JP4884812B2 - Injection device and injection method - Google Patents

Description

  The present invention relates to an injection apparatus used in a molding machine such as a die casting machine.

  A so-called three-stage change injection device is known as an injection device that advances a plunger in a sleeve and injects molten metal into a cavity (for example, Patent Document 1). In the three-stage change injection device, at the start of injection, the forward speed of the plunger is controlled to be low in order to prevent the molten metal in the sleeve from entraining air. Next, in the vicinity of the molten metal reaching the gate, the forward speed of the plunger is switched to high speed, and the molten metal is filled into the cavity at high speed. When the filling is completed, the plunger driving mechanism is switched from the injection mechanism to the pressure raising mechanism, and the pressure inside the cavity is increased by the pressure raising mechanism through the plunger.

In such an injection apparatus, in order to obtain a molded product of a certain quality, in the filling operation for filling the cavity with the molten metal, the high-speed switching position for switching the forward speed of the plunger from the low speed to the high speed, and the forward movement of the plunger after the switching. In addition to managing the speed (high speed), in the pressure increasing operation for increasing the pressure of the molten metal in the cavity, the casting pressure and the pressure increasing time until the pressure increasing force reaches the casting pressure are managed. In other words, the filling time required for filling and the boosting time required for boosting are managed separately.
JP-A-10-52747

  When shifting from the completion of filling to the start of boosting, a time lag such as a boosting delay time due to secondary filling of the mold or a boosting time lag caused by the die casting machine occurs. In the conventional injection device, since the filling time and the pressure increase time are managed independently, for example, when a time lag more than expected occurs, no abnormality is detected. However, in practice, the time from the start of filling to the completion of pressurization is longer than the expected time, and a good product may not be hit.

  Patent Document 1 discloses that a time lag occurs from the completion of filling to the start of pressure increase. However, Patent Document 1 discloses improving the control method of the control valve to reduce the time lag, but does not disclose managing the time lag.

  An object of the present invention is to provide an injection apparatus capable of managing a time lag from the completion of filling to the start of pressure increase.

  An injection apparatus according to a first aspect of the present invention includes a sleeve communicating with a cavity, an injection plunger slidable within the sleeve, a driving means for driving the injection plunger, and directing the injection plunger toward the cavity. Control means for controlling the driving means so as to advance and fill the cavity with the molding material in the sleeve, and pressurize the molding material in the cavity by the injection plunger after completion of filling, The control means starts the advancement of the injection plunger and before the filling of the molding material into the cavity starts, and the pressure of the molding material is set to a predetermined set pressure by the pressure increase after the filling is completed. The filling boosting completion time is measured with the arrival time as the end point, and the filling boosting is completed thereafter based on the measurement result. During controls the operation of said drive means to a predetermined target value.

  Preferably, the start time point is a time point when a gate resistance occurs when the molding material is press-fitted into a gate communicating with the cavity.

  Preferably, the start time point is a time point at which the speed of the injection plunger is switched from a low speed to a high speed.

  Preferably, a pressure sensor for measuring the pressure in the cavity is provided, and the end time point is a time point when the pressure measured by the pressure sensor reaches the set pressure.

  Preferably, the control means includes a filling time from the start time until the filling of the molding material into the cavity is completed, and a boosting of the molding material in the cavity. Of the boosting time from the start to the end point, the operation of the driving means in the filling operation is performed such that the filling boosting completion time becomes the target value by correcting the filling time within a predetermined range. If the filling boosting completion time cannot be set to the target value only by correcting the filling time within the predetermined range, the filling boosting completion time becomes the target value by correcting the boosting time. The operation of the driving means in the boosting operation is controlled.

  An injection device according to a second aspect of the present invention includes a sleeve that communicates with a cavity, an injection plunger that is slidable within the sleeve, a drive unit that drives the injection plunger, and the injection plunger that faces the cavity. Control means for controlling the driving means and an input operation are received so as to advance and fill the cavity with the molding material in the sleeve, and pressurize the molding material in the cavity by the injection plunger after filling is completed. Input means and display means for displaying predetermined information, and the control means starts a time point after the start of advance of the injection plunger and before the completion of filling of the molding material into the cavity. In addition, the filling pressure increase that ends when the pressure of the molding material reaches a predetermined set pressure by the pressure increase after the filling is completed. The completion time is measured, the filling boosting completion time measured is displayed on the display unit, to correct the control parameter of Sekiru said drive means to said filling boosting completion time in accordance with the input operation received in said input means.

  According to the present invention, the time lag from the completion of filling to the start of pressure increase can be managed.

  FIG. 1 is a diagram showing a configuration of an injection apparatus 1 according to an embodiment of the present invention. In addition to the injection apparatus 1, a die casting machine is configured to include a mold clamping apparatus (not shown) that holds the mold 60. In the die casting machine, the mold 60 is closed and clamped by the mold clamping apparatus, and the injection apparatus. The molding cycle in which the injection and filling of the molten metal into the cavity 61 of the mold 60 according to 1, the mold opening of the mold 60 by the mold clamping device and the removal of the molded product from the mold 60 are sequentially performed is repeated. In addition, a molten metal is aluminum, for example, and is an example of the molding material of this invention.

  In FIG. 1, an injection sleeve 62 is connected to the mold 60 so as to communicate with a cavity 61. When the injection plunger 63 having the plunger tip 63 a fitted and inserted into the injection sleeve 62 moves forward, the molten metal supplied to the injection sleeve 62 is injected and filled into the cavity 61.

  The injection device 1 includes an injection cylinder 2, a hydraulic circuit 20, and a control device 40 in order to drive the injection plunger 63. The injection cylinder 2 and the hydraulic circuit 20 are an example of the driving means of the present invention.

  The injection cylinder 2 has a cylinder chamber 3 containing an injection piston 5 and a cylinder chamber 4 containing a boosting piston 6. The cylinder chambers 3 and 4 communicate with each other, and the cylinder chamber 4 has a larger diameter than the cylinder chamber 3. The cylinder chamber 3 is partitioned into a rod side chamber 3r and a head side chamber 3h by the injection piston 5, and the head side chamber 3h communicates with the cylinder chamber 4. The boosting piston 6 has a small-diameter portion 6 a and a large-diameter portion 6 b. The small-diameter portion 6 a is fitted in the head side chamber 3 h and the large-diameter portion 6 b is fitted in the cylinder chamber 4. The cylinder chamber 3 and the injection piston 5 constitute an injection mechanism that generates a driving force for injecting and filling molten metal, and the cylinder chamber 4 and the pressure increasing piston 6 constitute a pressure increasing mechanism that generates a driving force for increasing the pressure of the molten metal. The

  The injection piston 5 is connected to the injection plunger 63 by a piston rod 5a. The boosting piston 6 is disposed behind the injection piston 5 and has a larger diameter than the injection piston 5.

  The rod side chamber 3r and the head side chamber 3h are provided with a rod side pressure detector 48R and a head side pressure detector 48H, respectively, for detecting the pressure of the hydraulic oil. A position detector 49 for detecting the position of the piston rod 5a (injection plunger 63) is provided at the tip of the injection cylinder 2. The mold 60 is provided with a metal pressure detector 50 that detects the pressure of the cavity 61.

  The hydraulic circuit 20 includes first, second, third, fourth, fifth and sixth flow paths 25, 26, 27, 32, 33, 34, a check valve 22, a servo valve 28, and an on-off valve. 23, a hydraulic pressure source 30, and an accumulator 31.

  The first flow path 25 is connected to the head side chamber 3 h of the cylinder chamber 3, and supplies hydraulic oil for driving the injection piston 5. The second flow path 26 is connected to the pressure boosting piston 6 in the cylinder chamber 4 on the side opposite to the injection piston 5, and supplies hydraulic oil for driving the pressure boosting piston 6. One end of the third flow path 27 is commonly connected to the first flow path 25 and the second flow path 26, and the other end is connected to the hydraulic power source 30 and the accumulator 31. The fourth flow path 32 is connected to the rod side chamber 3r of the cylinder chamber 3 and discharges hydraulic oil from the rod side chamber 3r when the injection piston 5 moves forward. The fifth flow path 33 is connected to the cylinder chamber 3 side of the cylinder chamber 4 and discharges hydraulic oil from the cylinder chamber 4 when the boosting piston 6 moves forward. The sixth flow path 34 is formed by joining the fourth flow path 32 and the fifth flow path 33, and is connected to a discharge tank.

  The hydraulic source 30 supplies hydraulic oil to the third flow path 27. The accumulator 31 pressurizes the hydraulic oil supplied to the third flow path 27 to a predetermined pressure.

  The servo valve 28 is provided in the middle of the sixth flow path 34. The servo valve 28 includes an actuator 28a that opens and closes the valve and a position detector 28b that detects the opening of the valve. When the control signal 46s from the control device 40 is input to the actuator 28a, the opening degree of the valve is adjusted. The flow rate of the hydraulic oil discharged from the fourth and fifth flow paths 32 and 33 is controlled by controlling the opening of the valve. Further, the opening degree of the valve is detected by the position detector 28 b and fed back to the control device 40.

  The check valve 22 is provided in the middle of the first flow path 25. The check valve 22 allows the flow of hydraulic oil supplied toward the injection cylinder 2 through the first flow path 25 and prevents the flow of hydraulic oil from the injection cylinder 2 side toward the first flow path 25. .

  The on-off valve 23 is a pilot check valve provided in the middle of the second flow path 26. This open / close valve 23 opens and closes the second flow path 26 by a pilot operation, and allows only the hydraulic oil to flow into the cylinder chamber 4 when opened.

  The control device 40 includes a processor (CPU) 41, a memory (ROM / RAM) 42, an input circuit 43, an output circuit 44, an amplifier 46, a display 45, a data input device 47, and the like. The memory 42, the input circuit 43, and the output circuit 44 are connected to the processor 41 by a bus. The memory 42 stores a program for driving and controlling the servo valve 28 and the like.

  A data input device 47, a position detector 49, a head side pressure detector 48H, a rod side pressure detector 48R, and the like are connected to the input circuit 43. The input circuit 43 includes data input from the data input device 47, Pressure information 48hs detected by the head side pressure detector 48H, pressure information 48rs detected by the rod side pressure detector 48R, position information 49s of the injection plunger 63 detected by the position detector 49, and metal detected by the metal pressure detector 50 Pressure information 50 s and the like are output to the processor 41.

  The processor 41 performs operations such as calculating a command for the servo valve 28 based on a program stored in the memory 42. For example, the processor 41 performs injection speed control based on the position information 49s detected by the position detector 49, and based on the pressure information 48hs of the head side pressure detector 48H and the pressure information 48rs of the rod side pressure detector 48R. Perform injection pressure control. The processor 41 measures various times based on the count of the internal clock.

  An amplifier 46 and a display 45 are connected to the output circuit 44, and the output circuit 44 outputs data from the processor 41 and the like to the amplifier 46 and the display 45. The amplifier 46 amplifies the control command calculated by the processor 41 and outputs it to the actuator 28 a of the servo valve 28. The display unit 45 includes a liquid crystal display, a segment display unit, and the like, and displays predetermined information.

  Next, an example of the operation of the injection apparatus 1 having the above configuration will be described with reference to the injection waveform of FIG. 2 shows the change over time of the displacement of the injection plunger 63, the dotted line LN1 in the lower part of FIG. 2 shows the change over time of the speed of the injection plunger 63, and the solid line LN2 in the lower part of FIG. 2 shows the change over time of the injection pressure. The axis is time. The injection pressure is a differential pressure between the pressure in the rod side chamber 3r and the pressure in the head side chamber 3h, or a pressure acting on the molten metal via the plunger tip 63a of the injection plunger 63.

First, after supplying a predetermined amount of molten metal into the sleeve 62, the servo valve 28 is controlled by the control device 40, and the injection piston 48 is driven so that the plunger speed V becomes the low speed plunger speed _VL . That is, a filling operation for injecting and filling molten metal into the cavity 61 is started.

  The control device 40 sequentially monitors the position information of the injection plunger 63 detected by the position detector 49 from the time point O at which the injection plunger 63 starts moving forward, and at the time point D when the injection plunger 63 reaches the high-speed switching position Pos1, the servo. The opening degree of the valve 28 is increased. The high-speed switching position Pos1 is set, for example, at a position where the tip of the molten metal injected from the sleeve 62 toward the cavity 61 substantially reaches the gate Gt of the cavity 61.

  As the opening degree of the servo valve 28 increases, the flow rate of the hydraulic oil flowing out from the rod side chamber 3r of the cylinder chamber 3 increases and the flow rate of the hydraulic oil flowing into the head side chamber 3h of the cylinder chamber 3 increases. The forward speed of 5, ie the plunger speed V increases. Further, the injection pressure P increases as the injection plunger 63 accelerates.

The plunger speed V and the injection pressure P affect each other, and follow the high-speed plunger speed V _H or the filling pressure P _H while oscillating. For example, the plunger speed V once increases to a magnitude exceeding the high-speed plunger speed V _H (time point D to time point F). Injection pressure P starts to rise from the time D, once levels off at the time E fast acceleration time through the T _A. At point F, the molten metal is caused gate resistance when being pressed into the gate Gt, the injection pressure P rises again, it converges to the filling pressure P _H at time G. On the other hand, the plunger velocity V is once decelerated at the time point F where the gate resistance is generated, the injection pressure P starts increasing again from time G that converges to the filling pressure P _H, converges fast plunger speed V _H at time H.

After switching the plunger speed V faster plunger speed V _H, the molten metal is to some extent filled cavity 61 (point I), the plunger speed V is rapidly decelerated. On the other hand, the injection pressure P increases rapidly. A surge pressure is generated at time point J. That is, the filling operation is completed.

  Thereafter, the control device 40 sets the servo valve 28 to a predetermined opening and makes the opening / closing valve 23 openable. As a result, the opening / closing valve 23 provided in the second flow path 26 opens according to the opening degree of the servo valve 28, and hydraulic oil is discharged from the fifth flow path 33 and from the third flow path 26. Hydraulic oil is supplied to the cylinder chamber 4 through the opening / closing valve 23.

  When hydraulic oil is supplied to the cylinder chamber 4, the boosting piston 6 moves forward. When the boosting piston 6 moves forward, the pressure of the hydraulic oil between the boosting piston 6 and the injection piston 5 increases, so that the check valve 22 is closed by itself. In other words, the hydraulic oil traveling toward the cylinder chamber 3 through the first flow path 25 is blocked, and the space between the boosting piston 6 and the injection piston 5 in the cylinder chamber 3 is sealed.

  Then, the injection piston 5 is pushed in the forward direction from behind, and the injection pressure P that has once decreased after the occurrence of the surge pressure rises again from the time point L, and reaches the casting pressure (final pressure) Pmax at the time point N.

  FIG. 3 is a diagram for explaining the outline of the present invention in comparison with the prior art.

Conventionally, the four items of the high-speed switching position Pos1, the high-speed plunger speed V _{H of} the plunger, the casting pressure Pmax, and the pressurizing time from the time point L at which the pressurization is started to the time point N at which the injection pressure becomes the casting pressure Pmax have been managed. . However, as shown in FIG. 2, a time lag _TL occurs from the time point J at which the surge pressure is generated to the time point L at which the injection pressure actually starts to rise. Therefore, for example, when an unexpected time lag occurs, the time from the start of filling to the completion of pressure increase becomes longer than the assumed time, and a non-defective product may not be hit.

Therefore, in this embodiment, the fill time T _F of filling the molten metal into the cavity, the time lag T _L, the filling boost completion time T _C is the sum of the boosting time T _P is measured, the filling boost completion time T _C to manage.

Starting point of the filling boost completion time T _C (the starting point of the fill time T _F), as shown in FIG. 2, for example, when the gate resistance occurs (time F). The time point F is, for example, an increase start point of the differential pressure between the detection pressure of the rod side pressure detector 48R and the detection pressure of the head side pressure detector 48H, a decrease start point of the plunger speed detected by the position detector 49, or the like. It is specified by detecting at least one of them.

Alternatively, the starting point of the filling boost completion time T _C is the time D to switch to a high speed the speed of the injection plunger 63 from the low speed. The high-speed switching position Pos1 may be any of a position before the molten metal passes through the gate Gt, a position where the molten metal passes through the gate Gt, and a position after the molten metal passes through the gate Gt, but the molten metal passes through the gate Gt. The position to do is preferable.

End point of the filling boost completion time T _C (end point of the boosting time T _P) is, for example, a point M of the detected pressure of the metal pressure detector 50 reaches a predetermined set pressure Pt. The set pressure Pt may be appropriately set within a range equal to or lower than the casting pressure Pmax. In FIG. 2, the detection pressure of the metal pressure detector 50 is assumed to be equal to the injection pressure.

The end point of the filling time _TF (the start point of the time lag _TL ) is, for example, the time point J when the surge pressure is generated. The time point J is detected, for example, by detecting the generation of surge pressure from the difference between the detected pressure of the rod side pressure detector 48R and the detected pressure of the head side pressure detector 48H.

Starting point of the boosting time T _P (end point of the time lag T _L) is, for example, when L the injection pressure starts to rise. The time point L is, for example, the starting point of the increase in the differential pressure between the detected pressure of the rod side pressure detector 48R and the detected pressure of the head side pressure detector 48H after the occurrence of the surge pressure, or the rising start of the detected pressure of the metal pressure detector 50. It is specified by detecting at least one of points.

FIG. 4 is a flowchart showing the procedure of the injection control process executed by the control device 40. This process is executed after completion of mold clamping by the mold clamping device in each molding cycle. In Figure 4, description will be given of a case where the time that the gate resistor the starting point of the filling boost completion time T _C has occurred.

  In step S1, low speed injection is started (time point O). In step S2, it is determined whether or not the injection plunger 63 has reached the high speed switching position Pos1, and the low speed injection is continued until it is determined that the injection plunger 63 has reached. If it is determined that the high speed switching position Pos1 has been reached, the plunger speed is switched to high speed and high speed injection is started (step S3, time point D).

In step S4, it is determined whether or not gate resistance has occurred, and the process waits until it is determined that gate resistance has occurred. If the gate resistance is determined to have occurred, it starts measuring the filling boost completion time T _C and the filling time T _F (step S5, when F).

  In step S6, the control device 40 determines whether or not the boosting start condition is satisfied, and continues high-speed injection until it is determined that the boosting start condition is satisfied. The pressurization start condition is, for example, that a surge pressure has been detected and that the injection plunger 63 has reached a predetermined position.

When determining that the boosting start condition is satisfied, the control device 40 ends the measurement of the filling time _TF , starts the measurement of the time lag _TL (step S7, time point J), and commands the start of boosting (step). S8). In the step of starting the pressure increase, as described above, the servo valve 28 is set to a predetermined opening, and the control signal 46s for opening the opening / closing valve 23 is output. Thereby, the boosting operation is started.

In step S9, the control device 40 determines whether or not the pressurization of the molten metal has been started. For example, it is determined whether or not the differential pressure between the detected pressure of the rod side pressure detector 48R and the detected pressure of the head side pressure detector 48H has started to rise. Controller 40, when determining that the boosting is started, it starts measuring the boosting time T _P with ends the measurement of the time lag T _L (step S10, time L).

In step S11, the control device 40 determines whether or not the metal pressure detected by the metal pressure detector 50 has reached a predetermined set pressure Pt, and waits until it is determined that the metal pressure has been reached. Controller 40, when determining that the metal pressure reaches the set pressure Pt ends the measurement of the filling boost completion time T _C and boosting time T _P (step S12, time M). Further, the boosting operation is terminated, and a control signal is output to the servo valve 28 or the like so as to perform the pressure holding operation (step S13).

Incidentally, the starting point of the filling boost completion time T _C when the injection plunger 63 and the time D has reached the high-speed switching position Pos1 may be omitted the step S4. In FIG. 4, when the boosting start condition is satisfied, the filling time measurement is finished and a boosting start command is output (steps S <b> 6 to S <b> 8), and the condition that defines the filling time end point is boosted. Although it is the same as the start condition, the arrival of the injection plunger 63 at a predetermined position is set as the pressure increase start condition, and the detection of the surge pressure is set as a condition for defining the end point of the filling time. Good. However, since there is a variation (time lag) for each cycle from when one condition is satisfied to when the other condition is satisfied, the boosting start condition and the condition for defining the end point of the filling time _TF are: better to the same may be eliminated the influence of such variations from the time lag T _L, it is easy to manage the time lag T _L.

At the end of measurement of the filling time T _F , time lag T _L , boosting time T _P , filling boosting completion time T _C , or until the next molding cycle is started from step S 13, etc. Then, a control signal is output so that the measured time is displayed on the display unit 45. The operator based on the time displayed by a predetermined input operation to the data input device 47, as fill boost completion time in the next molding cycle T _C reaches a predetermined target value, fast plunger speed The setting of V _H (filling time T _F ), boost time _TP, etc. is changed. The control device 40 corrects the control parameters of the hydraulic circuit 20 and the like based on the high-speed plunger speed V _{H and the} like after the setting change. For example, the opening degree of the servo valve 28 at the time of high-speed injection or pressure increase is corrected. Then, the control device 40 controls the operation of the hydraulic circuit 20 and the like based on the corrected control parameters in the subsequent molding cycles.

Further, based on the filling boost completion time T _C measured as fill boost completion time T _C in the next molding cycle reaches a predetermined target value, the control unit 40 performs correction control such as a hydraulic circuit 20 Also good. In the correction, the filling time _TF and the boosting time _TP are corrected, and the time lag _TL is set to a constant value that cannot be corrected. Moreover, priority is given to the correction of the fill time T _F for correction of the boosting time T _P. Specifically, it is as follows.

FIG. 5 is a flowchart showing the procedure of the filling time correction process executed by the control device 40. This process, after the end measure of the filling boost completion time T _C (after step S12), the executed until previous (previous step S3) the high speed injection is started at the next molding cycle.

In step S21, the control unit 40 compares the fill booster completion time and T _C measured by the step S5 and step S12, and the set target value. In step S22, a correction amount related to the filling time _TF is determined based on the comparison result. For example, only the difference between the measured filled boosted completion time T _C and the target value, so as to shorten or lengthen the filling time T _F, determines a correction amount of the fast plunger speeds V _H.

In the period from step S3 to step S8, the control device 40 controls the servo valve based on the plunger speed specified from the detection value of the position detector 49 so that the corrected high-speed plunger speed _VH is obtained. The 28 opening is feedback controlled. In step S22, the correction amount of the opening degree of the servo valve 28 may be directly determined.

The filling time _TF is defined as a range that can be corrected depending on the performance limit of the injection cylinder 2 and the hydraulic circuit 20 and the necessity of obtaining a constant hot water flow in order to obtain a certain quality. Accordingly, the determined correction amount of fill time T _F in a predetermined set range at step S22, only the correction amount of fill time T _F may not be a T _C to a target value filled boost completion time. In this case, the boost time _TP is also corrected.

FIG. 6 is a flowchart illustrating the procedure of the boost time correction process executed by the control device 40. This process, after the end measure of the filling boost completion time T _C (after step S12), the executed until (before step S8) to step-up start instruction is made in the next molding cycle.

At step S25, the control unit 40, a difference between the measured filled boosted completion time T _C and the target value, and a correction amount of fill time T _F which is calculated in step S22, it corrects the fill time T _F It calculates a correction amount of the still necessary fill boost completion time T _C. In step S26, the control unit 40, as boosting time T _P in accordance with the required correction amount is shortened or extended, it determines the amount of correction according to the boosting time T _P. For example, the opening degree of the servo valve 28 in the pressure increasing operation is corrected. However, the boosting time _TP may also be determined in a predetermined setting range set based on the performance limit of the hydraulic circuit 20 and the like, similarly to the filling time _TF .

  And between step S8 to step S13, the control apparatus 40 controls the servo valve 28 so that it may become the corrected opening degree.

Correction of boosting time T _P is not determined based on the correction amount of the determined fill time T _F at step S22, is determined based on the correction amount of fill time T _F which is actually done in the current cycle You can also.

In this case, the process of FIG. 5 is executed after the completion of the measurement of the filling time _TF (after step S7) and before the pressure increase start command is given in the current molding cycle (before step S8).

Then, in step S25, the control unit 40, the difference and, filling time T _F and filling time measured in the current cycle measured in the previous cycle the filling boost completion time T _C and the target value measured in the previous cycle since the difference between T _F (correction amount of the filling is actually done time T _F), still calculates a correction amount of the required fill boost completion time T _C. In step S26, the control unit 40, as boosting time T _P in accordance with the required correction amount is shortened or extended, it determines the amount of correction according to the boosting time T _P.

By doing so, if the correction of the fill time T _F has not been performed as set can also be corrected appropriately filled boost completion time T _C. Of the filling time T _F and boosting time T _P, so as not to be at least one correction, it may be set by the operator.

In, from the time before the completion of filling of molten metal F (or point D), and measuring the filling boost completion time T _C to the point M where the pressure of the molten metal reaches the set pressure Pt, the measurement result above embodiments based on, filling the boost completion time T _C in the later to control the operation of the hydraulic circuit 20 so that the target value. That is, is the management items fill boost completion time T _C, includes a time lag T _L that occurs to the boosted starting from the filling completion. Therefore, it is possible to manage the time lag _TL that has not been managed in the past, and to ensure a stable and constant quality.

Further, a plurality of control items were managed individually conventional such fast plunger speed V _H and boosting time T _P, since it is treated as a correction item for correcting the fill booster completion time T _C, the management items It will be centralized. Therefore, the stability of quality is improved synergistically. That is, conventionally, even if the values of a plurality of management items such as the high-speed plunger speed V _H are managed so as to fall within a predetermined management range, depending on the values of other management items, the filling pressurization completion time becomes long and hits a good product. In some cases, the management is not necessarily performed properly. However, in the present embodiment, since the management is performed on the time axis, the management can be performed correctly.

In addition, when the high-speed switching position is controlled and the high-speed switching position is changed as in the past, the high speed before the gate where the molten metal switches at high speed before passing through the gate, and the high speed at which the molten metal switches at high speed when passing through the gate. , 3 patterns of high speed after the gate are generated in which the molten metal switches at high speed after passing through the gate. For example, at high speed before gate, there is no gate resistance at high speed switching, so the plunger speed V is larger than the set waveform. Therefore, quantitative management of high-speed plunger speed V _H has been difficult. However, such a problem does not occur in this embodiment.

The starting point of the filling boost completion time T _C, since it is a time point D point F or fast switching gate resistance occurs, the filling boost completion time T _C be defined in a proper range, proper management can be performed. That is, slow plunger speed V _L is preferably to be maintained at critical velocity in order to prevent the entrainment of air, even including the time doing a low-speed injection to fill the boost completion time T _C, a slow plunger speed V it is difficult to be corrected item for correcting the fill booster completion time T _{C L,} and the other hand, until filled before the melt hardens, the viewpoint of boosting, the boost is completed after starts filling since it is desirably to properly manage time, time D of point F or fast switching gate resistance occurs it is properly define the starting point of the filling boost completion time T _C.

Since it is the time when the metal pressure metal pressure detector 50 reaches the set pressure Pt for measuring the pressure in the cavity and the end point of the filling boost completion time T _C, as in the prior art, the boost completion by the pressure of the injection cylinder As compared with the case of determining the above, it is possible to accurately determine the completion of boosting. For example, when the determination is made based on the pressure of the injection cylinder as in the prior art, the pressure of the injection cylinder rises even when the molten metal has solidified before the completion of pressurization. That is, the detection of the pressure of the injection cylinder cannot accurately detect the pressure of the molten metal. However, by detecting the pressure of the molten metal directly, it is possible to determine accurately boosting completed, hence, it is possible to manage accurately fill boost completion time T _C.

Of the filling boost completion time T _C, by giving priority to the correction of the fill time T _F for correction of the boosting time T _P, the process of filling the molten metal into the cavity 61 is stably performed. For example, when a need for correction of the filling boost completion time T _C occurs, one of the filling time T _F and boosting time T _P, or, it is possible that both are outside the proper range. In this case, by keeping the proper range of the filling time T _F correcting performed preferentially filling time T _F, can be filled with molten metal stably to the cavity 61.

  The present invention is not limited to the above embodiment, and may be implemented in various aspects.

  The injection apparatus to which the present invention is applied is not limited to an injection apparatus for a die casting machine as long as it can inject a molding material into a cavity. Further, the injection device is not limited to the three-stage change type as long as the filling operation and the boosting operation of boosting after completion of filling are performed. For example, a multistage change type may be used.

  The start time of the filling pressurization completion time may be specified in a range after the start of advancement of the injection plunger and before the completion of filling of the molding material into the cavity. It is not limited. This is because the time lag that occurs after the completion of filling is included in the filling pressurization completion time, and the time lag can be managed if it is defined in the above range. For example, the time point E or the time point G in the embodiment may be set as the start time point.

  If the filling pressurization completion time ends when the pressure of the molding material reaches a predetermined set pressure due to the pressurization after filling, the time lag before the molten metal pressure starts to rise is included in the filling pressurization completion time. And manage the time lag. Therefore, the end point of the filling pressurization completion time does not have to be at or near the time when the pressure of the molten metal reaches the final pressure.

  Also, the end time of the filling time and the start time of the pressure increase time can be defined as appropriate. This is because, regardless of how these are defined, the time lag can be managed if the start time and end time of the filling boosting completion time are defined so as to include the time lag.

The figure which shows the whole structure of the injection device which concerns on one Embodiment of this invention. The figure which shows the injection waveform of the injection apparatus of FIG. The figure explaining the outline | summary of this invention by the comparison with a prior art. The flowchart which shows the procedure of the injection control process which the control apparatus of the injection device of FIG. 1 performs. The flowchart which shows the procedure of the filling time correction process which the control apparatus of the injection device of FIG. 1 performs. The flowchart which shows the procedure of the pressure | voltage rise time correction process which the control apparatus of the injection device of FIG. 1 performs.

Explanation of symbols

61 ... cavity, 62 ... sleeve, 63 ... plunger, 2 ... injection cylinder (drive means), 20 ... hydraulic circuit (drive means), 40 ... controller (control means), T C _... filling boost completion time, F ... time (Starting time of filling pressurization completion time), M... Time (ending time of filling pressurization completion time).

Claims (4)

A sleeve communicating with the cavity;
An injection plunger slidable in the sleeve;
Drive means for driving the injection plunger;
The drive means is controlled to advance the injection plunger toward the cavity to fill the cavity with the molding material in the sleeve and to pressurize the molding material in the cavity by the injection plunger after the filling is completed. Control means to
With
The control means sets the pressure of the molding material to a predetermined set pressure as a start time after the injection plunger starts to advance and before the cavity is completely filled with the molding material. Measuring the filling boosting completion time with the end point as the end point, and controlling the operation of the driving means based on the measurement result so that the filling boosting completion time becomes a predetermined target value thereafter ,
The start time is a time when a gate resistance occurs when the molding material is pressed into a gate communicating with the cavity, or a time when the speed of the injection plunger is switched from a low speed to a high speed.
Y de devices. A sleeve communicating with the cavity;
An injection plunger slidable in the sleeve;
Drive means for driving the injection plunger;
The drive means is controlled to advance the injection plunger toward the cavity to fill the cavity with the molding material in the sleeve and to pressurize the molding material in the cavity by the injection plunger after the filling is completed. Control means to
With
The control means sets the pressure of the molding material to a predetermined set pressure as a start time after the injection plunger starts to advance and before the cavity is completely filled with the molding material. The filling boosting completion time with the end point as the end time is measured, and based on the measurement result, the filling of the molding material into the cavity from the start time included in the filling boosting completion time is thereafter performed. Of the filling time to completion and the pressure increasing time from the start of the pressurization of the molding material in the cavity to the end time, the filling time is completed within a predetermined range to complete the filling pressure increase. The operation of the driving means in the filling operation is controlled so that the time becomes the target value, and the filling boosting completion time is advanced only by correcting the filling time. The boosting time to control the operation of the drive means in the step-up operation as the filling boosting completion time becomes the target value by being corrected in the case can not be the target value
Y de devices. A sleeve communicating with the cavity;
An injection plunger slidable in the sleeve;
Drive means for driving the injection plunger;
The drive means is controlled to advance the injection plunger toward the cavity to fill the cavity with the molding material in the sleeve and to pressurize the molding material in the cavity by the injection plunger after the filling is completed. Control means to
An input means for accepting an input operation;
Display means for displaying predetermined information;
With
The control means includes
A time point after the start of advancement of the injection plunger and before completion of filling of the molding material into the cavity is set as a starting time point, and a time point when the pressure of the molding material reaches a predetermined set pressure due to pressure increase after completion of filling. Filling pressurization completion time as an end time, included in the filling pressurization completion time , filling time from the start time to completion of filling of the molding material into the cavity, and included in the filling pressurization completion time Measuring the time lag from the end of the filling time to the start of the pressurization time included in the pressurization time from the start of the pressurization of the molding material to the end point, and the filling pressurization completion time ,
The measured filling boosting completion time , the filling time, the boosting time and the time lag are displayed on the display,
Accepting a change in target value for the plunger speed or the filling time when performing high-speed injection, and the pressure increase time by an input operation on the input means ,
An injection device that controls the driving means so that a plunger speed or the filling time when performing high-speed injection, and the pressure increase time become a target value after the change . An injection plunger slidable in a sleeve communicating with the cavity is advanced by the driving means toward the cavity to fill the cavity with the molding material in the sleeve, and the molding material in the cavity is filled after the filling is completed. An injection method in which the pressure is increased by the injection plunger,
A time point after the start of advancement of the injection plunger and before completion of filling of the molding material into the cavity is set as a starting time point, and a time point when the pressure of the molding material reaches a predetermined set pressure due to pressure increase after completion of filling. The filling boosting completion time as an end time is measured, and based on the measurement result, the operation of the driving means is controlled so that the filling boosting completion time becomes a predetermined target value thereafter.
The start time is a time when a gate resistance occurs when the molding material is pressed into a gate communicating with the cavity, or a time when the speed of the injection plunger is switched from a low speed to a high speed.
Injection method.

Images