JP2015193502A - Optical glass element manufacturing apparatus and manufacturing method using hydraulic press apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To optimize the timing of a press molding operation of a glass material by a hydraulic press apparatus.SOLUTION: In a technique for pressing a glass material by a hydraulic pressure driven press shaft 10 thereby to manufacture an optical glass element, a flow control valve 27 for a hydraulic actuator is operated for every predetermined time period on the basis of the position or the velocity of a press shaft 10 and the pressure of the working oil to be fed to a hydraulic actuator 20, thereby to provide an optical glass element manufacturing apparatus 1 having a method for precisely controlling the position and velocity of the press shaft 10 at the individual points of time of press working steps thereby to optimize the timing for press-molding the glass material.

Description

  The present invention relates to an apparatus and a method for manufacturing an optical glass element using a hydraulic press apparatus.

  For example, press molding is widely used to manufacture specially shaped optical glass elements such as aspherical lenses. An optical glass element manufacturing apparatus using press molding generally controls a press apparatus for pressing a mold on which a glass material is set, a press control apparatus for controlling the press apparatus, and a temperature of the mold. A heater system is provided.

  In a press molding process in which a glass material is press-molded with a press shaft, for example, it is necessary to control the press molding operation with the press shaft with high accuracy under the condition that the glass material is controlled at a constant temperature.

  The press apparatus used for press molding of glass material includes a mechanical press apparatus, typically an electric servo press apparatus driven by an electric servo motor, and a hydraulic press apparatus, typically a hydraulic actuator. There are two types of hydraulic press devices.

  Since the electric servo press device is relatively easy to control the position and speed of the press shaft relatively easily, the electric servo press device is advantageous to satisfy the above control requirements. On the other hand, since the mechanism for driving the press shaft of the hydraulic press apparatus can be made smaller than the electric servo press apparatus, it may be preferable to employ the hydraulic press apparatus.

  For example, a compact press machine is designed that allows multiple press shafts for driving multiple molds to be arranged close to each other, thereby pressing multiple glass materials in parallel. This is the case.

  An optical glass element manufacturing apparatus using a hydraulic press device is disclosed in, for example, Patent Document 1 (Japanese Patent Laid-Open No. 11-180720) and Patent Document 2 (Japanese Patent Laid-Open No. 2004-203686). Patent Document 1 (Japanese Patent Laid-Open No. 11-180720) discloses a technique for changing the pressing force of a cylinder of a press device while a mold driven by a hydraulic press device is pressing a glass material. ing.

  Further, for example, in Patent Document 2 (Japanese Patent Application Laid-Open No. 2004-203686), when a mold driven by a hydraulic press device starts pressing a glass material, hydraulic oil of a predetermined flow rate is supplied to a hydraulic cylinder of the press device. A technique for switching between an operation of supplying hydraulic oil and an operation of supplying hydraulic oil of a predetermined pressure is disclosed.

JP-A-11-180720 JP 2004-203686 A

  As described above, in the press forming of a glass material, it is necessary to control the press forming operation by the press shaft with high accuracy. However, in the case of the hydraulic press device, the relationship between the flow rate of the hydraulic oil flowing into the hydraulic actuator and the operation signal value of the proportional valve for obtaining the flow rate changes according to the pressure of the hydraulic oil.

  Therefore, it is not easy to accurately control the speed or position of the press shaft while the press shaft is being driven.

  For example, in the case of a hydraulic press apparatus, there may occur a case where the time when the press forming operation by the press shaft starts, changes or ends is too early or too late than the optimum time. In the case of a hydraulic press apparatus, when a plurality of molds as described above are driven simultaneously by a plurality of hydraulic press shafts, the timing of press molding operations of all the molds can be made to coincide with each other. difficult. As a result, the quality or variation of the manufactured optical glass element may be caused.

  Therefore, an object of the present invention is to optimize the timing of the glass material press-forming operation by the hydraulic press device.

  Another object of the present invention is to match the timings of the press molding operations of all the molds when driving a plurality of molds with a plurality of hydraulic press shafts.

  One embodiment of the present invention is an apparatus for manufacturing an optical glass element by press-molding a glass material with a press shaft driven by a hydraulic actuator. The manufacturing apparatus includes a flow rate control valve for controlling the flow rate of hydraulic oil of the hydraulic actuator, a position sensor that senses the position of the press shaft, and a press control device. The press control device controls the flow rate control valve based on a signal from the position sensor every predetermined time.

  The manufacturing apparatus may include a plurality of press shafts respectively driven by separate hydraulic actuators, and may be configured to press a plurality of glass materials in parallel. A position sensor can be provided for each press axis. The press control device may be configured to control each corresponding flow rate control valve based on a signal from each position sensor at predetermined time intervals.

  According to one embodiment of the present invention, the position or speed of the press shaft at each point in time while the press shaft is driven can be grasped by a signal from the position sensor. The timing of the press molding operation can be controlled based on the grasped position or speed of the press shaft.

  Further, in the case of a manufacturing apparatus that presses a plurality of molds in parallel with a plurality of press shafts, it becomes easier to match the timings of the press molding operations of the plurality of molds.

FIG. 1 is a schematic diagram for explaining a main part (press working device) of an optical glass element manufacturing apparatus 1 according to an embodiment of the present invention. FIG. 2 shows an example of the temperature control process and the press working process in the manufacturing process of the optical glass element. FIG. 3 is a block diagram for explaining an example of the configuration of an apparatus for controlling the speed of each press shaft 10. FIG. 4 is a time chart showing an example of the pressure applied by the hydraulic cylinder 20 to the press shaft 10 and the change in the position (target speed) of the press shaft 10 when the press shaft 10 is lowered. FIG. 5 is a diagram illustrating an example of function information that defines a voltage command value to the flow control valve 27 as a function of the hydraulic value of the hydraulic cylinder 20 and the speed value of the press shaft 10. FIG. 6 is a flowchart showing an example of the flow of control processing of the speed-voltage calculation program 43. FIG. 7 is a flowchart showing an example of the processing flow of the speed monitoring program 500, which is a subprogram of the speed-voltage calculation program 43, and the actual pressure monitoring program 510. FIG. 8 is a block diagram showing a configuration of a modified example of the apparatus for controlling the press speed of each press shaft 10. FIG. 9 is a flowchart showing an example of the processing flow of the speed-voltage calculation program 43 and the pressure-voltage calculation program 51 in the modification shown in FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the embodiments described below do not limit the invention according to the claims, and all combinations of features described in the embodiments are not necessarily essential to the solution means of the invention. Absent. In addition, the same code | symbol is attached | subjected to the part which can be judged to be the same or the same part in a figure, and the description is not repeated.

  FIG. 1 is a schematic diagram for explaining a main part (press working device) of an optical glass element manufacturing apparatus 1 according to an embodiment of the present invention.

  The optical glass element manufacturing apparatus 1 according to the present embodiment includes a plurality of press shafts 10 for pressing in parallel a plurality of molds 31 each having a glass material set therein. In addition, the manufacturing apparatus 1 includes a common furnace 30 for heating a plurality of molds 31 in parallel and controlling the temperatures thereof. In the manufacturing apparatus 1 shown in FIG. 1, the number of the press shafts 10 is four. However, this is merely an example, and the number of the press shafts 10 may be one or plural other than four. Good.

  The plurality of press shafts 10 are driven by individual hydraulic cylinders (hydraulic actuators) 20. A pressure switching valve 25, a direction switching valve 26, and a flow control valve 27 are provided for each hydraulic cylinder 20. The hydraulic oil is supplied to each hydraulic cylinder 20 from a common hydraulic pump 28 through each pressure switching valve 25, each direction switching valve 26 and each flow control valve 27 in order.

  A common press control device 40 controls each pressure switching valve 25, each direction switching valve 26, and each flow control valve 27. Thereby, switching of the pressure of the hydraulic oil supplied to each hydraulic cylinder 20 (for example, switching between two stages of high pressure and low pressure), switching of the direction (up and down of each press shaft 10), and each hydraulic cylinder 20 The flow rate of the supplied hydraulic oil is adjusted. In the manufacturing apparatus 1 shown in the figure, a common press control device 40 is provided for the plurality of press shafts 10, but a dedicated press control device 40 may be provided for each press shaft 10.

  Each hydraulic cylinder 20 is provided with a pressure sensor 21 that outputs a pressure sensor signal in response to the pressure of hydraulic oil supplied to each hydraulic cylinder 20. Furthermore, each hydraulic cylinder 20 is provided with a position sensor 22 that outputs a position sensor signal in response to the position of each press shaft 10 in the movement (up / down) direction. The pressure sensor signal from each pressure sensor 21 and the position sensor signal from each position sensor 22 are input to the press control device 40.

The tip of each press shaft 10 is inserted into a furnace 30, and a press head 11 for pressing the upper part of each mold 31 uniformly is provided there. A base (base part) 34 is installed on the floor in the furnace 30, and a support base 33 is installed on the base 34. On the support base 33,
A plurality of mold support members 32 are installed. A molding die 31 is provided on each die support member 32, and the molding die 31 faces the press shaft 10.

  Although not shown, each mold 31 is composed of a combination of a sleep and an upper mold and a lower mold that are inserted into a sleeve and in which a glass material is set.

  The furnace 30 surrounds a press working space including a plurality of mold support members 32, a plurality of molds 31, and a plurality of press heads 11. A temperature control device (not shown) controls the heating power of the furnace 30 to control the temperatures of the plurality of molds 31 to the optimum temperature as uniform as possible in each step.

  FIG. 2 shows an example of the temperature control process and the press working process in the manufacturing process of the optical glass element.

  In the example shown in FIG. 2, the manufacturing apparatus 1 includes a heating chamber, a soaking chamber, a first press chamber, a first annealing chamber, a holding chamber, a second pressing chamber, and a second annealing chamber that are serially arranged. A quenching chamber and an exchange chamber. Press working apparatuses having the structure shown in FIG. 1 are installed in the first and second press chambers, respectively.

  In this manufacturing process, a plurality of molds 31 on which the glass material shown in FIG. 1 is set are transferred in parallel to these chambers. The temperature change curve in the figure shows the temperature change of the mold 31 (specifically, the upper surface of the mold support member 32 facing the mold 31).

  First, the plurality of molds 31 enter the heating chamber, where they are rapidly heated to a temperature in the vicinity of the yield point (deflection temperature) Ts of the glass material. Next, the plurality of molds 31 move to a soaking chamber, where they are held for a while at a temperature near the yield temperature Ts.

  Next, the plurality of molds 31 move to the first press chamber, where they are set in a first press working apparatus having the structure shown in FIG. 1, and the first press work P1 is performed. At this time, the plurality of molds 31 are maintained at a temperature near the yield temperature Ts. Next, the plurality of molds 31 are moved to the first annealing chamber, where the plurality of molds 31 are cooled to a temperature slightly higher than the glass transition point (transition temperature) Tg of the glass material.

  Next, the plurality of molds 31 move to the holding chamber, where they are held for a while at a temperature slightly higher than the transition temperature Tg. Next, the plurality of molds 31 are moved to the second press chamber, where they are set in a second press processing apparatus having the structure shown in FIG. 1, and the second press processing P2 is performed. At this time, the plurality of molds 31 are cooled at a predetermined temperature decrease rate. Thereafter, the plurality of molds 31 are cooled while being transferred to the second annealing chamber, the quenching chamber, and the exchange chamber.

  As a modified embodiment, all of the temperature control process and the press working process shown in FIG. 2 may be performed by one press working apparatus having the structure shown in FIG.

  In the above steps, molding is performed in the first press chamber (first press processing P1) under the condition that the mold 31 is controlled at a constant temperature, and in the second press chamber (second press processing P2). It is necessary to control the press forming operation by the press shaft 10 with high accuracy under the condition that the mold 31 is controlled by a constant temperature change curve. A detailed control method of each press shaft 10 by the press control device 40 for realizing this will be described below.

  FIG. 3 is a block diagram for explaining an example of the configuration of an apparatus for controlling each press shaft 10.

  In FIG. 3, only the configuration of the apparatus for controlling one press shaft 10 is representatively described, but the configuration for controlling the other press shaft 10 is the same as that.

  The press control device 40 includes a CPU 41 and a memory 42. The memory 42 stores various programs for controlling the operation of the press shaft 10. The CPU 41 executes those programs. As a result, the press control device 40 issues a pressure switching command for switching the pressure switching valve 25, a direction switching command for switching the direction switching valve 26, and a voltage command for controlling the opening degree of the flow control valve 27. Output.

  Among these commands, the voltage command for controlling the opening degree of the flow control valve 27 is directly related to the control of the timing of the press working operation. The following description focuses on the configuration related to the voltage command.

  The memory 42 of the press control device 40 stores a speed-voltage calculation program 43 for creating a voltage command value for the flow control valve 27. When the CPU 41 executes the speed-voltage calculation program 43, the press control apparatus 40 performs the following operations at predetermined short time intervals (for example, 0.5 second intervals) that can be regarded as being substantially continuous.

  That is, the press control device 40 inputs the pressure sensor signal from the pressure sensor 21 of the hydraulic cylinder 20 and the position sensor signal from the position sensor 22 at predetermined short time intervals. The values of these input signals are stored in the memory 42.

  The press control device 40 (speed-voltage calculation program 43) matches the current speed of the press shaft 10 with a predetermined target speed based on the values of the pressure sensor signal and the position sensor signal stored in the memory 42. Voltage command value (operation amount for the press shaft 10) is generated. Details of this processing will be described later.

  The press control device 40 (speed-voltage calculation program 43) outputs the generated voltage command value to the voltage-current converter 24. The voltage-current converter 24 adjusts the magnitude of the current flowing through the flow control valve 27 to a value corresponding to the voltage command value.

  As a result, the opening degree of the flow control valve 27 is controlled to a value corresponding to the voltage command value, and the flow rate of the hydraulic oil flowing through the hydraulic cylinder 20 is controlled. As a result, the speed of the press shaft 10 becomes a predetermined target speed. Be controlled.

  The press control device 40 makes the positions of the plurality of press shafts 10 coincide with the initial positions of the same height as a preparation step before starting to drive the plurality of press shafts 10. After this initial alignment, the press control device 40 simultaneously starts speed control based on the speed-voltage calculation program 43 for the plurality of press shafts 10 (that is, starts driving the plurality of press shafts 10 at the same time), And those speed control is performed in parallel.

  As a result, at each point in the pressing process, all of the plurality of press shafts 10 move at an optimal position at an optimal speed and without shifting between each other. Therefore, the timing of all pressing operations of the plurality of molds 31 is optimized.

  FIG. 4 is a time chart showing an example of changes in the pressing force applied by the hydraulic cylinder 20 to the press shaft 10 and the position (target speed) of the press shaft 10 when the press shaft 10 is lowered.

  Here, the target speed (V1 to V3) at each time point of the press shaft 10 is indicated by the slope of the curve 71 at each time point. Further, the position of the press shaft 10 when the press shaft 10 moves at the target speed is indicated by a curve 71. A pressing force applied to the press shaft 10 is indicated by a curve 72.

  The target speed may be a predetermined value for each time point stored in advance in the memory 42, or may be a value that is dynamically calculated by the press control device 40 at each time point. .

  <In time interval (t0 to t1)>

  The press control device 40 starts the press shaft 10 to descend at time t0. In the first time interval (t0 to t1), the press control device 40 sets the highest target speed V1 in order to make the press shaft 10 approach the mold 31 quickly.

  The press control device 40 (speed-voltage calculation program 43) calculates a voltage command value so as to lower the press shaft 10 at the highest target speed V1. As a result, a pressing force as shown by a curve 72 is applied to the press shaft 10.

  <In time interval (t1-t2)>

  The press control device 40 sets a target speed V2 lower than the target speed V1 in a time section (t1 to t2) in which the press shaft 10 is close to the mold 31 to some extent. As a result, the pressing force applied to the press shaft 10 decreases.

  <At time t2 to t3>

  The press control device 40 sets the lowest target speed V3 during the time (t2-t3) when the press shaft 10 contacts and presses the mold 31. As the pressing progresses, the pressing force applied to the press shaft 10 increases.

  When the position of the press shaft 10 reaches the cut-off position (a position where the press shaft 10 cannot be lowered any further) at time t3, the speed of the press shaft 10 is automatically zero. The pressing force of the press shaft 10 becomes the maximum pressure determined by the opening degree of the pressure switching valve 25. In the final stage of the pressing step (pressing step), the pressing force may be increased (dotted curve) or decreased (broken line curve) by switching the pressure switching valve 25.

  FIG. 5 is a diagram illustrating an example of function information that defines a voltage command value to the flow control valve 27 as a function of the hydraulic value of the hydraulic cylinder 20 and the speed value of the press shaft 10.

  The function information shown in FIG. 5 is stored in the memory 42 of the press control device 40 in the form of a lookup table, for example. As will be described later, the speed-voltage calculation program 43 refers to this function information. Specific function information may be prepared for each press shaft 10, or common function information may be prepared for a plurality of press shafts 10.

  This function information defines what value the voltage command value to the flow control valve 27 should be in order to move the press shaft 10 at a certain speed value. What is important here is that the flow rate of the hydraulic oil flowing through the flow control valve 27 (that is, the speed of the press shaft 10) varies depending on the pressure value of the hydraulic oil.

  Therefore, in the function information shown in FIG. 5, for each pressure value, the voltage command value (%) is a speed value (mm / sec), for example, linear (may be non-linear) functions 60-1, 60-2, ..., defined as 60-n. For example, the function 60-1 with the steepest slope in FIG. 5 corresponds to the highest pressure value, and the function 60-n with the slowest slope corresponds to the lowest pressure value.

  When attempting to drive the press shaft 10 at a predetermined target speed, the speed-voltage calculation program 43 grasps the current hydraulic pressure value of the corresponding hydraulic cylinder 20 from the pressure sensor signal corresponding to the press shaft 10. Then, the grasped current hydraulic pressure value is applied as the pressure value of the function information, and the target speed is applied as the speed value of the function information.

  As a result, the speed-voltage calculation program 43 receives the voltage command value for driving the press shaft 10 at the target speed under the current hydraulic pressure value as the output of the function information. Furthermore, the speed-voltage calculation program 43 determines a more appropriate voltage command value by adjusting the voltage command value received from the function information in accordance with the target speed and the actual speed of the press shaft 10.

  Hereinafter, the control process of the speed-voltage calculation program 43 will be described more specifically.

  FIG. 6 is a flowchart showing an example of the flow of control processing of the speed-voltage calculation program 43. FIG. 7 is a flowchart showing an example of the processing flow of the speed monitoring program 500, which is a subprogram of the speed-voltage calculation program 43, and the actual pressure monitoring program 510.

  The processing of the speed monitoring program 500 and the actual pressure monitoring program 510 will be described with reference to FIG. The speed monitoring program 500 and the actual pressure monitoring program 510 are stored in the memory 42.

  The speed monitoring program 500 inputs a position sensor signal from the position sensor 22 attached to the hydraulic cylinder 20 at a predetermined time interval (for example, 0.5 second interval) while driving the press shaft 10 ( S501, S502). Next, the speed monitoring program 500 calculates the current actual speed of the press shaft 10 based on the position sensor signals input at the most recent time points (S503). Then, the speed monitoring program 500 stores the calculated actual speed in the memory 42 (S504).

  The actual pressure monitoring program 510 inputs a pressure sensor signal from the pressure sensor 21 attached to the hydraulic cylinder 20 at a predetermined time interval (for example, 0.5 second interval) while driving the press shaft 10. (S511, S512). Then, the actual pressure monitoring program 510 calculates the current actual pressure value of the hydraulic oil in the hydraulic cylinder 20 from the pressure sensor signal, and stores it in the memory 42 (S513).

  The actual speed and the actual pressure value stored in the memory 42 are used in control processing by the speed-voltage calculation program 43 described below.

  Next, the control process by the speed-voltage calculation program 43 will be described with reference to FIG. The control process shown in FIG. 6 is repeatedly executed at predetermined time intervals (for example, 0.5 second intervals).

  The speed-voltage calculation program 43 refers to the current actual pressure value (calculated by the actual pressure monitoring program 510) stored in the memory 42 (S400). The speed-voltage calculation program 43 also determines the current target speed for the press shaft 10 (S401). The target speed value is determined, for example, as described with reference to FIG.

  Thereafter, the speed-voltage calculation program 43 applies the actual pressure value and the target speed to the function information shown in FIG. 5 (S402). As a result, the speed-voltage calculation program 43 obtains a voltage command value for driving the press shaft 10 at the target speed (S403). The voltage command value obtained in S403 is a value that increases or decreases depending on the speed of the press shaft, for example, with this value as an initial value. Therefore, the voltage command value obtained in S403 is not a definitive voltage command value but a “provisional voltage command value”. Hereinafter, this provisional voltage command value is referred to as a first voltage command value.

  Thereafter, the speed-voltage calculation program 43 outputs a voltage command (volt) to the flow control valve 27 based on the first voltage command value (%) obtained in S403 (S404). As a result, the opening degree of the flow control valve 27 is controlled, and the speed of the press shaft 10 is controlled to be the target speed (S405).

  Thereafter, the speed-voltage calculation program 43 refers to a preset pressure limit value stored in advance in the memory 42 (S411). Here, the pressure limit value indicates, for example, the maximum design pressure that may be applied to each press shaft 10.

  Thereafter, the speed-voltage calculation program 43 compares the target speed set in S401 with the latest actual speed (hereinafter, actual speed) stored in the memory 42 (S406). When the actual speed is slower than the target speed (S406: Yes), the press control device 40 compares the actual pressure value with the pressure limit value (S407).

  When the actual pressure value is smaller than the pressure limit value (S407: Yes), the speed-voltage calculation program 43 increases the first voltage command value to match the actual speed with the target speed, and increases the voltage command. A voltage command based on the value is output (S408). The increment of the voltage command value may be a constant value, for example, or may be variably determined according to the magnitude of the difference between the target speed and the actual speed.

  When the actual pressure value is equal to or greater than the pressure limit value (S407: No), the speed-voltage calculation program 43 maintains the current first voltage command value as it is, and returns control to S404.

  On the other hand, when the actual speed is equal to or higher than the target speed (S406: No), the speed-voltage calculation program 43 performs the process of S409. In S409, it is determined whether the actual speed is the same as the target speed or the actual speed is higher than the target speed.

  When the actual speed is higher than the target speed (S409: Yes), the speed-voltage calculation program 43 decreases the first voltage command value to match the actual speed with the target speed, and the reduced voltage command A voltage command value based on the value is output (S410). The decrease amount of the voltage command value may be a constant value, for example, or may be variably determined according to the magnitude of the difference between the target speed and the actual speed.

  When the actual speed is the same as the target speed (S409: No), the speed-voltage calculation program 43 maintains the current first voltage command value as it is, and returns the control to S404.

  The control process described above is performed in parallel using a common target speed for each of the plurality of press shafts 10. As a result, the press working of the plurality of glass materials by the plurality of press shafts 10 is executed at a timing substantially optimized with respect to the temperature control process.

  FIG. 8 is a block diagram showing a configuration of a modified example (partially changed from that shown in FIG. 3) of the device for controlling the speed of each press shaft 10.

  In the modification shown in FIG. 8, instead of the pressure switching valve 25 in FIG. 3, a pressure control valve (for example, an electromagnetic proportional valve) 52 that can adjust the oil pressure steplessly is employed. The press control device 40 further has a pressure-voltage calculation program 51. The press control device 40 executes the pressure-voltage calculation program 51 to control the opening degree of the pressure control valve 52 to finely control the hydraulic pressure applied to the hydraulic cylinder 20.

  Other configurations of this modification are the same as those shown in FIG.

  FIG. 9 shows an example of the flow of processing of the speed-voltage calculation program 43 and the pressure-voltage calculation program 51 in the modification shown in FIG.

  In FIG. 9, S601 to S611 are control processes performed by the speed-voltage calculation program 43, which are substantially the same as S401 to S411 shown in FIG. A description of this control process is omitted.

  In FIG. 9, S621 to S629 are control processes performed by the pressure-voltage calculation program 51. Hereinafter, this control process will be described.

  The pressure-voltage calculation program 51 determines the pressure applied to the press shaft 10 at each time (S621). The pressure applied to the press shaft 10 is determined as described with reference to FIG.

  Next, the pressure-voltage calculation program 51 applies the determined pressure to a pressure table (not shown) (S622). Here, the pressure table indicates function information in which the determined pressure value is associated with the voltage command value necessary for setting the pressure applied to the pressure cylinder to the determined pressure.

  Then, the pressure-voltage calculation program 51 obtains a voltage command value for applying the pressure set to the press shaft 10 (S623). The voltage command value obtained in S623 is a “provisional voltage command value” as in S403. Hereinafter, this temporary voltage command value is referred to as a second voltage command value.

  Thereafter, the pressure-voltage calculation program 51 outputs a voltage command (volt) to the pressure control valve 52 based on the second voltage command value (%) obtained in S623 (S624).

  As a result, the opening degree of the pressure control valve 52 is controlled, and the pressure applied to the press shaft 10 is controlled to be the set pressure (S605).

  Thereafter, the pressure-voltage calculation program 51 compares the pressure limit value with the latest actual pressure (hereinafter, actual pressure value) stored in the memory 42 (S625). When the actual pressure value is lower than the pressure limit value (S625: Yes), the press control device 40 compares the actual speed with the target speed (S626).

  When the actual speed is slower than the target speed (S626: Yes), the pressure-voltage calculation program 51 increases the second voltage command value to match the actual speed with the target speed, and increases the voltage command. A voltage command based on the value is output (S627). The increment of the voltage command value may be a constant value, for example, or may be variably determined according to the magnitude of the difference between the target speed and the actual speed.

  When the actual speed is equal to or higher than the target speed (S626: No), the pressure-voltage calculation program 51 maintains the current second voltage command value as it is, and returns the control to S624.

  On the other hand, when the actual pressure value is equal to or greater than the pressure limit value (S625: No), the pressure-voltage calculation program 51 performs the process of S628. In S628, it is determined whether the actual pressure value is the same as the pressure set in S601 or whether the actual pressure value is higher than the pressure set in S601.

  When the actual pressure value is higher than the set pressure (S628: Yes), the pressure-voltage calculation program 51 decreases the second voltage command value in order to match the actual pressure with the set pressure. A voltage command based on the voltage command value is output (S629). The decrease amount of the voltage command value may be a constant value, for example, or may be variably determined according to the magnitude of the difference between the set pressure and the actual pressure.

  When the actual pressure value is the same as the set pressure (S628: No), the pressure-voltage calculation program 51 maintains the current second voltage command value as it is, and returns the control to S624.

  Finally, embodiments of the present invention will be summarized with reference to the drawings and the like.

  The optical glass element manufacturing apparatus (1) according to the embodiment of the present invention includes a press shaft (10) for pressing a forming die (31) on which a glass material is set, as shown in FIG. A hydraulic actuator (hydraulic cylinder 20) for driving the press shaft (10), a flow rate control valve (27) for controlling the flow rate of hydraulic oil supplied to the hydraulic actuator (hydraulic cylinder 20), and the press shaft A position sensor (22) that outputs a position sensor signal in response to the position of (10); and a press control device (40) that receives the position sensor signal and controls the flow control valve (27). 40) controls the flow rate control valve (27) based on the position sensor signal every predetermined time.

  Preferably, in the optical glass element manufacturing apparatus (1) according to the embodiment of the present invention, the pressure sensor (21) that outputs a pressure sensor signal in response to the pressure of the hydraulic oil supplied to the hydraulic actuator (hydraulic cylinder 20). The press control device (40) controls the flow rate control valve (40) based on the position sensor signal and the pressure sensor signal every predetermined time.

  Furthermore, preferably, in the optical glass element manufacturing apparatus (1) according to the embodiment of the present invention, the press control device (40) determines a target speed of the press shaft (10), and based on the position sensor signal, The actual speed of the press shaft (10) is obtained, and the flow rate control valve (27) is controlled based on the pressure sensor signal, the target speed, and the actual speed every predetermined time.

  Further preferably, in the optical glass element manufacturing apparatus (1) according to the embodiment of the present invention, the press control device (40) controls the flow rate as a function of the pressure value and the velocity value as shown in FIG. The flow control valve (27) has function information that defines the operation amount of the valve (27), and applies the detected pressure value based on the pressure sensor signal as the pressure value and the target speed as the speed value to the function information. 3), the operation amount is adjusted based on the actual speed as shown in FIGS. 3 and 6, and the flow rate control valve (27) is controlled by the adjusted operation amount.

  Furthermore, preferably, in the optical glass element manufacturing apparatus (1) according to the embodiment of the present invention, the press control device (40) has a case where the actual speed is higher than the target speed as shown in FIG. The operation amount is decreased, and when the actual speed is slower than the target speed, the operation amount is increased.

  Further preferably, in the optical glass element manufacturing apparatus (1) according to the embodiment of the present invention, the press control device (40) is supplied to the hydraulic actuator (hydraulic cylinder 20) as shown in FIGS. Control the hydraulic oil pressure.

  In addition, the optical glass element manufacturing apparatus (1) according to the embodiment of the present invention presses a plurality of molds (31) each having a glass material set thereon, as shown in FIG. A plurality of press shafts (10), a plurality of hydraulic actuators (hydraulic cylinders 20) for driving the plurality of press shafts (10), and hydraulic oil supplied to the plurality of hydraulic actuators (hydraulic cylinders 20), respectively. A plurality of flow rate control valves (27) for respectively controlling the flow rates of the plurality of pressure sensors, a plurality of position sensors (22) for outputting position sensor signals in response to the positions of the plurality of press shafts (10), and position sensor signals And press control devices that operate a plurality of flow control valves (27), and the press control device (40) is provided with each position sensor (22) at predetermined time intervals. On the basis of the input position sensor signal, corresponding to control each flow rate control valve (27).

Preferably, in the optical glass element manufacturing apparatus (1) according to the embodiment of the present invention,
The press control device (40) further includes a plurality of pressure sensors (21) that output pressure sensor signals in response to the pressures of hydraulic oil supplied to the plurality of hydraulic actuators (hydraulic cylinders 20). Based on the position sensor signal from (21), the actual speed for each press shaft (10) is obtained, and the pressure sensor signal from each pressure sensor (21) and the actual for each press shaft (10) are obtained at predetermined time intervals. Based on the speed, the corresponding flow control valve (27) is controlled.

  Further, in the method for manufacturing an optical glass element according to the embodiment of the present invention, as shown in FIGS. 3 and 6, the hydraulic pressure of the hydraulic actuator (hydraulic cylinder 20) is sensed, and the actual speed of the press shaft (10). The flow rate control valve (27) for controlling the flow rate of the hydraulic oil supplied to the hydraulic actuator (hydraulic cylinder 20) is controlled at predetermined time intervals based on the sensed hydraulic pressure and the actual speed.

  Preferably, as shown in FIGS. 8 and 9, the hydraulic pressures of a plurality of hydraulic actuators (hydraulic cylinders 20) are sensed, the actual speeds of the plurality of press shafts (10) are grasped, Each flow control valve (27) for controlling the flow rate of hydraulic oil supplied to each hydraulic actuator (hydraulic cylinder 20) based on the hydraulic pressure of the hydraulic actuator (hydraulic cylinder 20) and the actual speed of each press shaft (10). ) To control.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 1 ... Optical glass element manufacturing apparatus 10 ... Upper press shaft 11 ... Press head 20 ... Hydraulic cylinder (hydraulic actuator)
DESCRIPTION OF SYMBOLS 21 ... Temperature sensor 22 ... Position sensor 23 ... Hydraulic piping 25 ... Pressure switching valve 26 ... Direction switching valve 27 ... Flow control valve 28 ... Hydraulic pump 30 ... Furnace 31 ... Mold 32 ... Mold support member 33 ... Mold support stand 34 ... Base 40 ... Press control device

Claims (10)

A press shaft for pressing a mold on which a glass material is set;
A hydraulic actuator for driving the press shaft;
A flow rate control valve for controlling the flow rate of hydraulic oil supplied to the hydraulic actuator;
A position sensor that outputs a position sensor signal in response to the position of the press shaft;
A press control device that receives the position sensor signal and controls the flow rate control valve;
The press control device is an optical glass element manufacturing device that controls the flow rate control valve based on the position sensor signal at predetermined time intervals. A pressure sensor that outputs a pressure sensor signal in response to the pressure of the hydraulic oil supplied to the hydraulic actuator;
2. The optical glass element manufacturing apparatus according to claim 1, wherein the press control device controls the flow rate control valve based on the position sensor signal and the pressure sensor signal at predetermined time intervals. The press control device includes:
Determining the target speed of the press shaft;
Based on the position sensor signal, obtain the actual speed of the press shaft,
The apparatus for manufacturing an optical glass element according to claim 2, wherein the flow rate control valve is controlled at predetermined time intervals based on the pressure sensor signal, the target speed, and the actual speed. The press control device includes:
Having function information defining the manipulated variable of the flow control valve as a function of the pressure value and the speed value;
By applying the pressure detection value based on the pressure sensor signal as the pressure value and the target speed as the speed value to the function information, the operation amount of the flow control valve is obtained,
The optical glass element manufacturing apparatus according to claim 3, wherein the operation amount is adjusted based on the actual speed, and the flow control valve is controlled by the adjusted operation amount. The press control device includes:
If the actual speed is faster than the target speed, decrease the operation amount,
When the actual speed is slower than the target speed, the operation amount is increased.
The apparatus for manufacturing an optical glass element according to claim 4. The optical glass element manufacturing apparatus according to any one of claims 1 to 5, wherein the press control device controls a pressure of hydraulic oil supplied to the hydraulic actuator. A plurality of press shafts for respectively pressing a plurality of molding dies each having a glass material set thereon;
A plurality of hydraulic actuators for respectively driving the plurality of press shafts;
A plurality of flow rate control valves for controlling the flow rates of hydraulic oil respectively supplied to the plurality of hydraulic actuators;
A plurality of position sensors that respectively output position sensor signals in response to the positions of the plurality of press shafts;
A press control device that receives each of the position sensor signals and operates the plurality of flow control valves;
The said press control apparatus is a manufacturing apparatus of the optical glass element which controls each corresponding flow control valve based on the said position sensor signal input from each said position sensor for every predetermined time. A plurality of pressure sensors that output pressure sensor signals in response to pressures of the hydraulic oil supplied to the plurality of hydraulic actuators;
The press control device includes:
Determine a target speed for each press axis;
Based on the position sensor signal from each position sensor, the actual speed for each press axis is obtained,
8. The optical system according to claim 7, wherein each of the corresponding flow rate control valves is controlled based on the pressure sensor signal from each pressure sensor, the target speed, and the actual speed for each press shaft at predetermined time intervals. Glass element manufacturing equipment. In a method of manufacturing an optical glass element by pressing a glass material with a press shaft driven by a hydraulic actuator,
Sense the hydraulic pressure of the hydraulic actuator,
Grasp the actual speed of the press shaft,
An optical glass element manufacturing method for controlling a flow rate control valve for controlling a flow rate of hydraulic fluid supplied to the hydraulic actuator based on the sensed hydraulic pressure and the actual speed every predetermined time. In a method of manufacturing a plurality of optical glass elements by pressing a plurality of glass materials in parallel with a plurality of press shafts respectively driven by separate hydraulic actuators,
Sense the hydraulic pressure of the plurality of hydraulic actuators,
Grasping the actual speed of the plurality of press shafts,
An optical glass element that controls each flow rate control valve for controlling the flow rate of hydraulic fluid supplied to each hydraulic actuator based on the hydraulic pressure of each hydraulic actuator and the actual speed of each press shaft at predetermined time intervals. Manufacturing method.

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