JP2008073708A - Hybrid high speed injection apparatus having excellent controllability, and controlling method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an injection apparatus having excellent controllability and maintainability in a small size and a light weight with which a plunger is driven with a simple driving mechanism. <P>SOLUTION: Regarding the hybrid high speed injection apparatus having excellent controllability, in an injection apparatus where molten metal is filled up into a cavity in a die by driving a plunger, the rear part of a hydraulic cylinder with a built-in plunger rod controlled by a hydraulic control mechanism is provided with a piston rod controlled by an advancing/retreating control mechanism. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

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

  In die casting of aluminum alloy or the like, a hydraulic die casting machine that conventionally drives an injection plunger with a hydraulic cylinder has been used. In this die casting machine, the pressure and flow rate of the hydraulic oil supplied to the hydraulic cylinder that drives the injection plunger are adjusted to control the injection plunger speed and pressure.

  In such die casting, in order to improve the quality of the cast product, it is important to stably maintain the injection plunger speed. When controlling the speed of the injection plunger driven by the hydraulic cylinder, the hydraulic cylinder Since the flow rate of the hydraulic oil supplied to the engine is controlled by a hydraulic control valve, the response is low and it is difficult to maintain a stable injection plunger speed.

  In addition, when controlling the speed of the injection plunger driven using a hydraulic cylinder, it is difficult to detect the load received by the injection plunger and it is difficult to perform feedback control. Difficult to maintain.

  Furthermore, when hydraulic pressure is used as the drive source for the injection plunger, the energy efficiency is low, and the working environment is deteriorated due to environmental pollution due to hydraulic oil leakage, processing of hydraulic oil waste liquid, and the like.

  In order to improve the above points, an injection device has been proposed in which a ball screw mechanism driven by an electric servo motor and a hydraulic cylinder operated by hydraulic pressure of a hydraulic pump and an accumulator are connected in series to an injection plunger (Patent Document 1). ~ 3).

  In the above injection device, an electric servo motor is used to increase the controllability of the injection speed during high-speed injection, and an injection cylinder using a hydraulic cylinder to obtain a sufficiently large pressure increase / holding force during pressure increase / hold pressure Drive. In this drive mechanism, the thrust of the hydraulic cylinder is transmitted to the injection plunger through the shaft of the ball screw, so that the shaft diameter of the ball screw needs to be increased to some extent from the viewpoint of securing mechanical strength. However, this increase in diameter prevents the injection plunger speed from being increased and stabilized.

  Further, while the injection plunger is moved forward by the electric servo motor, it is necessary to supply the hydraulic oil to the hydraulic cylinder following the advance, but the hydraulic circuit for the hydraulic supply follow-up supply becomes complicated, Control itself becomes difficult.

  Furthermore, when the injection pressure is increased and maintained with hydraulic pressure, feedback control based on the rotation speed of the electric servo motor is canceled, and torque in the direction in which the injection plunger is moved forward is always generated. It is necessary to perform control so as not to react with the cylinder, and the overall circuit configuration including the hydraulic circuit must be complicated.

  After all, in the injection device (see Patent Documents 1 to 3), the control circuit and the control method must be complicated. Moreover, this complication does not necessarily lead directly to an increase in speed and stabilization of the injection plunger speed.

  Therefore, in order to improve the above points, an injection device that drives the injection plunger by connecting in parallel the ball screw mechanism driven by the electric servo motor and the hydraulic cylinder operated by the hydraulic pressure of the hydraulic pump and accumulator to the injection plunger is proposed. (See Patent Document 4).

  In the above injection device, the thrust of the hydraulic cylinder is directly transmitted to the injection plunger without passing through the ball screw, so there is no need to increase the shaft diameter of the ball screw, and in this respect, controllability is improved. Yes.

  However, while the injection plunger is moved forward by the electric servomotor, it is necessary to supply the hydraulic oil to the hydraulic cylinder following the advancement, and when the injection pressure is increased and held by hydraulic pressure, the electric servo is used. It is necessary to cancel the feedback control based on the rotation speed of the motor, always generate torque in the direction to advance the injection plunger, and control so that the control torque of the electric servo motor does not become a reaction force against the hydraulic cylinder. This is the same as the case of the injection apparatus disclosed in Documents 1 to 3, and the control circuit and the control method must be complicated after all.

  Furthermore, since the injection apparatus described in Patent Document 4 includes a hydraulic tank and a hydraulic pump, the scale of the apparatus is increased, the maintainability is deteriorated, and the working environment is deteriorated.

  By the way, in recent years, in die casting, it is required to manufacture a cast product having a complicated shape at high speed and high quality with a high yield. As one method for responding to this, it is considered to use a large and large output motor for driving the injection plunger.

  However, large motors generally have poor responsiveness, and the timing for switching the injection plunger from low speed to high speed is delayed, making it difficult to maintain the quality of the cast product.

  In addition, when a large motor is used in, for example, a 350 ton class die casting machine, a large motor of 500 Kw is required for instantaneous output. Furthermore, a high-pitch screw feed mechanism (for example, 2000 rpm) is required to increase the speed of the injection plunger. In order to obtain a high speed of 5 m / s, a screw with a pitch of 150 mm is required, and a screw with a pitch of 90 mm is required even at 3 m / s).

  After all, the drive device that drives the injection plunger using a large and large output motor must be large-scale and large-capacity, its controllability is reduced, and a large-scale and large-capacity drive device is used. Then, the inertial mass of the cast product becomes large, and burrs are easily generated in the cast product, so that it becomes difficult to maintain the quality of the cast product.

  There is a demand for high-speed, high-quality, high-yield production of castings with complex shapes by die casting, and with a simple drive mechanism, controllability, excellent maintainability, and small size・ Lightweight, energy-saving high-speed injection device is required.

  In view of the above request, the applicant of the present invention has a controllability characterized in that, in Patent Document 5, the hydraulic control mechanism connected with the plunger is provided with an advance / retreat control mechanism that drives the hydraulic control mechanism in the advance / retreat direction of the plunger. An excellent hybrid injection device was proposed.

  According to the hybrid injection device proposed in Patent Document 5, the injection device itself can be made smaller and lighter than the conventional device, and switching and pressure increase at the low speed-high speed switching position can be performed with high responsiveness and high accuracy. Since it can be controlled, a high-quality casting can be manufactured with a high yield, but there is a limit to miniaturization and weight reduction.

JP 2000-033472 A JP 2000-084654 A JP 2001-100126 A JP 2006-000887 A Japanese Patent Application No. 2006-115859

  In the conventional injection device that controls the injection plunger with an electric mechanism and a hydraulic mechanism, one of the factors that hinders further miniaturization and weight reduction and further speeding up is to drive the injection plunger directly by the electric mechanism. It is to adopt an advancing and retreating structure. That is, when the injection plunger is advanced and retracted by the electric mechanism, it must be advanced and retracted including the hydraulic mechanism that drives the injection plunger, so there is a limit to the reduction in size and weight of the electric mechanism.

  An object of the present invention is to provide a high-speed injection device that is small, lightweight, excellent in controllability, and excellent in maintainability, in which the plunger is driven by a simple drive mechanism in view of the above-mentioned limitations.

  The inventor has intensively studied a compact and lightweight high-speed injection structure (hybrid high-speed injection mechanism) capable of manufacturing a cast product having a complicated shape with high quality and high yield by using both an electric mechanism and a hydraulic mechanism.

  As a result, the present inventor provides a piston rod that is advanced and retracted by an electric mechanism in a hydraulic cylinder behind the piston rod connected to the plunger, and if the two piston rods are driven individually or integrally as appropriate, the plunger It has been found that it is possible to accurately control the forward / backward movement at a high speed, and to manufacture a cast product having a complicated shape with high quality and high yield.

  This invention was made | formed based on the said knowledge, and the summary is as follows.

  (1) In an injection apparatus that drives a plunger and fills a mold cavity with a molten metal, a piston rod controlled by an advance / retreat control mechanism is provided behind a hydraulic cylinder that incorporates a plunger rod controlled by a hydraulic control mechanism. Hybrid high-speed injection device with excellent controllability.

  (2) The hybrid high-speed injection device with excellent controllability according to (1), wherein the advance / retreat control mechanism is a ball screw mechanism.

  (3) The hybrid high-speed injection device with excellent controllability according to (2), wherein the ball screw mechanism is driven by a servo motor.

(4) A piston rod controlled by the advance / retreat control mechanism is provided behind the hydraulic cylinder containing the plunger rod controlled by the hydraulic control mechanism, and the hydraulic control mechanism and the advance / retreat control mechanism are driven in cooperation to form a molten metal mold. In a control method for controlling the filling of the cavity,
(I) The advance / retreat control mechanism is driven, and the plunger rod is integrated with the piston rod and advanced until reaching the low speed-high speed switching position.
(Ii) A hybrid high-speed injection control method characterized by driving the hydraulic control mechanism and advancing the plunger at a high speed in cooperation with the advance / retreat control mechanism.

  (5) The hybrid high-speed injection control method according to (4), wherein the drive of the hydraulic control mechanism is real-time feedback controlled according to a rising curve up to a preset injection pressure.

  According to the present invention, the injection device itself can be further reduced in size and weight as compared with the conventional device, and switching and pressure increase at the low speed-high speed switching position can be controlled with high responsiveness and high accuracy. Therefore, according to the present invention, a high-quality cast product can be manufactured with a high yield. Moreover, the present invention is remarkably excellent in maintainability as the size and weight are further reduced.

  A hybrid high-speed injection device (device of the present invention) according to the present invention will be described with reference to the drawings. FIG. 1 shows one structure of the device of the present invention. FIG. 10 shows another structure of the device of the present invention.

  1) First, the structure shown in FIG. 1 and its driving mode will be described.

  In the structure shown in FIG. 1, a mold cavity 5 is formed as a casting space in a state where the movable mold 4 fixed to the movable platen 2 is closed with respect to the fixed mold 3 fixed to the fixed platen 1. An injection sleeve 6 is connected to the fixed mold 3, and a plunger rod 8 having a plunger tip 7 sliding at the tip of the injection sleeve 6 is driven at high speed, and the molten metal Me held in the injection sleeve 6 is made of gold. The mold cavity 5 is filled.

  The rear end of the plunger rod 8 constitutes a piston 13 that slides in the hydraulic cylinder 9, and the plunger rod 8 is driven by a hydraulic control mechanism 10 including the hydraulic cylinder 9.

  The hydraulic control mechanism 10 includes an accumulator 11 connected to a hydraulic cylinder 9 via a high-speed valve 12, and activates the electromagnetic switching mechanism M in accordance with a control signal (not shown) to open the high-speed valve 12, The accumulator 11 supplies the oil chamber 16H behind the piston 13 to drive the plunger rod 8.

  In order to control the driving of the plunger rod 8 with high accuracy, a hydraulic sensor (not shown) for detecting the hydraulic pressure of the hydraulic oil is attached to the inside of the accumulator 11 and the oil chambers 16R and 16H of the hydraulic cylinder 9. ing.

  Then, in the oil chamber 16H behind the piston 13, the plunger rod 8 is driven with high precision, and a high-quality cast product is manufactured with high yield. A piston rod 14 that realizes high-speed injection in cooperation with the rod 8 is provided. This is a feature of the present invention.

  The rear end of the piston rod 14 is connected to the end of the ball screw 17 of the ball screw mechanism 18 via the connecting member 15, and a control device (not shown) constituting an advance / retreat control mechanism together with the servo motor 19 and the ball screw mechanism 18. By controlling the rotation of the servo motor 19 in accordance with the signal from, the advance / retreat of the piston rod 14 can be controlled including the advance / retreat speed.

  That is, by rotating the servo motor 19 left and right at a required number of rotations according to the control signal, the piston rod 14 and the plunger rod 8 are integrated or separately, and the plunger tip 7 is placed in the injection sleeve at the required speed. Then you can push in the required distance.

  Thus, at the time of injection, instead of directly driving the plunger rod or the hydraulic control mechanism by the advance / retreat control mechanism, high-speed injection is performed in cooperation with the plunger rod behind the plunger rod controlled by the hydraulic control mechanism. It is a feature of the present invention that a piston rod to be realized is arranged and the advance / retreat of the piston rod is controlled by an advance / retreat control mechanism.

  In other words, the present invention is characterized in that a hybrid high-speed injection structure that combines the hydraulic control mechanism and the advance / retreat control mechanism and synergistically exhibits its effects is adopted, and this adoption makes it possible to drive the plunger rod with high accuracy. It is possible to produce a high-quality casting with a high yield.

  Further, the advance / retreat control mechanism is a mechanism that only controls the advance / retreat of the piston rod. Therefore, when the hydraulic control mechanism is advanced / retracted, or when the plunger rod is advanced / retracted (in this case, the hydraulic control mechanism for the plunger rod is ultimately also used). The advance / retreat control mechanism can be made smaller and lighter than the control unit. This point is also a feature of the present invention.

  FIG. 1 shows the ball screw mechanism 18 as one configuration of the advance / retreat control mechanism, but the advance / retreat control mechanism may be a mechanical mechanism that moves the piston rod forward or backward with good controllability, and is limited to the ball screw mechanism. Is not something The advance / retreat control mechanism may be, for example, a rack and pinion mechanism.

  Next, a basic driving mode of the device of the present invention shown in FIG. 1 will be described based on FIGS.

  FIG. 2 shows an embodiment of the apparatus of the present invention immediately before a predetermined amount of molten metal is poured from a pouring port (not shown) into the injection sleeve (see FIG. 1) and injection is started. At this time, the plunger rod 8 is retracted to the end of the hydraulic cylinder 9, and the piston rod 14 is in contact with the piston 13 of the plunger rod 8 and is on standby.

  Next, as shown in FIG. 3, the servo motor 19 is rotated in accordance with the control signal to drive the ball screw mechanism 18, and the piston rod 14 is integrated with the plunger rod 8 to advance with respect to the fixed plate at a predetermined speed. At this time, the electromagnetic opening / closing mechanism M is activated to close the high-speed valve 12, following the advance of the piston rod 14 and the plunger rod 8, supplying hydraulic oil to the oil chamber 16 </ b> H behind the piston 13, The hydraulic oil is discharged from 16R.

  The plunger rod 8 integrated with the piston rod 14 advances in the low speed injection region in the injection sleeve at a predetermined advance speed that the ball screw mechanism 18 forms and maintains.

  Then, the advance distance of the plunger rod 8 is detected by a displacement sensor (not shown), and the tip of the plunger rod 8 reaches a position where the low speed injection is switched to the high speed injection (low speed-high speed switching position S, see FIG. 3). Until then, the plunger rod 8 is advanced only by the ball screw mechanism 18.

  The forward speed of the plunger rod 8 may be kept constant until it reaches the low speed-high speed switching position S, or may be accelerated from the middle.

  When the plunger rod 8 reaches the low speed-high speed switching position S, as shown in FIG. 4, the electromagnetic opening / closing mechanism M is activated to open the high speed valve 12, and from the accumulator 11, the hydraulic oil is moved to the rear oil chamber 16H. The plunger rod 8 is advanced at a high speed. The hydraulic oil is discharged from the front oil chamber 16R.

  Even after the plunger rod 8 reaches the low speed-high speed switching position S, the ball screw mechanism 18 is continuously driven to advance the piston rod 14 and pressurize the hydraulic oil in the oil chamber 16H. With this pressurization, the forward speed of the plunger rod 8 can be further increased, and the molten metal in the injection sleeve can be filled into the mold cavity at a stable high speed. As a result, a high-quality cast product can be manufactured with a high yield.

  This is a functional feature of the device of the present invention that employs a hybrid high-speed injection structure.

  In the device of the present invention, until the plunger rod reaches the low speed-high speed switching position S, the plunger rod is integrated with the piston rod and advanced only by the advance / retreat control mechanism without driving the hydraulic control mechanism, When the plunger rod reaches the low speed-high speed switching position S, a hybrid high speed injection structure is adopted in which the hydraulic control mechanism is driven and the plunger rod is advanced at high speed in cooperation with the advance / retreat control mechanism and the hydraulic control mechanism.

  In the hybrid high-speed injection structure, the advance / retreat control mechanism only needs to have a function and capacity for advancing and retracting the piston rod integrated with the plunger rod or the piston rod alone. Further reduction in size and weight can be achieved. As a result, the entire injection device is reduced in size and weight, and the maintainability of the injection device is improved.

  Thus, it is also a structural feature in the device of the present invention that the reduction in size, weight, and improvement in maintainability have been significantly achieved.

  When the filling of the molten metal is completed, the forward movement of the plunger rod 8 is almost stopped and the head pressure rises. In the apparatus of the present invention, the advance / retreat control mechanism and the hydraulic control mechanism are continued until the increased pressure reaches a predetermined value. Drive.

  When the upper pressure increase reaches a predetermined value, as shown in FIG. 5, the high speed valve 12 is closed, the hydraulic oil in the front oil chamber 16R is connected to the discharge path, and the advance / retreat control mechanism is continuously driven, The rod 14 is advanced.

  As the piston rod 14 advances, the hydraulic oil in the rear oil chamber 16H is discharged from the discharge path, and pressure is continuously applied to the plunger rod 8, so that the plunger rod 8 further advances and the head pressure further increases. To rise.

  The advance / retreat control mechanism is continuously driven to move the piston rod 14 forward, and at the same time, the high speed valve 12 is controlled in real time by the injection pressure setting shown in FIG. 9, and the operation of the oil chamber 16H is operated as shown in FIG. The oil is accumulated in the accumulator 11. The set pressure Pm is maintained by torque control of the servo motor until the cooling time expires and die casting is completed.

  After taking out the cast product, in order to discharge the solidified material remaining in the injection sleeve, as shown in FIG. 7, the advance / retreat control mechanism is driven again, and the piston rod 14 and the plunger rod 8 are integrated and advanced.

  After discharging the remaining solidified product, as shown in FIG. 8, the hydraulic control mechanism is driven to supply the hydraulic oil to the oil chamber 16R in front of the piston 13, and the hydraulic oil is discharged from the oil chamber 16H in the rear of the piston 13. At the same time, the advance / retreat control mechanism is driven to retract the plunger rod 8 and the piston rod 14 to stand by at the position shown in FIG. 2 in preparation for the next injection.

  When supplying the hydraulic oil to the oil chamber 16R in front of the piston 13, the hydraulic oil is supplied from the pump 21 in order to compensate for the reduced amount of the hydraulic oil.

  As described above, the series of operations of the apparatus of the present invention has been described based on the drawings. Since the process of increasing the injection pressure based on the operation is different from the linear process of increasing the injection pressure in normal die casting, 9 is shown in association with the operations shown in FIGS. FIG. 9 also shows the transition of the injection speed.

  The injection speed in the apparatus of the present invention follows the same transition as the injection speed in normal die casting, but the injection pressure is different from the linear rising process in normal die casting (see the dotted line in the figure) in two stages. Will rise. This point is also a feature of the present invention.

  Under the drive mode of the advance / retreat control mechanism and the hydraulic control mechanism shown in FIG. 4, when the filling of the molten metal is completed, the forward movement of the plunger rod almost stops and the head pressure starts to rise. The drive of the advance / retreat control mechanism and the hydraulic control mechanism is continued until the upper pressure boost reaches a predetermined value (see Pm ′ in FIG. 9).

  When the upper pressure boost reaches a predetermined value and a predetermined time has elapsed (see FIG. 9), as shown in FIG. 5, the high speed valve 12 is closed to stop the hydraulic control mechanism, but the advance / retreat control mechanism is continued. To drive the piston rod 14 forward. As the piston rod 14 advances, the hydraulic oil in the rear oil chamber 16H is discharged from the discharge path, and pressure is continuously applied to the plunger rod 8, so that the head pressure rises again to the set pressure (see FIG. 9 (see Pm).

  As described above, in the apparatus of the present invention, the injection pressure can be program-controlled and increased to the set pressure Pm, so that a high-quality cast product can be manufactured with a high yield.

  2) Next, the structure shown in FIG. 10 and its driving mode will be described.

  The structure shown in FIG. 10 is basically the same as the structure shown in FIG. 10, the same components as those shown in FIG. 1 are given the same numerals as those in FIG. 1, but a part of the hydraulic circuit constituting the hydraulic control mechanism is omitted.

  The structural difference is that (i) the oil chamber 16H behind the piston 13 is provided perpendicular to the hydraulic cylinder 9, and (ii) the plunger rod 8 is retracted on the lower side wall of the oil chamber 16H. The positioning member 22 for determining the position is attached.

  Due to this structural difference, the drive mode is also different from the drive mode of the structure shown in FIG. 1 and will be described below with reference to FIGS.

  FIG. 11 shows an embodiment of the apparatus of the present invention immediately before the injection is started after pouring a predetermined amount of molten metal Me into the injection sleeve from a pouring port (not shown) (see FIG. 10). At this time, the plunger rod 8 is retracted to the rearmost end set by the positioning member 22 in the hydraulic cylinder 9, and the piston rod 14 is standing by at the top of the oil chamber 16H.

  Next, as shown in FIG. 12, the servo motor 19 is rotated in accordance with the control signal to drive the ball screw mechanism 18, and the piston rod 14 is moved downward toward the oil chamber 16H.

  At this time, since the high-speed valve 12 connected to the accumulator 11 is closed and the hydraulic oil is not supplied to the oil chamber 16H from another system circuit, the plunger rod 8 moves forward following the advance of the piston rod 14. . During the forward movement of the plunger rod 8, the hydraulic oil is discharged from the front oil chamber 16R.

  The plunger rod 8 is structurally not integrated with the piston rod 14, but its operation is integrated with the piston rod 14 and at a predetermined forward speed formed and maintained by the ball screw mechanism 18 at a low speed injection region in the injection sleeve. Will move forward.

  Then, the advance distance of the plunger rod 8 is detected by a displacement sensor (not shown), and the tip of the plunger rod 8 reaches a position where the low speed injection is switched to the high speed injection (low speed-high speed switching position S, see FIG. 3). Until then, the plunger rod 8 is advanced only by the ball screw mechanism 18 through the advance of the piston rod 14.

  The forward speed of the plunger rod 8 may be kept constant until it reaches the low speed-high speed switching position S, or may be accelerated from the middle. When accelerating from the middle, increase the rotation speed of the servo motor.

  When the plunger rod 8 reaches the low speed-high speed switching position S, as shown in FIG. 13, the electromagnetic opening / closing mechanism M is activated to open the high speed valve 12, and from the accumulator 11, the hydraulic oil is moved to the rear oil chamber 16H. The plunger rod 8 is advanced at a high speed. The hydraulic oil is discharged from the front oil chamber 16R.

  Even after the plunger rod 8 reaches the low speed-high speed switching position S, the ball screw mechanism 18 is continuously driven, the piston rod 14 is advanced downward, and the hydraulic oil in the oil chamber 16H is pressurized. With this pressurization, the forward speed of the plunger rod 8 can be further increased, and the molten metal in the injection sleeve can be filled into the mold cavity at a stable high speed. As a result, a high-quality cast product can be manufactured with a high yield. This point is the same as the driving mode of the structure shown in FIG.

  That is, in the device of the present invention shown in FIG. 10, the plunger rod 8 is structurally not integrated with the piston rod 14 but is integrated with the piston rod 14 in terms of operation, and is formed and maintained by the ball screw mechanism 18. The low-speed injection region in the injection sleeve is moved forward at the forward speed.

  After all, the drive mode of the device of the present invention shown in FIG. 10 is the same as the drive mode of the device of the present invention shown in FIG. 1, and the structure shown in FIG. 10 is also one of the hybrid high-speed injection structures.

  When the filling of the molten metal is completed, the forward movement of the plunger rod 8 is almost stopped and the head pressure rises. In the apparatus of the present invention, the advance / retreat control mechanism and the hydraulic control mechanism are continued until the increased pressure reaches a predetermined value. Drive.

  When the upper pressure increase reaches a predetermined value, as shown in FIG. 14, the high speed valve 12 is closed, the hydraulic oil in the rear oil chamber 16H is connected to the discharge path, and the advance / retreat control mechanism is continuously driven, The rod 14 is advanced.

  As the piston rod 14 advances, the hydraulic oil in the front oil chamber 16R is discharged from the discharge path, and pressure is continuously applied to the plunger rod 8, so that the plunger rod 8 further advances and the head pressure further increases. To rise.

  The advance / retreat control mechanism is continuously driven to move the piston rod 14 forward, and at the same time, the high speed valve 12 is controlled in real time according to the setting of the injection pressure shown in FIG. 18, and as shown in FIG. The hydraulic oil is accumulated in the accumulator 11. The set pressure Pm is maintained by torque control of the servo motor until the cooling time expires and die casting is completed.

  After taking out the cast product, in order to discharge the solidified material remaining in the injection sleeve, as shown in FIG. 16, the advance / retreat control mechanism is driven again to advance the piston rod 14, thereby moving the plunger rod 8 forward. Move forward.

  After discharging the remaining solidified product, as shown in FIG. 17, the hydraulic control mechanism is driven to supply the hydraulic oil to the oil chamber 16R in front of the piston 13, while the hydraulic oil is supplied from the oil chamber 16H in the rear of the piston 13. Then, the plunger rod 8 is retreated, and the advance / retreat control mechanism is driven to retreat the piston rod 14, and each of them is put on standby at the position shown in FIG. 11 in preparation for the next injection.

  When supplying the hydraulic oil to the oil chamber 16R in front of the piston 13, the hydraulic oil is supplied from the pump 21 in order to compensate for the reduced amount of the hydraulic oil.

  The series of operations of the device of the present invention shown in FIG. 10 has been described with reference to the drawings. The injection pressure based on the operations rises by real-time feedback control according to preset and programmed rise curves. This is shown in FIG. 18 in association with the operations shown in FIGS. FIG. 18 also shows the transition of the injection speed.

  As described above, according to the present invention, a high-quality cast product can be manufactured with a high yield. In addition, the present invention realizes further reduction in size and weight, and is also excellent in maintainability. Therefore, the present invention has high applicability in the die casting industry.

It is a figure which shows one structure of the hybrid high-speed injection apparatus of this invention. It is a figure which shows the aspect just before the injection start in this invention. In this invention, it is a figure which shows the aspect just before a plunger arrives at the low speed-high speed switching position S. In this invention, it is a figure which shows the aspect which a plunger rod advances at high speed. In this invention, filling of a molten metal is completed and it is a figure which shows an aspect when advance of a plunger rod has stopped substantially. In this invention, injection is completed and it is a figure which shows the aspect when advance of a plunger rod stops completely. In this invention, in order to discharge | emit the solidified substance which remains in an injection sleeve, it is a figure which shows the aspect which advances a piston rod and a plunger rod integrally. In this invention, in order to prepare for the next injection, it is a figure which shows the aspect which makes a plunger rod and a piston rod retreat. It is a figure which shows the raise progress of the injection pressure in this invention. It is a figure which shows another structure of the hybrid high-speed injection apparatus of this invention. It is a figure which shows the aspect just before the injection start in this invention. In this invention, it is a figure which shows another aspect immediately before a plunger arrives at the low speed-high speed switching position S. In this invention, it is a figure which shows another aspect which a plunger rod advances at high speed. In this invention, it is a figure which shows another aspect when filling with a molten metal is completed and the advance of a plunger rod has stopped substantially. In this invention, it is a figure which shows another aspect when injection is completed and advance of a plunger rod stops completely. In this invention, in order to discharge | emit the solidified substance which remains in an injection sleeve, it is a figure which shows another aspect which advances a piston rod and a plunger rod integrally. In this invention, in order to prepare for the next injection, it is a figure which shows another aspect which makes a plunger rod and a piston rod retreat. It is a figure which shows another rise progress of the injection pressure in this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fixed platen 2 Movable platen 3 Fixed metal mold 4 Movable metal mold 5 Mold cavity 6 Injection sleeve 7 Plunger tip 8 Plunger rod 9 Hydraulic cylinder 10 Hydraulic control mechanism 11 Accumulator 12 High speed valve 13 Piston 14 Piston rod 15 Connecting member 16R, 16H Oil chamber 17 Ball screw 18 Ball screw mechanism 19 Servo motor 20 Advance / retreat control mechanism 21 Pump 22 Positioning member M Electromagnetic switching mechanism Me Molten metal S Low speed-high speed switching position Pm, Pm 'Injection pressure

Claims (5)

In the injection device that drives the plunger and fills the mold cavity with molten metal,
A hybrid high-speed injection device with excellent controllability, wherein a piston rod controlled by an advance / retreat control mechanism is provided behind a hydraulic cylinder containing a plunger rod controlled by a hydraulic control mechanism.   The hybrid high-speed injection device with excellent controllability according to claim 1, wherein the advance / retreat control mechanism is a ball screw mechanism.   The hybrid high-speed injection device with excellent controllability according to claim 2, wherein the ball screw mechanism is driven by a servo motor. A piston rod controlled by the advance / retreat control mechanism is provided behind the hydraulic cylinder containing the plunger rod controlled by the hydraulic control mechanism, and the hydraulic control mechanism and the advance / retreat control mechanism are driven in cooperation to move the molten metal into the mold cavity. In a control method for controlling filling,
(I) The advance / retreat control mechanism is driven, and the plunger rod is integrated with the piston rod and advanced until reaching the low speed-high speed switching position.
(Ii) A hybrid high-speed injection control method characterized by driving the hydraulic control mechanism and advancing the plunger at a high speed in cooperation with the advance / retreat control mechanism.   5. The hybrid high-speed injection control method according to claim 4, wherein the drive of the hydraulic control mechanism is real-time feedback controlled according to a rising curve up to a preset injection pressure.

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