JPH08215824A - Method and device for extruding product of high pressure casting machine and the like - Google Patents

Abstract

PURPOSE: To improve the mass-productivity by quickening die opening and taking-out speed of a product without breaking a biscuit with pushing force of an injection cylinder and without withdrawing the product from a movable die, at the time of extruding the product from a high pressure casting machine, etc. CONSTITUTION: In the product extruding method in the high pressure casting machine for extruding the product from a fixed die with the injection cylinder 12 by executing the die opening with a die opening/closing cylinder 5, at the time of extruding the product, the cylinder is driven with a prescribed thrust or pressure while supplying so sufficient flow rate of working oil as to obtain the speed of the die opening/closing cylinder 5 to the speed of the injection cylinder 12 or higher, and the injection cylinder 12 is driven with the speed control or the flow rate control. Further, in the product extruding device in the high pressure casting machine for extruding the product from the fixed die with the injection cylinder 12 by executing the die opening with the die opening/closing cylinder 5, at the time of extruding the product, the cylinder is driven with the prescribed thrust or pressure while supplying so sufficient flow rate of the working oil as to obtain the speed of the die opening/closing cylinder 5 to the speed of the injection cylinder 12 or higher, and the injection cylinder 12 provides a control means for driving with the speed control or the flow rate control.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-pressure casting machine or the like for injection-molding aluminum, for pushing out an injection-molded product when the movable mold is retracted and opened to take out the injection-molded product from the mold. And a device for performing the method.

[0002]

2. Description of the Related Art Generally, the production of cast products by injection molding is
An injection molding apparatus as shown in FIGS. 7 and 8 is used. First, a predetermined amount of molten metal, which is a molten metal, is poured into the injection sleeve 21, and the molten metal is held by the fixed die 1 with the plunger tip 22.
2 and the movable mold 13 are press-fitted into a cavity 15 formed between the mold 11 and the molten metal filled in the cavity 15 to be cooled and solidified to form a product 27, and then the movable mold 13 is moved. The mold 17 is retracted together with the board 17 to open the mold, then the molded product 27 is taken out from the movable mold 13, and after cleaning the mold 11, applying a release agent, etc., the movable mold 13 and the fixed mold. The mold is clamped so as to be aligned with 12, and the molten metal is again press-fitted into the cavity 15, and injection molding is repeated.

In order to improve the mass productivity in the above injection molding, various attempts have been made to reduce the cycle time from the press-fitting of the molten metal to the mold clamping, which is the next press-fitting preparation.

In order to shorten the cycle time, the shapes of the fixed mold 12, the movable mold 13 and the cavity 15 are modified in order to shorten the chill time, which is a cooling and solidifying step of the molten metal, and the mold is opened and the product is opened. The efficiency of taking out, cleaning of the mold 11, application of a release agent, and the like is improved.

As described above, in order to shorten the cycle time, it has been attempted to shorten the chill time, which is the cooling period of the molten metal, and shorten the time in the steps such as mold opening, cleaning, and mold clamping, but the chill time is shortened. In the above, if the chill time is too short, cooling and solidification of the molten metal will be insufficient,
There is a drawback that the product is deformed in the process of taking out the product from the movable mold 13 and further in the cooling and processing process after taking out. Further, when the mold is opened, as shown in FIG. 8, the plunger tip 22 is moved forward with the backward movement of the movable mold 13 so that the remaining hot water in the injection sleeve 21 is solidified in the biscuit 29.
If the product is not properly synchronized with the die opening / closing device and the plunger tip of the injection sleeve when pushing out the injection sleeve 21, the biscuit thickness will vary due to variations in the hot water supply amount in each casting, and the molten metal inside the biscuit When not solidified, the moving speed of the plunger tip is fast, and when the biscuit is extruded with a strong ejection force, the biscuit breaks and the molten metal inside scatters and scatters.
The scattered molten metal may adhere to the mating surface of the mold, making subsequent casting difficult. On the contrary, if the mold opening is faster, the product will come out of the moving mold, and it will take a lot of time to take out the product in the next step.

As a countermeasure, for example, Japanese Patent Publication No. 3-378.
As shown in No. 28, the mold opening speed is detected, the forward speed of the plunger tip is controlled so as to be equal to the mold opening speed, and the hydraulic pressure of the injection cylinder is detected to try to keep the value below the set value. Technology and JP-A-3-2343
As shown in No. 44, by limiting the sending hydraulic pressure of the injection cylinder to the set extremely low pressure or less, the plunger chip of the injection cylinder controls the maximum force of pushing the biscuit, and the pressure on the mold opening side is mainly used. , A technique of releasing the product from the fixed mold part and extruding the biscuit has been proposed.

[0007]

In the former (Japanese Patent Publication No. 3-37828) shown in the above-mentioned prior art, the opening of the injection control valve is changed by the deviation between the mold opening displacement and the displacement of the plunger tip of the injection cylinder. Since they are controlled and synchronized, the deviation is small at the beginning of the mold opening movement, so that the beginning of the injection cylinder's movement is delayed and synchronization cannot be achieved, and the mold opening becomes too fast. Further, since the toggle type mold opening / closing means is used, even if the flow rate is constant, the mold opening speed gradually increases due to the characteristics of the toggle mechanism, and a deviation remains in the feedback control, which makes it difficult to perform synchronization.

On the other hand, when the tuning becomes improper, the pressure of the injection cylinder is made smaller than the set value to prevent the plunger tip of the injection cylinder from becoming faster at least. Since the pushing force of the changes greatly depending on the amount of hot water supplied, it is difficult to set the above set value to an appropriate value, and the valve used has only a meter-in flow rate control function and does not have a pressure reducing function. However, the pressure control cannot be smoothly performed, and the control must be a large vibration. In addition, no consideration is given to measures against the mold opening speed being higher than the plunger tip speed and the product coming off the moving mold.

The latter shown in the above-mentioned prior art (Japanese Patent Laid-Open No. 3-23)
No. 4344), the pushing force of the biscuit due to the operation of the injection cylinder greatly changes depending on the amount of hot water supplied, and it has been clarified how to set the extremely low pressure setting value of the hydraulic pressure of the injection cylinder. However, since there are advantages and disadvantages depending on how to set the setting value, and there is no indication as to which value to set specifically considering the extrusion resistance of the biscuit, the setting of that value is practical. Is extremely difficult.

Immediately before the extrusion of the biscuit is completed, the extrusion resistance becomes small and finally becomes zero.
Even at this time, the working force of the injection cylinder is directly applied to the biscuit even at an extremely low pressure, and all the working force acts as a pressing force on the biscuit, which increases the possibility of breaking the biscuit.

Further, since the valve used has only a meter-in flow rate control function and does not have a pressure reducing function, the pressure control is extremely difficult and the control of vibration is large, as in the former prior art. At the same time, there is a drawback that the pressure control is theoretically impossible when the speed gradually decreases and finally becomes zero.

Therefore, according to the present invention, when a product is extruded from a high pressure casting machine or the like, the biscuit is not destroyed by the pushing force of the injection cylinder, and the product does not come out from the moving mold, and the mold opening and the product are prevented. The purpose is to increase the take-out speed and improve mass productivity.

[0013]

In order to solve the above-mentioned problems, the present invention provides a product extrusion method of a high-pressure casting machine in which a mold opening / closing cylinder is used for mold opening, and an injection cylinder is used to extrude a product from a fixed mold. At some times, the cylinder is driven by a predetermined thrust or pressure while supplying hydraulic fluid of a sufficient flow rate to the mold opening / closing cylinder at a speed higher than that of the injection cylinder, and the injection cylinder is driven by speed control or flow rate control. In a product extrusion device of a high-pressure casting machine in which a mold is opened by a mold opening / closing cylinder and a product is extruded from a fixed mold by an injection cylinder, a speed higher than the speed of the injection cylinder relative to the mold opening / closing cylinder during product extrusion. The cylinder is driven with a predetermined thrust or pressure while supplying hydraulic fluid at a flow rate sufficient to achieve Those having a control means for driving by the amount control.

The present invention is also characterized in that the mold opening / closing device is driven by a thrust or pressure corresponding to the weight or sliding resistance of the movable die, and the thrust corresponding to the weight or sliding resistance of the movable die. Or, add the thrust or pressure equivalent to the force to push the product from the moving die to the pressure and the thrust or pressure equivalent to the force to push the product from the fixed die and the force to push the biscuit. It is characterized by driving the mold opening and closing device with the smaller one of the above values as the maximum value, and when the mold opening and closing cylinder starts the mold opening,
At the same time or shortly thereafter, extrusion of the product is started by the injection cylinder.

The present invention is also characterized in that the thrust or pressure of the mold opening / closing cylinder at the time of mold opening is set such that the maximum value is (a) and the minimum value is (b) below. To do. (A) A value obtained by adding a thrust or pressure equivalent to the force obtained by adding the force for pushing out the product from the movable die and the force for pushing out the biscuit to the thrust or pressure corresponding to the weight or sliding resistance of the movable die. The smaller value. (B) A thrust force or a pressure corresponding to the weight or sliding resistance of the movable die part when hydraulic oil is supplied to the die open / close cylinder during the synchronous operation of the die open / close cylinder and the injection cylinder.

[0016]

Since the present invention is configured as described above, when the product is extruded by the high-pressure casting machine, the mold opening / closing cylinder is operated to move the movable mold, and the injection cylinder is operated to move the product in the moving direction of the movable mold. When pressing and pushing the product against the movable mold while pushing it out from the fixed mold, the hydraulic oil is supplied to the mold opening / closing cylinder at a flow rate sufficient to be higher than the speed of the injection cylinder. The mold opening / closing cylinder is driven with a predetermined thrust or pressure by adjusting the pressure of the injection cylinder, while the injection cylinder is driven by speed control or flow rate control, so that the biscuit in the fixed mold is acted on by the injection cylinder to cause excessive pressure. It prevents the biscuits from being broken and the molten metal to scatter, and prevents the product from coming out of the moving mold due to too little extrusion force of the injection cylinder. It is.

[0017]

An embodiment of the present invention will be described with reference to the drawings.
In FIG. 1 and FIG. 2, a vertical high-pressure casting machine 1 for injection-molding aluminum has a fixed die 4 as a lower die fixed on a fixed platen 3 installed on a fixed base 2. On the other hand, a movable mold 7 as an upper mold is fixed to the lower part of a slide 6 which moves up and down by a mold opening / closing cylinder 5 so as to face it.

An injection space 8 is formed between the mating surfaces of the movable mold 7 and the fixed mold 4, and a runner 10 communicating with the injection space 8 is connected to the lower mold 4 and the runner 10 A sleeve 11 provided on the fixed platen 3 communicates with the. Sleeve 11
An injection plunger 13 of an injection cylinder 12 is slidably inserted into the injection cylinder 13, and a plunger tip 14 is fixed to the tip of the injection plunger 13.

In the left and right die opening / closing cylinders 5, the lower chamber 16 of the piston 15 is provided with an electromagnetic proportional directional flow control valve (hereinafter referred to as an electromagnetic proportional valve) 1 via a pilot check valve 17.
8 and the upper chamber 20 communicates with the B port of the same solenoid proportional valve 18. The electromagnetic proportional valve 18 has a P (pressure source) port and a T (tank) port facing the A port and the B port, and the electromagnetic proportional valve 18 has three switching positions on the circuit diagram and has a first position 21. Connects the P port with the A port and the B port with the T port, the second position 22 blocks the connection of each port, and the third position 23 connects the P port with the B port.
The port, the T port and the A port are communicated with each other, and the electromagnetic actuators on both sides control the flow rate by switching the direction and controlling the opening degree of the valve by a signal from the control device 19.

The T port of the solenoid proportional valve 18 is opened to the tank, and the P port communicates with a pump device in which a small flow main pump 24 and a large flow speed increasing pump 25 are arranged in parallel. An electromagnetic proportional relief valve 2 is provided in the discharge passage of the main pump 24.
6 is provided, and the discharge pressure is controlled by a signal from the control device 19. Further, a relief valve 27 with an electromagnetic unload is provided in the discharge passage of the speed increasing pump 25.

In the lower chamber 29 of the piston 28 of the injection cylinder 12, a flow rate control valve (hereinafter referred to as an electromagnetic proportional flow rate control valve with pressure compensation or a digital flow rate control valve with pressure compensation, which will be described later) is provided via a pilot check valve 30. , Which is referred to as a flow rate proportional valve) 31 and communicates with the A port of the switching valve 32, and the upper chamber 33 communicates with the B port of the switching valve 32. The switching valve 32 has a P port and a T port facing the A port and the B port, and is switched to three positions of a first position 34, a second position 35, and a third position 36 by solenoids on both sides of the switching valve 32. First position 34 is A port and P
Port 2 and port B and T are in communication, second position 35
Connects the A port and the B port to the T port and blocks the P port, and the third position 36 connects the P port to the T port and the B port to the P port. The T port communicates with the tank,
The P port communicates with a hydraulic source such as a pump via an accumulator 37 and a check valve.

The forward flow side port of the pilot check valve 30 communicating with the lower chamber 29 of the injection cylinder 12 and the switching valve 32.
A parallel circuit of a check valve 38 and a flow rate control valve 31 is connected between the A ports of the flow rate control valve 31 and the flow rate control valve 31 is, as is well known, an electromagnetic flow rate control valve 40, a pressure compensation valve 42, and a pilot pressure reducing valve 41. The flow rate can be set from zero to an arbitrary flow rate by a signal from the control device 19.

In the control device 19, the signal from the injection plunger position detector 44 fixed to the injection plunger 12
Various signals such as a slide position detector (not shown) are input, and a solenoid proportional valve 18, a solenoid relief valve 26,
A variable control signal is output to the flow control valve 31, and a switching operation signal is output to valves such as the switching valve 32.

[0024] In the above apparatus, when injection molding is performed,
The solenoid proportional valve 18 is switched to the third position 23 side, and the main pump 2
4 and the speed increasing pump 25 are operated to supply pressure oil to the upper chamber 20 of the mold opening / closing cylinder 5, and a solenoid proportional valve is controlled by a control signal from the controller 19 corresponding to the set speed corresponding to the position of the moving mold 7. 18 controls the flow rate.

After the movable mold 7 is lowered to close the mold, the half nut 46 arranged on the upper part of the slide 6 is engaged with the thread portion of the tie rod 47 to fix the rod 49 of the mold clamping cylinder 48 fixed to the slide 6. Is extended by hydraulic pressure and applied to the half nut 46 to perform mold clamping.

Then, the switching valve 32 is switched to the first position 34, and the flow rate of the pressure oil from the accumulator 37 is controlled by the flow rate control valve 31 so that the injection speed corresponding to the position of the injection plunger is performed, and the injection cylinder 12 is charged. Lower chamber 29
Supply pressure oil to. When the filling of the molten metal is completed, the pressure control valve (not shown) operates from the speed control while controlling the pressure increasing piston 43 to increase the head pressure of the injection cylinder, and the high pressure is applied to the molten metal to prevent the formation of the shrinkage cavity at the time of solidification. Prevent occurrence.

Most of the molten metal that has been injected will solidify after the elapse of a predetermined time. At this time, the injection sleeve 11
The molten metal that has not been injected remains from the runner 10 to the runner 10 and solidifies to form the biscuit 50 integrally with the product 51. This biscuit has a different thickness due to the different amount of molten metal injected into the injection sleeve before each injection operation,
Therefore, the solidified state of the biscuit 50 may be changed randomly every time, and the unsolidified molten metal may be contained inside the biscuit 50. If the molten metal is allowed to stand for a time sufficient to completely solidify without performing the next step, mass productivity is significantly impaired. Therefore, when the set time for the surface of the biscuit 50 to appropriately solidify has elapsed, the mold is opened next and the process of product extrusion is started.

In the process of mold opening and product extrusion, the control device 19 sets the electromagnetic proportional relief valve 26 to a predetermined pressure, switches the electromagnetic proportional valve 18 to the first position 21, and discharges the speed increasing pump 25. The electromagnetic switching relief valve 27 is switched to the unload state, and the pressure oil is supplied only by the small capacity main pump 24. The flow rate of this pressure oil can be controlled by the solenoid proportional valve 18, or the maximum value can be limited by the discharge amount of the main pump 24.

At this time, the set pressure P of the electromagnetic proportional relief valve 26 is set such that the weight of the product is sufficiently smaller than that of the slide 6 and the moving die 7, and as shown in FIG. The total weight of the object to be lifted when the mold is opened (hereinafter referred to as the weight of the upper mold, etc.) is W, the resistance of the product 51 to separate from the upper mold 7 is F ₁ , and the resistance of the product 51 to separate from the lower mold 4 is F _2. Assuming that the resistance of the biscuit part of the lower mold 4 to separate from the mold is F ₃ and the head side area of the mold opening / closing cylinder is A,
For example, A × P ≦ W, that is, from P ≦ W / A, P = W /
When it is set to A, the maximum capacity of the mold opening / closing cylinder is the ability to lift the weight of the upper mold, etc., but the product does not come off from the lower mold due to the separation resistance between the product and the mold. That is, the slide and upper die do not rise

Further, based on such an idea, A × P ≦ W + F ₂ + F _{3, that} is, P ≦ (W + F ₂ + F
₃ ) / A to P in a range smaller than (W + F ₂ + F ₃ ) / A,
When the product and the biscuit are not pulled out from the upper mold by approaching this value as much as possible, the product and the biscuit are pulled out from the lower mold with a slight force afterward. Therefore, it is possible to push out the product and the biscuit from the lower mold by pressing the biscuit by the operation of the injection cylinder, as will be described later, only the amount of the force, and the force becomes the minimum, It will not exert excessive force. However, A × P> W + F ₂ + F _{3, that} is, P> (W + F ₂ + F
_{If the} relief pressure is set to ₃ ) / A, the product will be pulled out from the lower mold only by raising the upper mold by the mold opening / closing cylinder, so if the biscuit cannot be smoothly pulled out from the lower mold, Too much tensile force will be generated and it will be damaged.

On the other hand, A × P ≧ W + F _{1, that} is, P ≧
When the set pressure of the electromagnetic proportional relief valve is set to be (W + F ₁ ) / A, the product comes out of the upper mold and remains in the lower mold, which makes it extremely difficult to take out the product. Therefore, it is necessary that A × P <W + F _{1, that} is, P <(W + F ₁ ) / A.

As a result, the set pressure of the electromagnetic proportional relief valve, that is, the maximum value of the thrust or pressure of the mold opening / closing cylinder, pushes the product from the movable die to the thrust W or pressure corresponding to the weight of the movable die part. Either a value obtained by adding thrust F ₁ or pressure equivalent to force or a value obtained by adding thrust or pressure equivalent to force obtained by adding force F _{2 for} extruding the product from the fixed mold and force F ₃ for extruding the biscuit It is desirable to set the smaller value to the maximum value. Such pressure setting can be arbitrarily set by the input current as shown in FIG. Alternatively, in order to improve the accuracy of the set pressure, the pressure may be measured by a sensor and the pressure of the electromagnetic proportional relief valve may be feedback-controlled.

Simultaneously with the operation of the mold opening / closing cylinder 5 as described above, or after a minute time when the operation is stabilized, the set flow rate of the flow control valve 31 is set to be slightly smaller than the discharge amount of the main pump 24, and the injection is performed. The cylinder speed does not exceed the lifting cylinder speed and the biscuit is not broken by the operation of the injection cylinder, and the switching valve 32 is switched to the first position 34 to raise the injection plunger 13 of the injection cylinder 12. Due to the operation of this injection cylinder, a pushing force is added under the condition that the upper mold cannot move due to the mold separation resistance even if the upper mold is lifted by the operation of the mold opening / closing cylinder as described above, so that the product and the biscuit are Start to get out of the lower mold.

After that, the injection cylinder moves up at a constant speed by the flow rate control of the flow rate control valve 31, and at this time, the rising speed at the time of opening the mold of the lifting cylinder and pushing out the product is the main pump 2
Since the discharge amount of No. 4 is larger than the control flow rate of the flow control valve 31, the mold opening / closing cylinder can follow the rise of the injection cylinder, and the pressure in the mold opening / closing cylinder is maintained at a predetermined pressure by the electromagnetic relief valve. , Both cylinders can perform mold opening and product extrusion in a completely synchronized state.

[0035] Mold Opening and the product extrusion progresses so as to above, leaving the resistance F ₂ between the product and the lower mold, the withdrawal resistance F ₃ biscuits portion gradually decreases and finally becomes zero.
At this time, since the mold opening / closing cylinder shares a constant thrust or pressure, the thrust of the injection cylinder decreases as the mold opens and product extrusion proceeds as described above, and finally becomes zero at the end of the process. Has become.

As described above, during the mold opening, the excess of the flow rate is relieved from the electromagnetic relief valve on the elevating side, but W + F
_{When 2} + F ₃ becomes gradually smaller and becomes less than the thrust or pressure of the mold opening and closing cylinder, the relief flow rate from the electromagnetic relief valve decreases, the flow rate flowing to the mold opening and closing cylinder increases and the rising speed increases and the constant speed Synchronized with the rising injection cylinder, the mold is opened and the product is pulled out only by the lift cylinder. After that, the injection cylinder continues to rise, but does not push the biscuit.

Considering the above operation from the viewpoint of the operation characteristics of the electromagnetic relief valve 16, as shown in FIG. 5, when the relief valve having the maximum set value P ₀ sets P ₂ by electromagnetic control, As described above, P ₁ , which is the smaller value of (W + F ₁ ) / A and (W + F ₂ + F ₃ ) / A,
The pressure is set to a value between P ₄ which is the value of W / A in consideration of the weight or sliding resistance of the movable die part, which is capable of raising the uppermost die. As a result, a relief valve having the characteristic of the curve Y in the figure is obtained, and naturally the pressure P ₃ of the die opening / closing cylinder in the state of operating in synchronization with the injection cylinder as described above during the operation of the die opening / closing cylinder is naturally P ₁
It has a pressure of P ₃ than P ₂ is a small pressure at a pressure between P ₄ and. At this time, the flow rate Q ₃ on the curve Y corresponding to the pressure of P _3, the flow rate in the drawing q ₁ is relieved from the relief valve.

The mold opening / closing cylinder and the injection cylinder operate as described above, the injection cylinder stops at a predetermined stroke position, and the switching valve 32 is switched to the third position 36 and lowered. On the other hand, in the mold opening / closing cylinder, the set value of the electromagnetic proportional relief valve is raised to the rated value P ₀ at a predetermined position, the electromagnetic switching relief valve 27 of the increasing pump 25 is turned on, and the opening degree of the electromagnetic proportional valve 18 is increased. Then, the amount of oil supplied is increased to increase the speed of the mold opening / closing cylinder, and the upper mold is rapidly raised to a predetermined height. Then, the product is taken out from the upper mold, and one step is completed.

Although the flow control valve and the switching valve are used in the control device of the injection cylinder in the above-mentioned embodiment, the control valve is composed of a high response proportional valve or a servo valve as shown in FIG. 6, for example. The injection control valve 55 may be used. This injection control valve is, for example, Japanese Patent Application No. 5-
Like the throttle switching control valve of No. 88689, it is a highly responsive control valve capable of continuously controlling the opening degree, and a control system capable of flow rate control and pressure control is constituted by a single valve. For example, at the position of 56a, the flow rate to the injection cylinder is metered in by the opening degree from P to A, and metered out by the opening degree from B to T, so that arbitrary flow rate control is possible. At the position of 56b, the opening from P to A and A
By controlling the relationship of the opening degree from T to T, the pressure at the A port, that is, the pressure on the head side of the injection cylinder can be controlled.

The speed of the injection cylinder is subjected to speed feedback control or learning control by the control device 19 according to a preset pattern by the signal of the injection cylinder position sensor and the speed signal obtained by processing the signal.
As for the head pressure of the injection cylinder, it goes without saying that the pressure feedback control is performed by the control device 19 according to a preset pattern by detecting the head pressure of the injection cylinder with the pressure sensor 57.

The type of the high-pressure casting machine has been described as the vertical type, but of course the horizontal type also functions similarly. In that case, it goes without saying that the weight of the movable die portion corresponds to the sliding resistance of the movable die portion.

[0042]

Since the present invention is constructed and operates as described above, when a product is extruded from a high-pressure casting machine or the like, a constant force acts on the product from the mold opening / closing cylinder through the moving mold part, and is also necessary. Since the product pushing force is made to act from the injection cylinder, it is possible to respond to the fluctuation of the extrusion resistance of the biscuit part due to the amount of hot water supply only by the force from the injection cylinder. Also, since the force required for mold opening is not applied from the injection cylinder,
No extra force is applied to the biscuit, and the biscuit is not destroyed and the molten metal inside is not scattered. Furthermore, the mold opening / closing cylinder moves by the same amount as the biscuit portion is pushed out by the injection cylinder, and both can operate in perfect synchronization, and in this process too much force is prevented from acting on the biscuit portion. Not only can this be done, but the product does not fall out of the moving mold, making it difficult to remove the product. Further, as the product extrusion progresses and the extrusion resistance decreases, the extrusion force by the injection cylinder decreases and the speed of the mold opening / closing cylinder increases, so that the operating efficiency of the high pressure casting machine can be improved.

Further, in the inventions of claims 2 and 7, the pushing force by the injection cylinder is a value limited by the pushing resistance of the biscuit and the releasing resistance of the product from the fixed mold, and the pushing force is excessive. Can be prevented.

Further, in the inventions of claims 3 and 8, a larger force can be applied from the mold opening side, and the pushing force by the injection cylinder is limited to the minimum necessary value, which is excessive. The generation of extrusion force can be better prevented.

Further, in the inventions according to claims 4 and 9, it is possible to completely eliminate the non-synchronization of the start of product extrusion by the mold opening / closing cylinder and the injection cylinder, and the excessive extrusion force of the biscuit and the upper die. It is possible to prevent the product from coming off.

Further, in the fifth and tenth aspects of the present invention, the optimum setting can be performed among the various settings, and the above trouble can be completely eliminated.

[Brief description of drawings]

FIG. 1 is a hydraulic circuit diagram of an embodiment of the present invention.

FIG. 2 is a side view showing a partial cross section of the high-pressure casting machine according to the embodiment of the present invention.

FIG. 3 is a partial cross-sectional view showing the acting force when the mold is opened.

FIG. 4 is an input current-pressure characteristic diagram of the electromagnetic relief valve in the hydraulic circuit diagram shown in FIG.

FIG. 5 is an operating characteristic diagram of the electromagnetic relief valve of the same.

FIG. 6 is a hydraulic circuit diagram of another embodiment of the present invention.

FIG. 7 is a partially sectional front view of a conventional injection molding device.

FIG. 8 is a partial cross-sectional front view of the conventional movable mold retracted similarly to FIG. 7.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... High-pressure casting machine, 2 ... Fixed base, 3 ... Fixed board, 4 ... Fixed mold, 5 ... Mold opening / closing cylinder, 6 ... Slide, 7 ... Moving mold, 8 ... Injection space, 10 ... Runner, 11 ... Sleeve, 12
... injection cylinder, 13 ... injection plunger, 14 ... plunger tip, 15 ... piston, 16 ... lower chamber, 17 ... check valve, 18 ... electromagnetic switching servo valve, 19 ... control device,
20 ... Upper chamber, 21 ... First position, 22 ... Second position, 23
... 3rd position, 24 ... main pump, 25 ... accelerating pump, 2
6 ... Electromagnetic proportional relief valve, 27 ... Electromagnetic switching relief valve,
28 ... Piston, 29 ... Lower chamber, 30 ... Check valve, 3
1 ... Electromagnetic flow control valve with pressure compensation, 32 ... Switching valve, 33 ...
Upper chamber, 34 ... First position, 35 ... Second position, 36 ... Third
Position, 37 ... Accumulator, 38 ... Check valve, 40
… Electromagnetic flow control valve, 41… Pilot pressure relief valve, 4
2 ... Pressure compensation valve 43 ... Booster piston, 44 ... Position detector, 46 ... Half nut, 47 ... Tie rod, 48 ... Mold clamping cylinder, 4
9 ... Rod, 50 ... Biscuit, 51 ... Product.

Claims (10)

[Claims] 1. In a product extrusion method of a high-pressure casting machine in which a mold is opened by a mold opening / closing cylinder and a product is extruded from a fixed mold by an injection cylinder, when the product is extruded, a speed equal to or higher than the speed of the injection cylinder with respect to the mold opening / closing cylinder. A method for extruding a product such as a high-pressure casting machine, characterized in that the cylinder is driven by a predetermined thrust or pressure while supplying a sufficient amount of hydraulic oil to make it, and the injection cylinder is driven by speed control or flow rate control. 2. The method for extruding a product such as a high-pressure casting machine according to claim 1, wherein the mold opening / closing device is driven by a thrust or a pressure corresponding to the weight or sliding resistance of the movable mold part. 3. A value obtained by adding a thrust or pressure corresponding to the weight or sliding resistance of the movable die part to a thrust or pressure equivalent to the force for extruding the product from the movable die and the force for extruding the product from the fixed die. 3. The product extruding method for a high-pressure casting machine or the like according to claim 1 or 2, wherein the smaller value of the values obtained by adding the thrust force equivalent to the force for pushing the biscuits and the pressure or the value obtained by adding the pressure is the maximum value. 4. A mold opening / closing cylinder starts mold opening,
The product extrusion method for a high-pressure casting machine or the like according to any one of claims 1 to 3, wherein extrusion of the product is started by an injection cylinder at the same time or immediately thereafter. 5. The high-pressure casting according to claim 1, wherein the thrust or pressure of the mold opening / closing cylinder when the mold is opened is set such that the maximum value is (a) below and the minimum value is (b) below. How to push products such as machines. (A) A value obtained by adding a thrust or pressure equivalent to the force obtained by adding the force for pushing out the product from the movable die and the force for pushing out the biscuit to the thrust or pressure corresponding to the weight or sliding resistance of the movable die. The smaller value. (B) A thrust force or a pressure corresponding to the weight or sliding resistance of the movable die part when hydraulic oil is supplied to the die open / close cylinder during the synchronous operation of the die open / close cylinder and the injection cylinder. 6. A product extrusion device of a high-pressure casting machine in which a mold opening and closing cylinder is used to open a mold and an injection cylinder is used to extrude a product from a fixed mold. A high-pressure casting machine characterized by being provided with a control means for driving the cylinder with a predetermined thrust or pressure while supplying hydraulic fluid at a sufficient flow rate for the injection cylinder, and the injection cylinder being driven by speed control or flow rate control. Product extrusion equipment. 7. A product extruding device such as a high-pressure casting machine according to claim 6, wherein the mold opening / closing device is driven by thrust or pressure corresponding to the weight or sliding resistance of the movable mold part. 8. A value obtained by adding a thrust force or pressure equivalent to the force for extruding the product from the movable die to the thrust force or pressure equivalent to the weight or sliding resistance of the movable die part, and the force for extruding the product from the fixed die. The product extruding device for a high-pressure casting machine or the like according to claim 6 or claim 7, wherein a smaller value of the values obtained by adding a corresponding thrust force to which the biscuit is extruded or a pressure is added, whichever is smaller. 9. A product extruding apparatus such as a high-pressure casting machine according to claim 6, wherein the mold is opened by the mold opening / closing cylinder and the product is extruded by the injection cylinder at the same time or immediately thereafter. 10. The high pressure casting according to claim 6, wherein the thrust or pressure of the mold opening / closing cylinder at the time of mold opening is set such that the maximum value is (a) and the minimum value is (b) below. Product pushing equipment such as machines. (A) A value obtained by adding a thrust or pressure equivalent to the force obtained by adding the force for pushing out the product from the movable die and the force for pushing out the biscuit to the thrust or pressure corresponding to the weight or sliding resistance of the movable die. The smaller value. (B) A thrust force or a pressure corresponding to the weight or sliding resistance of the movable die part when the hydraulic oil is supplied to the die open / close cylinder during the motive operation of the die open / close cylinder and the injection cylinder.