JPH0354898Y2 - - Google Patents

Description

[Detailed Description of the Invention] "Industrial Application Field" The present invention relates to a multifunctional molding machine that can arbitrarily select various molding functions when molding a molten resin by injecting it into a mold cavity.

"Conventional Technology" Conventionally, single-function molding machines have often been used to inject molten resin into the cavity of a mold. In other words, an injection molding machine that provides a cavity with a fixed volume in a mold and injects an equal amount of molten resin into the mold, or an injection molding machine that injects an equal amount of molten resin into a cavity with a fixed volume and then injects a part of the cavity. Molding that is used only for a single function, such as an injection compression molding machine that narrows the cavity using the piston of a cylinder device, or a simple pressure molding machine that narrows the cavity and pressurizes it after injecting a certain volume of molten resin into a cavity of a certain volume or more. It was hot on the machine.

``Problems to be Solved by the Invention'' The above-mentioned conventional molding machines are used for molded products suitable for each single function. That is, there are two types of molded products: thick and thin, and among these, there are those with high molding accuracy and those with low molding accuracy, and those in which internal distortion is allowed to occur and those in which it is not. The injection molding machines mentioned above are suitable for molding thin products at high cycles, but the molding accuracy is low (transferability is poor), and the injection compression molding machines improve molding accuracy and have less internal distortion, but molding takes time. For example, simple pressure molding machines are suitable for thick materials, but not for thin materials, making it almost impossible to use them for multiple functions.

"Purpose of the invention" The purpose of the invention is to eliminate these drawbacks and provide a multifunctional molding machine that can perform various multifunctional moldings with one molding machine.

"Means and effects for solving the problem" The configuration of the present invention is that a lower mold is fixed to the upper surface of a fixed plate installed horizontally on the molding machine, and a movable plate that can be raised and lowered faces the fixed plate from above. Fix the upper mold on the bottom surface, and move the movable plate to the fixed plate.
A mold clamping cylinder is provided that can freely control the mold clamping force applied toward the target and its holding time, and an injection cylinder is provided below the fixed plate to inject molten resin into the cavity formed by the upper mold and the lower mold. A main cylinder is provided that can freely control the stroke of the plunger that advances and retreats into the cylinder chamber of the injection cylinder, the injection force that urges the plunger, and its holding time, and its tip communicates with the cylinder chamber of the injection cylinder.
A plasticizing cylinder is provided which is supplied with raw material resin, feeds it toward the tip, heats and plasticizes it, and sends the required amount of molten resin to the injection cylinder, and the flow path between the injection cylinder and the plasticizing cylinder is provided with a plasticizing cylinder. A valve that closes toward the cylinder and can be freely controlled to open and close is provided, and a shut-off valve is provided in the flow path between the tip of the injection cylinder and the lower mold to prevent backflow of molten resin, and the piston rod is located on the lower surface of the fixed plate. An upper mold position control cylinder is provided that penetrates through the fixed plate and comes into contact with the lower surface of the upper mold, pushing up the upper mold against the mold clamping force of the mold clamping cylinder and freely controlling the height position of the upper mold relative to the lower mold. It is characterized by: Therefore, when performing injection molding of molten resin, the mold clamping cylinder, the upper mold position control cylinder, and the main cylinder can be freely controlled and used for various molding functions.

"Example" FIG. 1 shows the structure of a multifunctional molding machine 1 of the present invention. Fixed plate 2 fixed horizontally
Tie rods 4 are erected at each of the four corners of the base plate 3 and the base plate 3 is provided above and facing each other to securely fix the base plate 3. A mold 6 consisting of an upper mold 6A fixed to the lower surface of a movable plate 5 that is guided by a tie rod 4 and can be raised and lowered, and a lower mold 6B fixed to the upper surface of the fixed plate 2.
When combined, they form a cavity 7 for molding a molded product.

The movable plate 5 is connected to a piston rod of a mold clamping cylinder 8 provided downward on the upper surface of the base plate 3, and moves up and down by supplying and discharging pressure oil to the upper and lower cylinder chambers of the piston 8A, and then moves up and down to supply and discharge pressure oil to the upper and lower cylinder chambers of the piston 8A, and to absorb the hydraulic pressure supplied to the upper cylinder chamber 8B. A mold clamping force is applied to the mold 6 according to the amount. Fit into the hole of the fixed plate 2 from the bottom side, and connect the nozzle 9A and the lower mold 6.
A pressed injection cylinder 9 is provided at the entrance of the cavity 7 of B. Cylinder chamber 9 of injection cylinder 9
A shutoff valve 9C is provided in the passage between B and the nozzle 9A to prevent backflow of the molten resin injected from the nozzle 9A. A hole 9D having a smaller diameter opens downward from the cylinder chamber 9B.

A main cylinder 10 is provided below the injection cylinder 9 in the vertical direction, and a plunger 11 connected to the piston 10A is inserted into the cylinder chamber 9B through a hole 9D. Plunger 11 is piston 10
The pressure of the pressure oil supplied to the cylinder chamber 10B on the lower side of A increases, and an injection force corresponding to the pressure is given to the molten resin, and the pressure of the molten resin supplied to the cylinder chamber 9B of the injection cylinder 9 increases. descend. Position sensor 1 is attached to the piston rod below the piston 10A.
2 sliders 12A are provided, and the plunger 1 is moved from the slider 12A depending on the position of contact with the stator 12B.
1 position signal is transmitted. Therefore, the plunger 11
The stroke of the molten resin can be freely controlled, and the amount of suction and injection of molten resin can be freely controlled.

A left-right plasticizing cylinder 13 is provided on the right side of the injection cylinder 9. This cylinder chamber 1
3A has an opening on the right side, and a screw 15 driven by a hydraulic motor 14 that seals the opening is inserted into the cylinder chamber 13A. The flow path 13B on the left side of the cylinder chamber 13A is the cylinder chamber 9B of the injection cylinder 9.
A valve 16 that connects to the lower part and closes toward the plasticizing cylinder 13 is provided in the middle, and this valve 1
Hydraulic cylinder 17 that opens 6 with a spring and closes with hydraulic pressure.
has been established. A hopper 18 communicating with the cylinder chamber 13A is provided at the upper right side of the plasticizing cylinder 13, and the hopper 18 is supplied to the main part of the outer periphery of the plasticizing cylinder 13 to plasticize the raw resin fed in by the screw 15 and turn it into molten resin. A heater 19 is provided.

Upper mold position control cylinders 20 in the vertical direction are provided on the lower surface of the four corners of the fixed plate 2, and their upward piston rods penetrate the fixed plate 2 and abut against the lower surface of the upper mold 6A. The slider 2 of the upper die position sensor 21 is attached to one of the downward piston rods.
1A is provided, and a position signal of the upper die 6A is transmitted from the slider 21A depending on the position in contact with the stator 21B. Pressure oil is supplied to the cylinder chamber below the piston of the upper mold position control cylinder 20, and the upper mold 6A is pushed up to a desired position against the mold clamping force, thereby making it possible to freely determine the volume of the cavity 7.

Servo valves 22A, 22B, 2 that supply and discharge pressure oil to the mold clamping cylinder 8, main cylinder 10, hydraulic cylinder 17, and upper mold position control cylinder 20, respectively.
2C and 22D are provided, and these hydraulic pumps 23 are connected via a flow rate control valve 24. In addition, these cylinders 8 and 1 excluding the hydraulic cylinder 17
Pressure sensors 25A and 25B are installed on the pressure side of 0 and 20.
and 25C, and a temperature sensor 26 is provided in the cylinder chamber 9B of the injection cylinder 9, and a temperature sensor 26 is provided in the cylinder chamber 9B of the injection cylinder 9.
The data is input to the CPU via . The CPU controls each servo valve 22 and hydraulic motor 14 based on these signals and the data installed and stored in the programmer 27.
A switching signal or an on/off signal is transmitted via /0 to control the mold clamping force of the mold clamping cylinder 8 and its holding time, and control the injection amount and injection force of the main cylinder 0 and its holding time. Mold position control cylinder 2
0, closes the valve 16 and stops the hydraulic motor 14 at the same time as the main cylinder 10 starts injection, and corrects the temperature and pressure of the injection amount of molten resin.

In FIG. 2, several representative examples of molding functions of the multifunctional molding machine 1 are shown. In addition to this, various combination molding functions can be implemented.

Figure 1a is an explanatory diagram of the simple pressure molding function. First, the mold is pushed down by the mold clamping force of the mold clamping cylinder 8 of the upper mold 6A, and then pushed back by the upper mold position control cylinder 20 to form a cavity of h ₀ + h ₁ . After injecting the same amount of molten resin as the cavity of _No. Remove and press mold at high pressure. It has good transferability and has little internal distortion in large, thick-walled molded products, but internal distortion occurs partially in thin-walled products.

Figure 2B is an explanatory diagram of the injection molding function. A cavity of h ₀ is provided between the upper mold 6A and the lower mold 6B, a mold clamping force is applied, and molten resin is injected in an amount equal to the cavity of h ₀ . Shape. Suitable for molding thin-walled molded products at high cycles, but tends to cause sink marks and warpage, and has poor transferability.

Figure 3c is an explanatory diagram of the pressure molding function during injection, where a mold clamping force is applied to the upper mold 6B, an upward force is applied to create a cavity of h ₀ + h ₁ , and an amount of molten resin corresponding to the cavity of h ₀ is poured. After inhalation, the injection is carried out, and before the entire amount has been injected, the push-up force is removed and pressure molding is performed. Both thick-walled and thin-walled molded products can be obtained with good transferability and no internal distortion.

Figure 4 d is an explanatory diagram of the pressure molding function after injection molding, in which a cavity of h ₀ is created by applying mold clamping force to the upper mold 6A and then an upward force, and the same amount of molten resin as the cavity of h ₀ is applied. is injected after inhalation, and after injection is completed, the push-up force is removed and pressure molding is performed. Thin-walled molded products can be molded with good transferability.

Figure 5e is an explanatory diagram of the cushion molding function. A cavity of h ₀ is provided between the upper mold 6A and the lower mold 6B, a mold clamping force is applied, and a larger amount of molten resin than the cavity of h ₀ is sucked in and then injected. Then, mold while applying the required injection force. Although it has the same functions as a normal injection molding machine and is suitable for simple molding, it tends to cause internal distortion in the gate part of the molded product, and the transferability of large molded products is not good.

Figure 6 f is an explanatory diagram of the injection compression molding function, and the upper mold 6
After applying mold clamping force to A, adding push-up force to h ₀ +8
A cavity is provided, and an amount of molten resin equivalent to the cavity h ₀ +8 is sucked and injected, and after the injection, the push-up force is removed and compression molding is performed to h ₀ . Although it is possible to improve the transferability of large molded products and the distortion of the gate portion of the molded product to some extent, some plastic deformation remains after cooling due to elastic recovery after molding.

In the above-described pressure (compression) molding during molding, the pressing force of the mold clamping cylinder 8 and the main cylinder 10 and the holding time thereof are changed in stages, and a method used in normal molding is applied. Further, the oil pressure of the upper mold position control cylinder 20 is reduced and controlled by the oil pressure of the main cylinder 10 so that positional fluctuations do not occur.

"Effects of the Invention" As is clear from the above explanation, according to the present invention, the pressurizing force of the mold clamping cylinder, the main cylinder, and the upper mold position control cylinder, and the position control of the latter two can be mutually controlled at the required timing. You can do it freely with
Multifunctional molding can be performed. Therefore, there is no need to prepare a molding machine for each molding function as in the past, and it is possible to meet the molding needs of a wide variety of molded products. The practical effects and benefits are great.

[Brief explanation of the drawing]

FIG. 1 is a front view and a control circuit block diagram of the embodiment, with main parts thereof in section, and FIGS. 2a to 2f are explanatory diagrams of the molding function according to the embodiment. 1 is a multifunctional molding machine, 2 is a fixed plate, 3 is a substrate, 4 is a tie rod, 5 is a movable plate, 6 is a mold, 6A is an upper mold, 6B is a lower mold, 7 is a cavity,
8 is a mold clamping cylinder, 9 is an injection cylinder, 10 is a main cylinder, 11 is a plunger, 12 is a position sensor, 13 is a plasticizing cylinder, 14 is a hydraulic motor, 15 is a screw, 16 is a valve, 17 is a hydraulic cylinder, 18 is a hopper, 19 is a heater, 20 is an upper mold position control cylinder, 21 is an upper mold position sensor,
22 is a servo valve, 23 is a hydraulic pump, 24 is a flow control valve, 25 is a pressure sensor, 26 is a temperature sensor, and 27 is a programmer.

Claims (1)

[Claims for Utility Model Registration] Lower mold 6B provided on the upper surface of the horizontal fixing plate 2
, an upper mold 6A provided on the lower surface of a movable plate 5 that faces the lower mold 6B from above and moves up and down; a cavity 7 formed between the upper mold 6A and the lower mold 6B; 6B, a mold clamping cylinder 8 that can freely control the mold clamping force, the holding time of the mold clamping force, and the compression timing of the mold clamping force, and a shaft off valve for preventing backflow at the outlet thereof. It is connected to an injection cylinder 9 whose outlet is connected to the cavity 7, and a plunger that advances and retreats into the cylinder chamber of the injection cylinder 9, and is connected to the injection force and injection amount of the plunger, the holding time of the injection force, and the injection force of the mold clamping cylinder 8. A main cylinder 10 that can freely control the injection timing corresponding to the compression timing, a plasticizing cylinder 13 that supplies molten resin to the injection cylinder 9, and a flow path from the plasticizing cylinder 13 to the injection cylinder and the plasticizing cylinder 13. A valve 16 is provided to close toward the main cylinder 10 and is controlled to open and close in conjunction with the main cylinder 10;
and an upper mold position control cylinder 20 that can freely control the height direction position of the upper mold 6A by pushing it up against the mold clamping force of the mold clamping cylinder 8.