JP4463534B2 - Molding apparatus, molded product and mold relative distance measuring method - Google Patents

Description

  The present invention relates to a molding apparatus, a molded product, and a mold relative distance measuring method.

  Conventionally, a molded product made of a material such as glass or resin is subjected to press molding after the glass material or resin material is put into a mold for molding of a press device as a molding device, heated and softened. Molded. In this case, a glass molded product or a resin molded product having a shape corresponding to the shape of the cavity of the mold composed of the upper mold and the lower mold is molded. Then, after the glass molded product or resin molded product is molded, the upper mold is raised or the lower mold is lowered to open the glass molded product or resin remaining on the lower mold. The molded product is taken out by a conveying member provided with suction means or the like and conveyed to a subsequent process.

  By the way, when the said molded article is a precision member, it is requested | required to raise the precision of the thickness of a molded article. For example, when the molded product is an optical element such as a lens, the accuracy of the thickness of the optical element greatly affects the performance of the optical element. Therefore, the upper mold and the lower mold are fitted in a concave-convex manner, or the upper mold in a closed state is pressed by pressing the mold mating surface of the upper mold and the mold mating surface of the lower mold. A method is generally employed in which the relative distance between the mold and the lower mold is always kept constant. However, in the above method, since the upper mold and the lower mold are in physical contact with each other, the life of the mold is shortened. In addition, in order to keep the relative distance between the upper mold and the lower mold constant with high accuracy, it is necessary to process the fitting part and mold mating surface of the upper mold and the lower mold with high precision. The cost of the mold becomes high. In addition, in the above method, the accuracy of the thickness of the molded product is limited to about ± 10 [μm], and the accuracy cannot be further increased.

Therefore, a molding apparatus that measures the relative distance between the upper mold and the lower mold using a displacement sensor has been proposed (see, for example, Patent Document 1). As a result, the position of the upper mold or the lower mold can be controlled with high accuracy, so that a molded product with high thickness accuracy can be obtained, and there is no need to process the mold with high accuracy. Therefore, the manufacturing cost of a metal mold | die can be reduced, and also it can prevent that a metal mold | die is damaged.
JP 2003-54969 A

  However, in the conventional molding apparatus, the relative distance between the upper mold and the lower mold is not measured directly, but indirectly, so that the relative distance between the upper mold and the lower mold is sufficiently accurate. It was not possible to measure. That is, in the case of the conventional molding apparatus, the displacement sensor is attached at a position away from the die mating surfaces of the upper die and the lower die on the press shaft for driving the upper die and the lower die. In addition, the amount of thermal expansion of the press shaft is estimated by measuring the temperature of the press shaft at several points between the displacement sensor and the die mating surface. The estimated thermal expansion amount is added to or subtracted from the displacement amount of the press shaft measured by the displacement sensor, and the relative distance between the upper die and the lower die is indirectly measured. Therefore, the measured relative distance between the upper mold and the lower mold includes an error such as the thermal expansion amount of the press shaft, and the accuracy is lowered. Therefore, in the conventional molding apparatus, it has been impossible to mold a sufficiently high-precision molded product.

  The present invention solves the problems of the conventional molding apparatus, and corrects the relative distance between the molds measured by the distance measuring means according to the temperature measured by the temperature measuring means, so that It is an object of the present invention to provide a molding apparatus, a molded product, and a mold relative distance measuring method capable of accurately measuring the distance and improving the quality of the molded product.

Therefore, in the molding apparatus of the present invention includes a pair of molds, and a temperature measurement means for measuring a distance measuring means for measuring the relative distance between the mold, the temperature of the distance measurement hand stage, the Correction means for correcting the relative distance between the molds measured by the distance measuring means according to the temperature measured by the temperature measuring means.

In another molding apparatus of the present invention, said correcting means, said distance measuring means and the temperature at which in a state where the relative distance between the die and the predetermined value is varied the temperature of said distance measuring hand stage The relative distance between the molds measured by the distance measuring unit is corrected by a temperature correction table created based on the measurement value of the measuring unit.

  In still another molding apparatus of the present invention, the relative distance between the molds is set to a predetermined value by sandwiching a calibration block between the molds.

  In still another molding apparatus of the present invention, the distance measuring unit further measures a displacement between the molds.

In still another molding apparatus of the present invention, the distance measuring means and the temperature measuring means are arranged in one or the other mold .

  The molded article of the present invention was molded by the molding apparatus of the present invention.

In the mold relative distance measuring method of the present invention, the step distance measuring means, the steps of measuring a relative distance between a pair of molds, temperature measuring means, for measuring the temperature of said distance measuring hand stage, correction And means for correcting the relative distance between the molds measured by the distance measuring means according to the temperature measured by the temperature measuring means.

In other mold relative distance measuring method of the present invention, furthermore, the correction means, said distance when in a state where the relative distance between the die and the predetermined value is varied the temperature of said distance measuring hand stage The relative distance between the molds measured by the distance measuring unit is corrected by a temperature correction table created based on the measurement values of the measuring unit and the temperature measuring unit.

  In still another mold relative distance measuring method of the present invention, the relative distance between the molds is set to a predetermined value by sandwiching a calibration block between the molds.

  According to the present invention, the molding apparatus includes a pair of molds, a distance measuring unit for measuring a relative distance between the molds, and a temperature for measuring the distance measuring unit or a temperature in the vicinity of the distance measuring unit. Measuring means; and correction means for correcting the relative distance measured by the distance measuring means in accordance with the temperature measured by the temperature measuring means.

  In this case, the relative distance between the molds is directly measured by correcting the relative distance measured by the distance measuring means for measuring the relative distance between the molds according to the temperature measured by the temperature measuring means, and Since the measured value is corrected based on the temperature in the vicinity of the distance meter, the relative distance between the molds can be accurately measured, and the quality of the molded product can be improved.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The press device as the molding device in the present embodiment is suitable for molding a molded product made of a material such as glass or resin, and mainly a mold for molding a glass material or a resin material. It is used for press molding after being charged into an apparatus, heated and softened, but may be used for molding a molded article made of any material. That is, in addition to glass and resin, for example, it can be used to form a molded article made of various materials such as metal, ceramics, paper, and fibers, or a material obtained by appropriately mixing these materials. In the present embodiment, for the sake of explanation, a case where a molded product made of glass is molded will be described.

  FIG. 1 is a schematic diagram showing the configuration of a press apparatus according to the first embodiment of the present invention.

  In the figure, 10 is a pressing device as a molding device, 11b is a base frame as a part of the frame 11 of the pressing device 10, and 11a is a guide frame as a part of the frame 11 of the pressing device 10. Here, the guide frame 11a has a cylindrical shape standing upright as a whole, and its lower end is attached to the upper surface of the base frame 11b. Note that the base frame 11b and the guide frame 11a will be described as the frame 11 when they are described in an integrated manner.

  Inside the guide frame 11a, a movable table device mounting member 12 is mounted on the upper surface of the base frame 11b, and a movable surface as a mold position adjusting device is mounted on the upper surface as the mounting surface of the movable table device mounting member 12. A table device 13 is attached. The movable table device 13 is, for example, an XY table device, and includes a movable table movable in a horizontal plane (a plane perpendicular to the long axis of the guide frame 11a), and a lower mold is supported on the upper surface of the movable table. A member 14 is attached. Furthermore, on the upper surface of the lower mold support member 14, one mold in the mold apparatus, that is, a lower mold 21 as a fixed mold is attached. The lower mold 21 is heated by heating means (not shown) such as an electric heater built in the lower mold support member 14. Here, on the upper surface of the lower mold 21, there are formed a planar mold mating surface 21a, which will be described later, and a cavity 21b having a shape that forms a substantially lower half of the molded product. .

  Further, an upper mold carriage 15 as a mold driving member is attached to the upper part inside the guide frame 11a so as to be movable in the vertical direction (long axis direction of the guide frame 11a). Here, the upper mold carriage 15 is guided by a guide mechanism 16 including a linear guide mechanism having a circulating ball or the like, and the movement locus may sway horizontally along the inner surface of the guide frame 11a. It can move smoothly. Further, the outer surface of the upper mold carriage 15 and the inner surface of the guide frame 11a are always kept in parallel so that the upper mold carriage 15 is not inclined. The guide mechanism 16 may be a hydrostatic bearing device that injects a pressure fluid between the outer surface of the upper mold carriage 15 and the inner surface of the guide frame 11a.

  A driving device 17 as a movable mold driving source is disposed above the upper mold carriage 15. The driving device 17 is fixed to the guide frame 11a via an attachment member (not shown). Further, the connecting rod 17a of the driving device 17 projects downward, and the upper mold carriage 15 is attached to the lower end of the connecting rod 17a. Here, the drive device 17 is, for example, a cylinder device including a piston driven by a high-pressure fluid. In this case, the lower end portion of the piston rod attached to the piston is connected to the upper end portion of the connecting rod 17a. Then, by switching the flow of the pressure fluid supplied to the cylinder device, the piston is driven upward or downward, whereby the connecting rod 17a and the upper mold carriage 15 are moved upward or downward. Be made. Here, although the said pressure fluid is air, for example, other gas, such as nitrogen gas, may be sufficient as liquids, such as oil.

  Further, the driving device 17 may be an electric motor instead of a cylinder device, and may be, for example, a linear motor. In this case, the lower end portion of a reciprocating member (slider) as a rotor is connected to the upper end portion of the connecting rod 17a. Then, by switching the current supplied to the linear motor, the slider is driven upward or downward with respect to a fixing member as a stator, whereby the connecting rod 17a and the upper mold carriage 15 are moved upward. Alternatively, it is moved downward. The driving device 17 may be a rotary electric motor such as a servo motor. In this case, the rotation of the rotating shaft is converted into a reciprocating motion by a motion direction converting device such as a ball screw nut. It is transmitted to the connecting rod 17a.

  An upper mold support member 18 is attached to the lower surface of the upper mold carriage 15, and the lower surface of the upper mold support member 18 is attached to the other mold in the mold apparatus, that is, the upper mold as a movable mold. A mold 22 is attached. The upper mold 22 is heated by a heating means (not shown) such as an electric heater built in the upper mold support member 18. Here, on the lower surface of the upper mold 22, there are formed a planar mold mating surface 22a, which will be described later, and a cavity 22b having a shape that forms a substantially upper half of the molded product. .

  As described above, in the present embodiment, for the sake of explanation, a case where a molded product made of glass is formed will be described. Therefore, the forming material is a glass material as a glass material. The molded product is an optical element such as a lens, a prism, a filter, or a mirror. The material is transported by a transport device (not shown) such as a handling device including a transport arm and a holding device that holds the material attached to the tip of the transport arm. Then, the conveying device enters the inside of the guide frame 11a through an opening (not shown) formed in the side surface of the guide frame 11a, and the cavity 21b of the lower die 21 of the mold device in a state where the die is opened. Material is placed on top. The material can be transported and placed by the transport device, or can be performed manually by another device or an operator.

  When the material is placed on the cavity 21 b of the lower mold 21, the upper mold carriage 15 is moved downward in the upper mold 22 located above the lower mold 21. As a result, it moves downward and approaches the lower mold 21. Subsequently, the mold is closed, and the upper mold 22 is pressed against the lower mold 21 to perform the mold clamping. In this case, when the mold is closed, the material is sandwiched in the cavity space formed by the cavity 22b and the cavity 21b. When the material is a glass material, it is generally heated to a high temperature of about 300 to 500 [° C.] and softened.

  The material of the upper mold 22 and the lower mold 21 is, for example, a tungsten alloy, a stainless alloy, a cemented carbide, or the like, but any material may be used. Further, when the material is a glass material, it is desirable that a thin film of one layer or two or more layers is formed at least on the cavity 22b and the cavity 21b in order to prevent adhesion of the glass material. The material of the thin film is, for example, hydrogenated amorphous carbon, diamond, titanium nitride, tantalum nitride, platinum iridium, platinum silicon or the like, but any material may be used.

  Subsequently, the upper mold 22 is pressed against the lower mold 21 to perform mold clamping. As a result, the glass material as a material sandwiched in the cavity space formed between the upper mold 22 and the lower mold 21 is pressed from above and below, and a glass molded product having the shape of the cavity space is molded. Is done. After the press molding is completed, the glass material is cooled until the temperature of the glass material becomes equal to or lower than the glass transition temperature. During this time, the glass material in the cavity space is continuously pressed from above and below with a force smaller than the molding force. When the temperature of the glass material becomes equal to or lower than the glass transition temperature, the driving device 17 stops operating, and thus the pressing of the glass material is finished.

  Then, when the molded product is molded, the driving device 17 is operated, and the upper mold carriage 15 is moved upward, so that the upper mold 22 moves upward and separates from the lower mold 21. The mold is opened and the molded product is taken out from the mold apparatus. It should be noted that the molded product can be taken out by the conveying device, or can be manually operated by another device or an operator.

  Here, a distance meter 23 as a distance measuring means and a temperature measuring device 24 as a temperature measuring means are attached to the upper mold supporting member 18 or the lower mold supporting member 14. The distance meter 23 and the temperature measuring device 24 may be attached to either the upper mold support member 18 or the lower mold support member 14, respectively, but in the present embodiment, the distance meter 23 and the temperature measurement are performed. The description will be made assuming that the vessel 24 is attached to the lower mold support member 14 together. The distance meter 23 measures the relative distance between the upper mold 22 and the lower mold 21 by measuring the distance between the target member 34 attached to the upper mold support member 18 and the distance meter 23 itself. It has become. That is, the distance meter 23 and the target member 34 function as a distance measurement unit and a distance measurement auxiliary unit that measure a relative distance between a pair of molds. The temperature measuring device 24 measures the temperature of the distance meter 23 or the temperature in the vicinity of the distance meter 23 in order to correct the temperature of the measurement result of the distance meter 23. The temperature measuring device 24 may be of any kind as long as it can measure the temperature, and is composed of, for example, a thermistor, a thermocouple, or the like.

  In the state shown in the drawing, a calibration block 26 is sandwiched between the upper mold 22 and the lower mold 21. The calibration block 26 is used for calibrating the distance meter 23, and a plurality of types having different known thicknesses are prepared. The calibration block 26 is preferably made of zero thermal expansion glass (anisotropic thermal expansion glass). In this case, in the normal operating temperature range of the mold apparatus, the dimension in the thickness direction of the calibration block 26 does not substantially change, that is, the thermal expansion in the thickness direction of the calibration block 26 can be ignored. it is conceivable that. Since the zero thermal expansion glass is an expensive material, the calibration block 26 can be made from a normal material having a known thermal expansion coefficient. Further, the calibration block 26 having a zero thermal expansion coefficient can be created by combining a material having a positive thermal expansion coefficient and a material having a negative thermal expansion coefficient.

  Further, the press device 10 includes a calculation means such as a CPU and an MPU, a storage means such as a magnetic disk and a semiconductor memory, an input means such as a keyboard, a joystick and a touch panel, a display means such as a CRT and a liquid crystal display, an input / output interface and the like. It has the control apparatus 25 for press apparatuses as a correction means with which it is equipped. The pressing device control device 25 is a kind of computer, receives output signals of the distance meter 23 and the temperature measuring device 24, and performs all operations of the pressing device 10 including operations of the movable table device 13 and the driving device 17. To control.

  Next, attachment positions of the distance meter 23, the temperature measuring device 24, and the target member 34 will be described.

  FIG. 2 is a diagram showing a mold apparatus to which a distance meter, a temperature measuring device, and a target member are attached according to the first embodiment of the present invention. 2 (a) is a front view of the mold apparatus, FIG. 2 (b) is a view taken in the direction of arrow A in FIG. 2 (a), a side view of the mold apparatus, and FIG. 2 (c) is FIG. FIG. 2B is a diagram showing a die-mating surface of the upper die, and FIG. 2D is a diagram showing a partial cross-section of the lower die. .

  As shown in FIG. 2, the distance meter 23 and the temperature measuring device 24 are attached to the upper surface of the lower mold support member 14 via a mounting bracket 32. The mounting bracket 32 has a curved wall shape that is shaped like a part of a side wall of a thick cylinder (sector shape) as a whole, and is the central axis of the lower mold 21, that is, the direction of the axis (FIG. 2). (A) and (b) in the vertical direction) and is disposed so as to surround a part of the side surface of the lower mold 21 from the outside. The mounting bracket 32 has a flange portion 32b formed at the lower end thereof attached to the upper surface of the lower mold support member 14 by a fixing member such as a bolt. As shown in FIG. An opening 32a is formed in the portion. A distance meter 23 and a temperature measuring device 24 are attached to the upper end surface of the mounting bracket 32 so as to be embedded. The upper end surface of the mounting bracket 32 is parallel to the mold mating surface 21 a of the lower mold 21.

  A target member 34 is attached to the lower surface of the upper mold support member 18. The target member 34 has substantially the same shape as the mounting bracket 32, and extends in the central axis of the upper mold 22, that is, in the direction of the axis (the vertical direction in FIGS. 2A and 2B). And it arrange | positions so that a part of side surface of the upper metal mold | die 22 may be enclosed from an outer side. The target member 34 has a flange portion 34b formed on the upper end thereof attached to the lower surface of the upper mold support member 18 by a fixing member such as a bolt. As shown in FIG. An opening 34a is formed in the portion. The lower end surface of the target member 34 is parallel to the mold mating surface 22 a of the upper mold 22.

  Here, the distance meter 23 is an electrostatic that measures the distance between the surface of the target member 34 facing the distance meter 23, that is, the distance between the lower end surface and the distance meter 23 itself, for example, by a change in capacitance. It is a capacitance sensor. The distance meter 23 may be of any kind as long as it can measure the displacement between the molds, that is, the displacement between the lower end surface of the target member 34 and the distance meter 23 itself. For example, a magnetic sensor, an eddy current sensor, a differential transformer, a laser beam reflection sensor, or the like may be used. The mounting bracket 32 and the target member 34 may be made of any kind of material. However, since the upper mold 22 and the lower mold 21 are at a high temperature, they have heat resistance and heat. In order to reduce the influence of the expansion on the measurement result, it is desirable that the upper mold 22 and the lower mold 21 are made of the same material. The distance meter 23 usually has a predetermined measurable range, and only when the distance between the surface of the target member 34 facing the distance meter 23 and the distance meter 23 itself is within the measurable range. The distance can be measured.

  The distance meter 23 is attached so that the upper end surface, which is the measurement surface, is at a position that is the same as or slightly lower than the mold mating surface 21 a of the lower mold 21. Further, the target member 34 is attached so that the lower end surface thereof is at the same position as or slightly higher than the mold mating surface 22 a of the upper mold 22. Thereby, as shown in FIG. 2 (b), the distance a between the die mating surface 22a of the upper die 22 and the die mating surface 21a of the lower die 21, that is, die die matching. The relative distance of the surface can be directly measured by the distance meter 23.

  The shape and the mounting position of the mounting bracket 32 and the target member 34 can be arbitrarily determined. However, in order to directly measure the relative distance of the mold mating surface of the mold, the distance meter 23 and the target member 34 It is desirable that the lower end surface is in a position close to the mold mating surface 21 a of the lower mold 21 and the mold mating surface 22 a of the upper mold 22.

  Moreover, in this Embodiment, the control apparatus 25 for press apparatuses acquires the output signal of the distance meter 23 via the signal wire | line 33a, Based on the said mold matching surface 22a of the upper metal mold | die 22 based on the said output signal, The value of the distance a between the lower mold 21 and the mold mating surface 21a is acquired. In this case, the control device 25 for the press device acquires the output signal of the temperature measuring device 24 via the signal line 33b, and acquires the temperature of the distance meter 23 or the vicinity of the distance meter 23 based on the output signal. . And the control apparatus 25 for press apparatuses calculates the true value of the relative distance of the metal mold | die matching surface of a metal mold | die by correct | amending the value of the said distance a with temperature. The true value is a value obtained by removing the influence of factors such as the temperature change of the output characteristic of the distance meter 23 and the thermal expansion of the mounting bracket 32 and the target member 34 from the measured value of the relative distance. A value that is considered a value.

  And the said control apparatus 25 for press apparatuses performs feedback control of the drive device 17 based on the said truth value, and the relative distance of the metal mold | die matching surface of a metal mold | die at the time of a mold closing and mold clamping is appropriate, The position of the upper mold 22 is controlled. Therefore, it is possible to prevent the upper mold 22 or the lower mold 21 from being damaged, and to reduce the load applied to the upper mold carriage 15 and the driving device 17 that move the upper mold 22 in the vertical direction. Furthermore, since the shape of the cavity space formed by the cavity 21b of the lower mold 21 and the cavity 22b of the upper mold 22 can be accurately reproduced, a high-quality molded product having an accurate outer shape is highly reproducible. Can be molded. For example, the accuracy of the thickness of the molded product can be ± 1.0 [μm] or less. In the mold apparatus according to the present embodiment, the mold mating surface 22a of the upper mold 22 and the mold mating surface 21a of the lower mold 21 are not in contact with each other when the mold is closed and clamped. You may make it contact. The relative distance may be measured for each molding process, for each predetermined number of molding processes, or for a predetermined period or every elapse of a predetermined time.

  Next, temperature correction performed by the control device 25 for the press apparatus will be described.

  FIG. 3 is a diagram showing a relationship between the output of the distance meter and the temperature in the first embodiment of the present invention, and FIG. 4 is a diagram showing the relative distance of the mold mating surface and the distance meter in the first embodiment of the present invention. FIG. 5 is a flowchart showing the temperature correction operation in the first embodiment of the present invention. In FIG. 3, the vertical axis represents the output of the distance meter, the horizontal axis represents the temperature, the vertical axis in FIG. 4 represents the relative distance of the mold mating surface, and the horizontal axis represents the output of the distance meter. It is taken.

  By the way, the characteristics of the distance meter 23 may slightly change depending on the temperature. That is, a temperature-dependent output change may occur in the distance meter 23. Further, the distance meter 23 itself, the mounting bracket 32, the target member 34, the upper mold 22, the lower mold 21, and the like are deformed by thermal expansion, and the distance between the upper end surface of the distance meter 23 and the lower end surface of the target member 34. And the distance a between the mold mating surface 22a of the upper mold 22 and the mold mating surface 21a of the lower mold 21 may change. In such a case, the output of the distance meter 23 changes as the temperature rises, and the distance a between the mold mating surface 22a of the upper mold 22 and the mold mating surface 21a of the lower mold 21 is determined. It becomes impossible to measure accurately.

  In the present embodiment, the press device control device 25 performs temperature correction of the output signal of the distance meter 23 based on the output signal of the temperature measuring device 24. In this case, the control device 25 for the press apparatus acquires the output signal of the distance meter 23, and based on the output signal, the mold mating surface 22a of the upper mold 22 and the mold mating surface 21a of the lower mold 21 The value of the distance a is acquired as the measurement result of the distance meter 23. Moreover, the control device 25 for press apparatuses acquires the output signal of the temperature measuring device 24, and acquires the temperature of the vicinity of the distance meter 23 as a measurement result of the temperature measuring device 24. Then, based on the temperature correction table created in advance, the measurement result of the distance meter 23 is corrected according to the temperature in the vicinity of the distance meter 23.

  Therefore, a method for creating the temperature correction table will be described. In this case, first, a plurality of calibration blocks 26 having different dimensions in the thickness direction are prepared. For example, four calibration blocks 26 having dimensions in the thickness direction of L1, L2, L3, and L4 are prepared. The dimensions L1, L2, L3, and L4 in the thickness direction have a relationship of L1> L2> L3> L4, and each is strictly measured.

  Next, the four calibration blocks 26 are sequentially sandwiched between the upper mold 22 and the lower mold 21 as shown in FIG. Thereby, the relative distance of the mold becomes the predetermined values L1, L2, L3, and L4. Then, by operating a heating means (not shown) and changing the temperatures of the upper mold 22 and the lower mold 21 in the same pattern as when molding a molded product, the output signals of the distance meter 23 and the temperature measuring device 24 are output. collect. Subsequently, when the output of the distance meter 23 is plotted with respect to a change in temperature measured by the temperature measuring device 24 based on the collected output signal, a result as shown in FIG. 3 can be obtained. In FIG. 3, the curve (1) shows the case where the dimension in the thickness direction of the calibration block 26 is L1, and the curve (2) shows the case where the dimension in the thickness direction of the calibration block 26 is L2. (3) shows the case where the dimension in the thickness direction of the calibration block 26 is L3, and curve (4) shows the case where the dimension in the thickness direction of the calibration block 26 is L4.

  When the inventor of the present invention actually experimented using a press device, in the case of the calibration block 26 having the same dimension in the thickness direction, even if the experiment is repeated, a substantially similar curve can be obtained. did it. From this, it can be seen that the temperature correction of the output signal of the distance meter 23 performed based on the output signal of the temperature measuring device 24 is reproducible. Further, since the calibration block 26 made of zero thermal expansion glass was used, it was impossible to find the influence of thermal expansion on the dimension of the calibration block 26 in the thickness direction. The same result can be obtained even when a calibration block 26 is used that combines a material with a positive thermal expansion coefficient and a material with a negative thermal expansion coefficient so that the thermal expansion coefficient is zero. I was able to. Further, when the calibration block 26 made of a normal material having a known thermal expansion coefficient is used, the same result can be obtained if correction is made in consideration of the thermal expansion coefficient. Then, by performing this experiment, it has been found that the output value of the distance meter 23 changes as the temperature changes even if the interval between the molds does not change.

  Subsequently, based on the curves (1) to (4) shown in FIG. 3, the vertical dimension plots the dimension in the thickness direction of the calibration block 26, and the horizontal axis plots the value of the output signal of the distance meter 23. By doing so, a result as shown in FIG. 4 can be obtained. That is, it is possible to obtain a curve indicating the relationship between the dimension in the thickness direction of the calibration block 26 at each temperature measured by the temperature measuring device 24, that is, the relative distance between the mold mating surfaces and the output signal of the distance meter 23. it can. In FIG. 4, a curve (1) shows a case where the temperature measured by the temperature measuring device 24 is T1, a curve (2) shows a case where the temperature measured by the temperature measuring device 24 is T2, and the curve ( 3) shows the case where the temperature measured by the temperature measuring device 24 is T3, and the curve (4) shows the case where the temperature measured by the temperature measuring device 24 is T4. Therefore, based on the relationship between the relative distance between the mold mating surfaces at each temperature as shown in FIG. 4 and the output signal of the distance meter 23, the measurement result of the distance meter 23 depends on the temperature in the vicinity of the distance meter 23. Thus, a temperature correction table for correction can be created. That is, FIG. 4 can be said to be equivalent to the temperature correction table. As described above, the temperature correction table indicates the distance when the temperature of the distance meter 23 or the vicinity of the distance meter 23 is changed in a state where the relative distance of the mold is set to the predetermined values L1, L2, L3, and L4. It is created based on the measured values of the meter 23 and the temperature measuring device 24.

  Note that a large number of calibration blocks 26 each having a small dimensional difference in the thickness direction were prepared, and the output of the distance meter 23 corresponding to a minute change in temperature measured by the temperature measuring device 24 was collected finely. In this case, even if the measurement result of the distance meter 23 is corrected according to the temperature in the vicinity of the distance meter 23 by compensating the data of the section where data is not collected by linear interpolation, a highly accurate correction value is obtained. Obtainable. When the number of data points is small, a highly accurate correction value can be obtained by performing interpolation in consideration of nonlinearity.

  In the present embodiment, a temperature correction table is created based on the relationship between the relative distance of the die mating surfaces at each temperature as shown in FIG. 4 and the output signal of the distance meter 23, and the temperature correction table is pressed. The information is stored in advance in the device control device 25. The press device controller 25 corrects the temperature of the output signal of the distance meter 23 based on the output signal of the temperature measuring device 24. In this case, the press device control device 25 obtains the output signal of the distance meter 23 and also obtains the output signal of the temperature measuring device 24. Since the temperature measuring device 24 is attached to the mounting bracket 32 together with the distance meter 23 at a position close to the distance meter 23, the temperature measuring device 24 detects the temperature of the distance meter 23 or the temperature in the vicinity of the distance meter 23. You can think that you are.

  Subsequently, the control device 25 for the pressing device determines the distance a between the die mating surface 22 a of the upper die 22 and the die mating surface 21 a of the lower die 21 based on the output signal of the distance meter 23. Calculate. Then, the pressing device control device 25 accesses the temperature correction table, corrects the distance a according to the correction value corresponding to the temperature of the distance meter 23, and the positional deviation amount of the distance a after temperature correction. Is calculated. And the said control apparatus 25 for press apparatuses outputs the calculated said distance a as a truth value of the relative distance of the metal mold | die matching surface of a metal mold | die.

  When temperature correction is not performed, even if the distance between the mold mating surface 22a of the upper mold 22 and the mold mating surface 21a of the lower mold 21 is unchanged, the output signal of the distance meter 23 is As shown by the curves (1) to (4) in FIG. As a result, the relationship between the distance between the mold mating surface 22a of the upper mold 22 and the mold mating surface 21a of the lower mold 21 and the output signal of the distance meter 23 is represented by the curves (1) to ( As shown in 4), it varies depending on the temperature. Therefore, by correcting the measurement result of the distance meter 23 according to the temperature near the distance meter 23 based on the temperature correction table equivalent to FIG. The distance a between the mold mating surface 22a and the mold mating surface 21a of the lower mold 21 can be accurately calculated.

  And the said control apparatus 25 for press apparatuses performs feedback control of the drive device 17 based on the said truth value, and the relative distance of the metal mold | die matching surface of a metal mold | die at the time of a mold closing and mold clamping is appropriate, The position of the upper mold 22 is controlled. Therefore, it is possible to prevent the upper mold 22 or the lower mold 21 from being damaged, and to reduce the load applied to the upper mold carriage 15 and the driving device 17 that move the upper mold 22 in the vertical direction. Furthermore, since the shape of the cavity space formed by the cavity 21b of the lower mold 21 and the cavity 22b of the upper mold 22 can be accurately reproduced, a high-quality molded product having an accurate outer shape is highly reproducible. Can be molded.

  The inventor of the present invention creates a temperature correction table based on the relationship between the relative distance of the die mating surfaces at each temperature and the output signal of the distance meter 23 as shown in FIG. 4, and presses the temperature correction table. It was memorize | stored in the control apparatus 25 for apparatuses. Then, the press device is actually used, and the control device 25 for the press device drives the driving device 17 according to the result of correcting the measurement result of the distance meter 23 according to the temperature in the vicinity of the distance meter 23 based on the temperature correction table. The molded product was molded by controlling the movement of the mold. And as a result of shape | molding 300 molded articles, it turned out that the standard deviation of the thickness dimension of a molded article is 1.0 [micrometers] or less.

Next, a flowchart will be described.
Step S1 The control device 25 for the press device acquires the output signal of the distance meter 23.
Step S2 The pressing device control device 25 acquires the output signal of the temperature measuring device 24.
Step S3 The control device 25 for the press device corrects the distance a corresponding to the temperature based on the temperature correction table, and calculates the distance a after temperature correction.
Step S4 The control device 25 for the press device outputs the distance a after the temperature correction, and ends the process.

  Thus, in the present embodiment, the lower end surfaces of the distance meter 23 and the target member 34 are arranged at positions close to the mold mating surface 21 a of the lower mold 21 and the mold mating surface 22 a of the upper mold 22. The relative distance of the mold mating surface of the mold is directly measured by the distance meter 23. Based on the temperature correction table prepared in advance, the measurement result of the distance meter 23 is corrected according to the temperature measured by the temperature measuring device 24 disposed in the vicinity of the distance meter 23. Yes.

  Therefore, the relative distance of the mold mating surface of the mold can be accurately measured with high accuracy, and the accuracy of the thickness dimension of the molded product can be greatly improved by controlling the relative distance according to the measurement result. Can do.

  Further, since the measurement result of the distance meter 23 is corrected by the temperature correction table created based on the result of measurement using the calibration block 26, the distance meter 23, and the temperature measuring device 24, the mounting bracket 32, the target member 34, and the like. Even if the coefficients of thermal expansion of the members such as the upper mold 22 and the lower mold 21 are not known, the measurement result of the distance meter 23 can be accurately temperature-corrected. Therefore, there is no need to estimate the amount of thermal expansion of the member, and the reliability of the relative distance of the measured mold mating surface of the mold is improved.

  In addition, the relative distance of the mold mating surface of the mold can be accurately measured with high accuracy without processing the mold mating surface of the mold with high accuracy, thereby reducing the cost of the mold. be able to. Furthermore, since the relative distance between the mold mating surfaces can be kept constant without physically contacting the upper mold 22 and the lower mold 21, the life of the mold can be extended. Furthermore, a molded product having the same dimensions can be stably molded, and the time for adjusting the operating conditions of the press apparatus 10 can be shortened.

  Next, a second embodiment of the present invention will be described. In addition, about what has the same structure as 1st Embodiment, the description is abbreviate | omitted by providing the same code | symbol. The description of the same operation and the same effect as those of the first embodiment is also omitted.

  FIG. 6 is a view showing a mold apparatus to which a distance meter, a temperature measuring device, and a target member are attached according to the second embodiment of the present invention. 6A is a front view of the mold apparatus, FIG. 6B is a view taken in the direction of arrow D in FIG. 6A, a side view of the mold apparatus, and FIG. 6C is FIG. It is a figure seen from the arrow E of FIG.

  In the present embodiment, the distance meter 23 and the temperature measuring device 24 are attached to the side surface of the lower mold 21 via the attachment bracket 41 as shown in FIG. The mounting bracket 41 has a rectangular parallelepiped shape as a whole, and is attached to a side surface near the upper end of the lower mold 21 by a fixing member such as a bolt. A distance meter 23 and a temperature measuring device 24 are attached to the upper end surface of the mounting bracket 41 so as to be embedded. The upper end surface of the mounting bracket 41 is parallel to the mold mating surface 21 a of the lower mold 21.

  A target member 42 is attached to the side surface of the upper mold 22. The target member 42 has substantially the same shape as the mounting bracket 41 and is attached to a side surface near the lower end of the upper mold 22 by a fixing member such as a bolt. The lower end surface of the target member 42 is parallel to the mold mating surface 22 a of the upper mold 22.

  The distance meter 23 is attached so that the upper end surface, which is the measurement surface, is at a position that is the same as or slightly lower than the mold mating surface 21 a of the lower mold 21. The target member 42 is attached so that the lower end surface thereof is at the same position as or slightly higher than the mold mating surface 22 a of the upper mold 22. As a result, as shown in FIG. 6B, the distance a between the die mating surface 22a of the upper die 22 and the die mating surface 21a of the lower die 21, that is, die die matching. The relative distance of the surface can be directly measured by the distance meter 23. Since other points are the same as those in the first embodiment, description thereof is omitted.

  Thus, in the present embodiment, the distance meter 23 is attached to the side surface of the lower mold 21 via the mounting bracket 41, and the target member 42 is directly attached to the side surface of the upper mold 22. Then, the relative distance of the mold mating surface of the mold is directly measured by the distance meter 23. Therefore, the relative distance of the mold mating surface of the mold can be accurately measured with higher accuracy, and the accuracy of the thickness dimension of the molded product is greatly improved by controlling the relative distance according to the measurement result. be able to.

  Incidentally, in the first and second embodiments, the example in which the distance meter 23 and the temperature measuring device 24 are attached to the lower mold 21 has been described, but the distance meter 23 and the temperature measuring device 24 are the upper ones. It may be attached to the mold 22. Further, the lower mold 21 can be moved in the vertical direction. Further, in the first and second embodiments, the vertical type pressing device in which the upper mold 22 moves in the vertical direction (vertical direction) has been described. However, the upper mold 22 or the lower mold 21 is in the horizontal direction. The present invention can also be applied to a horizontal type pressing device that moves in a direction (horizontal direction). Furthermore, the present invention can be applied not only to a pressing apparatus in which only one of the upper mold 22 or the lower mold 21 is moved, but also to a pressing apparatus in which both the upper mold 22 and the lower mold 21 are moved.

  Furthermore, in the present embodiment, the case of molding a molded product made of glass has been described. However, in the molding of a molded product made of a material such as glass or resin, the material is heated immediately before molding, There is a case where it is placed in an atmosphere, for example, an inert gas atmosphere, or the molded product is cooled immediately after molding. In such a case, a heating device, a cooling device, an inert gas supply device, and the like can be disposed around the press device 10. As a result, the raw material or molded product is directly heated or cooled in an inert gas atmosphere, placed on the lower mold 21, or between the upper mold 22 and the lower mold 21. It becomes possible to heat or cool a material or a molded product sandwiched in the formed cavity space.

  In addition, this invention is not limited to the said embodiment, It can change variously based on the meaning of this invention, and does not exclude them from the scope of the present invention.

It is the schematic which shows the structure of the press apparatus in the 1st Embodiment of this invention. It is a figure which shows the metal mold | die apparatus with which the distance meter in the 1st Embodiment of this invention, the temperature measuring device, and the target member were attached. It is a figure which shows the relationship between the output of the distance meter and temperature in the 1st Embodiment of this invention. It is a figure which shows the relationship between the relative distance of the metal mold | die matching surface in the 1st Embodiment of this invention, and the output of a distance meter. It is a flowchart which shows the operation | movement of the temperature correction in the 1st Embodiment of this invention. It is a figure which shows the metal mold | die apparatus with which the distance meter in the 2nd Embodiment of this invention, the temperature measuring device, and the target member were attached.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Press apparatus 23 Distance meter 24 Temperature measuring device 25 Press means control means 26 Calibration block

Claims (9)

(A) a pair of molds;
(B) a distance measuring means for measuring a relative distance between the molds;
(C) a temperature measuring means for measuring the temperature of the distance measurement hand stage,
(D) A molding apparatus comprising correction means for correcting the relative distance between the molds measured by the distance measurement means according to the temperature measured by the temperature measurement means. Said correction means, said distance measuring means and temperature temperature created based on the measurement values of the measuring means when in a state where the relative distance between the die and the predetermined value is varied the temperature of said distance measuring hand stage The molding apparatus according to claim 1, wherein the relative distance between the molds measured by the distance measuring unit is corrected by a correction table. The molding apparatus according to claim 2, wherein the relative distance between the molds is set to a predetermined value by sandwiching a calibration block between the molds. The molding apparatus according to claim 1, wherein the distance measuring unit measures a displacement between the molds. It said distance measuring means and temperature measuring means, The apparatus according to any one of claims 1 to 4 which is disposed one or the other of the mold. The molded product shape | molded by the shaping | molding apparatus of any one of Claims 1-5. (A) a step of measuring a relative distance between the pair of molds by a distance measuring means;
(B) temperature measuring means, a step of measuring the temperature of said distance measuring hand stage,
(C) The correction means includes a step of correcting the relative distance between the molds measured by the distance measurement means in accordance with the temperature measured by the temperature measurement means. . Said correction means, said distance measuring means and temperature temperature created based on the measurement values of the measuring means when in a state where the relative distance between the die and the predetermined value is varied the temperature of said distance measuring hand stage The mold relative distance measuring method according to claim 7, wherein a relative distance between the molds measured by the distance measuring unit is corrected by a correction table. The mold relative distance measuring method according to claim 8, wherein the relative distance between the molds is set to a predetermined value by sandwiching a calibration block between the molds.

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