 is closer to the center of the mold 1 than the outside of the mold 1 in the first vertical plane. The first rotation mechanism 23b includes a drive source such as a servo motor, and rotates the table 23a about a first rotation center P1 within a first vertical plane in response to a first control signal from the control device .

[0042] The second rotation mechanism 23c rotates the table 23a about the second rotation center P2 in the second vertical plane. More specifically, the second rotation mechanism 23c supports the table 23a and the first rotation mechanism 23b rotatably about the second rotation center P2 in the second vertical plane. The second vertical plane is perpendicular to the first vertical plane. The second vertical plane is, for example, a YZ plane. The second rotation center P2 is above the table 23a. The second rotation center P2 overlaps with the mold 1 in the second vertical plane. In particular, the second rotation center P2 is set to overlap with the molding material 5 disposed between the movable mold 2 and the fixed mold 3 of the mold 1 in the second vertical plane. Furthermore, the second rotation center P2 is closer to the center of the mold 1 than the outside of the mold 1 in the second vertical plane. The second rotation mechanism 23c includes a drive source such as a servo motor, and rotates the table 23a about the second rotation center P2 in the second vertical plane in response to a second control signal from the control device 34.

[0043] In this embodiment, the first rotation center P1 and the second rotation center P2 are at the same position. In the molding system 100 of Fig. 1, the second insulating material 8b adjusts the position of the mold 1 relative to the first rotation center P1 and the second rotation center P2. In other words, the second insulating material 8b is an adjustment member that is disposed between the table 23a and the mold 1 so that the mold 1 overlaps the first rotation center P1 in the first vertical plane and overlaps the second rotation center P2 in the second vertical plane.

[0044] The stage 23 described above is a stack of the first rotation mechanism 23b, which is the first swivel stage that rotates in the XZ plane, and the second rotation mechanism 23c, which is the second swivel stage that rotates in the YZ plane. The stacked first and second swivel stages operate in pairs to form a two-axis swivel stage. An example of a two-axis swivel stage is SA16A-RS01 manufactured by Kohzu Seiki Co., Ltd. In the two-axis swivel stage, the rotation center of the first swivel stage that rotates in the XZ plane (i.e., the first rotation center P1 of the first rotation mechanism 23b) and the rotation center of the second swivel stage that rotates in the YZ plane (i.e., the second rotation center P2 of the second rotation mechanism 23c) can be set to the same position (point). For example, the first rotation center P1 and the second rotation center P2 of the stage 23 may be set near the center of the mold 1. This is because, as explained in FIG. 2, the tilt that occurs within the mold 1 has a rotation center near the center of the mold 1 (the intersection CP1 of the central axis C2 of the movable mold 2 and the central axis C3 of the fixed mold 3).

[0045] For example, if the mold 1 is compatible with molding a lens with an outer diameter of about 30 mm, an error of about ±10 mm between the center of the mold 1 and the rotation center of the two-axis swivel stage (first rotation center P1 and second rotation center P2) will not result in a large correction error. However, the allowable range of error varies depending on the shape and size of the lens. Since the size of the mold 1 changes depending on the type of lens, it is sufficient to appropriately set the center of the mold 1 within the allowable range of error, even if the center of the mold 1 and the rotation center of the two-axis swivel stage do not strictly coincide with each other.

[0046] The molding system 100 in FIG. 1, which will be described in detail later, corrects the tilt of the mold 1 by adjusting the angle of the table 23a in the first vertical plane and the second vertical plane by the first rotation mechanism 23b and the second rotation mechanism 23c constituting a two-axis swivel stage. The rotation center (intersection CP1 of the central axis C2 of the movable mold 2 and the central axis C3 of the fixed mold 3) of the tilt (angle error) of the mold 1 in FIG. 2 is near the center of the mold 1, and the first rotation center P1 and the second rotation center P2 of the stage 23 are also set near the center of the mold 1. This makes it possible to minimize the occurrence of decentering due to the difference in the positions of the rotation center of the tilt of the mold 1 and the first rotation center P1 and the second rotation center P2 of the stage 23 when correcting the tilt of the mold 1. As a result, the molding system 100 can mold a lens with small transmission eccentricity, that is, a lens with high accuracy.

[0047] The calculation device 30 has a function of executing a center of gravity position calculation process and a correction process. Fig. 7 is a block diagram of an example of the configuration of the calculation device 30. The calculation device 30 includes a processing device 31, a storage device 32, and a display device 33.

[0048] The storage device 32 is used to store information used by the processing device 31 and information generated by the processing device 31. The storage device 32 includes one or more storages (non-transient storage media). The storage may be, for example, any of a ROM, an EEPROM, a RAM, a USB memory, a magnetic disk, an optical disk, a magneto-optical disk, a hard disk drive, and a solid-state drive (SSD). The storage may be any of an internal type, an external type, and a NAS (network-attached storage) type. The information D30 stored in the storage device 32 includes, for example, a tilt conversion unit D31 used by the processing device 31 and a program D32 executed by the processing device 31.

[0049] The display device 33 is used, for example, to display information to a user. The display device 33 is, for example, a display.

[0050] The processing device 31 is connected to the load detection device 20 and the control device 34, and can access the storage device 32. The processing device 31 can be realized, for example, by a computer system including one or more processors (microprocessors) and one or more memories. The one or more processors execute a program D32 (stored in one or more memories or the storage device 32), thereby realizing the functions of the processing device 31. The program D32 is pre-recorded in the storage device 32 here, but may be provided via a telecommunications line such as the Internet, or recorded on a non-transitory recording medium such as a memory card.

[0051] The processor 31 executes a center-of-gravity position calculation process and an adjustment process. The center-of-gravity position calculation process and the adjustment process are realized by the processor 31 executing a program D32.

[0052] The center of gravity position calculation process calculates the center of gravity G of the load received from the mold 1 based on the detection result of the load detection device 20. The center of gravity G of the load is expressed as the coordinates (a x ,a y ) is given by a x can be calculated by the above formula (3), and a y can be calculated using the above formula (4).

[0053] The adjustment process controls the first rotation mechanism 23b and the second rotation mechanism 23c of the stage 23 so as to reduce the tilt angle α of the central axis C2 of the movable mold 2 relative to the central axis C3 of the fixed mold 3 based on the center of gravity position G calculated in the center of gravity position calculation process. More specifically, the adjustment process controls the first rotation mechanism 23b and the second rotation mechanism 23c of the stage 23 by outputting a control command to the control device 34 so as to reduce the tilt angle α of the central axis C2 of the movable mold 2 relative to the central axis C3 of the fixed mold 3 based on the center of gravity position G calculated in the center of gravity position calculation process.

[0054] When the molding material 5 is deformed symmetrically, the coordinates of the center of gravity G (a x ,a y) is considered to coincide with the coordinates (0,0) of the center position O, which is the origin of the action surface F, or to be within the allowable range of the center position O, when the press forming is completed. On the other hand, when the forming material 5 is deformed asymmetrically, the coordinates (a x ,a y ) is considered to be significantly displaced from the coordinate (0,0) of the center of gravity O at the end of press forming. x ,a y If the coordinates (a) of the center position G are within the allowable range, it is considered that symmetric deformation has occurred in the molding material 5. x ,a y ) changes significantly and falls outside the allowable range, it is considered that asymmetric deformation has occurred in the molding material 5.

[0055] FIG. 8 shows the movement of the center of gravity G of the load received from the die 1, that is, the coordinates of the center of gravity G (a x ,a y ) is a graph showing the locus of the center of gravity G. Before press molding, the molding material 5 is placed at the center of the fixed die 3. Therefore, at the start of press molding, the coordinates (a x ,a y ) coincides with the coordinates (0,0) of the center position O, that is, the origin of the XY plane. When the die 1 is tilted, a horizontal component force is generated as described above. Therefore, as the press forming progresses, the coordinates (a x ,a y ) moves away from the coordinates (0,0) of the center position O to the position shown in FIG. 8. The amount of movement d of the center of gravity position G due to press molding is calculated by the coordinates (a x ,a y The movement direction γ of the center of gravity G is the angle of the line connecting the center of gravity G at the start of press forming and the center of gravity G at the end of press forming, and is given by the following equation (5) using the coordinates (a x ,a y ) is given by the following equation (6).

[0056]

number

[0057] The amount of movement d corresponds to a tilt angle α, which is the amount by which the central axis C2 of the movable mold 2 is tilted relative to the central axis C3 of the fixed mold 3. The direction of movement γ corresponds to the direction in which the central axis C2 of the movable mold 2 is tilted relative to the central axis C3 of the fixed mold 3.

[0058] As described above, the first rotation mechanism 23b and the second rotation mechanism 23c of the stage 23 are controlled so that the tilt angle α becomes smaller. To achieve this, the adjustment process converts the movement amount d into the tilt angle α. FIG. 9 is a graph showing an example of the relationship between the movement amount d of the center of gravity position G of the load and the tilt angle α. In this embodiment, the relationship between the movement amount d and the tilt angle α is obtained in advance. For example, the tilt conversion unit D31 stored in the storage device 32 indicates the correspondence relationship between the movement amount d and the tilt angle α.

[0059] An example of a method for determining in advance the relationship between the shift amount d of the center of gravity G of the load and the tilt angle α as shown in FIG. 9 will be described. First, the molding system 100 actually performs press molding of the molding material 5 to obtain a glass lens as a molded product. In this case, the first rotation mechanism 23b and the second rotation mechanism 23c are set to their initial positions on the stage 23. The initial position of the first rotation mechanism 23b is a position where the central axis of the table 23a is aligned with the direction of the Z axis in the first vertical plane. The initial position of the second rotation mechanism 23c is a position where the normal direction of the table 23a is aligned with the direction of the Z axis in the second vertical plane. After performing press molding under these conditions, the eccentricity accuracy of the obtained glass lens is measured using an eccentricity microscope or the like. At this time, the eccentricity amount and the eccentricity direction of the obtained glass lens are measured. The glass lens obtained in this way is used as a reference. Ideally, the eccentricity error in the eccentricity microscope is as close to zero degrees as possible, and the shift amount d of the center of gravity G of the load is also zero.

[0060] Next, only one of the first rotation mechanism 23b and the second rotation mechanism 23c of the stage 23 is operated, and an angle of, for example, 1 minute is applied, and press molding is performed in the same manner. After that, the obtained glass lens is measured with an eccentricity microscope. Ideally, an eccentricity error corresponding to a tilt angle α of 1 minute occurs in the glass lens, and the movement amount d of the center of gravity position G of the load also becomes a value corresponding to a tilt angle α of 1 minute. After that, the angle is increased to 2 minutes, 3 minutes, 4 minutes, etc., and press molding is performed each time, and the movement amount d of the center of gravity position G of the load is obtained for the obtained glass lens. As a result, a graph as shown in FIG. 9 is obtained. Note that the relationship between the movement amount d and the tilt angle α as shown in the graph of FIG. 9 varies depending on the material and shape of the molding material 5 and the mold 1, and the type of molded product such as a glass lens, but can be easily obtained by the above-mentioned procedure.

[0061] The tilt conversion unit D31 stored in the storage device 32 indicates the relationship between the tilt angle α and the amount of movement d. Therefore, it is possible to easily obtain the tilt angle α from the amount of movement d calculated using the detection result of the load detection device 20. For that reason, the adjustment process converts the amount of movement d into the tilt angle α and outputs an adjustment instruction to the control device 34.

[0062] As described above, the movement direction γ corresponds to the tilt direction of the central axis C2 of the movable mold 2 relative to the central axis C3 of the fixed mold 3. The ratio of the angles of the first rotation mechanism 23b and the second rotation mechanism 23c of the stage 23 is set according to the movement direction γ. For example, in FIG. 8, when the movement direction γ is 90 degrees or 270 degrees, the tilt angle α is an angle in the YZ plane, so that it is sufficient to rotate the table 23a by operating only the second rotation mechanism 23c. For example, in FIG. 8, when the movement direction γ is 45 degrees, it is sufficient to rotate the table 23a by the same angle using the first rotation mechanism 23b and the second rotation mechanism 23c.

[0063] In this way, the adjustment process can output adjustment instructions to the control device 34 indicating target values ​​for the angles of the first rotation mechanism 23b and the second rotation mechanism 23c, based on the movement amount d and movement direction γ calculated on the basis of the detection results of the load detection device 20, so that movement of the center of gravity position G of the load does not occur during press molding.

[0064] The processing device 31 determines whether to execute the adjustment process based on the detection result of the load detection device 20. This is because when the tilt angle α is small, the influence of the tilt angle α may be negligible. For example, the processing device 31 may execute the adjustment process when the tilt angle α exceeds a predetermined angle threshold. The predetermined angle threshold is appropriately set depending on whether asymmetric deformation occurs in the molding material 5. In addition, the relationship between the movement amount d and the tilt angle α indicates the movement amount d corresponding to the tilt angle α at which the influence on the molded product can be ignored. Therefore, the determination of whether to execute the adjustment process may be performed based on the movement amount d at which the influence on the molded product can be ignored. For example, the processing device 31 may execute the adjustment process when the center of gravity position G of the load is not within an allowable range of a predetermined distance threshold from the central axis C3 of the fixed mold 3 (the central position O corresponding to the origin of the action surface F). The predetermined distance threshold is appropriately set depending on whether asymmetric deformation occurs in the molding material 5.

[0065] The control device 34 controls the stage 23. The control device 34 outputs a first control signal and a second control signal to the first rotation mechanism 23b and the second rotation mechanism 23c of the stage 23, respectively, in accordance with an adjustment instruction from the calculation device 30. The first control signal indicates a target value for the angle of the first rotation mechanism 23b, and the second control signal indicates a target value for the angle of the second rotation mechanism 23c.

[0066] [1.1.3 Manufacturing method] [1.1.3.1 First Example] Next, a first example of a manufacturing method using the molding system 100 will be described with reference to Fig. 10. Fig. 10 is a flowchart of a first example of a manufacturing method using the molding system 100 of Fig. 1. The manufacturing method of Fig. 10 is suitable for mass production of lenses, and adjustment processing is performed as necessary for each lens produced. In other words, the manufacturing method of Fig. 10 is a method in which tilt correction is performed between lens production (press molding), and the correction is confirmed to be correct while proceeding.

[0067] 10, first, an initial setting is performed (S11). In the initial setting, the angle of the first rotation mechanism 23b and the angle of the second rotation mechanism 23c of the stage 23 are set to initial values ​​(for example, 0°).

[0068] Next, press molding of the lens is performed by the molding system 100 (S12). In the molding system 100 of Fig. 1, the press molding process includes a throwing step, a heating step, a molding step, a first cooling step, a second cooling step, and a removal step.

[0069] In the casting process, the movable die 2 is removed from the metal mold 1, and the molding material 5 is placed on the fixed die 3. Thereafter, the movable die 2 is inserted into the sleeve 4, and the molding material 5 is sandwiched between the fixed die 3 and the movable die 2. After this, the metal mold 1 is placed in the center of the second heater block 7b.

[0070] In the heating process, the heating mechanism 7 raises the temperature of the molding material 5a, which is a glass material, to a temperature at which the molding material 5 can be softened and molded. In the heating process, the press shaft 9b of the drive mechanism 9 is lowered and the first heater block 7a hardly applies a load to the molding material 5, in order to heat the molding material 5, and the first heater block 7a approaches or contacts the movable die 2 of the mold 1. In particular, since the temperature of the mold 1 immediately after being placed on the second heater block 7b is lower than the set temperature of the heating mechanism 7, the drive mechanism 9 hardly applies a load in this heating process. The reason is that if a large load is applied when the temperature of the molding material 5, which is a glass material, is low, the molding material 5 may crack or the surfaces of the movable die 2 and the fixed die 3 may be scratched or dented. In the latter half of the heating process, the molding material 5 reaches a temperature at which it can be sufficiently thermally deformed.

[0071] In the molding process, as the press axis 9b of the drive mechanism 9 descends, a load is applied to the molding material 5 by the first heater block 7a, and the molding material 5 is thermally deformed, so that the shape of the mold is transferred to the molding material 5, thereby obtaining a molding material 5 with a changed shape.

[0072] In the first cooling step, a load is applied to the movable die 2 in the same manner as in the molding step. The load applied in the first cooling step is intended to hold the die 1 for transfer, and is therefore smaller than the load applied in the molding step. In addition, the set temperature of the heating mechanism 7 in the first cooling step is controlled to be lower than the set temperature of the heating mechanism 7 in the molding step. In the first cooling step, the temperature of the molding material 5 is lowered, causing the molding material 5 to shrink, and the transfer of the mold shapes of the movable die 2 and the fixed die 3 to the molding material 5 is completed.

[0073] In the second cooling step, the press shaft 9b of the drive mechanism 9 moves the first heater block 7a close to or into contact with the movable die 2, thereby cooling the die 1 and the molding material 5. The purpose of the second cooling step is to cool the molding material 5 so that it can be removed from the die 1 in the subsequent removal step. For this reason, the set temperature of the heating mechanism 7 in the second cooling step is controlled to be much lower than the set temperature of the heating mechanism 7 in the first cooling step.

[0074] In the removal step, the mold 1 is disassembled, and the molding material 5 is removed from the mold 1.

[0075] In this manner, the press molding of the molding material 5 is completed, and a molded product is obtained by the press molding.

[0076] After the press forming, in the calculation device 30, the processing device 31 executes a center of gravity position calculation process to obtain the coordinates of the center of gravity position G (a x ,a y ) is calculated (S13). In this center of gravity position calculation process, the center of gravity position G of the load is calculated based on the detection result of the load detection device 20 after execution of press forming. Then, the movement amount d and movement direction γ of the center of gravity position G are calculated (S14). In addition, the tilt angle α is calculated from the movement amount d using the relationship between the movement amount d and the tilt angle α shown in FIG. 9 (S15).

[0077] Next, it is determined whether the tilt angle α calculated in step S15 is equal to or smaller than a predetermined angle threshold (S16). If the tilt angle α exceeds the predetermined angle threshold (S16: NO), the processing device 31 executes an adjustment process (S17). As a result, the adjustment of the stage 23 is executed so that the tilt angle α becomes smaller.

[0078] If the tilt angle α is equal to or smaller than the predetermined angle threshold (S16: YES), or after the adjustment process (S17), the next press molding is performed (S18). In step S18, the molding material 5 is press molded in the same procedure as in step S12.

[0079] After step S18, it is determined whether or not to end production (S19). For example, if the number of produced lenses reaches a specified number, it is determined to end production (S19: YES). If the number of produced lenses does not reach the specified number, it is determined not to end production (S19: NO), and the process returns to step S13 to produce a new lens. As a result, after an adjustment process (S17) is performed as necessary, press molding is performed (S18), and the lens is produced.

[0080] [1.1.3.2 Second Example] Next, a second example of the manufacturing method using the molding system 100 will be described with reference to FIG. 11. FIG. 11 is a flow chart of the second example of the manufacturing method using the molding system 100 of FIG. 1. The second example of the manufacturing method shown in FIG. 11 is suitable for mass production of lenses, similar to the first example of the manufacturing method shown in FIG. 10. In the first example of the manufacturing method shown in FIG. 10, an adjustment process is performed as necessary every time one lens is produced, whereas in the second example of the manufacturing method shown in FIG. 11, an adjustment process is performed as necessary in real time during the molding of the lens. That is, in the second example of the manufacturing method shown in FIG. 11, the load detection device 20 constantly measures the load received from the mold 1, which is more beneficial than the first example of the manufacturing method shown in FIG. 10 in that the magnitude and direction of the tilt of the mold 1 can be constantly monitored. In the second example of the manufacturing method shown in FIG. 11, the tilt of the mold 1 can be corrected during the production (press molding) of the lens. As a result, the influence of tilt and decentering is very small from the first lens produced at the beginning. Therefore, the manufacturing method is superior in terms of yield to the first example shown in FIG. 10.

[0081] 11, first, an initial setting is performed (S21). In the initial setting, the angle of the first rotation mechanism 23b and the angle of the second rotation mechanism 23c of the stage 23 are set to initial values ​​(for example, 0°).

[0082] Next, the molding material 5 is placed in the center of the fixed mold 3 by hand or machine, and the sleeve 4 and movable mold 2 are placed on top to assemble the mold 1 (S22). In the assembled state of the mold 1, the molding material 5 is sandwiched between the movable mold 2 and the fixed mold 3, and the movable mold 2 and the fixed mold 3 are held by the sleeve 4. Thereafter, the mold 1 is placed between the first and second heater blocks 7a, 7b and heated, and a load is applied by the drive mechanism 9 so that the movable mold 2 moves toward the fixed mold 3, and press molding of the molding material 5 begins (S23).

[0083] During the execution of press molding, in the arithmetic device 30, the processing device 31 executes a center of gravity position calculation process to obtain the coordinates of the center of gravity position G (a x ,a y) is calculated (S24). In this center of gravity position calculation process, the center of gravity position G of the load is calculated based on the detection result of the load detection device 20 during execution of press forming.

[0084] Next, it is determined whether the center of gravity position G of the load calculated in step S24 is within a predetermined distance threshold tolerance range from the central axis C3 of the fixed mold 3 (the central position O corresponding to the origin of the acting surface F) (S25). If the center of gravity position G of the load is not within the tolerance range (S25: NO), the processing device 31 executes an adjustment process (S26). In executing the adjustment process, the processing device 31 calculates the movement amount d and movement direction γ of the center of gravity position G, and calculates the tilt angle α from the movement amount d using the relationship between the movement amount d of the tilt conversion unit D31 and the tilt angle α. Through the adjustment process, the stage 23 is adjusted so that the tilt angle α becomes smaller.

[0085] If the center of gravity position G of the weight is within the allowable range (S25: YES), or after the adjustment process (S26), it is determined whether the press molding is completed (S27). If it is determined that the press molding is not completed (S27: NO), the process returns to step S24, and the processing device 31 executes the center of gravity position calculation process again to obtain the coordinates of the center of gravity position G (a x ,a y The center of gravity position G is repeatedly detected until the press forming is completed, and adjustment processing is performed as necessary, thereby correcting the tilt in real time.

[0086] If it is determined that the press molding is completed (S27: YES), it is determined whether or not to end the production (S28). For example, if the number of lenses produced reaches a specified number, it is determined that the production is to be ended (S28: YES). If the number of lenses produced does not reach the specified number, it is determined that the production is not to be ended (S28: NO), and the process returns to step S22 to produce a new lens. This starts the press molding (S23), and the lens is produced.

[0087] [1.1.4 Effects, etc.] The molding system 100 described above includes a mold 1 having a fixed mold 3 and a movable mold 2 that sandwich the molding material 5 in the vertical direction, and a load detection device 20 that detects a load received from the mold 1 in press molding of the molding material 5, which is performed by relatively moving the movable mold 2 toward the fixed mold 3, a table 23a on which the mold 1 is placed, a first rotation mechanism 23b that rotates the table 23a about a first rotation center P1 above the table 23a in a first vertical plane, and a second rotation mechanism 23b that rotates the table 23a about a second rotation center P2 above the table 23a in a second vertical plane perpendicular to the first vertical plane. The load detection device 20 includes a stage 23 having a first rotation center P1 overlapping with the mold 1 in a first vertical plane and a second rotation center P2 overlapping with the mold 1 in a second vertical plane, and a calculation device 30 that executes a center of gravity position calculation process that calculates a center of gravity position G of the load based on the detection result of the load detection device 20, and an adjustment process that controls the first rotation mechanism 23b and the second rotation mechanism 23c of the stage 23 so that the tilt angle α of the central axis C2 of the movable mold 2 relative to the central axis C3 of the fixed mold 3 is reduced based on the center of gravity position G calculated in the center of gravity position calculation process. With this configuration, the influence of tilt and decentering of the mold 1 can be reduced, and the shape accuracy of the molded product can be improved.

[0088] Furthermore, in the molding system 100, the first rotation center P1 overlaps with the molding material 5 arranged between the fixed die 3 and the movable die 2 of the mold 1 in the first vertical plane. The second rotation center P2 overlaps with the molding material 5 arranged between the fixed die 3 and the movable die 2 of the mold 1 in the second vertical plane. With this configuration, the effect of the decentering of the mold 1 can be easily reduced.

[0089] Furthermore, in the molding system 100, the first rotation center P1 is closer to the center of the mold 1 than to the outside of the mold 1 in the first vertical plane. The second rotation center P2 is closer to the center of the mold 1 than to the outside of the mold 1 in the second vertical plane. This configuration makes it easier to reduce the effects of decentering of the mold 1.

[0090] Furthermore, the first rotation center P1 and the second rotation center P2 are at the same position in the molding system 100. With this configuration, the effects of tilt and decentering of the mold 1 can be reduced, and the shape accuracy of the molded product can be improved.

[0091] The molding system 100 further includes an adjustment member (second heat insulating material 8b) disposed between the table 23a and the mold 1 so that the mold 1 overlaps the first rotation center P1 in the first vertical plane and overlaps the second rotation center P2 in the second vertical plane. This configuration makes it easy to adjust the positions of the mold 1 relative to the first rotation center P1 and the second rotation center P2.

[0092] Moreover, in the molding system 100, the load detection device 20 includes three or more load sensors 21 arranged between the table 23a and the mold 1 so as not to be aligned in a straight line in a plane perpendicular to the central axis C3 of the fixed mold 3. The center of gravity position calculation process calculates the center of gravity position G of the load based on the outputs of the three or more load sensors 21 of the load detection device 20. This configuration improves the detection accuracy of the center of gravity position G.

[0093] In addition, in the molding system 100, the calculation device 30 executes an adjustment process when the tilt angle α calculated from the center of gravity G of the load calculated based on the detection result of the load detection device 20 after execution of press molding exceeds a predetermined angle threshold. With this configuration, the tilt of the die 1 can be corrected during press molding, and the correction can be confirmed as it proceeds.

[0094] Furthermore, in the molding system 100, the calculation device 30 executes an adjustment process when the center of gravity G of the load calculated based on the detection result of the load detection device 20 during press molding is not within a predetermined distance threshold range from the central axis C3 of the fixed die 3. According to this configuration, the tilt of the die 1 can be corrected in real time during press molding, improving the yield.

[0095] The molding system 100 further includes a heating mechanism 7 that heats the molding material 5 through the mold 1, and a drive mechanism 9 that relatively moves the movable mold 2 toward the fixed mold 3 of the mold 1. With this configuration, the effects of tilt and decentering of the mold 1 can be reduced, improving the shape accuracy of the molded product.

[0096] In other words, the molding system 100 executes the following method (molding method). The molding method is executed by the calculation device 30 connected to the load detection device 20 and the stage 23. The load detection device 20 detects the load received from the mold 1 in relation to press molding of the molding material 5, which is performed by using a mold 1 having a fixed mold 3 and a movable mold 2 that sandwich the molding material 5 in the vertical direction and moving the movable mold 2 toward the fixed mold 3. The stage 23 has a table 23a on which the mold 1 is placed, a first rotation mechanism 23b that rotates the table 23a about a first rotation center P1 above the table 23a in a first vertical plane, and a second rotation mechanism 23c that rotates the table 23a about a second rotation center P2 above the table 23a in a second vertical plane perpendicular to the first vertical plane, and the first rotation center P1 overlaps with the mold 1 in the first vertical plane, and the second rotation center P2 overlaps with the mold 1 in the second vertical plane. The molding method includes a center-of-gravity position calculation process for calculating the center-of-gravity position G of the load based on the detection result of the load detection device 20, and an adjustment process for controlling the first rotation mechanism 23b and the second rotation mechanism 23c of the stage 23 so as to reduce the tilt angle α of the central axis C2 of the movable mold 2 relative to the central axis C3 of the fixed mold 3 based on the center-of-gravity position G calculated in the center-of-gravity position calculation process. With this configuration, the effects of tilt and decentering of the mold 1 can be reduced, improving the shape accuracy of the molded product.

[0097] The above molding method can be realized by the calculation device 50 executing the program D32. This program D32 is a computer program for causing the calculation device 50 to execute the above molding method. With this configuration, it is possible to reduce the influence of tilt and decentering of the mold 1 and improve the shape accuracy of the molded product.

[0098] [1.2 Second embodiment] Fig. 12 is a schematic diagram of a configuration example of a molding system 100A of embodiment 2. Unlike molding system 100 of Fig. 1, molding system 100A of Fig. 12 includes a plurality of heating mechanisms 7 and a plurality of driving mechanisms 9. Molding system 100A includes a plurality of heating mechanisms 7 and a plurality of driving mechanisms 9. Molding system 100A is an example of a glass lens molding device that divides the press molding process of a glass lens into multiple stages and is capable of producing glass lenses using a plurality of dies 1, and is capable of increasing productivity compared to molding system 100 of Fig. 1.

[0099] The molding system 100A of Fig. 12 will be described in more detail below. The molding system 100A of Fig. 12 includes a housing 55 supported by supports 54 on a stand 51. The inside of the housing 55 forms a processing chamber 55a. The processing chamber 55a is controlled in a vacuum or nitrogen atmosphere to prevent oxidation of the mold. The housing 55 includes an input section shutter 11a at an entrance for inputting the mold 1 into the processing chamber 55a, and an output section shutter 11b at an exit for removing the mold 1 from the processing chamber 55a.

[0100] The molding system 100A includes a plurality of molding blocks 10-1 to 10-4 (hereinafter collectively referred to as 10) for press-molding a molding material 5 in a processing chamber 55a of a housing 55. Each molding block 10 includes a heating mechanism 7 and a driving mechanism 9.

[0101] In forming blocks 10-1 and 10-4, second heater block 7b is placed on a heat insulating plate 8 arranged on the bottom surface of housing 55. First heater block 7a is arranged to face second heater block 7b in the vertical direction, and is movable in the vertical direction by drive mechanism 9.

[0102] Each of the molding blocks 10-2 and 10-3 further includes a load detection device 20, a stage 23, a calculation device 30, and a control device 34, and is capable of correcting the tilt of the mold 1. The stage 23 of the molding blocks 10-2 and 10-3 is disposed on a stand 51. The load sensor 21 of the load detection device 20 is disposed on the stage 23. The top plate 52 is disposed on the load sensor 21. The stage 23 can rotate the top plate 52 about the first rotation center P1 by the first rotation mechanism 23b, and can rotate the top plate 52 about the second rotation center P1 by the second rotation mechanism 23c. The top plate 52 is exposed inside the housing 55 from an opening 55b on the bottom surface of the housing 55. The top plate 52 is connected to the housing 55 by the bellows 53 so that no gap is generated between the top plate 52 and the opening 55b of the housing 55. The bellows 53 is configured not to hinder the rotation of the top plate 52 by the stage 23. The second heater block 7b is placed on a heat insulating plate 8 arranged on the top plate 52. The first heater block 7a is arranged to face the second heater block 7b in the vertical direction, and is movable in the vertical direction by a drive mechanism 9.

[0103] In the molding system 100A of Fig. 12, the press molding process includes a throwing process, a heating process, a molding process, a first cooling process, a second cooling process, and a removal process. A plurality of molding blocks 10-1 to 10-4 are responsible for the heating process, the molding process, the first cooling process, and the second cooling process, respectively. In each of the molding blocks 10-1 to 10-4 corresponding to the heating process, the molding process, the first cooling process, and the second cooling process, the temperatures of the first heater block 7a and the second heater block 7b are controlled to be predetermined temperatures for the corresponding process. In the molding system 100A, the mold 1 is transferred and transported in sequence to locations corresponding to the processes at regular cycle times (e.g., 10 minutes), whereby press molding of a plurality of glass lenses is performed simultaneously. In FIG. 12, in molding system 100A, the locations corresponding to the inserting process, heating process, molding process (press molding process), first cooling process, second cooling process, and removal process (lens removal process) are labeled "inserting," "heating," "molding," "cooling 1," "cooling 2," and "removal" to clearly indicate the locations corresponding to the inserting process, heating process, molding process (press molding process), first cooling process, second cooling process, and removal process (lens removal process), respectively.

[0104] Each step of the press molding will be described below. In the following description, in order to easily distinguish between the molding material 5 before and after the shape change due to press molding, the molding material 5 before the shape change due to press molding is given the reference symbol 5a, and the molding material 5 after the shape change due to press molding is given the reference symbol 5b.

[0105] In the loading step, the movable die 2 is removed from the die 1, and the molding material 5a is placed on the fixed die 3. Thereafter, the movable die 2 is inserted into the sleeve 4, and the molding material 5a is sandwiched between the fixed die 3 and the movable die 2. After this, the die 1 is transported into the processing chamber 55a of the housing 55, for example, by a transfer / transport mechanism, and placed in the center of the second heater block 7b of the molding block 10-1 corresponding to the heating step. The loading section shutter 11a opens immediately before the transfer / transport of the die 1, and closes immediately after the die 1 is placed in the center of the second heater block 7b of the molding block 10-1, thereby preventing a drop in the atmospheric temperature in the processing chamber 55a.

[0106] In the heating step, the heating mechanism 7 of the molding block 10-1 raises the temperature of the molding material 5a, which is a glass material, to a temperature at which the molding material 5a can be softened and molded. In the heating step, the press shaft 9b of the driving mechanism 9 is lowered to hardly apply a load to the molding material 5a by the first heater block 7a, in order to heat the molding material 5a, and the first heater block 7a approaches or contacts the movable die 2 of the mold 1 to raise the temperature. In particular, since the temperature of the mold 1 immediately after being placed on the second heater block 7b of the molding block 10-1 is lower than the set temperature of the heating mechanism 7, the driving mechanism 9 hardly applies a load in this heating step. The reason is that if a large load is applied when the temperature of the molding material 5a, which is a glass material, is low, the molding material 5a may crack, or the surfaces of the movable die 2 and the fixed die 3 may be scratched or dented. In the latter half of the heating step, the molding material 5a reaches a temperature at which it can be sufficiently thermally deformed. After the mold 1 is heated for a certain period of time in the heating step, it is transferred and conveyed to the molding block 10-2 corresponding to the molding step, and the next mold 1 is inserted into the molding block 10-1 corresponding to the heating step in the insertion step.

[0107] In the molding process, the press shaft 9b of the drive mechanism 9 is lowered, and the first heater block 7a applies a load to the molding material 5a, which thermally deforms the molding material 5a, transferring the shape of the mold to the molding material 5a, thereby obtaining a molding material 5b with a changed shape. After a certain period of time has elapsed again, the mold 1 is sent to the molding block 10-3 corresponding to the first cooling process, and the next mold 1 from the molding block 10-1 corresponding to the heating process is placed in the molding block 10-2 corresponding to the molding process.

[0108] In the first cooling step, a load is applied to the movable die 2 in the same manner as in the molding step. The load applied in the first cooling step is smaller than the load applied in the molding step because the load is intended to hold the die 1 for transfer. The set temperature of the heating mechanism 7 in the first cooling step is controlled to be lower than the set temperature of the heating mechanism 7 in the molding step. In the first cooling step, the temperature of the molding material 5b is lowered, causing the molding material 5b to contract, completing the transfer of the mold shapes of the movable die 2 and the fixed die 3 to the molding material 5b. After a certain time has passed, the die 1 is sent to the molding block 10-4 corresponding to the second cooling step, and the next die 1 from the molding block 10-2 corresponding to the molding step is placed in the molding block 10-3 corresponding to the first cooling step.

[0109] In the second cooling step, the first heater block 7a is lowered by the press shaft 9b of the drive mechanism 9 and approaches or comes into contact with the movable die 2, thereby cooling the die 1 and the molding material 5b. The purpose of the second cooling step is to cool the molding material 5b so that it can be removed from the processing chamber 55a in the next removal step. For this reason, the temperature of the heating mechanism 7 in the second cooling step is controlled to be much lower than the temperature of the heating mechanism 7 in the first cooling step. After a certain time has passed, the die 1 is removed from the processing chamber 55a to the outside, and the next die 1 from the molding block 10-3 corresponding to the first cooling step is placed in the molding block 10-4 corresponding to the second cooling step. The removal unit shutter 11b opens immediately before the transfer and transportation of the die 1 and closes immediately after the die 1 is removed from the processing chamber 55a, thereby preventing a drop in the atmospheric temperature of the processing chamber 55a.

[0110] In the removal step, the mold 1 removed from the processing chamber 55a is disassembled, and the molding material 5b is removed from the mold 1. The step of disassembling the mold 1 and removing the molding material 5b may be automated by a machine to increase productivity.

[0111] Thereafter, the mold 1 is assembled to accommodate a new molding material 5a, and then is loaded into the processing chamber 55a of the molding system 100A in a loading step.

[0112] In the press molding process of the glass lens by the molding system 100A described above, the heating process and the cooling process may be divided into more steps according to the type of glass material and the molding tact time. The set temperature of the heating mechanism 7 often differs for each process, and the temperature is generally high in the heating process and the molding process, and low in the cooling processes such as the first cooling process and the second cooling process. For example, the set temperature of the heating mechanism 7 in the molding process, which of course differs depending on the characteristics of the molding material 5a, may be set to around 600°C because a temperature exceeding the glass transition point and near the yield point is required. The set temperature of the heating mechanism 7 in the first cooling process following the molding process is lower than that in the molding process, and the set temperature of the heating mechanism 7 in the second cooling process is set to a temperature at which removal is possible, so it is much lower than that in the first cooling process.

[0113] In the molding system 100A of FIG. 12, the tilt of the mold 1 can be corrected in each of the molding block 10-2 in charge of the molding process and the molding block 10-3 in charge of the first cooling process. In the molding process, the load applied to the mold 1 by the drive mechanism 9 is large, and the molding material 5 is significantly deformed, so that the mold 1 is likely to be tilted. In the first cooling process, the temperature is often set near the glass transition point, and the molding material 5 is not significantly deformed by heat, but the shape of the final molded product is formed. From this point of view, in the molding system 100A, the tilt of the mold 1 can be corrected in the molding process and the first cooling process. According to the molding system 100A, like the molding system 100, the influence of the tilt and decentering of the mold can be reduced to improve the shape accuracy of the molded product.

[0114] [2. Modifications] The embodiments of the present disclosure are not limited to the above-mentioned embodiments. The above-mentioned embodiments can be modified in various ways depending on the design, etc., as long as the object of the present disclosure can be achieved. Below, modified examples of the above-mentioned embodiments are listed. The modified examples described below can be applied in appropriate combination.

[0115] In one modified example, the molding material 5 is not limited to a glass material, and may be a resin material such as PET. The mold 1 is not limited to a mold for a lens. In other words, the molded product is not limited to a lens, and may be a preform or other article.

[0116] In one modified example, the load detection device 20 does not necessarily have to include the amplifier 22. The number of the load sensors 21 is not limited to three or four.

[0117] In one modified example, the stage 23 is not necessarily limited to a two-axis swivel stage. The stage 23 may be configured so that the table 23a can rotate about a first rotation center P1 in a first vertical plane and the table 23a can rotate about a second rotation center P2 in a second vertical plane. In addition, the first rotation center P1 and the second rotation center P2 do not necessarily have to be at the same position. Depending on the configuration of the stage 23, the control device 34 may be omitted.

[0118] In one modified example, the arithmetic device 30 may be realized by a plurality of computer systems, not a single computer system. In other words, it is not essential that a plurality of functions (components) of the arithmetic device 30 are integrated in one housing, and each component of the arithmetic device 30 may be distributed across a plurality of housings. Furthermore, at least some of the functions of the arithmetic device 30 may be realized by the cloud (cloud computing) or the like.

[0119] 12, the forming blocks 10-1, 10-4 may also be equipped with a load detection device 20, a stage 23, an arithmetic device 30, and a control device 34, and may be capable of correcting the tilt of the die 1. Furthermore, at least one of the multiple forming blocks 10 may be capable of correcting the tilt of the die 1. The forming system 100A may be capable of correcting the tilt of the die 1 in at least one of the multiple steps of press forming.

[0120] [3. Aspects] As is apparent from the above-described embodiment and modified examples, the present disclosure includes the following aspects. In the following, reference symbols are given in parentheses only to clarify the correspondence with the embodiment.

[0121] The first aspect is a molding system (100; 100A) including a mold (1) having a fixed mold (3) and a movable mold (2) that sandwich a molding material (5) in a vertical direction, and a load detection device (20) that detects a load received from the mold (1) in press molding of the molding material (5) performed by relatively moving the movable mold (2) toward the fixed mold (3), a table (23a) on which the mold (1) is placed, a first rotation mechanism (23b) that rotates the table (23a) about a first rotation center (P1) above the table (23a) in a first vertical plane, and a second rotation mechanism (23b) that rotates the table (23a) about a second rotation center (P2) above the table (23a) in a second vertical plane perpendicular to the first vertical plane. The load detection device (20) includes a stage (23) having a first rotation mechanism (23b) and a second rotation mechanism (23c) for rotating a center axis (C2) of the movable mold (2) relative to a center axis (C3) of the fixed mold (3), the first rotation center (P1) overlapping with the mold (1) in the first vertical plane and the second rotation center (P2) overlapping with the mold (1) in the second vertical plane, and a calculation device (30) for executing a center-of-gravity position calculation process for calculating a center-of-gravity position (G) of the load based on a detection result of the load detection device (20) and an adjustment process for controlling the first rotation mechanism (23b) and the second rotation mechanism (23c) of the stage (23) so as to reduce a tilt angle (α) of a center axis (C2) of the movable mold (2) relative to a center axis (C3) of the fixed mold (3). According to this aspect, the influence of tilt and decentering of the mold (1) can be reduced, thereby improving the shape accuracy of the molded product.

[0122] The second aspect is a molding system (100; 100A) based on the first aspect. In the second aspect, the first rotation center (P1) overlaps with the molding material (5) arranged between the fixed mold (3) and the movable mold (2) of the mold (1) in the first vertical plane. The second rotation center (P2) overlaps with the molding material (5) arranged between the fixed mold (3) and the movable mold (2) of the mold (1) in the second vertical plane. According to this aspect, it becomes easier to reduce the influence of decentering of the mold (1).

[0123] The third aspect is a molding system (100; 100A) based on the first or second aspect. In the third aspect, the first rotation center (P1) is closer to the center of the mold (1) than the outside of the mold (1) in the first vertical plane. The second rotation center (P2) is closer to the center of the mold (1) than the outside of the mold (1) in the second vertical plane. According to this aspect, it is easier to reduce the effect of decentering of the mold (1).

[0124] The fourth aspect is a molding system (100; 100A) based on any one of the first to third aspects. In the fourth aspect, the first rotation center (P1) and the second rotation center (P2) are at the same position. According to this aspect, the influence of tilt and decentering of the mold (1) can be reduced, thereby improving the shape accuracy of the molded product.

[0125] A fifth aspect is a molding system (100; 100A) based on any one of the first to fourth aspects. In the fifth aspect, the molding system (100) further includes an adjustment member (second insulating material 8b; insulating plate 8) disposed between the table (23a) and the mold (1) so that the mold (1) overlaps with the first rotation center (P1) in the first vertical plane and overlaps with the second rotation center (P2) in the second vertical plane. According to this aspect, it becomes easy to adjust the positions of the mold (1) relative to the first rotation center (P1) and the second rotation center (P2).

[0126] The sixth aspect is a molding system (100; 100A) based on any one of the first to fifth aspects. In the sixth aspect, the load detection device (20) includes three or more load sensors (21) that are arranged between the table (23a) and the mold (1) so as not to be aligned in a straight line in a plane perpendicular to the central axis (C3) of the fixed mold (3). The center of gravity position calculation process calculates the center of gravity position (G) of the load based on the outputs of the three or more load sensors (21) of the load detection device (20). According to this aspect, the detection accuracy of the center of gravity position (G) can be improved.

[0127] The seventh aspect is a molding system (100; 100A) based on any one of the first to sixth aspects. In the seventh aspect, the arithmetic device (30) executes the adjustment process when the tilt angle (α) calculated from the center of gravity position (G) of the load calculated based on the detection result of the load detection device (20) after the press molding is performed exceeds a predetermined angle threshold. According to this aspect, the tilt of the die (1) can be corrected during press molding, and the correction can be confirmed as it proceeds.

[0128] The eighth aspect is a molding system (100; 100A) based on any one of the first to sixth aspects. In the eighth aspect, the arithmetic device (30) executes the adjustment process when the center of gravity position (G) of the load calculated based on the detection result of the load detection device (20) during the execution of the press molding is not within a predetermined distance threshold range from the center axis (C3) of the fixed die (3). According to this aspect, the tilt of the die (1) can be corrected in real time during the press molding, and the yield can be improved.

[0129] A ninth aspect is a molding system (100; 100A) based on any one of the first to eighth aspects. In the ninth aspect, the molding system (100; 100A) further includes a heating mechanism (7) that heats the molding material (5) through the mold (1), and a drive mechanism (9) that relatively moves the movable mold (2) toward the fixed mold (3) of the mold (1). According to this aspect, the influence of tilt and decenter of the mold (1) can be reduced, thereby improving the shape accuracy of the molded product.

[0130] The tenth aspect is a molding method executed by a calculation device (30) connected to a load detection device (20) and a stage (23). The load detection device (20) detects a load received from a mold (1) having a fixed mold (3) and a movable mold (2) that sandwich a molding material (5) in a vertical direction, in press molding of the molding material (5) performed by moving the movable mold (2) toward the fixed mold (3). The stage (23) has a table (23a) on which the mold (1) is placed, a first rotation mechanism (23b) that rotates the table (23a) about a first rotation center (P1) above the table (23a) in a first vertical plane, and a second rotation mechanism (23c) that rotates the table (23a) about a second rotation center (P2) above the table (23a) in a second vertical plane perpendicular to the first vertical plane, such that the first rotation center (P1) overlaps with the mold (1) in the first vertical plane, and the second rotation center (P2) overlaps with the mold (1) in the second vertical plane. The molding method includes a center of gravity calculation process for calculating the center of gravity (G) of the load based on the detection result of the load detection device (20), and an adjustment process for controlling the first rotation mechanism (23b) and the second rotation mechanism (23c) of the stage (23) so as to reduce the tilt angle (α) of the central axis (C2) of the movable mold (2) relative to the central axis (C3) of the fixed mold (3) based on the center of gravity (G) calculated in the center of gravity calculation process. According to this aspect, the influence of tilt and decentering of the mold (1) can be reduced, thereby improving the shape accuracy of the molded product.

[0131] An eleventh aspect is a program (D32) for causing the arithmetic device (30) to execute the molding method of the tenth aspect. According to this aspect, it is possible to reduce the influence of tilt and decentering of the mold (1) and improve the shape accuracy of the molded product.

[0132] The second to ninth aspects can also be modified appropriately and applied to the tenth aspect. [Industrial Applicability]

[0133] The present disclosure is applicable to a molding system, a molding method, and a program (computer program). Specifically, the present disclosure is applicable to a molding system, a molding method, and a program (computer program) that perform press molding of a molding material using a die. [Explanation of symbols]

[0134] 100,100A molding system 1. Mold 2 Movable type 3 Fixed type 5 Molding material 7 Heating mechanism 8. Insulation board (adjustment material) 8b Second insulation material (adjustment material) 9 Drive mechanism 20 Load detection device 21 Load sensor 23 Stage 23a Table 23b First rotating mechanism 23c Second rotation mechanism 30 Arithmetic unit C2 center axis C3 center axis α Tilt angle P1 First rotation center P2 Second rotation center G Center of gravity position

Claims

1. A load detection device detects a load received from a die in press molding of a molding material, the press molding being performed by using a die having a fixed die and a movable die that sandwich a molding material in a vertical direction and relatively moving the movable die toward the fixed die; a stage including a table on which the mold is placed, a first rotation mechanism that rotates the table about a first rotation center above the table in a first vertical plane, and a second rotation mechanism that rotates the table about a second rotation center above the table in a second vertical plane perpendicular to the first vertical plane, the first rotation center overlapping the mold in the first vertical plane and the second rotation center overlapping the mold in the second vertical plane; a calculation device that executes a center-of-gravity position calculation process that calculates a center-of-gravity position of the load based on a detection result of the load detection device, and an adjustment process that controls the first rotation mechanism and the second rotation mechanism of the stage based on the center-of-gravity position calculated in the center-of-gravity position calculation process so as to reduce a tilt angle of a central axis of the movable mold relative to a central axis of the fixed mold; Equipped with Molding system.

2. the first rotation center overlaps with the molding material disposed between the fixed die and the movable die of the mold within the first vertical plane; The second rotation center overlaps with the molding material disposed between the fixed mold and the movable mold of the mold in the second vertical plane. The molding system of claim 1 .

3. the first center of rotation is closer to a center of the mold than to an outside of the mold in the first vertical plane; The second center of rotation is closer to the center of the mold than to the outside of the mold in the second vertical plane. The molding system according to claim 1 or 2.

4. The first rotation center and the second rotation center are at the same position. The molding system according to any one of claims 1 to 3.

5. an adjustment member disposed between the table and the mold such that the mold overlaps the first rotation center in the first vertical plane and overlaps the second rotation center in the second vertical plane; The molding system according to any one of claims 1 to 4.

6. the load detection device includes three or more load sensors disposed between the table and the mold so as not to be aligned in a straight line within a plane perpendicular to a central axis of the fixed mold, the center of gravity position calculation process calculates a center of gravity position of the load based on outputs of the three or more load sensors of the load detection device. The molding system according to any one of claims 1 to 5.

7. the calculation device executes the adjustment process when the tilt angle calculated from the center of gravity position of the load calculated based on the detection result of the load detection device after the execution of the press forming exceeds a predetermined angle threshold value. The molding system according to any one of claims 1 to 6.

8. the calculation device executes the adjustment process when a center of gravity position of the load calculated based on a detection result of the load detection device during execution of the press forming is not within a range of a predetermined distance threshold from a central axis of the fixed die. The molding system according to any one of claims 1 to 6.

9. A heating mechanism for heating the molding material through the mold; a drive mechanism for relatively moving the movable die toward the fixed die of the metal mold; Further comprising: The molding system according to any one of claims 1 to 7.

10. A molding method executed by a calculation device connected to a load detection device and a stage, The load detection device detects a load received from a die in press molding of the molding material, the press molding being performed by using a die having a fixed die and a movable die that sandwich the molding material in a vertical direction and relatively moving the movable die toward the fixed die; The stage includes a table on which the mold is placed, a first rotation mechanism that rotates the table about a first rotation center above the table in a first vertical plane, and a second rotation mechanism that rotates the table about a second rotation center above the table in a second vertical plane perpendicular to the first vertical plane, the first rotation center overlapping the mold in the first vertical plane, and the second rotation center overlapping the mold in the second vertical plane, The molding method includes: a center-of-gravity position calculation process for calculating a center-of-gravity position of the load based on a detection result of the load detection device; an adjustment process of controlling the first rotation mechanism and the second rotation mechanism of the stage so that a tilt angle of a central axis of the movable mold with respect to a central axis of the fixed mold is reduced based on the center of gravity position calculated in the center of gravity position calculation process; Including, Molding method.

11. The molding method according to claim 10 is executed by the computing device. program.

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