JP4679533B2 - Movable movement control method - Google Patents

Description

  The present invention relates to a movable mold movement control method for a molding machine that molds a movable mold attached to a movable body that is rotated or linearly moved to a fixed mold.

  In the technical field of the present invention, for example, Patent Document 1 is disclosed. The technology of Patent Document 1 includes a fixed platen arranged in a horizontal direction, a movable platen arranged to be movable up and down opposite to the fixed platen, and a vertical drive mechanism that drives the movable platen up and down. A disk-shaped rotary table installed on the lower surface side of the movable plate and moved up and down together with the movable plate and capable of rotating in the forward and reverse directions around the rotation axis, and driving the rotary table in the circumferential direction A plurality of molds including a plurality of lower molds installed on the fixed platen and a plurality of upper molds installed on the rotary table so as to face the lower molds. In a vertical rotary injection molding machine that can be pressed simultaneously at a plurality of rotational positions of the rotary table, a circular driven part with engraved teeth is formed on the outer peripheral surface of the rotary table. A circular drive part is formed by providing a flange part at least on the lower side of the outer peripheral surface, and forming a toothed part on the outer peripheral surface of the drive shaft of the servo motor of the table drive mechanism. The circular drive part and the rotary table A belt or chain member meshing with the tooth portion is stretched between the circular driven portion and the servo motor is controlled to rotate to constantly accelerate up to about half of the predetermined rotation angle of the rotary table, and the remaining substantially The rotary table is rotated by always decelerating half.

  Thus, conventionally, the rotational movement speed, acceleration time, and deceleration time, which are control parameters for mold movement control, are fixedly set so as to be optimal at a standard mold weight. Therefore, when a mold having a weight smaller than that of a standard mold is attached, the rotation time is longer than necessary and the molding cycle time is extended. In addition, when a mold with a weight greater than that of a standard mold is installed, the moment of inertia is large, so it is dangerous to move beyond the stop position, and it takes time for positioning and prolongs the molding cycle time. .

Japanese Patent No. 3363316

  The present invention has been made to solve the above-described problem, and is capable of moving a movable mold of a molding machine that molds a molded product by matching a movable mold attached to a movable body that rotates or moves linearly with a fixed mold. It is an object of the present invention to provide a control method that can be performed quickly and stably regardless of the movable weight.

The present invention provides a movable mold movement control method for a molding machine in which a movable mold attached to a rotating disk rotated with respect to the movable disk is matched with a fixed mold to form a molded product, and the movable mold is used as the rotating disk . the weight of the movable die in a mounted state is detected with the weight of the rotating disk of the weight or the movable platen and turntable, the rotational driving by the rotary drive of the turntable in accordance with the size of the movable mold weight detected The present invention relates to a movable movement control method for a molding machine, characterized by switching control parameters of a control device to be controlled.

According to the movable mold movement control method of a molding machine for forming a molded product by matching a movable mold attached to a rotating disk rotated with respect to the movable disk of the present invention into a fixed mold, the movable mold movement is changed to the movable mold weight. It can be done quickly and stably regardless of the situation.

  Embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a configuration diagram showing an outline of a molding machine that implements the movable movement control method of the present invention. FIG. 2 is a list showing examples of control parameter conversion.

  The molding machine 1 includes a stationary platen 2 that also serves as a gantry, fixed molds 3 and 4 disposed on the upper surface of the stationary platen 2, movable molds 5 and 6 that are alternately aligned with the stationary molds 3 and 4, and movable Mounted with the molds 5 and 6 is a rotating plate 7 which is rotatably provided on the lower surface of the movable platen 8, a movable platen 8 which can be moved up and down so as to be close to and away from the fixed platen 2, and a position detector 20 which detects the position of the movable platen 8. A rotary drive device 9 provided on the upper surface of the movable platen 8 for rotationally driving the rotary platen 7, and fixed molds 3, 4 and the movable die 5 provided above the movable platen 8 via the movable platen 8 and the rotary platen 7. , 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6 Pressure detectors 21 and 22 for detecting the hydraulic pressure of the mold opening chambers 12 and 13 and the operation of the movable platen 8 for clamping and lifting And a control unit 14 for controlling the like.

  As described above, the molding machine 1 injects molten material from a plurality of injection devices (not shown) into two cavities formed between the fixed molds 3 and 4 and the movable molds 5 and 6 to fill the individual cavities. Thereafter, the rotating disk 7 is rotated 180 degrees to change the mold matching between the fixed molds 3 and 4 and the movable molds 5 and 6 to form a molded product. As a result, a molded product is taken out from the cavity of one fixed mold, and a semi-molded product made of some molten material remains in the cavity of the other fixed mold.

  As the rotation drive device 9, an induction motor or a servo motor by inverter control is effectively employed. Since these drive units can generate drive force at a variable speed, during the acceleration time from start-up to constant speed rotation and during the deceleration time from constant speed rotation to stop, it is linear over time. Alternatively, it is variably controlled based on a signal that changes in a curve. The rotation drive device 9 has its drive shaft connected to the shaft provided at the center of the turntable 7, but a belt may be stretched between the outer peripheral surface of the turntable and the drive shaft of the rotation drive device. . In any case, the movable molds 5 and 6 disposed on the rotating disk 7 as a moving body are rotationally driven by the rotational driving device 9.

  The movable platen 8 is moved up and down by the mold opening / closing devices 12 and 13 together with the rotary plate 7 and the movable molds 5 and 6. The moving bodies at this time are the movable platen 8, the rotary platen 7, and the movable molds 5 and 6. The lowering speed of the movable body is determined by the amount of pressure oil discharged from the mold opening chamber 15 defined by the piston 16 of a hydraulic cylinder device suitable as the mold opening / closing devices 12 and 13 and / or the pressure oil supplied to the mold closing chamber 17. The amount is controlled by adjusting with an electromagnetic flow rate adjusting valve or servo valve. That is, in order to shorten the operation time, it is lowered at a high speed to the deceleration position immediately before the mold matching, and thereafter lowered at a low speed.

  After the movable dies 5 and 6 are matched to the fixed dies 3 and 4 and are brought into close contact with each other, high pressure pressure oil is supplied to the pressure chamber 19 defined by the piston 18 of a hydraulic cylinder device suitable as the mold clamping driving devices 10 and 11. Then press the mold. Then, the molten material is injected into the cavity from an injection device (not shown) that contacts the parting surface of the mold. When the molten material in the cavity is cooled and solidified, pressure oil is supplied to the mold opening chamber 15 to raise the moving body. From the mold contact position to the acceleration position and from the deceleration position to the mold opening stop position, it rises at a low speed and from the acceleration position to the deceleration position rises at a high speed. Note that the mold opening / closing devices 12 and 13 may be constituted by servo motors instead of hydraulic cylinder devices. The present invention can also be applied to raising and lowering a movable plate of a general molding machine that does not have a rotating plate, and the movable body at that time is a movable plate and a movable type.

  By the way, there are many types of movable molds 5 and 6 depending on the type of the molded product, and the weight is distributed over a wide range. Therefore, as shown in FIG. 2, a list of control parameter sets that can be selected according to the movable weight is stored in the storage unit of the control device 14. The control parameters are moving speed, acceleration time (position) and deceleration time (position). If the rotary drive device 9 and the mold opening / closing devices 12 and 13 are controlled in a closed loop, the control parameters may include the PID constants. Good. Moreover, the driving force (pressure) setting value of the rotary drive device 9 or the mold opening / closing devices 12 and 13 may be included. The control parameter set includes N (normal) suitable for a standard weight movable type, H (heavy) suitable for a relatively heavy movable type, and L (light) suitable for a relatively small movable type. ), But the number may be increased as necessary. The numerical value of the control parameter may be an absolute value of each parameter, but it is advantageous in terms of easy setting that it is a percentage with respect to each parameter numerical value. When the parameter numerical value is set as a percentage, when the control parameter set is instructed to be selected by INDEX, the control device 14 replaces the parameter value input and set in advance with the percentage of this table. The selection of INDEX is made by the control device 14 and can be set by manual operation, or can be automatically performed by measuring the movable weight as described below.

  Next, a method for measuring the movable weight will be described. The control mode of the control device 14 is switched to movable weight measurement. The movable platen 8 is opened by the mold opening / closing devices 12 and 13 and is stopped and held at a predetermined mold opening position. At this time, the pressure oil in the mold opening chambers 15 of the mold opening and closing devices 12 and 13 is sealed by switching the switching valve of the control device 14 and is closed, and the load force according to the weight of the moving body As a result, hydraulic pressure is generated. The hydraulic pressure value is detected by the pressure detectors 21 and 22 and transmitted to the control device 14. The control device 14 stores the detected hydraulic pressure value after waiting for several tens of seconds until the detected hydraulic pressure value is stabilized, and is obtained by multiplying the preset area value of the piston 16 in the mold opening 15 by the stored hydraulic pressure value. The suspension forces of the mold opening / closing devices 12 and 13 are summed up to calculate and calculate the weight of the moving body. And the control apparatus 14 calculates | requires the weight of the movable mold | types 5 and 6 by subtracting the weight of the movable board 8 and / or the rotary disk 7 which were preset to the control apparatus 14 from the weight of a moving body. When the mold opening / closing device is a servo motor, the load force is detected by the current value of the servo motor. Furthermore, since the detected hydraulic pressure value stored in the control device 14 is a value when the molding machine 1 is normal, the mold opening is completed after the control mode is switched from the movable mold weight measurement to the normal molding state. By comparing and monitoring the detected hydraulic pressure value at the time with the stored detected hydraulic pressure value, an abnormality in the hydraulic equipment or mechanism can be detected at an early stage.

  The control device 14 has a table of control parameter sets shown in FIG. 2, and INDEX L, N, and H representing the weight of the movable type have two threshold values such that L <N <H. The control parameter value of each INDEX is set to a value that can stably move the movable type of the weight within the range in the shortest time. Note that this threshold value naturally increases as the number of control parameter sets increases. The control device 14 compares the value of the movable weight detected as described above with a threshold value to determine which INDEX the movable weight corresponds to. Then, by multiplying the percentage of the INDEX control parameters selected in the table by the value of each control parameter for which INDEX is set to N when the control device 14 is started and / or when the movable weight measurement is switched in the control mode. The control parameter value selected and switched is stored in the control device 14. Note that the control parameter set values may be selected / switched so that the parameter values are not absolute values but absolute parameter values and are replaced with the values as they are.

  As described above, the present invention detects the weight of the movable molds 5 and 6 together with the weight of the movable body in a state where the movable molds 5 and 6 are attached to the movable body, and according to the detected weight of the movable molds 5 and 6. Since the control parameters of the control device 14 for controlling the movement of the moving body are switched, when the movable molds 5 and 6 having a weight smaller than that of the standard mold are attached, the rotation time is longer than necessary and molding is performed. If the cycle time is extended or the movable molds 5 and 6 that are heavier than the standard mold are installed, the moment of inertia is large, and the positioning time will be increased. Accordingly, the movable molds 5 and 6 can be stably controlled in a short time without extending the molding cycle time.

  The present invention is not limited to the embodiments described above, and various modifications can be added and implemented without departing from the spirit of the invention. For example, in the above embodiment, the case of the vertical mold clamping device has been described. However, in the horizontal mold clamping device, the movable mold weight is detected by the hydraulic pressure of the hydraulic cylinder device provided in the moving guide portion of the movable platen. Alternatively, the present invention can be implemented by using a load cell provided in the movement guide portion of the movable platen. In addition, the mold opening / closing device has been described as being separated into 12 and 13, but both may be connected by one conduit, and the hydraulic pressure may be detected by one pressure detector, or the mold opening / closing device is configured by one. May be.

It is a block diagram which shows the outline | summary of the molding machine which implements the movable movement control method of this invention. It is a table | surface which shows the example of conversion of a control parameter.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Molding machine 2 Fixed platen 3,4 Fixed type 5,6 Movable type 7 Rotating plate 8 Movable platen 9 Rotation drive device 10,11 Mold clamping drive device 12,13 Mold opening / closing device 14 Control device 15 Mold opening chamber 16,18 Piston 17 type closed chamber 19 pressure chamber 20 position detector 21, 22 pressure detector

Claims (3)

In a movable mold movement control method of a molding machine that molds a molded product by matching a movable mold attached to a rotating disk rotated with respect to the movable disk to a fixed mold,
Wherein detecting the weight of the movable die in a state in which the movable die mounted on the rotary disc with the weight of the rotating disk of the weight or the movable platen and turntable, the turntable according to the size of the movable mold weight detected A movable movement control method for a molding machine, characterized in that the control parameter of a control device for controlling rotation drive by the rotation drive device is switched. The movable mold movement control method for a molding machine according to claim 1, wherein the weight detection of the movable mold is performed based on a load force of a mold opening / closing device that supports the movable disk and the rotating disk when the mold is opened. 3. The movable movement control method for a molding machine according to claim 1, wherein the control parameters are a moving speed, an acceleration time (position), and a deceleration time (position).

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